Pixel 4 XL OLED Display Technology Shoot-Out
Dr. Raymond M. Soneira
President, DisplayMate Technologies
Corporation
Copyright © 1990-2019 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
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Pixel 4 XL
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Introduction and Overview
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 the camera photos,
videos, movies, web content, plus all of your Apps, and also how readable and
how usable the screen is in high ambient lighting. The Display is the crown
jewel of the Smartphone!
In this Display Technology Shoot-Out article series we only
cover the Very Best State-of-the-Art Top Performing and Top Tier Smartphone
Displays. The articles are designed to promote Display Performance so that
consumers, reviewers, and journalists all recognize and appreciate Display
Excellence, and also to reward and encourage manufacturers to produce top
performing displays for their products.
The Pixel 4 XL is Google’s third generation Flagship Smartphone, with an
OLED display that improves on the excellent display performance of the Pixel 3 XL. As
we will show in detail below, the Pixel 4 XL
has a number of notable improvements over the Pixel 3
XL including:10% higher Peak Brightness, much
higher Absolute Color Accuracy, and improved Display Power Efficiency.
In this article we lab test, measure, analyze, and evaluate in depth the
display on the Pixel 4 XL. This is an
independent scientific objective lab test and analysis of OLED displays written
for consumers and journalists. It is the latest edition in our nine year
article series that has lab tested, 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.
We’ll cover all of the these display performance topics and much more,
with in-depth comprehensive display tests, measurements, and analysis that you
will find nowhere else.
The Move to OLED Displays
LCDs are a great cutting edge high performance display technology for
Tablets to TVs, but for small handheld Smartphones, OLED displays provide a
number of significant advantages over LCDs including: being much thinner, much
lighter, without needing a bezel, providing a rimless edge-to-edge design. They
can be made flexible and into curved screens, plus they have 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 independently directly electrically
powered to emit light, so only the active image sub-pixels draw power based on
their individual brightness levels. OLEDs can also provide better color
accuracy, image contrast accuracy, and screen uniformity because the
irregularities and variations in LCD Backlights introduce color and brightness
irregularities and variations over the screen.
As the result of their very versatile 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 the maximum
power can be delivered to just the sub-pixels that are needed for producing the
current image. However, for mostly all White screen content LCDs are likely to
remain brighter and more power efficient for a while.
OLED displays now have tremendous performance advantages over LCDs, so
high-end and flagship Smartphones need OLED displays in order to compete at
state-of-the-art performance levels, securing OLED as the definitive premier
display technology for Top Tier Smartphones in the foreseeable future over the
next 3-5 years. With the continuing improvements in OLED hardware performance,
picture quality, and precision accuracy, it will be much harder for new display
technologies to challenge OLED.
Article Overview
This article has the following major sections:
· Pixel 4 XL
Display Highlights and Performance Results
· Pixel 4 XL Conclusions
· Pixel
4 XL Display Performance Functions and Features
· Pixel 4
XL Display Performance Records
· DisplayMate
Best Smartphone Display Award
· Improving
Display Performance for Real World Ambient Light
· Improving
the Next Generation of Mobile Displays
· Pixel 4 XL Lab Measurements
and Comparison Table
The Display Shoot-Out
To examine the
performance of the new Pixel 4 XL OLED Display
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 nine years see our 2010 Smartphone
Display Shoot-Out, and for a real history lesson see our original 2006 Smartphone Display
Shoot-Out.
Google provided DisplayMate Technologies with a pre-announcement
production unit of the Pixel 4 XL so that we could perform our well known
objective and comprehensive DisplayMate Lab tests, measurements, and analysis,
explaining in-depth the new display performance results for consumers,
reviewers, and journalists as early as possible.
Pixel 4 XL Display Highlights and
Performance Results
In this section we review and explain the principal
results from the extensive DisplayMate Lab Tests and Measurements
in the following categories: Display
Specifications, Overall Assessments, Screen Reflections, Brightness
and Contrast,
Colors and Intensities,
Absolute Color Accuracy, Viewing Angles, OLED Spectra,
Display Power.
Lab Tests and Measurement
Data Table
See the Display Shoot-Out Lab
Measurements Comparison Table for the complete set of DisplayMate Lab Tests
and Measurements.
Main Topics Covered
This Display Highlights and
Performance Results section has detailed information and analysis on the
Pixel 4 XL display for the main topics listed
below.
You can skip this section and go directly to the Pixel 4 XL Conclusions for a Summary of the Display Test
Results.
· Large 6.3 inch Full Screen Display
· 3K High Resolution Quad HD+ Display
· Smooth Display Feature with Refresh Rates up to 90 Hz
· Industry Standard Color Gamuts
· Automatic Color Management
· Very High Contrast Accuracy and Intensity Scale Accuracy
· Peak Brightness that is Independent of the on-screen
Image Content
· Very High Absolute Color Accuracy
· Color Accuracy and Intensity Scales Independent of the
Image Content
· High Screen Brightness and Performance in High Ambient
Light
· High
Dynamic Range Mobile HDR Display
· Night Light Mode for Better Night Viewing
· Always On Display Mode
· Super Dim Setting
· Dark Theme
· Ambient EQ Viewing Mode
· Diamond Sub-Pixels
· Viewing Angle Performance
· Viewing Tests Performance
· Display Power Efficiency
· Display Related Enhancements
· Large 6.3 inch Full Screen Display with a higher Aspect
Ratio of 19 : 9
The Pixel 4 XL has a large 6.3 inch display that fills almost the entire front
face of the phone from edge-to-edge. The display also has a higher form factor
with a taller height to width Aspect Ratio of 19 : 9 = 2.11, which is 22% larger than the 16 : 9 = 1.78 on most
Smartphones (and widescreen TVs) because the display now has the same overall
shape as the entire phone. It is taller in Portrait mode and wider in Landscape
mode. This provides extra space for Notifications and for displaying multiple
Apps and content simultaneously on-screen side-by-side.
· 3K High Resolution Quad HD+ 3040x1440 Display with 537
pixels per inch
As a result of its larger display size and larger Aspect
Ratio, the Pixel 4 XL has a 3K High Resolution Quad
HD+ display with 3040x1440 pixels and 537 pixels per inch, with 4.4 Mega Pixels, more than
double the number on an HDTV. The display has Diamond
Sub-Pixels (see below) and Sub-Pixel Rendering
with 537 pixels per inch (ppi), providing significantly higher image sharpness
than can be resolved with normal 20/20 Vision at the typical viewing distances
of 12 inches or more for Smartphones, so the display appears perfectly sharp. As a result, for Smartphones it is absolutely pointless to
further increase the display resolution and pixels per inch (ppi) up to 4K
(3940x2160 pixels) for a silly marketing wild goose chase into the
stratosphere, with no visual benefit for humans!
