What is a LDR sensor?
What are Photoresistors? Photoresistors, also known as light dependent resistors (LDR), are light sensitive devices most often used to indicate the presence or absence of light, or to measure the light intensity. LDRs have a sensitivity that varies with the wavelength of the light applied and are nonlinear devices.
What is LDR sensor Wikipedia?
The symbol for a photoresistor. A photoresistor (also known as a light-dependent resistor, LDR, or photo-conductive cell) is a passive component that decreases resistance with respect to receiving luminosity (light) on the component’s sensitive surface.
Who invented LDR sensor?
Hence these Photoresistors are also known as photoconductive cells or just photocell. The idea of Photoresistor developed when photoconductivity in Selenium was discovered by Willoughby Smith in 1873.
How does LDR sensor work?
Working Principle of LDR. This resistor works on the principle of photo conductivity. It is nothing but, when the light falls on its surface, then the material conductivity reduces and also the electrons in the valence band of the device are excited to the conduction band.
What is LDR principle?
The working principle of an LDR is photoconductivity, which is nothing but an optical phenomenon. When the light is absorbed by the material then the conductivity of the material enhances. When the light falls on the LDR, then the electrons in the valence band of the material are eager to the conduction band.
How many pins does LDR sensor have?
Explanation: The LDR is a passive sensor, which means it does not require any external voltage supply for it to run. So it only has two terminals which are to be connected in parallel for maximum performance and so that if the LDR becomes defunct, it does not affect the working of the entire circuit.
