Galaxy S7 OLED Display Technology Shoot-Out
Samsung Galaxy S7
Galaxy S7 Edge
Dr. Raymond M. Soneira
President, DisplayMate Technologies
Corporation
Copyright © 1990-2016 by DisplayMate
Technologies Corporation. All Rights Reserved.
This article, or any part
thereof, may not be copied, reproduced, mirrored, distributed or incorporated
into any other work without
the prior written permission of DisplayMate Technologies Corporation
|
|
|
Galaxy S7
|
and
|
Galaxy S7 Edge
|
Introduction
The key element for a great
Smartphone has always been a truly innovative and top performing display, and
the best leading edge Smartphones have always flaunted their super high tech
displays. It is the display performance that determines how good and how
beautiful everything on the Smartphone looks, including camera photos, and also
how usable and how readable the screen remains in high ambient lighting. It is the crown jewel of the Smartphone.
The new Galaxy S7 and Galaxy S7 Edge are Samsung’s new flagship Smartphones with OLED displays.
The Galaxy S
series and Galaxy Note series are how they show off their latest OLED displays
and display technology. They have been alternately releasing one of these
models every six months, so there are two OLED generations per year. Each new
generation has provided significant enhancements and improvements, so they
leapfrog each other in display performance, resulting in a new Best Performing Display
with each new generation. As a result, OLEDs have developed into excellent high
performance displays.
This article is an independent objective scientific analysis of OLED
displays written for consumers and journalists. It is the latest edition in our
six year article series that has tracked and analyzed the development of mobile
OLED displays and display technology, from its early beginnings in 2010, when
OLED displays started out in last place, into a rapidly improving and evolving
display technology that now has a commanding first place lead and continues
pushing ahead aggressively. There is no better confirmation of this than a
series of recent well founded rumors from a number of prominent publications
that Apple will be switching the iPhone to OLED displays in 2018, or possibly
2017 for premium models. More on this topic on the Future
of OLED Smartphones in the Conclusions.
Overview
Samsung provided us with pre-announcement early production units so we
could publish our comprehensive display tests and analysis during the Mobile
World Congress.
The Galaxy S7 and Galaxy S7 Edge are two versions of Samsung’s latest OLED display
technology. The Galaxy S7 has a 5.1 inch high resolution Quad HD 2560x1440
pixel display with 577 pixels per inch on a hard glass substrate. While its
screen size and resolution remain the same as the Galaxy S6, its display has
significantly improved performance that we will cover below.
The Galaxy S7 Edge display is similar to the Galaxy S7, but it has a curved
screen OLED display that is manufactured on a flexible plastic substrate so
that it can bend around the corners on both the sides of the phone to provide
two display areas that can be viewed and controlled from both the front or the
sides, which is especially useful for viewing notifications and scrolling news
items. The Galaxy S7 Edge has a somewhat larger 5.5 inch screen, but has the
same 2560x1440 resolution with 535 pixels per inch.
Our detailed Lab tests show there have been a number of significant
display performance improvements for the new Galaxy S7 and Galaxy S7 Edge
including a much higher maximum brightness and contrast in high ambient light,
together with a significantly improved Automatic Brightness that provides much
better screen visibility in high ambient light, all resulting in a number of
new records for Smartphone display performance, and delivering absolutely
stunning and beautiful images.
We’ll cover these issues and much more, with in-depth comprehensive
display tests, measurements and analysis that you will find nowhere else.
What’s New
I’m glad that Samsung
decided to keep the Galaxy S7 screen size and resolution the same as on the
Galaxy S6, because they look perfectly sharp (for normal 20/20 human vision)
under all normal viewing conditions, so it was pointless to increase them.
Samsung has instead concentrated on increasing the display’s maximum brightness
and improving its performance in ambient light, which has real demonstrable and
easy to see visual benefits that every consumer will immediately appreciate. We’ll
compare the displays on the Galaxy S7 to the Galaxy S6 and the flagship Galaxy
Note 5 in detail below.
Both of the new Galaxy
smartphones have a new interactive Personalized
Automatic Brightness Control that learns and remembers the display
brightness settings that you set for different ambient light levels so you get
your own customized personal visual brightness preferences instead of some
pre-programmed manufacturer settings found in other smartphones, tablets, and
TVs. There is also a new Always On Display mode that will show various personalized clock, calendar,
status messages, notifications, and images on the main screen whenever the
phone is off (in standby), which is possible with very low power on an OLED.
We’ll examine these and other display improvements in the New Display Highlights and Results Highlights sections
below.
The Display Shoot-Out
To examine the
performance of the new Galaxy OLED Displays we
ran our in-depth series of Mobile
Display Technology Shoot-Out Lab tests and measurements in order to
determine how the latest OLED displays have improved. We take display quality
very seriously and provide in-depth objective analysis based on detailed
laboratory tests and measurements and extensive viewing tests with both test
patterns, test images and test photos. To see how far OLED and LCD mobile
displays have progressed in just six years see our 2010 Smartphone
Display Shoot-Out, and for a real history lesson see our original 2006 Smartphone Display
Shoot-Out.
Samsung provided DisplayMate Technologies with pre-release early
production units of the Galaxy S7 so that we could perform our well known
objective and comprehensive DisplayMate Lab tests, measurements, and analysis,
explaining the in-depth display performance results for consumers, reviewers,
and journalists. This article will focus primarily on the Galaxy S7, but we
have also included a section covering the Galaxy S7 Edge.
New Galaxy S7 Display Highlights
While the Galaxy S7
screen size and resolution remain the same as the Galaxy
S6, its display has been significantly improved for most display
performance metrics.
Much Higher Display Brightness and Contrast in Ambient Light
The Galaxy S7 has a
Maximum Brightness that is 24% higher than the Galaxy S6,
which is a significant and visually noticeable improvement, particularly in
high ambient light. The Contrast and Contrast Rating in High Ambient Light have
also significantly improved. We’ll cover these in detail below.
Matches and then Leapfrogs the Galaxy Note 5 Display
Performance
The 5.1 inch Galaxy S7
matches or exceeds all of the display performance metrics of Samsung’s flagship
5.7 inch Galaxy
Note 5, but accomplishes that on a much smaller screen at a higher 577
pixels per inch (ppi) compared to 518 ppi on the Note 5. Since the Galaxy Note
5 pixels are 24% larger (in area) than the pixels on the Galaxy S7, the Galaxy
S7 pixels need to output at a 24% higher level in order to deliver the same
brightness and performance. We’ll cover this in detail below.
New Interactive Personalized Automatic Brightness Control
that Works Well
One of my major
long-term peeves has been how poorly the Automatic Brightness Controls work on
all smartphones, tablets, and TVs. They don’t properly adjust the screen
Brightness for the existing current level of ambient light properly. Sometimes
the display is too bright and other times too dim. As a result many (and
possibly most) people simply turn off Automatic Brightness and permanently park
the Brightness at some fixed high level, which not only reduces the running
time on battery, but also means the display brightness is once again set wrong
most of the time. I covered this in detail back in 2010, with an article called
BrightnessGate
that described “How Automatic Brightness Should Work.” The Galaxy S7 has now
implemented it, and is the first to do Automatic Brightness correctly!
The Galaxy S7 has a new
interactive Personalized Automatic Brightness Control
that learns and stores the display brightness settings that you set for
different ambient light levels, so from then on you get your own customized
personal visual brightness preferences instead of some pre-programmed
manufacturer settings found in other smartphones, tablets, and TVs. We’ll cover
this in more detail below.
New Always On Display
An interesting function that first appeared on the Galaxy Note 4 Edge in
2014 was always keeping a portion of the OLED screen on when the phone is off
(in standby), so certain content can be displayed all day and all night long,
but with a very small power drain that has very little effect on the battery
running time. This is possible on an OLED display with a mostly black
background because every sub-pixel is independently powered, so black pixels
and sub-pixels don’t use any power.
The new Always On Display mode shows various personalized clock, calendar, status
messages, notifications, and images on the main screen when the phone is on
standby. It measures the ambient light level and has both day and night modes,
plus it’s smart enough to stay off when the phone display is face down, or it
senses a dark confined space such as a pocket or handbag. The OLED
display produces an illuminated main screen image 24 hours a day so you can
always discreetly check it with just a glance. As a result, the OLED Always On
Display will reduce the need for a smartwatch, which seems likely to become an
endangered species. We’ll cover this in more detail below.
Can be Used with Polarized Sunglasses
Almost all displays emit polarized light. As a result, if
you are wearing polarized sunglasses the display may appear dark or invisible
in either the portrait or landscape orientations. This is almost always the
case with LCDs and many manufacturers still seem oblivious to this problem,
which I pointed out back in 2012 in this news article. But it’s still
an issue – for example, with polarized sunglasses the iPhone 6 and 6s screens
are significantly darkened in the normal portrait orientation (rather than in
the less used landscape orientation). The ideal solution is to set the
polarizer angle to 45 degrees so that the display is equally bright in both
landscape and portrait orientations – unfortunately many LCD technologies can’t
do that. OLED displays don’t emit polarized light, however, all of the Galaxy
OLED displays (including the S6, S7, and Note 5) include a polarizer (as part
of a Quarter Wave Plate) to significantly reduce screen Reflectance of ambient
light, and… it’s oriented at the ideal 45 degree angle so you can watch the
OLED screen with polarized sunglasses in both the portrait and landscape orientations!