· Smooth Display Feature with Refresh Rates up to 90 Hz
Most Smartphones refresh their screens 60 times per
second (Hz) or less. The Pixel 4 XL has a selectable Smooth
Display mode that provides a higher 90 Hz
Refresh Rate for some content (which can increase display power). The
Smooth Display feature automatically adjusts the Refresh Rate between 60 and 90
Hz for optimum viewing and battery use.
The 50% higher Refresh Rate provides several important
advantages, including much smoother scrolling of screen content, and smoother
videos and animation. The higher refresh rate also helps with touch latency and
improves the responsiveness of the Pixel 4 XL.
In addition, some people can sense screen flicker on some
Smartphone displays, which can result in visual fatigue, eye strain, and
headaches. The 50% higher Refresh Rate and higher Pulse Width Modulation Rate
may reduce or eliminate this effect for some users that are affected by display
flicker.
· Industry Standard Color Gamuts
The Pixel 4 XL supports the two most important Industry Standard Color Gamuts: the sRGB / Rec.709 Color
Gamut that is used for most current consumer
content, and the new Wide DCI-P3 Color Gamut that is used in 4K Ultra HD TVs. The DCI-P3 Gamut is
26 percent larger than the sRGB / Rec.709 Gamut. But Automatic Color Management
provides many more Gamuts...
· Automatic Color Management
Most Smartphones and Tablets generally provide only one
to up to several fixed Color Gamuts. The Pixel 4 XL has
Automatic Color Management that automatically switches to the proper
Color Gamut for any displayed image content within the Wide DCI-P3 Color Space
that has an ICC Profile, so images automatically appear with the correct
colors, neither over-saturated or under-saturated. Automatic
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.
· Very High Contrast Accuracy and Intensity Scale Accuracy
The
Intensity Scale (sometimes called the Gray Scale) not only controls the Image
and Picture Contrast within all displayed images but it also controls how the
Red, Green and Blue primary colors mix to produce all of the on-screen colors.
So if the Intensity Scale doesn't accurately follow the Standard that is used
to produce virtually all consumer content then the Image Colors, Image
Contrast, and their Brightness Intensities will be wrong everywhere in all
images. Unfortunately, many manufacturers are quite sloppy with the Intensity
Scale on their displays (because it is logarithmic and not linear).
Fortunately, the Intensity Scale on the Pixel 4 XL (with a Gamma of 2.19) is a
close to perfect match of the Standard Intensity Scale (with a Gamma of 2.20),
which is essential for High Absolute Color Accuracy. See Figure 3 for a plot of the
measured Intensity Scales and the Contrast and Intensity Scale section for the measurements and details.
· Peak Brightness that is Independent of the on-screen Image
Content
The Average Picture Level
(APL) for on-screen image content is the
Average Brightness (Luminance) over the entire screen, which varies from 0% for
an all Black screen, to 100% for an all White screen at Peak Brightness.
On almost all existing OLED displays the Peak Brightness
(Luminance) changes with the Average Picture Level APL of the on-screen image,
with the Peak Brightness increasing by up to 50 percent or more between High
APL and Low APL. This increasing High Brightness with Low APL effect can be
very useful in improving screen readability in High Ambient Light, and also to
highlight certain on-screen image content. But the resulting variations in
display Brightness can distort the brightness relationships when viewing
photos, in videos, and other images, so for High Accuracy the Luminance
variation with APL should be as small as possible.
On the Pixel 4 XL the Luminance variation with picture
content APL is a Record Low of 0.5 to 1 percent. But as we discuss next, the actual
reason for doing this is to improve the Absolute Color Accuracy and Absolute
Contrast Accuracy of the display. See the Screen
Brightness section for the measurements and details.
· Very High Absolute Color
Accuracy
Delivering great color with high Absolute Color Accuracy
is incredibly difficult because everything on the display has to be done just
right. In order to deliver accurate image colors, a display needs to closely
match the standard Color Gamut that was used for producing the content being
viewed – not more and not less. In addition the display also needs an accurate
(pure logarithmic power-law) Intensity
Scale, and an accurate White Point.
Each Pixel 4 XL display is
individually calibrated at the factory for both Color Accuracy and Contrast
Accuracy. Since the Pixel 4 XL supports two Standard Color Gamuts it
needs to also implement Color Management in order to get the second smaller
sRGB / Rec.709 Gamut to also appear correctly, which is generated from the
wider native DCI-P3 Gamut.
The Absolute Color Accuracy
of the Pixel 4 XL is Truly Impressive as shown
in these Figures. It
has an Absolute Color Accuracy of 0.5 JNCD
(Just Noticeable Color Difference) for the sRGB / Red.709 Color Gamut that is
used for most current consumer content, and 0.5 JNCD
for the Wider DCI-P3 Color Gamut that is used for 4K UHD TVs and Digital
Cinema, which are both Visually Indistinguishable From
Perfect, and very likely considerably better than any mobile display,
monitor, TV or UHD TV that you have.
Note that to obtain this High Absolute Color Accuracy
both Ambient EQ and Night
Light need to be Off because they change
the White Point of the display from the 6,500 K Standard, which then changes
the Absolute Color Accuracy throughout the Color Gamut. See this Figure for an explanation
and visual definition of Just Noticeable Color Difference JNCD and the Color Accuracy Plots with
41 Reference Colors showing the measured
display Color Errors. See the Color Accuracy
section and the Color
Accuracy Plots for the measurements and details.
· Color Accuracy and Intensity Scales that are Independent of
the on-screen Image Content APL
The Absolute Color Accuracy and Intensity Scale of the
display should not change as the on-screen image content changes.
With the continuing improvements in display performance
we have added a new set of advanced tests that measure the variations in the
Absolute Color Accuracy and the Intensity Scales with changing Average Picture Level APL,
comparing the Color Shifts between Low APL and 50% High APL. Previous generation
displays with large Peak Luminance changes with APL will show large Shifts in
the Intensity Scale and large Shifts in Absolute Color Accuracy with APL.
Figure
3 shows the variation in the Intensity Scales between Low APL and 50% APL.
Any change in the Intensity Scale will affect the Absolute Color Accuracy.
There is only a small Shift in the Intensity Scales, with the Gamma varying
from 2.19 for Low APL to 2.20 for 50% APL. As a
result, the Image Contrast remains unchanged with varying APL content.
Figure
4 shows the variation in the Absolute Color Accuracy between Low APL and
50% APL. The Color Shifts with APL are very small, with a Record Low Average Color
Shift of just 0.2 JNCD, and the Largest Color
Shifts are only 0.5 JNCD, also a Record Low. The White Point Shifts with APL are just 0.2
JNCD.
All of the Shifts with APL are small, Visually Indistinguishable, and rated Excellent. See this Figure for an explanation
and visual definition of JNCD and the Color APL Shifts section for the measurements and
details.
· High Screen Brightness and Performance in High Ambient Light
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 Pixel 4 XL has both. This is extremely important for
screen readability, picture quality, and color accuracy in ambient light.
