To understand why this analysis is so important for you, player or… future player of the Steam Deck Oled, let’s first explain in understandable terms what PWM or screen flicker means. PWM is a technology (software) used by 95% of the screens in the market to successfully adjust brightness from 100% to 0%. However, what you may not know is that to achieve this, they turn off and on the screen we use at such a fast speed that the eye cannot see it, but it can feel the consequences, and this is the actual flicker.
PWM screens are like a light bulb; you can turn them on at 100% or turn them off completely by pressing a switch. The difference is that PWM regulates brightness by creating an illusion to your eyes, using this flicker at different speeds and frequencies as you lower the brightness (as you may recall, turning on and off the screen at speeds invisible to the eye). To give you an idea, it’s like someone shining a flashlight in your eye instead of a constant light, turning it on and off very quickly… isn’t it annoying?
To assess the PWM of my Steam Deck Oled, I will use two instruments that will provide precise results of different types: the Radex Lupin and the Opple Light master Pro. Both will measure PWM at different brightness levels on the Oled (100%, 75%, 45%, 10% brightness) and also export graphs with the data for better understanding.
Radex Lupin: The device will yield a result by measuring the screen from 0% to 100%, with each percentage meaning the following:
- 5% or less: Indicates the screen is in the green zone and is good for the eyes, with little or no flicker.
- 5%-10%: Flicker may still be acceptable, but we are in a more borderline or yellow zone, still decent.
- 10-20%: Some people may start to feel significant discomfort here; flicker becomes noticeable.
- 20%-100%: In this range, especially the higher the value, the worse it is. It’s a high-risk zone, and the screen is not recommended for the eyes.
Opple Light Pro:
The first image will show a color map, where the green dot indicates the zone of our screen: red for high eye risk, yellow for low risk, and green for no risk.
Which zone we fall into depends on two variables that correlate in the final result.
1. Modulation Percentage (%): A higher percentage is associated with more eye fatigue and headaches, especially at higher brightness levels. Higher values pose a higher risk, and anything above 20% becomes concerning.
2. Frequency: The frequency indicates, in hertz, the speed of flickering—how many cycles of on and off occur per second. Higher frequency values mean that even with high flicker (modulation percentage), it happens so fast that there is less risk of our eyes perceiving it. A low value implies a high risk, and a very high frequency reduces the risk almost to 0%.
The second image will have a graph:
Interpretation of the Nits Graph (Light Intensity) in the Opple Light Flicker Menu:
- Horizontal Axis (Time): Indicates the passage of time during the flicker cycle.
- Vertical Axis (Nits): Represents light intensity in Nits during flickering.
Interpretation:
- Continuous Line: Indicates smoother and less perceptible flicker. (When the line is completely flat, the screen is flicker-free, 100% safe for the eyes).
In this graph, you will practically see how the modulation percentage (without flicker) acts—straight line, with high flicker or PWM (peaks or pronounced graph).
LET’S BEGIN:
BRIGHTNESS AT 100%
Starting with the image above from Radex Lupin, you can see that at 100% brightness, it gives a value of 20.9%. This means that even at the maximum brightness, the Oled’s PWM will be noticeable for many people.
In these next two Opple Light Pro images, the remaining data is provided. In the first image, you can see that in the color map, we are in the red zone of high risk, but very close to the yellow border. This is because the modulation percentage (flicker) is extremely high; 76% is very bad for the eyes, but remember, at very high frequencies, this can be mitigated. Unfortunately, 360% frequency is not enough, although it’s close. So, at a frequency of, for example, 1100%, the flicker would be so fast that most users wouldn’t perceive it.
In the second image, you see the graph. Do you see those drops in the form of peaks?.. those are the moments when the screen turns off in the flicker. Since these peaks are so extreme, they are represented in the high value of 76%. If, for example, these peaks did not exist, and the line was flat and horizontal, the screen would be DC Dimming or flicker-free (free of flickers), 100% safe for the eyes.
BRIGHTNESS AT 75%
Same values and conclusions as at 100% Brightness.
In Opple Light Pro, like with Radex, the values are repeated similarly to those at 100%. The only difference is that the screen brightness has been reduced, as seen in the lux values on the graph, so at 75%, the experience does not improve.
BRIGHTNESS AT 50%
The percentage value from Radex Lupin begins to increase gradually, between 21-25%.
In Opple Light Pro’s images, we again see the reproduction of this small increase. A 5% more modulation percentage, a bit more flicker, and fewer lux on the graph on average since we are halfway through the screen brightness.
BRIGHTNESS AT 45%
Finally, a significant change occurs here. Below 45% brightness, the Samsung screen begins to apply the most aggressive PWM (also present with less intensity from 50 to 100%, as we saw earlier).
[Radex shows us that the aggressiveness of the flicker increased more than double, from 21% to 55%] no less. As you can see, these values are far from the recommended 1-10% for comfortable viewing for most users.