Display Related Enhancements
· The Galaxy S7
is IP68 water and dust resistant like the Galaxy S5 (the Galaxy S6 was not),
which means you can comfortably view the display in typical wet and outside
conditions.
· The Galaxy S7
accepts a microSD card like the Galaxy S5 (the Galaxy S6 does not). This makes
it easier to add large photo and video files.
· The Galaxy S7
has an 18 percent larger 3000 mAh battery compared to the 2550 mAh battery on
the Galaxy S6. This should significantly increase the battery running time
unless you insist on running the display close to its Maximum Brightness all
the time.
Results Highlights
In this section we review and also explain the principal
results from the DisplayMate Lab tests and measurements covered in the Display
Shoot-Out Comparison Table under the following categories: Display
Specifications, Overall
Assessments, Screen
Reflections, Brightness
and Contrast, Colors
and Intensities, Viewing
Angles, OLED Spectra,
Display
Power.
You can skip this Results
Highlights section and go directly to the Galaxy S7
Conclusions and the Galaxy
S7 Edge Overview.
Systematically Improving OLED
Displays
Samsung has been systematically improving OLED display
performance twice a year with each Galaxy generation since 2010. With the Galaxy S7 there are many significant improvements
over the Galaxy
S6 that we tested a year ago, but also with the Galaxy Note 5
that we tested 6 months ago. The most immediately noticeable improvements for
the Galaxy S7 are in Maximum Brightness and its performance in High Ambient
Light, which we discuss in turn below.
2.5K Quad HD 2560x1440
Display
The Galaxy S7 has a 5.1
inch Quad HD 2560x1440 pixel display, currently the highest resolution for
smartphones, with 3.7 Mega Pixels, almost double the number on your HDTV. It
provides lots of image detail – it can display four complete HD 1280x720 images
at once. The display has Diamond Pixels (see
below) and Sub-Pixel Rendering with 577 pixels per inch (ppi), providing
significantly higher image sharpness than can be resolved with normal 20/20
Vision at the typical viewing distances of 9 inches or more for smartphones, so
the display appears perfectly sharp.
In addition, the Galaxy S7 uses Sub-Pixel Rendering,
which further improves image sharpness because the individual Red, Green and
Blue Sub-Pixels are treated as independent addressable image elements and are
not bound together into fixed Pixels, so the closest sub-pixel is used when
rendering the image. In some cases Sub-Pixel Rendering can make the screen
appear to have up to 3 times the resolution of traditional Pixel Rendering. See
Diamond Pixels below.
I’m glad that Samsung decided to keep the Galaxy S7
resolution at 2560x1440 pixels with 577 ppi. The Galaxy S7 looks perfectly
sharp (for normal 20/20 human vision) under all normal viewing conditions,
which always includes some ambient lighting that always lowers the visible image
contrast and perceived image sharpness (Modulation Transfer MTF) – note that
displays are almost never viewed in absolute darkness under perfect viewing
conditions with ideal image content. As a result, it is
absolutely pointless to further increase the display resolution and pixels per
inch (ppi) for a marketing wild goose chase into the stratosphere… We’ll
discuss this important issue and how to improve the Next
Generation of Mobile Displays below.
Multiple Screen Modes and
Color Management
One very important capability of
the Galaxy Smartphones that is often overlooked by many consumers and
reviewers, is the set of user selectable Screen Modes. Most Smartphones
and Tablets only provide a single fixed factory display Color Gamut and color
calibration, with no way for the user to alter it based on personal
preferences, running applications, or Ambient Light levels. A very important
capability provided by the OLED Galaxy Smartphones is the implementation of
Color Management that provides a number of user selectable Screen Modes, each
with different Color Gamuts and levels of Color Saturation and display
calibration based on user and application preferences. Color
Management with multiple and varying Color Gamuts are a very useful and
important state-of-the-art capability that all manufacturers will need to
provide in the future.
The Galaxy S7 has four user selectable Screen Modes:
Adaptive Display, AMOLED Photo, AMOLED Cinema, and the Basic Screen Mode, which
matches the Standard sRGB / Rec.709 Color Gamut that is used for producing
virtually all current consumer content. See this Figure for the Color Gamuts
of the different tested Screen Modes and the Colors
and Intensities section for measurements and details. Note that the Adaptive Display mode is the standard and
factory default Screen Mode. Use Display
Settings to switch between the three other available Screen Modes. We
discuss each of the tested Screen Modes next…
Adaptive Display Screen Mode
with a Wide Color Gamut
The Adaptive Display screen mode
provides real-time adaptive processing to dynamically adjust images and videos
– for some applications it will vary the White Point, Color Gamut, and Color
Saturation based on the image content and the color of the surrounding ambient
lighting measured by the Ambient Light Sensor (which measures color in addition
to brightness). The Adaptive Display mode also delivers significantly higher
Color Saturation, with a large 131 percent of
the Standard sRGB / Rec.709 Color Gamut, among the highest that we have ever
measured for Smartphones and Tablets. Some people like the extra saturated and
vibrant colors, plus it is useful for special applications, and for viewing the
display in medium to high levels of Ambient Light, because it offsets some of
the reflected light glare that washes out the on-screen image colors.
AMOLED Photo Screen Mode with
a Very Accurate Adobe RGB Color Gamut
Most high-end digital cameras have an option to use the
Adobe RGB Color Gamut, which is 17 percent larger than the Standard sRGB /
Rec.709 Color Gamut used in consumer cameras. The AMOLED
Photo screen mode on the Galaxy S7 provides a very accurate calibration
to the Adobe RGB standard, which is rarely available in consumers displays, and
is very useful for high-end digital photography and other advanced imaging
applications. The measured Absolute Color Accuracy of the AMOLED Photo screen
mode for the Galaxy S7 is 1.6 JNCD, which is
very high color accuracy. See this Figure for an explanation
and visual definition of JNCD and the detailed Color Accuracy Plots
showing the measured Color Errors for 41 Reference
Colors distributed throughout the entire Color Gamut. There are very few
consumer displays that can accurately reproduce the Adobe RGB Gamut, so this is
a significant plus for serious photography enthusiasts. See the Color
Accuracy section and the detailed Color Accuracy Plots for
measurements and details.
Basic Screen Mode with a Very Accurate Standard sRGB / Rec.709
Color Gamut
The Basic screen mode
provides a very accurate Color and White Point calibration for the Standard
sRGB / Rec.709 Color Gamut that is used to produce virtually all current
consumer content for digital cameras, TVs, the internet, and computers,
including photos, videos, and movies. The Color Gamut of the Basic screen mode
is very accurate, with a nearly perfect 101 percent of the Standard sRGB /
Rec.709 Color Gamut. Even better, the measured Absolute Color Accuracy for the
Galaxy S7 Basic screen mode is an impressive 1.5 JNCD,
tied with the Galaxy Note 5 and Galaxy S6 for the most
color accurate displays that we have ever measured for a smartphone or tablet,
which is visually indistinguishable from perfect, and is very likely
considerably better than your living room TV.
See this Figure for a color
accurate rendering of the Color Gamut and an explanation and visual definition
of JNCD with detailed Color Accuracy Plots
showing how the Galaxy S7 reproduces the 41 Reference
Colors distributed throughout the entire Color Gamut, and also this
regarding Bogus
Color Accuracy Measurements. This article on Absolute Color
Accuracy includes in-depth measurements and analysis of visual color
accuracy for six flagship Smartphones and Tablets.
Use the Basic screen mode for the best color and image
accuracy, which is especially important when viewing photos from family and
friends (because you often know exactly what they actually should look like),
for some TV shows, movies, and sporting events with image content and colors
that you are familiar with, and also for viewing online merchandise, so you
have a very good idea of exactly what colors you are buying and are less likely
to return them. See the Color
Accuracy section and the detailed Color Accuracy Plots for
measurements and details.
Screen Brightness and
Performance in High Ambient Lighting
Mobile displays are often used under relatively bright
ambient lighting, which washes out the image color saturation and contrast,
reducing picture quality and making it harder to view or read the screen. To be
usable in high ambient light a display needs a dual combination of high Screen
Brightness and low screen Reflectance – the Galaxy S7 has both. For most image
content the Galaxy S7 provides over 440 cd/m2
(Luminance, which is a measure of Brightness sometimes called nits), comparable
or higher than most LCD displays in this size class. Its Screen Reflectance is 4.6 percent, close to the
lowest that we have ever measured for a smartphone. Our Contrast Rating for High Ambient Light quantitatively measures
screen visibility and image contrast under bright Ambient Lighting – the higher
the better. As a result of its high Brightness and low Reflectance, the Galaxy
S7 has a Contrast Rating for High Ambient Light that ranges from 88 to 118, among the highest that we have ever
measured for a smartphone.
Higher Automatic Brightness
More importantly, on
the Galaxy S7 the Maximum Brightness can go much higher when Automatic Brightness is turned On, so that users
can’t permanently park the Manual Brightness slider to very high values, which
would run down the battery quickly. High Screen
Brightness is only needed for High Ambient Light, so turning Automatic
Brightness On will provide better high ambient light screen visibility and also
longer battery running time.
