Built-in photosensitive resistor (CDS), Brightness according to ambient light, Automatic IR LED can be opened and closed, More delay infrared lamp working life.

内置光敏电阻(CDS)，根据环境光线亮度，可自动控制红外灯开启与关闭，更能延缓红外灯的工作寿命。

youdao

While substituting the regulation-resistor for light intensity adjustment on the spectrophotometer with this device, automatic adjustment of light intensity is realized.

用这种电路替代原721型分光光度计中的光强调节电位器即可实现自动调节光强。

youdao

As it is made entirely out of circuit board, users can solder components directly to it -- such as a light dependent resistor or a microphone to make it respond to sound.

CNN: , for