I heard that Apple Watch is also equipped with a light sensor. I've always wondered where Apple put the light sensor. Later, I saw the following information on the Internet:
In the news that the US Trademark Office announced the patent of Apple's new optical sensor last year, some netizens thought that this design was simply "morbid". I didn't expect Apple to really apply this "pathological" thing to watches-solar cell ambient light sensors for electronic equipment.
We look to the back of the watch screen, where the touch layer and display layer are covered with some components.
At the bottom of the double-layer cable is a solar cell ambient light sensor for electronic equipment, which is located behind the P- organic light-emitting diode screen. It is precisely because of the ultra-thin P- OLED screen that the sensor can feel the external light. It is known from the name that it is made of solar cell material, and its working principle is to sense the intensity of external light by detecting the current intensity generated by the external light of the fuselage irradiating the solar cell, so as to adjust the screen brightness.
The light sensor is designed at the bottom of the screen, which can be regarded as Apple's first design. It saves the problem of reserving optical sensors on the surface of the watch, thus saving valuable display space on the surface of the watch and improving the screen ratio. From this point of view, Apple Watch is still much more advanced in technology.