When Automatic Brightness
is turned On, the Galaxy S7 produces up to an impressive 855 cd/m2 (nits) in High Ambient Light,
where high Brightness is really needed – it is tied
with the Galaxy Note 5 for the brightest mobile display that we have ever
tested. As a result of its high Brightness and low Reflectance, the
Galaxy S7 has a Contrast Rating for High Ambient Light that ranges from 119 to186, also the highest
that we have ever measured for a Smartphone display. See the Brightness
and Contrast, the High
Ambient Light and the Screen
Reflections sections for measurements and details.
Interactive Personalized
Automatic Brightness that Works Well
The Galaxy S7 has a new
interactive Personalized Automatic Brightness Control
that learns and stores the display brightness settings that you make for
varying ambient light levels, so from then on you get your own customized
personal visual brightness preferences instead of some pre-programmed
manufacturer settings found in other smartphones, tablets, and TVs. It is the
first smartphone, tablet, or TV to do Automatic Brightness correctly. When
Automatic Brightness is turned On (under Display Settings), if you adjust the
Brightness Slider, the Galaxy S7 will remember your setting along with the
current ambient light level that is measured by its Ambient Light Sensor (ALS),
which is located next to the front facing camera just above the top of the
display. From then on the Galaxy S7 will automatically adjust the screen
Brightness by measuring the current ambient light level and then adjusting the
screen Brightness based on the settings you’ve previously made, so you’ll get a
customized screen Brightness setting that you’ve previously trained it to
produce for the current level of ambient light – and you can continue to tweak
and adjust it as needed.
Super Dimming Mode
The Galaxy S7 also has a Super
Dimming Mode that allows the Maximum Screen Brightness to be set all the
way down to just 2 cd/m2 (nits)
using the Brightness Slider. This is perfect for night use on a beside table,
and useful for working comfortably without eye strain or bothering others in
very dark environments, or affecting the eye’s dark adaptation, such as when
using a telescope. The display still delivers full 24-bit color and the picture
quality remains excellent.
Always On Display Mode
The new Always On Display Mode
takes advantage of the low power capability of an OLED display whenever most of
the image pixels are black, because every sub-pixel is independently powered,
and therefore doesn’t use any power when black. So when the phone is off (in
standby) it is possible to always display some text and graphics on a black
background all day and all night without a significant power drain that would
reduce the battery running time. The Always On Display mode uses only 50 to 90
mW (milli-Watts).
The Always On Display on the Galaxy S7 shows various personalized clock,
calendar, status messages, notifications, and images on the main screen when
the phone is in standby. It measures the ambient light level and has both day
and night modes, and it will stay off when the phone display is face down, or
it senses a dark confined space like a pocket or handbag. The display is
updated once a minute for both content and brightness. The day mode has a
Luminance of 60 nits on a black background, which is very readable but not
distracting for normal indoor ambient lighting, and visible outdoors if you
shade the screen with your hand. The night mode is entered for very low ambient
light levels of 2 lux or less and runs like the Super Dimming Mode with 2 nits,
so it won’t distract you if it’s on your bedside table. The OLED display
produces an illuminated main screen image 24 hours a day so you can always
discreetly check it with just a glance. As a result, the OLED Always On Display
will reduce the need for a smartwatch, which seems likely to become an
endangered species.
Diamond Pixels
A
high resolution screen shot (provided by Samsung) shows an interesting
design and sub-pixel arrangement for the Galaxy S7, which Samsung calls Diamond
Pixels. First of all, the Red, Green, and Blue sub-pixels have very
different sizes – Blue is by far the largest because it has the lowest light
emission efficiency, and Green is by far the smallest because it has the
highest efficiency. The alternating Red and Blue sub-pixel arrangement leads to
a 45 degree diagonal symmetry in the sub-pixel layout. This allows vertical,
horizontal, and particularly diagonal line segments and vectors to be drawn
with reduced aliasing and artifacts. In order to maximize the sub-pixel packing
and achieve the highest possible pixels per inch (ppi), that leads to diamond
rather than square or stripe shaped Red and Blue sub-pixels. But not for the
Green sub-pixels, which are oval shaped because they are squeezed between two
much larger and different sized Red and Blue sub-pixels. It’s a form of
high-tech display art…
Display Power Efficiency
Since 2013 the Power Efficiency of the Galaxy S and
Galaxy Note series of smartphones has improved by a very impressive 56%.
However, this year the Power Efficiency has remained the same between the
Galaxy S6 and Galaxy S7.
While LCDs remain more power efficient for images with
mostly full screen white content (like all text screens on a white background,
for example), OLEDs are more power efficient for typical mixed image content
because they are emissive displays so their power varies with the Average
Picture Level (average Brightness) of the image content over the entire screen.
For OLEDs, Black pixels and sub-pixels don’t use any power so screens with Black
backgrounds are very power efficient for OLEDs. For LCDs the display power is
fixed and independent of image content. Currently, OLED displays are more power
efficient than LCDs for Average Pictures Levels of 65 percent or less, and LCDs
are more power efficient for Average Picture Levels above 65 percent. Since
both technologies are continuing to improve their power efficiencies, the
crossover will continue to change with time.
The Always On Display is
super power efficient because most of the image pixels are black, so it
typically requires only 3 to 5 percent of the maximum display power. In
addition, the Galaxy S7 also has an Ultra Power Saving Mode that lowers the
screen Brightness and also sets the background to Black, both of which
significantly reduce display power and can double the running time on battery.
See the Display
Power section for measurements and details.
Viewing Angle Performance
While smartphones are
primarily single viewer devices, the variation in display performance with
viewing angle is still very important because single viewers frequently hold
the display at a variety of viewing angles. The angle is often up to 30
degrees, more if it is resting on a table or desk. While LCDs typically
experience a 55 percent or greater decrease in Brightness at a 30 degree
Viewing Angle, the OLED Galaxy S7 display shows a much smaller 28 percent
decrease in Brightness at 30 degrees. This also applies to multiple
side-by-side viewers as well, and is a significant advantage of OLED displays.
The Color Shifts with Viewing Angle are also relatively small. See the Viewing
Angles section for measurements and details.
Viewing Tests
The Galaxy S7 Basic screen mode provides very nice,
pleasing and very accurate colors and picture quality. Although the Image
Contrast is slightly too high (due to a slightly too steep Intensity Scale), the
very challenging set of DisplayMate Test and Calibration Photos that we use to
evaluate picture quality looked absolutely stunning
and Beautiful, even to my experienced hyper-critical eyes. The Basic
screen mode is the most color accurate mode and is recommended for indoor and
low ambient light viewing of standard consumer content for digital camera, TV,
internet, and computer content, including photos, videos, and movies, and also
for your online purchases in order to see accurate product colors. The Adaptive
Display screen mode has significantly more vibrant and saturated colors. Some
people like that. It is also recommended for viewing in medium to high levels
of ambient light because it offsets some of the reflected light glare that
washes out the image colors.
Galaxy S7 Edge Overview
Along with the Galaxy S7, Samsung is introducing the Galaxy S7 Edge, which is
almost identical to the Galaxy S7 except that it has a very innovative curved
OLED display that extends and bends around to both the right and left side
edges of the phone. The curved Galaxy S7 Edge provides two additional
configurable display areas that can be viewed from both the front or the sides,
or when the phone is placed face down. The Galaxy S7 Edge has a somewhat larger
5.5 inch screen, but has the same 2560x1440 resolution with 535 pixels per
inch. The Galaxy S7 Edge has the same display
performance measurements and metrics as the Galaxy S7, and also all of the same
display functions and features as well, plus a number of additional ones for
the curved Edge.
The
Galaxy S7 Edge is actually a flexible OLED display manufactured on a flexible
plastic substrate rather than on a traditional perfectly flat and hard screen
like almost all other OLED (and LCD) displays. This allows the display itself
to bend, but it is then placed underneath a hard Gorilla Glass 4 cover for
protection and to maintain its desired shape, which for the Galaxy S7 Edge is
curved along the entire right and left side edges.
The curved Galaxy S7 Edge screen provides quick access to
apps, widgets, menus, options, plus a rotating carrousel of edge screens that
you can swipe and flip through with your finger to see the time, weather, color
coded notifications like incoming and missed calls, messages and Emails, plus
active news feeds that continuously scroll along the Edge. The curved Edge
screen provides an important User Interface enhancement for Smartphones. It’s
quite functional and useful, and even fun watching and cycling through the
various Edge screens.
In addition to the
Always On Display for the main screen, the Galaxy S7 Edge has a side night
clock that will dimly show the time all night long on the Edge screen (using
very little power because only a small section of the OLED screen is active) so
it’s also a nice alarm clock as well.
Galaxy S7 Edge Conclusions
What
is especially news worthy and significant is that the performance of the OLED
display on a flexible plastic substrate for the Galaxy S7 Edge is now
essentially the same as on a traditional glass substrate for the Galaxy S7,
even at 500+ pixels per inch and 2560x1440 resolution. The most important point
is that curved and flexible displays are definitely the wave of the future
because they offer many important visual and functional advantages for both mobile
displays and TVs as explained in our 2014
Innovative Displays and Display Technology article. Follow DisplayMate on Twitter to learn
about our Galaxy Note and upcoming display technology coverage.
