The wavelength range of near-infrared light is between 700 nanometers and 2,500 nanometers, and its longer wavelengths enable it to penetrate human tissues, so it is widely used in the medical field.
1. Visible light and infrared band
The infrared band is a kind of radiation other than visible light in the electromagnetic spectrum, which has a wide range of wavelengths, and different infrared light lines correspond to different wavelengths. Infrared light and visible light are the same kind of electromagnetic wave, belonging to the continuous spectrum, the difference is that the wavelength is different.
2. Near-infrared, mid-infrared and far-infrared
The infrared band can be categorized into three sub-regions, namely near-infrared, mid-infrared and far-infrared, depending on the wavelength. Among them, the near-infrared band has a wavelength between 0.75 μm and 1.4 μm, the mid-infrared band has a wavelength between 1.4 μm and 3 μm, and the far-infrared band encompasses a wavelength range from 3 μm to 1,000 μm.
3. Applications of infrared band
The infrared band has a wide range of applications in many fields, such as communications, medicine, space exploration and so on. Among them, the infrared band is most widely used in night vision, thermal imaging, unmanned aerial vehicles, infrared temperature measurement, solar observation, infrared telescopes and other fields.
4. Infrared Spectroscopy
Infrared spectroscopy is a common analytical technique that can be used to study the structure and composition of matter. The use of infrared spectroscopy can measure the intensity of infrared light absorbed, transmitted or reflected by a sample, and infer the nature of the sample by analyzing the infrared spectrograms at different wavelengths, thus achieving the purpose of analysis and identification.
5. Sensitive detectors
Because the infrared wavelengths are not sensitive to the light in the environment, it is necessary to specialize in sensitive detectors to monitor and detect. There are many kinds of sensitive detectors, such as indium germanium, silicon, semiconductor materials, etc., commonly used in the production of a variety of infrared instruments, such as infrared cameras, night vision devices, infrared thermal imaging cameras.
6. Infrared radiation sources
There are many sources of infrared radiation, commonly found in the sun, stars, the Earth's surface and the atmosphere of the material. In addition, in industrial production, a variety of high-temperature heating equipment will also produce infrared radiation, which can be used for object heating, drying, sintering, welding and so on.
7. Infrared and the human body
Infrared radiation has different degrees of influence on the human body. Low doses of infrared radiation can be used to treat certain diseases, such as muscle pain, joint pain, etc.; however, high doses of infrared radiation may be harmful to the human body. For example, among workers exposed to high temperatures for long periods of time, they may suffer from skin cancer, sun spots and other diseases.
8. Development of infrared technology
With the continuous development of science and technology, infrared technology has also been continuously improved and innovated. In recent years, the new infrared detectors, optical materials, research and application of infrared technology to promote the development of infrared technology, and infrared technology has been gradually towards the direction of high-precision, high-resolution and multi-functionality. In the future, as the cost of infrared technology equipment is gradually reduced, its application areas will be more extensive.