The Pixel 4 XL has a
100% APL Calibrated Full Screen Brightness of 444 cd/m2 (nits) for
the sRGB/Rec.709 and DCI-P3 Color Gamuts. On its Home Screen the Pixel 4 XL also produces 444
nits. See the Screen Brightness section for
the measurements and details.
The measured Pixel 4 XL Screen
Reflectance is 4.4 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 Pixel 4 XL has a Contrast Rating
for High Ambient Light that ranges up to 102, among
the highest that we have measured for Calibrated sRGB/Rec.709 and DCI-P3 Gamuts.
See the Screen Reflectance section for the
measurements and details.
· HDR High Dynamic Range Mobile HDR Display
The Pixel 4 XL provides High Dynamic Range Mobile HDR, with support for HDR10,
which allows it to play 4K High Dynamic Range content made for 4K UHD TVs. High Dynamic
Range (HDR) is the newest performance
enhancement feature developed for the latest 4K Ultra HD TVs. HDR provides
expanded the Color, Contrast, and Brightness of video content. In order to
provide Mobile HDR, the Pixel 4 XL has the required Digital Cinema DCI-P3 Wide
Color Gamut, High Peak Luminance, plus perfect Blacks and an Infinite Contrast
Ratio from its OLED display.
· Night Light Mode for Better Night Viewing
The Night Light mode on the Pixel 4 XL is designed to
change the color balance of the display in order to reduce the amount of Blue
light produced by the display, which some recent research indicates can affect
how well users sleep afterwards. In a separate article we
explain and analyze the Blue Light issue for displays. The Pixel 4 XL includes
a user adjustable slider to vary the amount of Blue light produced by the
display, and a timer that allows the Night Light to be turned on and off
automatically every day. The measured variation in the display light spectrum
with the adjustable Night Light slider is shown in this Figure and
below.
As the Night Light
slider setting is increased, the amount of Blue light emitted by the display
decreases. When that happens, White and all screen colors take on an increasing
yellowish tint and color cast. At the Middle setting
the measured White Color Temperature decreases to 4,100
K, and at the Maximum setting it
decreases to 2,700 K, the Color Temperature of
traditional incandescent lighting, which is yellowish. With Night Light at its
Maximum setting, the measured Blue Light component from the Pixel 4 XL is reduced by 80 percent. Turning down the screen
Brightness will further decrease the amount of Blue Light.
Note that as the Night
Light mode changes the White Point of the display from the 6,500 K Standard,
the Absolute Color Accuracy throughout the entire Color Gamut is affected and
reduced. The measured display spectra for several of
the Night Light settings
are included in this Figure and
below.
· Always On Display Mode
The Pixel 4 XL has an Always On
Display mode that takes advantage of the very low power capability of an OLED
display when most of the image pixels are Black, because every sub-pixel is
independently powered, and therefore doesn’t use any power when Black. The
Always On mode is super power efficient and typically requires only a few
percent of the maximum display power. 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
produces an illuminated main screen image 24 hours a day so you can always
discreetly check it with just a glance. It shows the time, date, battery level,
and notifications on the main screen when the phone is off (in standby). The
Brightness (Luminance) depends on the Ambient Light level. The day mode has a
measured Luminance of about 50 cd/m2
(nits) on a Black background, which is very readable but not distracting for
normal indoor ambient lighting, and is visible outdoors if you shade the screen
with your hand. The night mode is entered for very low Ambient Light lux levels
and has a measured Luminance of 3 nits, so it
makes a great Night Clock that won’t disturb you if it’s on your bedside table.
In addition, the Always On Display mode is turned off when it senses a dark
confined space so the battery isn’t wasted in a pocket or pocketbook.
· Super Dim Setting
The Pixel 4 XL also has a Super
Dim Setting 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 provides full 24-bit color and the picture
quality remains excellent.
· Dark Theme
Google has introduced a new Dark
Theme display setting that inverts the typical White Background with
Black Text to a Black Background with White Text. This significantly reduces
the overall Brightness of the entire display for most applications, and should
reduce eye strain when viewing the display in low to dark ambient light. An
additional bonus is that switching to a Black Background will in most cases
significantly reduce the battery power used by the OLED display. For example,
for the Calendar application, at the Maximum Brightness setting, switching to
the Dark Theme reduces the Display Power from 2.4
watts down to 0.4 watts, which will significantly increase the Running
Time on Battery.
· Ambient EQ Viewing Mode
The
Pixel 4 XL Ambient
EQ viewing
mode automatically adjusts the display based on the surrounding color and
lighting conditions, making it easier to view content as the color temperature
adapts to the environment.
The Ambient EQ viewing mode
automatically changes the White Point and color balance of the display based on
real-time measurements of the Ambient Light falling on the screen. The idea is
to make the display behave more like paper reflecting ambient light and taking
on its color. It is implemented with an Ambient Light sensor that measures the
Color of the Ambient Light in addition to its Brightness. Note that as the
display White Point changes from the 6,500 K Standard the Absolute Color
Accuracy throughout the entire Color Gamut is affected and reduced.
· Diamond Sub-Pixels
A Diamond Sub-Pixel layout is used on most Smartphone
OLED displays rather than an RGB Stripe pattern that is used for most LCDs. 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 diamond 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 a Diamond rather than Square or Striped
arrangement of the Sub-Pixels.
· 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 the phone 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 Pixel 4 XL display shows a much smaller 24 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.
All
displays have Color Shifts with Viewing Angle
OLED displays generally
have smaller Color Shifts with Viewing Angle than most LCDs (except for IPS and
FFS based LCD displays). For OLEDs the Color Shifts with Viewing Angle result
primarily from the Cavity Effect that that is
used to increase the Brightness efficiency of the display. The Color Shifts
throughout the Color Gamut then vary as combinations of the Primary Red, Green,
and Blue Color Shifts.
The Color Shift of White, which is the most common
background color is particularly noticeable on many OLED and LCD displays.
The Pixel 4 XL has a
relatively small White Shift of 2.1 JNCD at 30 degrees,
which is unlikely to be noticeable for typical Viewing Angles.
The Color Shift for the Green Primary is 2.4 JNCD at
30 degrees, which is unlikely to be
noticeable for typical Viewing Angles. The Color Shift for the Red Primary is 4.4 JNCD at
30 degrees, which is somewhat larger
than the 3.5 JNCD needed for a Very Good Green rating, and may be noticeable
for some color content but not objectionable.
The Color Shift for the Blue Primary is 4.2 JNCD at
30 degrees. But as explained in our Absolute Color
Accuracy Display Technology Shoot-Out article, the color accuracy of Blue
Region covering the entire range from Cyan to Magenta is generally less
critical for visual color accuracy. While the eye can still detect color
differences and color errors in the Blue Region, for the most part we are less
likely to notice or be troubled by color differences and discrepancies with
colors in the Blue Region. So a larger Blue Color Shift is less noticeable than
the Red and Green Color Shifts found in many Smartphone displays.