Galaxy S7 Conclusions: A Very Impressive
Smartphone Display…
The primary goal of this Display Technology Shoot-Out
article series has always been to publicize and promote display excellence
so that consumers, journalists and even manufacturers are aware of and appreciate
the very best in displays and display technology. We point out which
manufactures and display technologies are leading and advancing the
state-of-the-art for displays by performing comprehensive and objective
scientific Lab tests and measurements together with in-depth analysis. We point
out who is leading, who is behind, who is improving, and sometimes
(unfortunately) who is back pedaling… all based solely on the extensive
objective careful Lab measurements that we also publish, so that everyone can judge
the data for themselves as well…
The Conclusions
below summarize all the principal results. See the main Display
Shoot-Out Comparison Table for the complete DisplayMate Lab
measurements and test details, and the Results
Highlights and the Galaxy
S7 Edge Overview sections above for a more detailed introduction and
overview with expanded discussions and explanations.
OLED Display Evolution
What is particularly significant and impressive is that
Samsung has been systematically improving OLED display performance with every
Galaxy generation since 2010, when we started tracking OLED
displays. The first notable OLED Smartphone, the Google
Nexus One, came in decidedly last place in our 2010 Smartphone
Display Shoot-Out. In a span of just six years OLED display technology is
now challenging and even exceeding the performance of the best LCDs. The Galaxy
S7 continues this impressive systematic improvement in OLED displays and
technology.
The Best Smartphone Display
While the Galaxy S7
screen size and resolution remain the same as the Galaxy
S6, its has been significantly improved for most display performance
metrics. The most noticeable one is a Maximum Brightness that is 24% higher
than the Galaxy S6, which is quite a significant improvement in high ambient
light. The Contrast and Contrast Rating for High Ambient Light have also
significantly improved.
Leapfrogs the Galaxy Note 5
The display on the Galaxy S7 matches and even exceeds the performance of
Galaxy Note 5 that we
tested in 2015 and rated it as the Best Performing Smartphone Display that we
had ever tested. This is a particularly significant enhancement because the 5.1
inch Galaxy S7 display is considerably smaller so the display components had to
be scaled down by 20 percent in area from the larger 5.7 inch Galaxy Note 5,
and then still deliver the same Maximum Brightness from the smaller pixels.
New on the Galaxy S7
The Galaxy S7 introduces
two important display enhancements. There is a new interactive Personalized Automatic Brightness Control that learns
and remembers the display brightness settings that you set for various ambient
light levels so you get your own customized personal visual brightness
preferences instead of some pre-programmed manufacturer settings found in other
smartphones, tablets, and TVs. This not only improves the screen readability in
ambient light but also the running time on battery because you’ll just see the
screen Brightness levels that you need. It is the first smartphone, tablet, or
TV to do Automatic Brightness correctly. And there is also a new Always On Display mode that will show various
personalized clock, calendar, status messages, notifications and images on the
main screen whenever the phone is off (in standby), all day and all night,
which can be done with very low power on an OLED, so you can always discreetly
check it with just a glance. As a result, the OLED Always On Display will
reduce the need for a smartwatch, which seems likely to become an endangered
species. Finally, all of the Galaxy OLED displays can be used with polarized
sunglasses in both the portrait and landscape orientations, unlike almost all
LCDs.
The Galaxy S7 matches or breaks
new records in Smartphone display performance for:
Highest Absolute Color Accuracy (1.5 JNCD), Highest Peak
Brightness (855 nits), Highest Contrast Rating in Ambient Light (186), Highest
Screen Resolution (2560x1440), Highest (infinite) Contrast Ratio, and Smallest
Brightness Variation with Viewing Angle (28 percent). In addition, almost every
display lab test and measurement shows some improvements compared to the Galaxy
S6. See the main Display
Shoot-Out Comparison Table for all of the measurements and details.
The Galaxy S7 and Galaxy Note 5 are neck-and-neck record holders for
display performance, effectively tied or alternating between first and second
place in almost all categories except screen size for the much larger Galaxy
Note 5, and the much higher pixels per inch for the Galaxy S7. What is
especially impressive is that the overall display specs and performance of the
Galaxy S7 have been maintained or improved after being scaled down by 20
percent in area from the Galaxy Note 5. So… as
the result of its even higher ppi, the Galaxy S7 becomes the Best Performing
Smartphone Display that we have ever tested.
Performance Summary and The Future
Below we summarize some of the major display performance highlights for
the Galaxy S7 and Galaxy S7 Edge.
Then we discuss The
Future of OLED Smartphones and Improving
the Next Generation of Mobile Displays.
Galaxy S7 Edge and Flexible OLED Displays
The Galaxy S7 Edge is Samsung’s fifth generation of
flexible OLED display. It has the same display performance measurements and
metrics as the Galaxy S7, and also all of the same display functions and
features as well, plus a number of additional ones. The curved edge screen
provides an important User Interface enhancement for Smartphones that we have
described above. It is quite functional and useful, and even fun watching and
cycling through the various Edge screens. Flexible OLEDs are at the cutting
edge and future of OLED technology. See the Galaxy
S7 Edge Overview section above for more details. The current models are
flexible but are maintained permanently curved and rigid under Gorilla glass –
that can and will change in the future, leading to truly
flexible, bendable, and foldable OLED display screens.
Multiple Screen Modes and Color Management
One
very important capability of the Galaxy Smartphones that is often overlooked by
many consumers and reviewers, is its set of user selectable Screen Modes. Most Smartphones only provide a
single fixed factory display color calibration, with no way for the user to
alter it based on personal preferences, running applications, or ambient light
levels. Samsung has implemented Color Management for their OLED Smartphones and
Tablets allowing them to provide multiple Screen Modes with different Color
Gamuts and color calibrations – other Smartphones only provide a single fixed
screen Color Gamut and color calibration. This Figure shows the different
Color Gamuts. Color Management with multiple and
varying Color Gamuts are a very useful and important state-of-the-art
capability that all manufacturers will need to provide in the future. All of
the recent Galaxy models including the S7 and S7 Edge have this important
capability –
see the Next
Generation of Mobile Displays section below.
The Most Accurate Display
Colors
The Basic screen mode on the Galaxy
S7 is tied with the Galaxy Note 5 for the most accurate display colors of any
smartphone or tablet display that we have ever tested, with a measured average Absolute Color Accuracy of 1.5 JNCD, which is visually indistinguishable from
perfect, and is very likely considerably better than your living room TV. See our detailed Absolute Color Accuracy Plots
with 41 Reference Colors and also this regarding
Bogus Color
Accuracy Measurements. Good Color Accuracy is especially important when
viewing photos from family and friends (because you often know exactly what
they actually should look like), for some TV shows, movies, and sporting events
with image content and colors that you are familiar with, and also for viewing
online merchandise, so you have a very good idea of exactly what product colors
you are buying and are less likely to return them. Select
the Basic Screen Mode using Display Settings – it is not the default screen
mode for the Galaxy S7.
Adobe RGB AMOLED Photo Screen
Mode
Most high-end digital cameras have an option to use the
Adobe RGB Color Gamut, which is 17 percent larger than the standard sRGB /
Rec.709 Color Gamut used in consumer cameras. The AMOLED Photo screen mode on
the Galaxy S7 provides a very accurate 1.6 JNCD
calibration to the Adobe RGB standard, which is rarely available in consumer
displays. It is very useful for viewing high-end digital photos and other
advanced imaging applications. This is a significant plus for serious
photography enthusiasts. Select the AMOLED Photo
screen mode using Display Settings – it is not the default screen mode for the
Galaxy S7.
Adaptive Display Screen Mode
with a Wide Color Gamut
The Galaxy S7 OLED display’s native Wide Color Gamut
Adaptive Display screen mode has significantly more vibrant and saturated
colors with its 131 percent of the Standard
(sRGB / Rec.709) Color Gamut, among the highest that we have ever measured for
Smartphones and Tablets. Some people like the extra saturated and vibrant
colors, plus it is useful for special applications and is recommended for viewing
in medium to high levels of ambient light because it offsets some of the
reflected light glare that washes out the on-screen image colors. Select the Adaptive Display screen mode using Display
Settings – note that Adaptive Display is the factory default screen mode for
the Galaxy S7.
The Highest Screen Brightness
and Contrast in High Ambient Light
Mobile displays are often used under relatively bright
ambient lighting, which washes out the image colors and contrast, reducing
picture quality and making it harder to view or read the screen. To be usable
in high ambient light a display needs a dual combination of high screen
Brightness and low screen Reflectance – the Galaxy S7 has both. Its screen Reflectance is 4.6 percent, close to the lowest that
we have ever measured for a smartphone. When Automatic Brightness is turned On,
the Galaxy S7 reaches an impressive maximum screen Brightness
of up to 855 nits in high Ambient Light, where high screen Brightness is
really needed – it is tied with the Galaxy Note 5 for
the Brightest mobile display that we have ever tested. As a result of
its high Brightness and low Reflectance, the Galaxy S7 has a Contrast Rating
for High Ambient Light, which quantitatively measures screen visibility and
image contrast under bright Ambient Light, that ranges from 119 to 186, also tied with the Galaxy Note 5 for the highest Contrast
Rating in High Ambient Light that we have ever measured for any mobile display.
