About photosensitive sensors

1. Introduction to Photosensitive Sensor

The commonly used materials for making photosensors are cadmium sulfide, and there are also materials such as selenium, aluminum sulfide, lead sulfide and bismuth sulfide. Its working principle is based on the internal photoelectric effect. The stronger the light, the lower the resistance. As the light intensity increases, the resistance value decreases rapidly, and the bright resistance value can be as small as less than 1KΩ. Photoresistors are very sensitive to light. When there is no light, they are in a high-resistance state, and the dark resistance can generally reach 1.5MΩ. Because of its non-contact, fast response, and reliable performance, it occupies a very important position in automatic control and non-electrical electronic technology.

2. Sensor parameters