OPPO just announced that due to some users feedback, the new ColorOS will have fix for a problem that was most notable on OLED screens. Basically PWM dimming (240Hz) would turn on at low brightness which would cause eyestrain after a while. To fix the issue, OPPO’s ColorOS multimedia development team optimized a low-brightness PWM dimming of OLED screens, which is officially referred to as “DC-like dimming”.
According to ColorOS officials, the development team has tried four types of solutions, including a low-brightness backlight smoothing algorithm, PCC image mask, modified PWM frequency, mask dimming + dither, etc. The first three solutions will have a negative impact on the screen perception. For example, screen color cast, uneven illumination, screen flash screen, gray scale deviation degradation and the like.
Because of that, ColorOS selected the “mask dimming + dither” solution, which calls the Snapdragon Display Engine layer mixer function of Qualcomm Snapdragon platform. The mixer generally handles VR binocular image mixing, or handles the overlay of video and application interfaces. In this case, the layer mixer is transparently mixed with other layers through the Dim Layer.
The final result if a reduced brightness of the content on the entire screen, with a similar effect to the DC dimming technology.
It’s been tested that after ColorOS “DC-like dimming” is turned on, it can effectively reduce the fatigue of sensitive people due to low-frequency PWM dimming. In addition, OPPO has encouraged screen suppliers to produce displays with true global DC dimming which can then be quickly integrated with software.
Which models can use ColorOS “DC-like dimming”?
OPPO Reno‘s upcoming phone releasing on April 10th, along with the Find X, R17 series, R15 series and more models.