Interactive Personalized
Automatic Brightness that Works Well
The Galaxy S7 has an
important new interactive Personalized Automatic
Brightness Control that learns and stores the display brightness
settings that you make for varying ambient light levels, so from then on you
get your own customized personal visual brightness preferences instead of some
pre-programmed manufacturer settings found in other smartphones, tablets, and
TVs. When Automatic Brightness is turned On, if you adjust the Brightness
Slider, the Galaxy S7 will remember that setting along with the current ambient
light level that is measured by the Ambient Light Sensor (ALS), which is
located next to the front facing camera just above the top of the display. From
then on the Galaxy S7 will automatically adjust the screen Brightness by
measuring the current ambient light level and then adjusting the screen
Brightness based on the settings you’ve previously made, so you’ll get a
customized screen Brightness setting that you’ve previously trained it to
produce for the current level of ambient light. It is the first smartphone,
tablet, or TV to do Automatic Brightness correctly.
Always On Display
The new Always On Display mode
will show various personalized clock, calendar, status messages, notifications
and images on the main screen whenever the phone is off (in standby), all day
and all night, which can be done with very low power on an OLED display with a black background because every sub-pixel is
independently powered. The OLED display produces an illuminated main
screen image 24 hours a day so you can always discreetly check it with just a
glance. As a result, the OLED Always On Display will reduce the need for a
smartwatch, which seems likely to become an endangered species.
The Future of OLED Smartphones
OLEDs have now evolved and emerged as the premium mobile smartphone
display technology. There is no better confirmation of this than a series of
recent well founded rumors from a number of prominent publications that Apple
will be switching the iPhone to OLED displays in 2018, or possibly 2017 for
premium models.
OLED displays provide a number of significant advantages over LCDs
including: being much thinner, much lighter, with a much smaller bezel
providing a near rimless design, plus a very fast response time, better viewing
angles, and an always-on display mode. Many of the OLED performance advantages
result from the fact that every single sub-pixel in an OLED display is
individually directly powered, which results in better color accuracy, image
contrast accuracy, and screen uniformity.
Because of their very flexible power management capabilities, OLEDs are
not only more power efficient than LCDs for most image content, but they now
deliver much higher peak Brightness than LCDs because of this. However, for
mostly all white screen content LCDs are likely to remain brighter and more
power efficient for a while. OLED displays can also be manufactured on flexible
substrates, which allows the screens to be curved and rounded like on Samsung’s
Galaxy Edge and Galaxy
Round displays. Right now the curved flexible OLED displays are protected
under rigid glass, but in the near future OLED products will be foldable and
flexible.
Apple’s rumored move to an OLED iPhone is simply a recognition of all of
the above, particularly as more and more competing smartphones come with OLED
displays. The interesting question is which companies will manufacture the OLED
displays for Apple in sufficient volume? Right now only Samsung and LG
manufacture OLED displays for actual shipping smartphones. According to OLED-Info and OLED Association, which track developments in
the OLED industry, other potential manufacturers include JDI, AU Optronics,
Foxconn, Sharp, and BOE, but there is a long learning curve involved in
producing very high quality OLED displays, particularly in very high volumes,
so other than Samsung and LG, it remains to be seen who will be supplying all
of the OLED iPhone displays. And if Apple wants to use the much harder to
manufacture flexible OLED displays it’s an even bigger question...
Improving the Next Generation
of Mobile Displays
The Galaxy S7 and Galaxy S7 Edge both have very high 2560x1440 pixel
resolution and 535+ pixels per inch (ppi) displays producing images that look
perfectly sharp (for normal 20/20 human vision) under all normal viewing
conditions, which always includes some ambient light that always lowers the
visible image contrast and perceived image sharpness (Modulation Transfer MTF).
Note that displays are almost never viewed in absolute
darkness under perfect viewing conditions with ideal image content. As a result, it is absolutely pointless to further increase
the display resolution and pixels per inch (ppi) for a marketing wild goose
chase into the stratosphere…
With screen size and resolution
already functionally maxed out, manufacturers should instead dedicate their
efforts and resources into improving real world display performance in ambient
light by using advanced technology to restore and compensate for the loss of
color gamut, color saturation, and image contrast, something that every
consumer will benefit from, and will also immediately notice and appreciate –
providing a true sales and marketing advantage…
The most important improvements for both OLED and LCD
mobile displays will come from improving their image and picture quality and
screen readability in real world ambient light, which washes out the screen
images, resulting in reduced image contrast, color saturation, and color
accuracy. The key will be in lowering screen Reflectance and implementing Dynamic Color Management with automatic real-time
modification of the display’s native Color Gamut and Intensity Scales based on
the measured Ambient Light level in order to have them compensate for the
reflected light glare and image wash out including both loss of color
saturation and image contrast from ambient light as discussed in our 2014
Innovative Displays and Display Technology and SID
Display Technology Shoot-Out articles.
The displays, technologies, and
manufacturers that succeed in implementing this new real world high ambient
light performance strategy will take the lead in the next generations of mobile
displays… Follow DisplayMate
on Twitter to learn about these developments and our upcoming display
technology coverage.
DisplayMate Display Optimization Technology
All
smartphone, tablet, monitor and TV displays can be significantly improved using
DisplayMate’s proprietary very advanced scientific analysis and mathematical
display modeling and optimization of the display hardware, factory calibration,
and driver parameters. We help manufacturers with expert display procurement,
prototype development, display performance improvement and optimization,
testing displays to meet contract specifications, and production quality
control so that they don’t make mistakes similar to those that are exposed in
our public Display Technology Shoot-Out series for consumers. This article is a
lite version of our advanced scientific analysis – before the benefits of our DisplayMate Display Optimization
Technology, which can correct or improve all of these issues. If you are a
display or product manufacturer and want to significantly improve display
performance for a competitive advantage then Contact DisplayMate Technologies.
|
|
|
Galaxy S7
|
and
|
Galaxy S7 Edge
|
Display Shoot-Out Comparison Table
Below we
examine in-depth the OLED display on the Samsung
Galaxy S7 based on objective Lab
measurement data and criteria
in the
following sections: Display
Specifications, Overall
Assessments, Screen
Reflections, Brightness
and Contrast,
Colors
and Intensities, Viewing
Angles, OLED Spectra,
Display
Power
For
additional background information see the original articles covering
the Galaxy S6 Display
Technology Shoot-Out and Galaxy Note 5
Display Technology Shoot-Out.
Detailed Test and Measurement Comparisons with the
Galaxy S6 and Galaxy Note 5
You can directly compare the data and measurement results
for the Galaxy S6, the Galaxy S7, and Galaxy Note 5 displays in detail
by using a Tabbed web browser with our comprehensive Lab
measurements and analysis for each of the displays.
For each Tab click on a Link below. The entries are
mostly identical with only minor formatting differences,
so it’s easy to make detailed side-by-side comparisons by
simply clicking through the Tabs.
Samsung Galaxy
S6 Lab Measurements Comparison Table
Samsung Galaxy
S7 Lab Measurements Comparison Table
Samsung
Galaxy Note 5 Lab Measurements Comparison Table
For
comparisons with the other leading Smartphone, Tablet, and Smart Watch displays
see our Mobile Display
Technology Shoot-Out series.
|
Categories
|
Samsung
Galaxy S7
|
Comments
|
|
Display Technology
|
5.1 inch
OLED with Diamond Pixels
|
Organic Light Emitting Diode
Diamond Pixels with
Diagonal Sub-Pixel Symmetry
|
|
Screen Shape
|
16:9 =
1.78
Aspect
Ratio
|
The Galaxy S7 has the same shape as
widescreen TV video content.
|
|
Screen Area
|
11.1 Square
Inches
|
A better measure of size than the
diagonal length.
|
|
Display Resolution
|
2560 x
1440 pixels
2.5K Quad
HD
|
Screen Pixel Resolution.
Quad HD can display four 1280x720 HD
images
|
|
Total Number of Pixels
|
3.7 Mega
Pixels
|
Total Number of Pixels.
|
|
Pixels Per Inch
|
577 PPI
with Diamond Pixels
Excellent
|
Sharpness depends on the viewing distance
and PPI.
See this on
the visual acuity for a true Retina Display
|
|
Sub-Pixels Per Inch
|
Red
408 SPPI
Green 577
SPPI
Blue
408 SPPI
|
Diamond Pixel displays have only half the
number of
Red and Blue Sub-Pixels as standard RGB
displays.
|
|
Total Number of Sub-Pixels
|
Red 1.8
Million Sub-Pixels
Green 3.7
Million Sub-Pixels
Blue 1.8
Million Sub-Pixels
|
Number of Mega Sub-Pixels for Red,
Green, Blue.
Diamond Pixel displays have only half the
number of
Red and Blue Sub-Pixels as standard RGB
displays.
