5PCS 3.3V-5V Photodiode Module LM393 Light Sensor Switch Module for Arduino Raspberry Pi Photosensitive Diode Detection Switch. Photodiode module is most sensitive to the ambient light, generally used to detect the brightness of the ambient light intensity, photoresistor sensor module Universal In most cases, the difference between the two is that photodiode module directional, can sense the fixed the direction of the light source.
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