LDR

Photoresistor (Light Dependent Resistor)

This cadmium-sulfide (CdS) photoresistor is a highly responsive analog component whose internal resistance decreases significantly in the presence of ambient light. It acts as an excellent, low-cost optical transducer for detecting day/night cycles, beam interruptions, and general ambient light intensity.

• Dark Resistance: Typically >1 MΩ
• Light Resistance: 10kΩ to 20kΩ (at 10 Lux)
• Peak Spectral Response: ~540nm (Visible light)
• Common Use Case: Automatic dusk-to-dawn street lighting, laser tripwires, and solar tracking systems.