Here’s the most interesting part. As you see, the frequency remains the same as in the previous brightness levels (360hz) and (spoiler) it will in all subsequent lower brightness levels of the oled screen. So the Hz frequency is fixed. However, the novelty at 45% brightness is that the modulation/flicker percentage reaches its maximum value, 99%. You can see how it rises to the top in the color map. As you can deduce, if the screen’s Hz frequency were higher, we could enter the yellow or green zone. Unfortunately, the Samsung panel was programmed by software to operate at fixed 360%.
The cause of this highly increased modulation percentage is seen in the graph of light pulses/time. Notice how in this graph, the situation has completely reversed; now, the screen is thicker at the bottom, meaning “off,” spending more time turning off than turning on since the top part now has more of a funnel shape and is not flat. If you look at previous brightness levels, at the bottom, it had a peak shape, and at the top, it lasted longer.
Result: The flicker is more aggressive because the screen turns off proportionally more time than it stays on during light pulses.
If you’re curious about this issue, you can see in videos from famous YouTubers with the Steam Deck OLED, when they record with cameras in “slow-motion” mode how, when lowering below 45%, suddenly, the inclined black lines become suddenly darker and thicker, surpassing the luminous gaps on the screen. The black areas are no longer lines; now, their thickness is noticeable. This is exactly what you have just seen in this graph.
Visual example of the previous paragraph in the video of the YouTuber NewEsc where he analyzes his Steam Deck OLED, look from minute 1:50 to 2:34: ¡MEJOR de lo que Esperaba! | Steam Deck OLED Review (youtube.com)
BRIGHTNESS AT 30%
I also took a small data point with Radex at 30% brightness for you to see that the highest flicker and aggressive PWM value (60%) occurs when playing at 30% brightness.
BRIGHTNESS AT 10%
At 10% brightness, Radex provides us with a 46% flicker, which is still a slightly lower value than before but still very negative.
At 10%, the modulation percentage remains at 99%. However, in the light pulse/time graph, we see that here the screen’s flicker is the most exaggerated of all. At the top, we have luminance peaks, and at the bottom, basically large bases representing the screen turning off.
CONCLUSIONS FROM MY ANALYSIS:
The Samsung OLED anti-glare panel of the Steam Deck OLED has proven to be very bad for the eyes in gaming sessions, and the damage is particularly pronounced below 45% brightness. Still, the high risk is common at all brightness levels equally. There will be a percentage of people with very low sensitivity to PWM who will not notice negative symptoms in their eyes. However, another large percentage of people, especially the most sensitive, will notice the symptoms.
The associated symptoms could include nausea, rapid eye discomfort or fatigue, a sensation of grit in the eyes, migraines, and general fatigue, blurred vision after playing.
It is important to note that each individual reacts differently, and although the measured values here offer an objective and recommended range for viewing], the response can vary from person to person. If you are especially sensitive, I cannot recommend this screen and this product. Perhaps you try it, and it doesn’t go wrong for you, but [what my data says is that the risk of it not going well is VERY HIGH.
In my brief experience with the Steam Deck OLED, I have found that although it is a great product and a significant improvement over the Steam Deck LCD at the same price ranges, I have been really disappointed with the little attention to quality control that Valve has had with certain things. On the one hand, a high percentage of people receiving consoles with different assembly or factory defects (loose buttons, poorly assembled trackpads, sticking or noisy triggers, interference sound in jack headphones, dead pixels on BOE panels, etc.). Still, that is a separate issue. I want to focus on what Valve CAN change now regarding the PWM of the OLED screen to solve this problem:
- [Patch SteamOS by adding an option to enable DC-Dimming]: DC-Dimming is an alternative software method of regulating screen brightness that eliminates almost 100% of the flicker of screens of this style where I have tried it or has been implemented. For example, my Xiaomi Mi 9 phone with an Amoled screen and other Xiaomi Oled screens were unusable for me with the default PWM, but once DC dimming, also called “anti-flicker” mode, is activated, the phone is completely usable for hours without tiring. Valve is a company known for listening to and supporting its community and consumers by implementing their requests in software with new updates. **[With this measure, Valve could reduce a high percentage of people who end up with eye fatigue and worse health playing their OLED steam decks to basically almost, It is about offering a product that takes care of your customers’ eyes.
2- A second option by Valve could be instead of implementing a DC Dimming mode, that the
screen still uses PWM, but increase its PWM frequency from 360% to 1100%. Look at what
happens when the Hz frequency on the Steam Deck LCD reaches this value, even at its
worst flicker percentage (99%), it manages to enter the yellow or green zone.
Here is the previous PWM analysis I did of the Steam Deck LCD so that you can compare it with the OLED at each brightness level. The LCD panel is almost flicker-free 100%, entering the green zone at all its brightness levels except at 30%, which stays yellow: (44) Analysis of the PWM of the Steam Deck LCD screen and its level of visual fatigue (and the same style of analysis for Steam Deck OLED next week) : SteamDeck (reddit.com)
While in my use of the Steam Deck LCD Anti-Glare for hours, my eyes have never gotten tired; with Steam Deck OLED, I have already experienced eye strain and a feeling of blurry vision after playing or shortly after starting.