What Are the Different Types of IR Illumination?

Infrared light source is a non-illumination electric light source whose main purpose is to generate infrared radiation. Infrared radiation is a certain range of electromagnetic radiation with a wavelength greater than that of red light. The wavelength is 0.78 to 1000 m and is divided into near infrared (code IR-A, wavelength 0.78 to 1.4 m), mid infrared (IR-B, 1.4 to 3 m), Far infrared (IR-C, 3 1000m) 3 bands.

Infrared light source

(1) Light source

Infrared light sources are generally classified into thermal radiation infrared light sources, gas discharge infrared light sources, and laser infrared light sources.

Thermal radiation infrared light source

It can be a black body, a powered silicon carbide rod, or the like. The black body is the ideal infrared source for thermal radiation. Because at the same temperature, the radiant power density of the black body is the largest.

Incandescent light bulbs can convert more than 75% of the input electrical energy into infrared radiation and can be used as infrared light sources. Because the infrared radiation above 5000nm emitted by the incandescent body is absorbed by the glass shell, the incandescent lamp is a near-infrared and mid-infrared light source. In order to make full use of the infrared radiation of incandescent light bulbs, a reflective glass shell can be used, and the infrared radiation is concentrated to the front through the aluminum reflective surface at the rear of the glass shell to further enhance the infrared radiation effect. In addition, a quartz tube-shaped infrared incandescent lamp can also be used as the infrared light source. It uses the halogen-tungsten cycle principle to work. It has a small size, high mechanical strength, easy installation and use, and a service life of more than 5000 hours.

The silicon carbide rod is approximately black body radiation in the wavelength range of 2000 to 20000 nm after being heated by electricity. It is a medium and far infrared light source.

By coating titanium, zirconium, chromium, manganese, iron, nickel, and silicon oxides or carbides of boron and silicon on the surface of a heating object, a far-infrared light source can be made.

Gas discharge infrared light source

Some gas discharge light sources generate infrared radiation during discharge and can be used as infrared light sources. Xenon lamps have a continuous spectrum and generate intense radiation in the near-infrared region. They are often used as solar analog light sources and heat sources for melting special metals or materials; their infrared radiation is easily modulated and can be used for infrared communications.

Laser infrared light source

Some lasers can be used as infrared light sources. The yttrium aluminum garnet or neodymium glass solid-state laser has a radiation wavelength of 1.06 × 10 nm and is a near-infrared light source. The CO2 gas laser has a radiation wavelength of 1.06 × 10nm and is a far-infrared light source. Semiconductor lasers made of different materials can be used as infrared light sources from near infrared to far infrared at different operating temperatures.

At present, the most popular infrared light source is the array matrix infrared light source, which is often used for high-quality

Infrared light source is a special light source, which has the following characteristics:

Provides high-contrast image inspection when the object is difficult to inspect in the visible light range; it is also very effective for raw materials that have chemical reactions with visible light; it is more effective when used with an infrared camera; the reflectivity is at 500nm and At 850nm gold (Au), the increase is about 1.7 times.

Application fields of infrared light source:

Inspection of metal wires; internal inspection of plastic bottles (film)