See the Viewing Angles section for the measurements and
details.
· Viewing Tests Performance
The Pixel 4 XL provides very nice, pleasing and very
accurate colors and picture quality. 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 Pixel 4 XL excels due to its impressive Absolute
Color Accuracy (0.5 JNCD), which is Visually
Indistinguishable from Perfect, and is very likely considerably better
than any mobile display, monitor, TV or UHD TV that you have. So photos, videos,
and online content and merchandise will appear correct and beautiful. See the Color Accuracy Figures
and the Colors and Intensities section for
quantitative details.
· Display Power Efficiency
The Display’s Power Efficiency is extremely important for
Battery Running Time because the display can use up to 60%
of the Total Pixel 4 XL Power for an all White Screen at the Maximum
Brightness setting. For Maximum Brightness and Display Power the Pixel 4 XL has
a 6% higher Display Power Efficiency compared
to the Pixel 3 XL.
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 or dark 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 70
percent or less, and LCDs are more power efficient for Average Picture Levels
above 70 percent. Since both technologies are continuing to improve their power
efficiencies, the crossover will continue to change with time. See the Display Power section for the measurements and
details.
· Display Related Enhancements
· The Pixel 4 XL has a water
protection rating of IP68, which means you can
comfortably view the display in typical wet indoor and outdoor conditions –
even carefully use it in a tub or shower, and it should be fine if you
accidentally drop it in a sink or toilet. Note that water resistance may be
reduced over time from normal wear and tear.
· The Pixel 4 XL can be used with Polarized Sunglasses in both the Portrait and
Landscape orientations unlike many LCDs, which generally work in only one of
the two orientations.
· The Pixel 4 XL has Gorilla Glass 5, which provides much higher
resistance to scratching and breakage.
Pixel 4 XL Conclusions:
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.
Summary of the Pixel 4 XL Display
Functions, Features, and Performance Records:
The Pixel 4 XL has many major and important
state-of-the-art display performance enhancements, features and functions,
including a number of Display Performance Records,
which are summarized below.
See the Display Shoot-Out Comparison
Table section below for the complete DisplayMate Lab measurements and test
details.
See the Display Highlights and
Performance Results section above for a detailed overview with expanded
discussions and explanations.
See the Display Assessments
section for the evaluation details.
The Pixel 4 XL has the following
State-of-the-Art Display Performance Functions and Features:
· A
state-of-the-art OLED display that is
manufactured on a flexible plastic substrate. While
the OLED display itself is flexible, the screen remains rigid under an outer
hard cover glass.
· A Full Screen design
with a large 6.3 inch
OLED display that fills almost the entire
front face of the Pixel 4 XL from edge-to-edge, providing a
significantly larger display for the same phone size.
· A display form factor with a taller height to width Aspect Ratio of 19 : 9 = 2.11, which is 19% larger than the 16 : 9 = 1.78 on most
Smartphones (and widescreen TVs) because the display now has the same overall
shape as the entire phone. It is taller in Portrait mode and wider in Landscape
mode.
· A 3K High Resolution 3040 x 1440 Quad HD+ Display with 537 pixels per inch, and Diamond
Sub-Pixels with Sub-Pixel Rendering for
enhanced sharpness and higher Peak Brightness.
· The Pixel 4
XL display appears Perfectly Sharp for normal 20/20
Vision at Typical Smartphone Viewing Distances of 12 to 18 inches (30 to 46
cm).
· A Full Screen Peak Brightness of 444
nits for 100% APL, which improves screen visibility in high Ambient
Light.
· Peak Brightness that is Independent
of the on-screen Image Content.
· Each Pixel 4 XL display is individually calibrated at the
factory for both Color Accuracy and Contrast Accuracy.
· Very High Absolute Color Accuracy (0.5 JNCD) that is
Visually Indistinguishable From Perfect.
· Very High
Image and Picture Contrast Accuracy and Intensity Scale Accuracy (2.19
Gamma) that is Visually Indistinguishable From Perfect.
· Color Accuracy and
Intensity Scales that are Independent of the Image Content APL.
· Automatic Color Management that automatically switches to the proper Color Gamut for
any displayed image content within the Wide DCI-P3 Color Space that has an ICC
Profile, so images automatically appear with the correct colors, neither being
over-saturated or under-saturated.
· 2 Industry Standard Color Gamuts: the sRGB / Rec.709 Color
Gamut that is used for most current consumer
content, and the new Wide DCI-P3 Color Gamut that is used in 4K Ultra HD TVs. The DCI-P3 Gamut is
26 percent larger than the sRGB / Rec.709 Gamut.
· A full 100% DCI-P3
Color Gamut that is also used for 4K Ultra
HD TVs, so the Pixel 4 XL can display the latest high-end 4K video
content.
· A High Dynamic Range Mobile HDR
Display which allows the Pixel 4 XL to play 4K High Dynamic Range content
produced for 4K UHD TVs.
· A Very Low Screen Reflectance
of 4.4 percent.
· An Always On Display with day and night modes.
· A Night Light Mode that
allows the user to adjust and reduce the amount of Blue Light from the display
for better night viewing and improved sleep.
· A Dark Theme setting that
inverts the typical White Background with Black Text to a Black Background with
White Text, which significantly reduces the overall Brightness of the entire
display for most applications, and should reduce eye strain when viewing the
display in low to dark ambient light.
· An Ambient
EQ viewing mode that automatically changes the White Point and color
balance of the display based on real-time measurements of the Ambient Light
falling on the screen to make the display behave more like paper reflecting
Ambient Light and taking on its color.
· Small to Medium Color Shifts and Small Brightness Shifts with Viewing Angle.
· Vision Accessibility Display Modes to help people
with vision impairments.
· The Pixel 4 XL
can be used with Polarized Sunglasses in both the
Portrait and Landscape orientations unlike many LCDs, which generally work in
only one of the two orientations.
The Pixel 4
XL matches or sets new Smartphone Display Performance Records for:
Note that Numerical Performance
Differences that are Visually Indistinguishable are considered Matched and Tied
Performance Records.
· Highest Absolute Color Accuracy (0.5 JNCD) – Visually Indistinguishable From Perfect.
· Highest Image
Contrast Accuracy and Intensity Scale Accuracy (2.19 Gamma) – Visually Indistinguishable From Perfect.
· Smallest Shift in Color
Accuracy with the Image Content APL (0.2 JNCD) – Visually Indistinguishable From Perfect.
· Smallest Shift in Image
Contrast and Intensity Scale with the Image Content APL (0.01 Gamma) – Visually Indistinguishable From Perfect.
· Smallest Change in Peak Luminance with the Image Content Average
Picture Level APL (1 percent) – Visually
Indistinguishable From Perfect.
· Highest Contrast Ratio (Infinite).