At High PPI this is generally not visible
due to the
use of Sub-Pixel Rendering.
|
|
20/20 Vision Distance
where Pixels or Sub-Pixels
are Not Resolved
|
6.0
inches for White and Green Sub-Pixels with 20/20 Vision
8.4
inches for Red and Blue Sub-Pixels with 20/20 Vision
|
For 20/20 Vision the minimum Viewing
Distance
where the screen appears perfectly sharp
to the eye.
At 10 inches from the screen 20/20 Vision
is 344 PPI.
|
|
Display Sharpness
at Typical Viewing Distances
|
Display
appears Perfectly Sharp
Pixels are
not Resolved with 20/20 Vision
at Typical
Viewing Distances of
10 to 16
inches
|
The Typical Viewing Distances for this
screen size
are in the range of 10 to 16 inches.
Also note that eye’s resolution is much
lower for
Red and Blue color content than White
and Green.
|
|
Appears Perfectly Sharp
at Typical Viewing Distances
|
Yes
|
Typical Viewing Distances are 10 to 18
inches
for this screen size.
|
|
Photo Viewer Color Depth
|
Full
24-bit Color
No
Dithering Visible
256
Intensity Levels
|
Many Android Smartphones and Tablets
still have some form of 16-bit color
depth in the Gallery Viewer.
The Samsung Galaxy S7 does not have this
issue.
|
|
Overall Assessments
This section summarizes
the results for all of the extensive Lab Measurements and Viewing Tests
performed on the display.
See Screen
Reflections, Brightness
and Contrast, Colors
and Intensities, Viewing
Angles, OLED
Spectra, Display
Power.
The
Galaxy S7 has four user selectable Screen Modes that are calibrated for different applications and user
preferences.
Here
we provide results for the Adaptive Display mode, which is a dynamic Wide Color Gamut mode, the AMOLED Photo mode,
which
is calibrated for the Adobe RGB Gamut used in high-end digital photography
and other advanced imaging applications, and
the
Basic screen mode, which is calibrated for the sRGB / Rec.709 Standard
that is used for almost all current consumer camera,
photo, video, movie,
web, and computer content.
|
Categories
|
Adaptive
Display
Wide Color
Gamut
|
AMOLED
Photo mode
Adobe RGB
Gamut
|
Basic mode
SRGB/Rec.709
Gamut
|
Comments
|
|
Viewing Tests
in Subdued Ambient Lighting
|
Very Good
Images
Photos and
Videos
have Vivid
Color
and
Accurate Contrast
Wide Color
Gamut Mode
Intentionally
Vivid Colors
|
Very Good
Images
Adobe RGB
Photos
have
Excellent Color
and
Accurate Contrast
Accurate
Pro Photo Mode
|
Very Good
Images
Photos and
Videos
have
Excellent Color
and
Accurate Contrast
Accurate
Std Mode
|
The Viewing Tests examine the accuracy
of
photographic images by comparing the
displays
to an calibrated studio monitor and TV.
|
|
Variation with Viewing Angle
Colors and Brightness
See Viewing
Angles
|
Small Color
Shifts
with
Viewing Angle
Small
Brightness Shifts
with
Viewing Angle
|
Small Color
Shifts
with
Viewing Angle
Small
Brightness Shifts
with
Viewing Angle
|
Small Color
Shifts
with
Viewing Angle
Small
Brightness Shifts
with
Viewing Angle
|
The Galaxy S7 display has a relatively
small
decrease in Brightness with Viewing
Angle and
relatively small Color Shifts with
Viewing Angle.
See the Viewing
Angles
section for details.
|
|
Overall Display Assessment
Lab Tests and Measurements
|
Excellent
OLED Display
Wide Color
Gamut Mode
|
Excellent
OLED Display
Accurate
Pro Photo Mode
|
Excellent
OLED Display
Accurate
Std Mode
|
The Galaxy S7 OLED Display performed
very well in the Lab Tests and
Measurements.
|
|
|
|
Absolute Color Accuracy
Measured over Entire Gamut
See Figure 2 and Colors
|
Good
Color Accuracy
Colors
More Saturated
Intentionally
Vivid Colors
|
Excellent
Color Accuracy
Color
Errors are Small
Accurate
Pro Photo Mode
|
Excellent
Color Accuracy
Color
Errors are Small
Accurate
Std Mode
|
Absolute
Color Accuracy is measured with a
Spectroradiometer
for 41
Reference Colors
uniformly
distributed within the entire Color Gamut.
See
Figure 2 and Colors
and Intensities for details.
|
|
Image Contrast Accuracy
See Figure 3 and Contrast
|
Very Good
Accuracy
Image
Contrast
Slightly
Too High
|
Very Good
Accuracy
Image
Contrast
Slightly
Too High
|
Very Good
Accuracy
Image
Contrast
Slightly
Too High
|
The
Image Contrast Accuracy is determined by
measuring
the Log Intensity Scale and Gamma.
See
Figure 3 and Brightness
and Contrast for details.
|
|
Performance in Ambient Light
Display Brightness
Screen Reflectance
Contrast Rating
See Brightness
and Contrast
See Screen
Reflections
|
High
Display Brightness
Very Low
Reflectance
High
Contrast Rating
for
Ambient Light
Higher
Brightness with
Auto
Brightness On
|
High
Display Brightness
Very Low
Reflectance
High
Contrast Rating
for
Ambient Light
Higher
Brightness with
Auto
Brightness On
|
High
Display Brightness
Very Low
Reflectance
High
Contrast Rating
for
Ambient Light
Higher
Brightness with
Auto
Brightness On
|
Smartphones
are seldom used in the dark.
Screen
Brightness and Reflectance determine
the
Contrast Rating for High Ambient Light.
See
the Brightness
and Contrast section for details.
See
the Screen
Reflections section for details.
|
|
Overall Display Calibration
Image and Picture Quality
Lab Tests and Viewing Tests
|
Vivid Saturated Colors
Wide Color
Gamut Mode
|
Excellent Calibration
Accurate
Pro Photo Mode
|
Excellent Calibration
Accurate
Std Mode
|
Galaxy S7 display has multiple Screen
Modes
that delivers accurately calibrated
colors and images
and a Wide Color Gamut Mode that is
preferred by
some users and for some applications.
|
|
|
Overall Display Grade
Overall
Assessment
|
Overall Galaxy S7 Display Grade
is Excellent A
The Best Performing
Smartphone Display that we have ever tested.
Samsung continues systemic
improvements of OLED Displays
|
The Galaxy S7 display delivers excellent
image quality, has both Color Accurate
and
Wide Color Gamut Vivid Color modes, has
high Screen Brightness and low
Reflectance,
has good Viewing Angles, and is an all
around
top performing Smartphone display.
|
|
Wide Color Gamut Mode
Also Best
for Viewing in
High
Ambient Light
|
Accurate
Pro Photo Mode
For Viewing
High-End
Adobe RGB
Photos
|
Accurate
Std Mode
For Viewing
Most Content
Photo Video
Movie Web
|
|
|
Adaptive
Display
Wide Color
Gamut
|
AMOLED
Photo mode
Adobe RGB Gamut
|
Basic mode
sRGB/Rec.709
Gamut
|
Comments
|
|
Screen Reflections
All display screens are mirrors good enough to use
for personal grooming – but that is actually a very bad feature…
We measured the light reflected from all directions
and also direct mirror (specular) reflections, which are much more
distracting and cause more eye strain. Many
Smartphones still have greater than 10 percent reflections that make the
screen much harder to read even in moderate ambient
light levels, requiring ever higher brightness settings that waste
precious battery power. Hopefully manufacturers
will reduce the mirror reflections with anti-reflection coatings and
matte or haze surface finishes.
Our Lab Measurements include Average Reflectance
for Ambient Light from All Directions and for Mirror Reflections.
Note that the Screen Reflectance is exactly the
same for all of the Screen Modes.
The Galaxy S7 has one of the lowest
screen Reflectance levels that we have ever measured for a Smartphone.
The Galaxy S7 is effectively tied with
the Galaxy S6 and the Galaxy Note 5 on low screen Reflectance.
|
Categories
|
Galaxy
S7
|
Comments
|
|
Average Screen Reflection
Light From All Directions
|
4.6
percent
for
Ambient Light Reflections
Excellent
|
Measured using an Integrating Hemisphere
and
a Spectroradiometer. The best value we
have
ever measured for a Smartphone is 4.4
percent.
|
|
Mirror Reflections
Percentage of Light Reflected
|
5.8 percent
for Mirror Reflections
Very Good
|
These are the most annoying types of
Reflections.
Measured using a Spectroradiometer and a
narrow
collimated pencil beam of light
reflected off the screen.
|
|
Brightness and Contrast
The Contrast Ratio
is the specification that gets the most attention, but it only applies for
low ambient light, which is seldom
the case for mobile displays. Much more important
is the Contrast Rating, which indicates how
easy it is to read the screen
under high ambient lighting and depends on both
the Maximum Brightness and the Screen Reflectance. The larger the better.
The display’s actual on-screen Contrast Ratio changes with the Ambient Light lux
level and is proportional to the Contrast Rating.
