Why is the brightness of the POCO F7 slightly change when the screen temperature is high?

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If the brightness of the POCO F7 slightly changes when the screen temperature is high, please refer to the following details:
1. To deliver a better and more comfortable use experience, the phone's visual effects have been carefully optimized at the pixel level across various brightness levels;
2. To minimize flickering, especially under low brightness conditions, the phone uses advanced 3840Hz high-frequency PWM dimming technology;
3. As a result of these adjustments, you can observe a slight brightness change when transitioning between high and low brightness, which is a normal and expected phenomenon.