· Lowest Screen Reflectance (4.4 percent).
· Smallest Brightness Variation with Viewing Angle (24% at 30
degrees).
· Highest Visible Screen Resolution 3K (3040x1440) – 4K Does Not appear visually sharper on a Smartphone.
DisplayMate
Best Smartphone Display Award
OLED has evolved into a highly refined and mature display technology that
now produces the best and highest performance displays for Smartphones.
OLED Display Performance continues to
provide major Record Setting improvements with every new generation.
With consumers now spending
rapidly increasing amounts of time watching content on their Smartphones, the
shift in emphasis from primarily improving Display Hardware Performance to
enhancing the overall Display Picture Quality and Color Accuracy is an
important step that DisplayMate Technologies has been pushing for many years in
our Display
Technology Shoot-Out article series, so it is great to see
manufactures improving and then competing on these metrics.
The Pixel 4 XL has a Very Impressive Top Tier Display with
close to Text Book Perfect Calibration and Performance!
Google has continued to
raise the on-screen Absolute Picture Quality
and Absolute Color Accuracy of their displays
by implementing Precision Factory Display Calibration,
moving the overall Pixel 4 XL display performance up to Record Setting Outstanding levels,
and setting or matching many Display Performance
Records, including Absolute Color Accuracy
at a very impressive 0.5 JNCD that is Visually Indistinguishable From Perfect, and almost certainly considerably better than your existing
Smartphone, 4K UHD TV, Tablet, Laptop and computer monitor. Compared to
the Pixel 3 XL, the Pixel 4 XL has a number of notable improvements including 10% higher Peak Brightness, much higher Absolute Color
Accuracy, and improved Display Power Efficiency.
The Pixel 4 XL delivers
uniformly consistent all around Top Tier
display performance and receives All Green (Very Good
to Excellent) Ratings in all of the DisplayMate Lab Test and Measurement
Categories except Yellow (Good) for larger Color Shifts at 30 degrees Viewing Angle (4.2 JNCD
and 4.4 JNCD).
See the links below for all of the measurements, analysis
and assessments:
Data Tables: See
the Display Shoot-Out Lab Measurements Comparison Table
section below for all of the measurements and details.
Highlights: See
the Display Highlights and Performance Results
section above for expanded discussions and explanations.
Features: See the Display Performance Functions and Features
section above.
Records: See
the Display Performance Records section above.
Assessments: See
the Display Assessments section below for the
evaluation details.
Based on our extensive Lab
Tests and Measurements the Pixel 4 XL receives our DisplayMate Best Smartphone Display Award earning DisplayMate’s highest ever A+ grade by providing
considerably better display performance than other competing Smartphones.
Top Tier of Smartphone
Displays
The Pixel 4 XL
joins the very select Top Tier of Smartphone
Displays which all provide Close to Text
Book Perfect Calibration Accuracy and Performance that is Visually Indistinguishable From Perfect, so they received and maintain Concurrent DisplayMate Best Smartphone Display Awards. All are Excellent State-of-the-Art Displays, each is
better in some Display Performance Categories, but None are Best in All the
Display Performance Categories. Note that measured numerical display
performance differences that are Visually Indistinguishable are equivalent.
As Display Performance continues
to improve we have and will continue to raise the Performance Levels necessary
to receive a DisplayMate Best Smartphone Display Award, so the Top Tier of Smartphone Displays will continue to evolve and change with each new generation.
OLED
displays now have tremendous performance advantages over LCDs, so high-end and
flagship Smartphones need OLED displays in order to compete at state-of-the-art
performance levels, securing OLED as the definitive premier display technology
for Top Tier Smartphones in the foreseeable future over the next 3-5 years. With
the continuing improvements in OLED hardware performance, picture quality, and
precision accuracy, it will be much harder for new display technologies to
challenge OLED.
Follow DisplayMate
on Twitter to learn about our upcoming Smartphone display technology
coverage.
Improving the
Next Generation of Mobile Displays
The Pixel 4 XL has a very
high resolution 3K 3040x1440 pixel display with 537 pixels per inch (ppi)
producing images that look perfectly sharp with normal 20/20 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. Some clueless reviewers have been pining for 4K 3840x2160
Smartphones, which would require almost double the pixels, memory, and
processing power of the 3040x1440 display on the Pixel 4 XL, but there would be
no visual benefit for humans! 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 no visual benefit for humans!
Improving Display Performance
for Real World Ambient Light Viewing Conditions
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 due to ambient light, something that every
consumer will benefit from, and will also immediately notice and appreciate –
providing a true sales and marketing advantage…
Currently all existing displays
are Accurate only when viewed in Absolute Darkness 0 lux. The most
important improvements for 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, Reduced Color Saturation, and Reduce Color Accuracy. The key will be in lowering the Screen Reflectance and implementing Dynamic Color Management with automatic real-time
modification of the display’s native Color Gamut and Dynamic
Intensity Scales based on the measured Ambient Light level in order to
have them compensate for the reflected light glare and image wash out that
causes a loss of color saturation and image contrast from ambient light as
discussed in our 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.
|
Pixel 4 XL
|
Pixel 4 XL Display Shoot-Out Lab
Measurements Comparison Table
Below we
examine in-depth the OLED display on the Google Pixel
4 XL based on objective Lab measurement
data
and
criteria in the following sections: Display
Specifications, Overall Assessments, Screen Reflections, Brightness
and Contrast,
Colors and Intensities, Absolute Color Accuracy, Viewing
Angles, OLED Spectra, Display
Power.
For
additional background information see this earlier article covering the Flagship OLED
2017 Smartphones.
Detailed Test and Measurement Comparisons between
the Pixel 4 XL, the Pixel 3 XL, and the Galaxy Note10+ Displays
You can directly compare the data and measurement results
for the Pixel 4 XL with the Pixel 3 XL and Galaxy Note10+ 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 is easy to make detailed side-by-side comparisons
by simply clicking through the Tabs.
Google Pixel 4 XL Lab Measurements Comparison Table
Google Pixel
3 XL Lab Measurements Comparison Table
Samsung
Galaxy Note10+ 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
|
Google
Pixel 4 XL
|
Comments
|
|
Display Technology
|
Flexible
OLED Display with Diamond Sub-Pixels
6.3 inch
Diagonal / 15.9 cm Diagonal
Excluding
the Rounded Corners
|
Flexible Organic Light Emitting Diode
Diamond Sub-Pixels with Diagonal Symmetry.
|
|
Screen Shape
|
19 : 9 =
2.11
New Higher
Aspect Ratio
Most
Smartphones and Widescreen TVs have 16 : 9 = 1.78
|
Height to Width Aspect Ratio
Pixel 4 XL display screen is 19% longer
than
most Smartphones and widescreen 16:9 TV
content.
|
|
Screen Size
|
2.68 x
5.66 inches
6.81 x
14.38 cm
|
Display Width and Height in inches and
cm.
|
|
Screen Area
|
15.2 square inches / 98
square cm
Excluding
the Rounded Corners
|
A better measure of size than the
diagonal length.
|
|
Supported Color Gamuts
|
Wide Gamut
– DCI-P3 Digital Cinema Color Gamut
Standard
Gamut – sRGB / Rec.709 Standard Color Gamut
|
The Pixel 4 XL supports 2 Color Gamuts
including
the new wider DCI-P3 Color Gamut that is
used in the 4K Ultra HD TV content.
|
|
Display Resolution
|
3040 x 1440
pixels
3K Quad
HD+
|
Screen Pixel Resolution.