The Galaxy S7 is 19 to 29 percent
Brighter than the Galaxy S6 and effectively tied with the Galaxy Note 5 for
screen Brightness.
|
Categories
|
Adaptive
Display
Wide Color
Gamut
|
AMOLED
Photo mode
Adobe RGB
Gamut
|
Basic mode
sRGB/Rec.709
Gamut
|
Comments
|
|
Measured Average Brightness
50% Average Picture Level
|
Brightness
458 cd/m2
Very Good
|
Brightness
444 cd/m2
Very Good
|
Brightness
444 cd/m2
Very Good
|
This is the Brightness for typical
screen content
that has a 50% Average Picture Level.
|
|
Measured Full Brightness
100% Full Screen White
|
Brightness
414 cd/m2
Very Good
|
Brightness
404 cd/m2
Very Good
|
Brightness
405 cd/m2
Very Good
|
This is the Brightness for a screen that
is entirely
all white with 100% Average Picture
Level.
|
|
Measured Peak Brightness
1% Full Screen White
|
Brightness
543 cd/m2
Excellent
|
Brightness
521 cd/m2
Excellent
|
Brightness
521 cd/m2
Excellent
|
This is the Peak Brightness for a screen
that
has only a tiny 1% Average Picture
Level.
|
|
Measured Auto Brightness
in High Ambient Light
with Automatic Brightness On
|
Auto
Brightness
549 – 855
cd/m2
Excellent
|
Auto
Brightness
549 – 855
cd/m2
Excellent
|
Auto
Brightness
549 – 855
cd/m2
Excellent
|
Some displays including the Galaxy S7
have
higher Brightness in Automatic
Brightness Mode.
|
|
Low Ambient Light
|
|
Lowest Peak Brightness
Super Dimming Mode
Brightness Slider to Minimum
|
2 cd/m2
For Very
Low Light
|
2 cd/m2
For Very
Low Light
|
2 cd/m2
For Very
Low Light
|
This is the Lowest Brightness with the
Slider set to
Minimum. This is useful for working in
very dark
environments. Picture Quality remained
Excellent.
|
|
Black Brightness at 0 lux
at Maximum Brightness Setting
|
0 cd/m2
Outstanding
|
0 cd/m2
Outstanding
|
0 cd/m2
Outstanding
|
Black brightness is important for low
ambient light,
which is seldom the case for mobile
devices.
|
|
Contrast Ratio at 0 lux
Relevant for Low Ambient Light
|
Infinite
Outstanding
|
Infinite
Outstanding
|
Infinite
Outstanding
|
Only relevant for Low Ambient Light,
which is seldom the case for mobile
devices.
|
|
High Ambient Light
|
|
Contrast Rating
for High Ambient Light
The Higher the Better
for Screen Readability
in High Ambient Light
|
90 – 118
Very Good
119 – 186
With Auto
Brightness
Excellent
|
88 – 113
Very Good
119 – 186
With Auto
Brightness
Excellent
|
88 – 113
Very Good
119 – 186
With Auto
Brightness
Excellent
|
Depends on the Screen Reflectance and
Brightness.
Defined as Maximum Brightness / Average Reflectance.
The display’s actual on-screen Contrast
Ratio
changes with the Ambient Light lux level
and is
proportional to the Contrast Rating.
|
|
Screen Readability
in High Ambient Light
|
Very Good A
Excellent
A+
With Auto Brightness
|
Very Good A
Excellent A+
With Auto Brightness
|
Very Good A
Excellent A+
With Auto Brightness
|
Indicates how easy it is to read the
screen
under high ambient lighting. Depends on
both the Screen Reflectance and
Brightness.
See High
Ambient Light Screen Shots
|
|
Colors and Intensities
The Color Gamut, Intensity Scale, and White Point
determine the quality and accuracy of all displayed images and all
the image colors. Bigger is definitely Not Better
because the display needs to match all the standards that were used
when the content was produced. For LCDs a wider
Color Gamut reduces the power efficiency and the Intensity Scale
affects both image brightness and color mixture
accuracy.
The Galaxy S7 Screen Modes are
calibrated for different applications and user preferences.
The Galaxy S7 is effectively tied with
the Galaxy Note 5 and Galaxy S6 for Color Accuracy and Contrast Accuracy.
|
Categories
|
Adaptive
Display
Wide Color
Gamut
|
AMOLED
Photo mode
Adobe RGB
Gamut
|
Basic mode
sRGB/Rec.709
Gamut
|
Comments
|
|
Color of White
Color Temperature in degrees
Measured in the dark at 0 lux
See Figure 1
|
7,445 K
2.7 JNCD
from D65 White
White is
Somewhat Bluish
Intentionally
Bluish Mode
For Some
Applications
the White
Point Will Vary
with the
Ambient Lighting
|
6,512 K
0.4 JNCD
from D65 White
Very Close
to Standard
Accurate
Pro Photo Mode
See Figure 1
|
6,480 K
0.4 JNCD
from D65 White
Very Close
to Standard
Accurate
Std Mode
See Figure 1
|
D65 with 6,500 K is the standard color
of White
for most Consumer Content and needed for
accurate color reproduction of all
images.
JNCD is a Just Noticeable Color Difference.
White Point accuracy is more critical than
other colors.
See Figure 1
for the plotted White Points.
See Figure 2 for the
definition of JNCD.
|
|
Color Gamut
Measured in the dark at 0 lux
See Figure 1
|
131
percent
sRGB /
Rec.709
Intentionally
Vivid Colors
Wide Color
Gamut Mode
See Figure 1
|
100
percent
Adobe RGB
Very Close
to Standard
Accurate
Pro Photo Mode
See Figure 1
|
101
percent
sRGB /
Rec.709
Very Close
to Standard
Accurate
Std Mode
See Figure 1
|
sRGB / Rec.709 is the color standard for
most
content and needed for accurate color
reproduction.
Many advanced digital cameras use Adobe
RGB.
A Wide Color Gamut is useful in High
Ambient Light
and for some applications. It can be used
with Color
Management to dynamically change the
Gamut.
|
|
Color Accuracy
|
|
Absolute Color Accuracy
Average Color Error at 0 lux
For 41 Reference Colors
Just Noticeable Color Difference
See Figure 2
|
Average
Color Shift
From sRGB
/ Rec.709
Δ(u’v’)
= 0.0265
6.6 JNCD
Intentionally
Vivid Colors
Wide Color
Gamut Mode
See Figure 2
|
Average
Color Error
From Adobe
RGB
Δ(u’v’)
= 0.0065
1.6 JNCD
Excellent
Accuracy
Accurate
Pro Photo Mode
See Figure 2
|
Average
Color Error
From sRGB
/ Rec.709
Δ(u’v’)
= 0.0062
1.5 JNCD
Excellent
Accuracy
Accurate
Std Mode
See Figure 2
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD and for
Accuracy Plots showing
the measured Color Errors.
Average Errors below 3.5 JNCD are Very
Good.
Average Errors 3.5 to 7.0 JNCD are
Good.
Average Errors above 7.0 JNCD are
Poor.
|
|
Absolute Color Accuracy
Largest Color Error at 0 lux
For 41 Reference Colors
Just Noticeable Color Difference
See Figure 2
|
Largest Color Shift
From sRGB
/ Rec.709
Δ(u’v’)
= 0.0658
16.4 JNCD
for Cyan-Blue
Intentionally
Vivid Colors
Wide Color
Gamut Mode
See Figure 2
|
Largest Color Error
From Adobe
RGB
Δ(u’v’)
= 0.0218
5.4 JNCD
for Cyan-Blue
Very Good
Accuracy
Accurate
Pro Photo Mode
See Figure 2
|
Largest Color Error
From sRGB
/ Rec.709
Δ(u’v’)
= 0.0209
5.2 JNCD
for Cyan-Blue
Very Good
Accuracy
Accurate
Std Mode
See Figure 2
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD and for
Accuracy Plots showing
the measured Color Errors.
Largest Errors below 7.0 JNCD are
Very Good.
Largest Errors 7.0 to 14.0 JNCD are
Good.
Largest Errors above 14.0 JNCD are
Poor.
This is twice the limit for the Average
Error.
|
|
Intensity Scale and Image Contrast
Accuracy
|
|
Dynamic Brightness
Luminance Decrease with
Average Picture Level APL
|
24 percent
Decrease
Good
|
22 percent
Decrease
Good
|
22 percent
Decrease
Good
|
This is the percent Brightness decrease
with APL
Average Picture Level. Ideally should be
0 percent.
|
|
Intensity Scale and
Image Contrast
See Figure 3
|
Smooth and
Straight
Very Good
Slightly
Too Steep
See Figure 3
|
Smooth and
Straight
Very Good
Slightly
Too Steep
See Figure 3
|
Smooth and
Straight
Very Good
Slightly
Too Steep
See Figure 3
|
The Intensity Scale controls image
contrast needed
for accurate Image Contrast and Color
reproduction.
See Figure 3
|
|
Gamma for the Intensity Scale
Larger has more Image Contrast
See Figure 3
|
2.39
Very Good
Gamma
Slightly Too High
|
2.39
Very Good
Gamma
Slightly Too High
|
2.39
Very Good
Gamma
Slightly Too High
|
Gamma is the log slope of the Intensity
Scale.
