Unit Light is a light intensity detection sensor. It integrates a photoresistor and a 10K adjustable resistor, capable of detecting light intensity and setting a light intensity threshold. The resistance of the photoresistor decreases as the incident light intensity increases, thus detecting the change in voltage, and obtaining light intensity data through AD conversion. To achieve more accurate light intensity measurements, this Unit also adopts the LM393 dual differential comparator, used to compare the differential voltage between the photoresistor and the varistor.