Infrared emitting diode infrared lamp working principle and characteristics introduction

Infrared diode current is too small, it will affect the performance of its radiated power, but too large operating current will affect its life, and even burn the infrared diode. It is currently popular in the industry to have a built-in heat dissipation system inside the camera, which can extend the stable working time of the camera.

In the television monitoring system project, infrared lamps were rarely used in the past, but due to the increase in the social crime rate today, infrared rays play a more prominent role in night surveillance, not only treasury, oil depot, armory, library and literature library, cultural relics department, prison It is adopted by other important departments, and it is also adopted in general monitoring systems. Infrared cameras have even been used in television monitoring projects in residential areas. This shows that people's requirements for television monitoring system engineering are becoming more standardized and higher. More and more important places are required to be monitored continuously for 24 hours.

Infrared lamps are divided into two types: solid-state semiconductor (infrared emitting diode) infrared lamps and thermal radiation infrared lamps according to their infrared light radiation mechanism. At present, most infrared cameras use LED infrared light-emitting diodes as the main material of infrared cameras .

Infrared lamps using infrared emitting diodes have the following principles and characteristics: the luminous body is composed of a matrix of infrared light-emitting diodes. The infrared emitting diode is made of a material with high infrared radiation efficiency (usually gallium arsenide GaAs), and a forward bias voltage is injected into the PN junction to excite infrared light. The spectral power distribution is the center wavelength of 830-950nm, and the half-peak bandwidth is about 40nm. It is a narrow-band distribution, which is the range that can be felt by ordinary CCD black and white cameras. Its big advantage is that it can be completely free of red bursts (using 940 ~ 950nm wavelength infrared tube) or only weak red bursts (red bursts have visible red light) and long life.

The emission power of the infrared light emitting diode is expressed by the irradiance W / m2. In general, its infrared radiation power is proportional to the forward operating current, but when it is close to the large value of the forward current, the temperature of the device rises due to the heat consumption of the current, which reduces the light emission power. Infrared diode current is too small, it will affect the performance of its radiated power, but too large operating current will affect its life, and even burn the infrared diode. It is currently popular in the industry to have a built-in heat dissipation system inside the camera, which can extend the stable working time of the camera.