Quad HD can display four 1280x720 HD
images.
|
|
Total Number of Pixels
|
4.4 Mega
Pixels
|
Total Number of Pixels.
|
|
Pixels Per Inch
|
537 PPI
with Diamond Sub-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
380 SPPI
Green
537 SPPI
Blue
380 SPPI
|
Diamond Sub-Pixel displays have only half
the number
of Red and Blue Sub-Pixels as RGB Stripe
displays.
See Diamond
Sub-Pixels
|
|
Total Number of Sub-Pixels
|
Red
2.2 Million Sub-Pixels
Green 4.4
Million Sub-Pixels
Blue
2.2 Million Sub-Pixels
|
Number of Mega Sub-Pixels for Red,
Green, Blue.
Diamond Sub-Pixel displays have only half
the number
of Red and Blue Sub-Pixels as RGB Stripe
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
|
6.4 inches / 16.3 cm for White and Green Sub-Pixels with 20/20 Vision
9.1
inches / 23.0 cm 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.
|
|
Display Sharpness
at Typical Viewing Distances
|
Pixel 4 XL Display
appears Perfectly Sharp
Pixels are
not Resolved with 20/20 Vision
at Typical
Viewing Distances of
12 to
18 inches
30 to 46
cm
|
The Typical Viewing Distances for this
screen size
are in the range of 12 to 18 inches or
30 to 46 cm.
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 12 to 18
inches
or 30 to 46 cm for this screen size.
|
|
Photo Viewer Color Depth
|
Full
24-bit Color
No
Dithering Visible
256
Intensity Levels
|
Some Smartphones and Tablets still have
some
form of 16-bit color depth in the
Gallery Viewer.
The Google Pixel 4 XL 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
Pixel 4 XL Color Management automatically switches to the appropriate Color
Gamut for the current on-screen content.
Note
that all of the tests and measurements are with the Natural
Color Mode which provides the Highest Accuracy.
The
DCI-P3 Digital Cinema Gamut is used in 4K Ultra HD TVs, and other advanced imaging
applications.
The
sRGB / Rec.709 Gamut is used for most current consumer photo, video,
web, and computer content.
|
Categories
|
Wide
Gamut
DCI-P3
Digital Cinema
|
Standard
Gamut
sRGB /
Rec.709 Content
|
Comments
|
|
Viewing Tests
in Subdued Ambient Lighting
|
Excellent
Images
Photos and
Videos
have
Excellent Color
and
Accurate Contrast
Accurate
Wide Gamut
|
Excellent
Images
Photos and
Videos
have
Excellent Color
and Accurate
Contrast
Accurate
Standard Gamut
|
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 to
Medium Color Shifts
with
Viewing Angle
Small
Brightness Shifts
with
Viewing Angle
|
Small to
Medium Color Shifts
with
Viewing Angle
Small
Brightness Shifts
with
Viewing Angle
|
The Pixel 4 XL 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
Accurate
Wide Gamut
|
Excellent
OLED Display
Accurate
Standard Gamut
|
The Pixel 4 XL OLED Display performed
very well in the Lab Tests and
Measurements.
|
|
|
|
Absolute Color Accuracy
Measured over Entire Gamut
See Figure 2 and Colors
|
Excellent
Color Accuracy
Color
Errors are Very Small
Accurate
Wide Gamut
|
Excellent
Color Accuracy
Color
Errors are Very Small
Accurate
Standard Gamut
|
Absolute
Color Accuracy is measured with a
Spectroradiometer
for 41
Reference Colors
uniformly
distributed within the entire Color Gamut.
See
Figure 2 and Colors for details.
|
|
Image Contrast Accuracy
See Figure 3 and Contrast
|
Excellent
Accuracy
Image
Contrast
Very
Accurate
|
Excellent
Accuracy
Image
Contrast
Very
Accurate
|
The
Image Contrast Accuracy is determined by
measuring
the Log Intensity Scale and Gamma.
See
Figure 3 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
|
High
Display Brightness
Very Low
Reflectance
High
Contrast Rating
for Ambient
Light
|
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
|
Excellent
Calibration
Accurate
Wide Gamut
|
Excellent
Calibration
Accurate
Standard Gamut
|
Pixel 4 XL display delivers accurately
calibrated
colors and images for both the Wide
Gamut and
the Standard Gamut.
|
|
|
Overall Display Grade
Overall
Assessment
|
Overall Pixel 4 XL Display
Grade is Excellent A+
DisplayMate Best
Smartphone Display Award
An Excellent Top Tier
World Class Smartphone Display
Major Display
Performance Improvements to the Pixel 3 XL
|
The Pixel 4 XL display delivers excellent
image quality, has both Wide Color Gamut
and Standard Color Gamut modes, with
high Screen Brightness and low
Reflectance,
has good Viewing Angles, and is an all
around
top performing Smartphone display.
|
|
Accurate
Wide Gamut
For Viewing
4K UHD TV
DCI-P3
Cinema Content
|
Accurate
Standard Gamut
For Viewing
Most Content
Photo Video
Movie Web
|
Categories
|
Wide
Gamut
DCI-P3
Digital Cinema
|
Standard
Gamut
sRGB /
Rec.709 Content
|
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.
We use an Integrating Hemisphere and a
highly collimated pencil light beam together with a Spectroradiometer.
Note the Screen
Reflectance is exactly the same for both Color Gamuts.
The Pixel 4 XL has one of the lowest
Screen Reflectance levels that we have ever measured for a Smartphone.
These results are extremely important
for screen readability, picture quality, and color accuracy in ambient light.
|
Categories
|
Pixel 4
XL
|
Comments
|
|
Average Screen Reflection
Light From All Directions
|
4.4 percent
for
Ambient Light Reflections
Excellent
|
Measured using an Integrating Hemisphere
and
a Spectroradiometer.
The lowest value we have ever measured
for a Smartphone is 4.3 percent.
|
|
Mirror Reflections
Percentage of Light Reflected
|
5.7
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.
The lowest value we have ever measured
for a Smartphone is 5.4 percent.
|
|
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.
|
Categories
|
Wide
Gamut
DCI-P3
Digital Cinema
|
Standard
Gamut
sRGB /
Rec.709 Content
|
Comments
|
|
Home Screen Peak Brightness
Measured for White
|
Brightness
444 cd/m2
Very Good
|
Brightness
444 cd/m2
Very Good
|
The Peak Brightness for White on the
Home Screen.
