Infrared light-emitting diode is a kind of diode that can emit infrared rays, usually used in remote control and other occasions. The commonly used infrared light-emitting diodes are similar in appearance to the light-emitting diode LED and emit infrared light.
- 1. What is infrared light emitting diode
- 2. The working principle of infrared light-emitting diodes
3. Infrared LED parameters
1. What is infrared light emitting diode
The shape of infrared light-emitting diode is similar to that of ordinary light-emitting diode LED, which emits infrared light. The tube voltage drop is about 14V, and the working current is generally less than 20mA. In order to adapt to different operating voltages, current-limiting resistors are often connected in the loop.
Infrared emission tubes have three commonly used wavebands, 850nm, 875nm, and 940nm. According to the characteristics of the wavelength, they are used in different types of products.
850nm wavelength is mainly used for infrared monitoring equipment, 875nm wavelength is mainly used for medical equipment, and 940nm wavelength is mainly used for infrared control equipment.
2. The working principle of infrared light-emitting diodes
Infrared diodes are Electronic components that convert electrical signals into infrared light signals (a type of invisible light). When working, the infrared judge diode receives a group of coded electrical signals, converts the fluctuating electrical signals into fluctuating infrared light signals (pulse signals) and transmits them; the infrared receiving diode receives this group of pulse signals and converts them It is a fluctuating electric signal and output, and then decoded and demodulated by other Circuit elements, and then input into the control circuit to realize the control of the electric appliance.
3. Infrared LED parameters
1. Forward working current IF
It refers to the maximum average forward current that the pipe is allowed to pass through for a long time. Because the current passing through the junction consumes a certain amount of work to cause the tube to heat up, if the tube runs over IF for a long time, it will burn out due to overheating. Therefore, the maximum average forward working current of the tube in use must not exceed IF.
2. Optical power P0
Refers to the part of the electrical power input to the light-emitting diode converted into light output power. The greater the optical power, the longer the emission distance.
3. Peak wavelength
It refers to the light-emitting wavelength corresponding to the maximum light intensity among the near-infrared light emitted by Jiangwai LED.When selecting the infrared receiver tube, the peak wavelength of the received light should be as close as possible to the peak wavelength
4. Reverse leakage current IR
It refers to the magnitude of the reverse current when the tube is not reversely broken down, and it is hoped that the smaller the better.
5. Response time Tw
Due to the existence of the PN junction capacitance of the infrared light-emitting diode, its operating frequency is affected. At present, the response time of infrared light-emitting diodes is generally 10-6 to 10-7 seconds, and the highest operating frequency is tens of MHz.