The photoresistor is a kind of resistor made by the photoelectric effect of semiconductor, whose resistance value changes with the intensity of incident light; the incident light is strong, the resistance decreases, the incident light is weak, and the resistance increases.
The photoresistor are generally used for light measurement, light control, and photoelectric conversion (converting changes in light into changes in electricity). In addition, the photosensitive resistor is a semiconductor photosensitive device, in addition to high sensitivity, fast response, good spectral characteristics and r-value consistency, etc., it can maintain a high degree of stability and reliability in the harsh environment of high temperature and high humidity.

(1) Photocurrent and bright resistance. Under a certain applied voltage, when light is irradiated, the current flowing through the photoresistor is called the photocurrent, and the ratio of the applied voltage to the photocurrent is called the bright resistance, which is usually expressed as "100LX".
(2) Dark current and dark resistance. Under a certain applied voltage, when there is no light, the current flowing through the photoresistor is called dark current. The ratio of the applied voltage to the dark current is called the dark resistance, which is usually expressed as "0LX".
(3) Sensitivity. Sensitivity refers to the relative change value of the resistance value (dark resistance) when the photoresistor is not irradiated with light and the resistance value (bright resistance) when the photoresistor is irradiated with light.
(4) Spectral response. Spectral response, also known as spectral sensitivity, refers to the sensitivity of a photoresistor under different wavelengths of monochromatic light. If the sensitivity at different wavelengths is plotted as a curve, the curve of the spectral response can be obtained.
(5) Light characteristics. The illumination characteristic refers to the characteristic that the electrical signal output by the photoresistor changes with the illuminance. It can be seen from the light characteristic curve of the photoresistor that as the light intensity increases, the resistance of the photoresistor begins to drop rapidly. If the light intensity is further increased, the change in resistance value will decrease, and then gradually become flat. In most cases, this characteristic is non-linear.
(6) Volt-ampere characteristic curve. The volt-ampere characteristic curve is used to describe the relationship between the applied voltage of the photoresistor and the photocurrent. For the photosensitive device, the photocurrent increases with the increase of the applied voltage.
(7) Temperature coefficient. The photoelectric effect of photoresistors is greatly affected by temperature. Some photoresistors have higher photoelectric sensitivity at low temperatures, but lower sensitivity at high temperatures.
(8) Rated power. Rated power refers to the allowable power consumed by the photoresistor in a certain circuit. When the temperature rises, the power consumed decreases.

? Cameras
? solar garden lights
? lawn lights
? currency detectors
? quartz clocks
? music cups
? gift boxes
? mini night lights
? light sound control switches
? street light automatic switches
? various light control toys
? light control lighting
? lamps
? other light automatic switch control field