Varies with the Wallpaper selected.
|
|
Measured Average Brightness
50% Average Picture Level
|
Brightness
445 cd/m2
Very Good
|
Brightness
446 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
442 cd/m2
Very Good
|
Brightness
446 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% Average Picture Level
|
Brightness
445 cd/m2
Very Good
|
Brightness
448 cd/m2
Very Good
|
This is the Peak Brightness for a screen
that
has only a tiny 1% Average Picture
Level.
|
|
Dynamic Brightness
Change in Luminance with
Average Picture Level
|
1 percent
Decrease
Excellent
|
0.5
percent Decrease
Excellent
|
This is the percent Brightness decrease
with APL,
Average Picture Level. Ideally should be
0 percent.
|
|
Low Ambient Light
|
|
Lowest Peak Brightness
Super Dim Setting
Brightness Slider to Minimum
|
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 remains
Excellent.
|
|
Black Brightness at 0 lux
at Maximum Brightness Setting
|
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
|
Only relevant for Low Ambient Light,
which is seldom the case for mobile
devices.
|
|
High Ambient Light
|
|
Measured Auto Brightness
in High Ambient Light
with Automatic Brightness On
|
Auto
Brightness
in High
Ambient Light
442 – 445
cd/m2
Very Good
|
Auto Brightness
in High
Ambient Light
446 – 448
cd/m2
Very Good
|
The Maximum Brightness is the same
for both the Manual and Auto Brightness
modes.
|
|
Contrast Rating
for High Ambient Light
The Higher the Better
for Screen Readability
in High Ambient Light
|
100 – 101
Very Good
|
101 – 102
Very Good
|
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
|
Excellent:
A
|
Excellent: A
|
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.
The Pixel 4 XL Color Management
automatically switches to the appropriate Color Gamut for the current
on-screen content.
|
Categories
|
Wide
Gamut
DCI-P3
Digital Cinema
|
Standard
Gamut
sRGB /
Rec.709 Content
|
Comments
|
|
Color of White
Color Temperature in degrees
Measured in the dark at 0 lux
See Figure 1
|
6,610 K
0.4 JNCD
from D65 White
Very Close
to Standard
Accurate
Wide Gamut
See Figure 1
|
6,640 K
0.5 JNCD
from D65 White
Very Close
to Standard
Accurate
Standard Gamut
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
|
102 percent
DCI-P3
Cinema Gamut
with Natural Color Mode
Very Close
to Standard
Accurate
Wide Gamut
108 percent
DCI-P3
Cinema Gamut
with Boosted Color Mode
Intentionally
Over Saturated
See Figure 1
|
103 percent
sRGB /
Rec.709 Gamut
with Natural Color Mode
Very Close
to Standard
Accurate
Standard Gamut
119 percent
sRGB /
Rec.709 Gamut
with Boosted Color Mode
Intentionally
Over Saturated
See Figure 1
|
Most current consumer content uses sRGB /
Rec.709.
The new 4K UHD TVs and Digital Cinema use
DCI-P3.
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.
See Figure 1
|
|
Absolute Color Accuracy
|
|
Absolute Color Accuracy
Natural Color Mode
Average Color Error at 0 lux
For 41 Reference Colors
Just Noticeable Color Difference
See Figure 2
|
Average
Color Error
From
DCI-P3
Δ(u’v’)
= 0.0018
0.5 JNCD
with Natural Color Mode
Excellent
Color Accuracy
Accurate
Wide Gamut
See Figure 2
|
Average
Color Error
From sRGB
/ Rec.709
Δ(u’v’)
= 0.0018
0.5 JNCD
with Natural Color Mode
Excellent
Color Accuracy
Accurate
Standard Gamut
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.
Color Errors below 3.5 JNCD are Very
Good.
Color Errors 3.5 to 7.0 JNCD are
Good.
Color Errors above 7.0 JNCD are
Poor.
|
|
Absolute Color Accuracy
Natural Color Mode
Largest Color Error at 0 lux
For 41 Reference Colors
Just Noticeable Color Difference
See Figure 2
|
Largest Color Error
From
DCI-P3
Δ(u’v’)
= 0.0056
1.4 JNCD
for 100%
Cyan-Blue
with Natural Color Mode
Excellent
Accuracy
Accurate
Wide Gamut
See Figure 2
|
Largest Color Error
From sRGB
/ Rec.709
Δ(u’v’)
= 0.0082
2.1 JNCD
for 100%
Red
with Natural Color Mode
Very Good
Accuracy
Accurate
Standard Gamut
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.
Color Errors below 3.5 JNCD are Very
Good.
Color Errors 3.5 to 7.0 JNCD are
Good.
Color Errors above 7.0 JNCD are
Poor.
|
Shifts in Absolute Color Accuracy with Average Picture Level APL
Shifts in Absolute Color Accuracy with
Image Content from Low 1% APL to High 50% APL
|
|
Shift in the Color of White
Natural Color Mode
Just Noticeable Color Difference
See Figure 4
|
White Point
Color Shift
from Low
to High APL
Δ(u’v’)
= 0.0009
0.2 JNCD
Excellent
See Figure 4
|
White Point
Color Shift
from Low
to High APL
Δ(u’v’)
= 0.0008
0.2 JNCD
Excellent
See Figure 4
|
JNCD is a Just Noticeable Color Difference
See Figure 2 for the
definition of JNCD.
See Figure 4 for the
measured Color Shifts.
Color Shifts below 3.5 JNCD are Very
Good.
Color Shifts 3.5 to 7.0 JNCD are
Good.
Color Shifts above 7.0 JNCD are
Poor.
|
|
Average Color Shift
Natural Color Mode
For 41 Reference Colors
Just Noticeable Color Difference
See Figure 4
|
Average
Color Shift
from Low
to High APL
Δ(u’v’)
= 0.0008
0.2 JNCD
Excellent
See Figure 4
|
Average
Color Shift
from Low
to High APL
Δ(u’v’)
= 0.0009
0.2 JNCD
Excellent
See Figure 4
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD.
See Figure 4 for the
measured Color Shifts.
Color Shifts below 3.5 JNCD are Very
Good.
Color Shifts 3.5 to 7.0 JNCD are
Good.
Color Shifts above 7.0 JNCD are
Poor.
|
|
Largest Color Shift
Natural Color Mode
For 41 Reference Colors
Just Noticeable Color Difference
See Figure 4
|
Largest Color Shift
from Low
to High APL
Δ(u’v’)
= 0.0015
0.4 JNCD
for 50% Red
Excellent
See Figure 4
|
Largest Color Shift
from Low
to High APL
Δ(u’v’)
= 0.0021
0.5 JNCD
for 75%
Magenta-Red
Excellent
See Figure 4
|
JNCD is a Just Noticeable Color Difference
See Figure 2 for the
definition of JNCD.
