Give me a data set and I’ll comb through it for trends, outliers, winners and losers. In this post, I’m going to focus on televisions. The Rtings testers were kind enough to provide me with data from over 300 TVs over the past five years. These can be used to examine trends over time, by manufacturer and also by TV type. Rtings collects various data on all tested televisions and monitors. However, today I will only focus on two metrics within the TV category: the color and brightness of TV displays.
I’m talking about the DCI-P3 and REC 2020 color spaces. For REC 2020, the displays need extremely rich primary colors with very narrow spectra, which are actually only provided by laser light sources. I asked almost three years ago whether displays achieve this enormous color range at all be able. I want to check that with the new data.
I can’t comment on the accuracy of the data or measurements, although I do Rtings generally believe to be a reliable and unbiased source of data. For more detailed information on Rtings measurements, visit their website. Also, this is by no means a comprehensive data set. While 300+ data points is a lot, there are many more TVs out there, especially in different parts of the world. (pp)
Color spaces per display technology
I divided the Rtings data into three types of TVs, namely LCD, OLED and QLED, the latter being LCD with color-enhancing quantum dots. QD-OLED, on the other hand, falls into the OLED category, but I’ve used a triangle in the graphs to separate the two data points for Samsung’s S95B and Sony’s A95K (these are the two currently available TVs with Samsung’s QD-OLED panel) . I also sorted the data by manufacturer and assigned different colors to them in the graphic. In this way, the trends over time within the panel technologies and also for each manufacturer can be viewed.
Since I am particularly interested in televisions with a large color space, I have grayed out the part of the graphic in which the xy color space is above 90% DCI-P3 (left). I also analyzed the measured color range (the gamut) in the REC 2020 color space (right) and also marked the area above 90% in gray here. More than 90 percent of REC 2020 is an ambitious goal that none of the measured TVs (so far) achieves. Take a minute for the graphics.
Measured color gamut (defined as a percentage of DCI-P3 and REC 2020) over the years by display type and manufacturer.
trend analysis
Have you noticed how tightly the OLED data is grouped and that all OLED TVs since 2016 fall into the WCG (Wide Color Gamut) category with more than 90% DCI-P3? And that the color gamut has steadily increased every year (see Sony dataset in yellow).
LCD specs appear to vary significantly and are highly dependent on manufacturer, with data points ranging from under 65% coverage to over 90% DCI-P3. However, this data mixes budget LCDs with high-end models, so the spread isn’t too surprising.
The QLED data is interesting: almost all fall into the WCG category >90% DCI-P3. The exception comes from Samsung, where about half of the data points have stayed just below that mark in recent years.
The trends (but not the absolute values) in the REC 2020 color space are similar to those for DCI-P3, with the two QD-OLED models reaching almost the 90 percent range of REC 2020. The other OLEDs, on the other hand, are around 70 to 75 percent
I’m a “visual learner” and probably looked at the data a few dozen different ways. I thought the following gamut graph was worth sharing.
Measured color gamut (defined as percentage of DCI-P3 and REC 2020) including all manufacturers. Analysis by TV type.
Colorful quantum dots
It turns out that the OLEDs and the more powerful QLEDs cover the DCI-P3 color space very well (>95% in many cases, upper half of the chart). However, if we look at REC 2020 (bottom half of the chart), the QLEDs tend to perform better than OLEDs. It’s no surprise that the two QD-OLEDs in the REC 2020 cover outperform all others.
I’m assuming this measurement was done in such a way that the display doesn’t have to map the color space to a smaller color space (see my post from earlier this year: Give me back my gamut, QD OLED!. Quantum dots are able to achieve better coverage of the REC 2020 color space because of their continuously tunable, narrow emission spectrum that can be optimized for different color spaces. In contrast, OLEDs have a fixed emission spectrum with discrete options for tunability.
More light
RTings does a whole bunch of brightness measurements, which I won’t go into detail about here. I chose the “Real Scene” brightness measurement because I find this measurement most accurately reflects how many people use their TVs. After all, not everyone has a dark basement cinema with black seats and black paint on the walls where they watch movies on their OLED TV. Here are the results for more realistic environments broken down by TV type over the last six years.
Measured “Real Scene” brightness by TV type from 2017 to 2022.
The box and whisker diagram may not be familiar to everyone. The chart type includes five metrics (minimum, maximum, 1st quartile, median, and 3rd quartile). Its name comes from the English (beard hair, whisker hair) and refers to the appearance of the diagram. A compact explanation can be found here, for example: Box whiskers plot.
The main things I see in the graph are:
LCD and QLED (i.e. LCDs with colour-enhancing quantum dots) have a very large brightness control range. In the last two years some QLEDs have reached over 1000 cd/m2 (nits). In general, the outliers tend to be on the high side. Note that $250 TVs were evaluated here along with $2000 TVs. I’m assuming that the few high-brightness TVs are the more expensive ones, and RTINGS tested relatively few of them – probably because each brand only offers one or two high-end TVs a year, but dozens of cheaper models.
OLED grouping is very good, but brightness is (no surprise) not that great. This has been a disadvantage of OLEDs for years. 2022 is looking better than previous years, thanks in part to the two QD-OLEDs in this category, as well as advances LG has made such as including deuterium to improve brightness/reliability.
Again, there are numerous ways to look at “brightness” and I’ve chosen just one here – which is admittedly a little short-sighted.
Colorful and bright
Finally, I would like to try to merge lightness and colorimetry. To do this, I use color volume: it characterizes a TV’s ability to display content with a wide range of colors at different brightness levels. This is important for HDR displays and content, for example. Here is the corresponding data set, broken down again by display type.
Color volume (measured as percentage coverage 1,000 cd/m2 -Coverage DCI-P3 in the ICTCP color space). QD-OLED data points are the red triangles.
The minimum color volume has increased every year – even the cheap LCD TVs are getting better and better.
The spread of the QLED data will be significantly larger in 2019 (at the lower end). Possibly this is when quantum dots made their way into the lower cost LCD TVs and some design decisions were made that resulted in lower color gamut/brightness/color volume. The “worst” QLEDs continued to improve over the following years.
“QD OLEDs lead with a great combination of color and brightness.”
2021 saw a huge jump in maximum color volume across all television types, with color volume increasing from a maximum of 55-65 percent in previous years to over 90 percent in 2021 and 2022. I wonder if mini LEDs were the driving force here. But OLEDs also saw a significant increase (maybe deuterium again?).
This article is first appearing at Display Daily
(uk)
