L14G1 is an NPN photo-transistor. It acts as a photo-detector in the sense that it can convert the incident light into electric response. They are commonly used as sensors usually paired with a light source like LED.
L14G3 is an NPN photo-transistor. It acts as a photo-detector in the sense that it can convert the incident light into electric response. They are commonly used as sensors usually paired with a light source like LED.