Gamma of 2.20 is the standard and needed
for
accurate Image Contrast and Color
reproduction.
See Figure 3
|
|
Image Contrast Accuracy
|
Very Good
|
Very Good
|
Very Good
|
See Figure 3
|
|
Viewing Angles
The variation of
Brightness, Contrast, and Color with Viewing Angle is especially important
for Smartphones because
of their larger screen
and multiple viewers. The typical manufacturer 176+ degree specification for
LCD Viewing Angle
is nonsense because that
is where the Contrast Ratio falls to a miniscule 10. For most LCDs there are
substantial
degradations at less
than ±30 degrees, which is not an atypical Viewing Angle for Smartphones and
Tablets.
Note that the Viewing
Angle performance is also very important for a single viewer because the
Viewing Angle can vary
significantly based on
how the Smartphone is held. The Viewing Angle can be very large if resting on
a table or desk.
The
Viewing Angle variations are essentially identical for all of the Galaxy S7
Screen Modes.
The Galaxy S7 is effectively tied with
the Galaxy Note 5 and Galaxy S6 for Viewing Angle Performance.
|
Categories
|
Adaptive
Display
Wide Color
Gamut
|
AMOLED
Photo mode
Adobe RGB
Gamut
|
Basic mode
sRGB/Rec.709
Gamut
|
Comments
|
|
Brightness Decrease
at a 30 degree Viewing Angle
|
28 percent
Decrease
Small
Decrease
Very Good
|
Most screens become less bright when
tilted.
OLED decrease is due to optical
absorption.
LCD decrease is generally greater than 50
percent.
|
|
Contrast Ratio at 0 lux
at a 30 degree Viewing Angle
|
Infinite
Contrast Ratio
Outstanding
|
A measure of screen readability when the
screen
is tilted under low ambient lighting.
|
|
White Point Color Shift
at a 30 degree Viewing Angle
|
Small Color
Shift
Δ(u’v’)
= 0.0116
2.9 JNCD Very Good
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD.
|
|
Primary Color Shifts
Largest Color Shift for R,G,B
at a 30 degree Viewing Angle
|
Largest Color Shift
Δ(u’v’)
= 0.0268 for Pure Red
6.7 JNCD Very Good
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD.
Same Rating Scale as Absolute Color
Accuracy.
|
|
Color Shifts for Color Mixtures
at a 30 degree Viewing Angle
Reference Brown (255, 128, 0)
|
Small
Color Shift
Δ(u’v’)
= 0.0132
3.3 JNCD Very Good
|
JNCD is a Just Noticeable Color Difference.
Color Shifts for non-IPS LCDs are about 10
JNCD.
Reference Brown is a good indicator of
color shifts
with angle because of unequal drive
levels and
roughly equal luminance contributions
from Red
and Green. See Figure 2 for the
definition of JNCD.
|
|
Display Power Consumption
The display power was measured using a Linear
Regression between Luminance and AC Power with a fully charged battery.
Since the displays all have different screen sizes
and maximum brightness, the display power values below were also scaled
to the same screen Brightness (Luminance) and same
screen area in order to compare their Relative Power Efficiencies.
Comparison with LCDs
While LCDs remain more power efficient for images with
mostly full screen white content (like all text screens on a
white background, for example), OLEDs are more power
efficient for typical mixed image content because they are
emissive displays so their power varies with the
Average Picture Level (average Brightness) of the image content over
the entire screen. For OLEDs, Black pixels and
sub-pixels don’t use any power so screens with Black backgrounds are
very power efficient for OLEDs. For LCDs the display
power is fixed and independent of image content. Currently,
OLED displays are more power efficient than LCDs for
Average Pictures Levels of 65 percent or less, and LCDs are
more power efficient for Average Picture Levels above
65 percent. Since both technologies are continuing to improve
their power efficiencies, the crossover will continue
to change with time.
Comparison with the Galaxy S6
Below we compare the Relative Display
Power Efficiencies of the Galaxy S7 with the Galaxy S6.
The Galaxy S7 has the same Display
Power Efficiency as the Galaxy S6. The results are scaled for the same Luminance.
|
|
Categories
|
Galaxy
S6
|
Galaxy
S7
|
Comments
|
|
Average Display Power
Maximum Brightness at
50% Average Picture Level
|
50% Average
Picture Level
0.65 watts
with 371
cd/m2
|
50% Average
Picture Level
0.80 watts
with 458
cd/m2
|
This measures the Average Display Power
for
a wide range of image content.
|
|
Relative Power Efficiency
50% Average Picture Level
Compared to Galaxy S6
For the same 371 cd/m2
|
Relative Average Power
100%
0.65 watts
with same 371 cd/m2
|
Relative Average Power
100%
0.65 watts
with same 371 cd/m2
|
This
compares the Relative Power Efficiency
by
scaling the measured Display Power to the
same
screen Brightness and same screen area
as
the Galaxy S6.
|
|
|
|
Maximum Display Power
Full White Screen
at Maximum Brightness
|
Maximum Power
Full Screen White
1.20 watts
with 348 cd/m2
|
Maximum
Power
Full Screen
White
1.45 watts
with 414
cd/m2
|
This measures the Maximum Display power
for
a screen that is entirely Peak White.
|
|
Relative Power Efficiency
Maximum Display Power
Compared to Galaxy S6
For the same 348 cd/m2
|
Relative Maximum Power
100%
1.20 watts
with same 348 cd/m2
|
Relative Maximum Power
102%
1.22 watts
with same 348 cd/m2
|
This
compares the Relative Power Efficiency
by
scaling the measured Display Power to the
same
screen Brightness and same screen area
as
the Galaxy S6.
|
|
|
|
|
|
|
About the Author
Dr. Raymond Soneira is
President of DisplayMate Technologies Corporation of Amherst, New Hampshire,
which produces display calibration, evaluation, and diagnostic products for
consumers, technicians, and manufacturers. See www.displaymate.com. He is a research
scientist with a career that spans physics, computer science, and television
system design. Dr. Soneira obtained his Ph.D. in Theoretical Physics from
Princeton University, spent 5 years as a Long-Term Member of the world famous
Institute for Advanced Study in Princeton, another 5 years as a Principal
Investigator in the Computer Systems Research Laboratory at AT&T Bell
Laboratories, and has also designed, tested, and installed color television
broadcast equipment for the CBS Television Network Engineering and Development
Department. He has authored over 35 research articles in scientific journals in
physics and computer science, including Scientific American. If you have any comments
or questions about the article, you can contact him at dtso.info@displaymate.com.
DisplayMate Display Optimization Technology
All
smartphone, tablet, monitor and TV displays can be significantly improved using
DisplayMate’s proprietary very advanced scientific analysis and mathematical
display modeling and optimization of the display hardware, factory calibration,
and driver parameters. We help manufacturers with expert display procurement,
prototype development, display performance improvement and optimization,
testing displays to meet contract specifications, and production quality
control so that they don’t make mistakes similar to those that are exposed in
our public Display Technology Shoot-Out series for consumers. This article is a
lite version of our advanced scientific analysis – before the benefits of our DisplayMate Display Optimization
Technology, which can correct or improve all of these issues. If you are a
display or product manufacturer and want to significantly improve display
performance for a competitive advantage then Contact DisplayMate Technologies.
About DisplayMate Technologies
DisplayMate Technologies specializes in proprietary advanced
scientific display calibration and mathematical display optimization to deliver
unsurpassed objective performance, picture quality and accuracy for all types
of displays including video and computer monitors, projectors, TVs, mobile
displays such as smartphones and tablets, and all display technologies
including LCD, OLED, 3D, LED, LCoS, Plasma, DLP and CRT. This article is a lite version of
our intensive scientific analysis of Smartphone and Smartphone mobile displays
– before the benefits of our advanced mathematical DisplayMate Display Optimization
Technology, which can correct or improve many of the display deficiencies. We offer DisplayMate display
calibration software for consumers and advanced DisplayMate display diagnostic
and calibration software for technicians and test labs.
For
manufacturers we offer Consulting Services that include advanced Lab testing
and evaluations, confidential Shoot-Outs with competing products, calibration
and optimization for displays, cameras and their User Interface, plus on-site
and factory visits. We help manufacturers with expert display procurement,
prototype development, and production quality control so they don’t make
mistakes similar to those that are exposed in our Display Technology Shoot-Out
series. See our world renown Display
Technology Shoot-Out public article series for an introduction and preview.
DisplayMate’s
advanced scientific optimizations can make lower cost panels look as good or
better than more expensive higher performance displays. If you are a display or
product manufacturer and want to turn your display into a spectacular one to
surpass your competition then Contact
DisplayMate Technologies to learn more.
Article Links: Galaxy S6
OLED Display Technology Shoot-Out
Article Links: Galaxy Note 5
OLED Display Technology Shoot-Out
Article Links: Absolute
Color Accuracy Display Technology Shoot-Out
Article Links: Display Technology Shoot-Out
Article Series Overview and Home Page
Copyright © 1990-2016 by DisplayMate
Technologies Corporation. All Rights Reserved.
This article, or any part
thereof, may not be copied, reproduced, mirrored, distributed or incorporated
into any other work without
the prior written permission of DisplayMate Technologies Corporation