See Figure 4 for the
measured Color Shifts.
Color Shifts below 3.5 JNCD are Very
Good.
Color Shifts 3.5 to 7.0 JNCD are
Good.
Color Shifts above 7.0 JNCD are
Poor.
|
|
Intensity Scale and Image Contrast Accuracy
|
|
Intensity Scale and
Image Contrast
See Figure 3
|
Very
Smooth and Straight
Excellent
Very
Accurate
See Figure 3
|
Very
Smooth and Straight
Excellent
Very
Accurate
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
|
Gamma 2.19
Excellent
Gamma Very
Accurate
|
Gamma 2.19
Excellent
Gamma Very
Accurate
|
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
|
Excellent
|
Excellent
|
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 Pixel 4 XL display has a
Brightness (Luminance) fall off with Viewing Angle that is much smaller than
the best LCD displays.
The Pixel 4 XL has a
relatively small White Shift of 2.1 JNCD at 30
degrees, which is unlikely to be noticeable for typical Viewing
Angles.
The Color Shift for the Green Primary is 2.4 JNCD
at 30 degrees, which is unlikely to
be noticeable for typical Viewing Angles.
The Color Shift for the Red Primary is 4.4 JNCD at 30 degrees, which may be noticeable for
some color content but not objectionable.
The Color Shift for the Blue Primary is 4.2 JNCD
at 30 degrees. Blue Color Shifts are less
visually noticeable than the
Red
and Green Color Shifts found in many Smartphone displays. See the Viewing Angle section for details.
Note
that for 2019 we now list the Color Shifts for each individual Primary Color
instead of only listing the Maximum Color Shift,
which
had up to a higher 5.0 JNCD threshold for receiving a Very Good Green Rating.
With this new metric all current model
OLED
Smartphone Displays that we have tested would receive a Yellow Rating for at
least one Primary Color.
|
Categories
|
Wide
Gamut
DCI-P3
Digital Cinema
|
Standard
Gamut
sRGB /
Rec.709 Content
|
Comments
|
|
Brightness Decrease
at a 30 degree Viewing Angle
|
24 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’)
= 0.0084 Shift towards Blue
2.1 JNCD
Very Good
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD.
Color Shifts below 3.5 JNCD are Very
Good.
|
|
Color Shifts for the Primaries
|
|
Red Primary Color Shift
at a 30 degree Viewing Angle
|
Medium
Color Shift
Δ(u’v’)
= 0.0177
4.4 JNCD
Good
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD.
Color Shifts 3.5 to 7.0 JNCD are
Good
|
|
Green Primary Color Shift
at a 30 degree Viewing Angle
|
Small Color
Shift
Δ(u’v’)
= 0.0097
2.4 JNCD
Very Good
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD.
Color Shifts below 3.5 JNCD are Very
Good.
|
|
Blue Primary Color Shift
at a 30 degree Viewing Angle
|
Medium
Color Shift
Δ(u’v’)
= 0.0167
4.2 JNCD
Good
|
JNCD is a Just Noticeable Color Difference.
See Figure 2 for the
definition of JNCD.
Color Shifts 3.5 to 7.0 JNCD are
Good.
|
|
|
|
Color Shifts for Color Mixtures
at a 30 degree Viewing Angle
Reference Brown (255, 128, 0)
|
Small
Color Shift
Δ(u’v’)
= 0.0109
2.7 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 Spectra
The Display Spectra for the Pixel 4 XL
including the Night Light mode are measured in Figure 5 below.
The Night Light
mode is designed to change the color balance of the display in order to
reduce the amount of Blue Light
produced by the display,
which some recent research indicates can affect how well users sleep
afterwards.
The measured display
spectra for several of the Night Light settings
are included in Figure 5b.
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 can have different screen sizes
and maximum brightness, the display power values below are 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 70 percent or
less, and
LCDs are more power efficient
for Average Picture Levels above 70 percent.
Since both technologies are continuing to improve their
power efficiencies, the crossover will continue to change with time.
For OLEDs the Display Power
depends on the Picture Content.
An entirely Black OLED Screen
uses 0 watts of Display Power.
For Maximum Brightness and
Display Power the Pixel 4 XL has a 6% higher Relative Display Power
Efficiency
compared to the Pixel 3 XL.
When the display is at Full
Screen White at Maximum Brightness the display uses 60% of the total Pixel 4
XL power,
so the display settings are a
major factor in the Battery Running Time.
|
Categories
|
Pixel
3 XL
|
Pixel
4 XL
|
Comments
|
|
Average Display Power
Maximum Brightness at
50% Average Picture
Level
|
50%
Average Picture Level
1.05
watts
with 416
cd/m2
15.2 inch2
Screen Area
|
50%
Average Picture Level
1.10
watts
with 446
cd/m2
15.2 inch2
Screen Area
|
This measures the Average Display
Power for
a typical range of image content.
|
|
Relative Power Efficiency
50% Average Picture Level
Compared to Pixel 3 XL
For the same 416 cd/m2
For the same Screen Area
|
Relative Average Power 100%
1.05 watts
with the same 416
cd/m2
with the same 15.2 inch2
Screen Area
|
Relative Average Power 93%
0.98 watts
with the same 416
cd/m2
with the same 15.2 inch2
Screen Area
|
This compares the Relative Power Efficiency
by scaling the measured Display Power to the
same Screen Brightness and same Screen Area
as the Pixel 3 XL.
|
|
|
|
Maximum Display Power
Full White Screen
at Maximum Brightness
|
Maximum
Power
Full
Screen White
2.10
watts
with
405 cd/m2
15.2 inch2
Screen Area
|
Maximum
Power
Full
Screen White
2.15 watts
with
446 cd/m2
15.2 inch2
Screen Area
|
This measures the Maximum Display
power for
a screen that is entirely Peak White.
|
|
Relative Power Efficiency
Maximum Display Power
Compared to Pixel 3 XL
For the same 405 cd/m2
For the same Screen Area
|
Relative Maximum Power 100%
2.10 watts
with the same 405
cd/m2
with the same 15.2 inch2
Screen Area
|
Relative Maximum Power 94%
1.97 watts
with the same 405
cd/m2
with the same 15.2 inch2
Screen Area
|
This compares the Relative Power Efficiency
by scaling the measured Display Power to the
same Screen Brightness and same Screen Area
as the Pixel 3 XL.
|
|
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.
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Article Links: Google
Pixel 3 XL OLED Display Technology Shoot-Out
Article Links: Samsung
Galaxy Note10+ OLED Display Technology Shoot-Out
Article Links: Display
Color Gamuts Shoot-Out NTSC to Rec.2020
Article Links: Absolute
Color Accuracy Display Technology Shoot-Out
Article Links: Watching
Displays at Night
Article Links: Display Technology Shoot-Out
Article Series Overview and Home Page
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