What is the principle of infrared rangefinder
As a precision measurement tool, infrared range finder has been widely used in various fields. Range finders can be divided into ultrasonic range finders, infrared range finders, and laser range finders. The so-called infrared rangefinder refers to the laser infrared rangefinder, that is, the laser rangefinder. Infrared rangefinder----an instrument that uses modulated infrared light for precise distance measurement, and the measurement range is generally 1-5 kilometers.
Infrared range finder is also called "infrared photoelectric range finder". A phase-type photoelectric rangefinder with infrared light as the light source. Gallium arsenide light-emitting diodes are usually used as the light source, and its light intensity changes with the injected electrical signal, so it has the dual functions of a light source and a modulator. Its measurement range is relatively short, mostly within 5 kilometers. Due to the semiconductorization of the light source of the infrared rangefinder, the gradual integration of electronic circuits, and the automation of the ranging process, the instrument has the advantages of small size, light weight, easy operation, fast ranging speed, and high precision. Widely used in water conservancy, mining, urban planning and military engineering survey.
It works as follows:
It uses the principle of non-diffusion when infrared rays propagate. Because infrared rays have a very small refractive index when passing through other substances, long-distance rangefinders will consider infrared rays, and the propagation of infrared rays takes time. Received, and then the distance can be calculated according to the time from sending out to being received and the propagation speed of infrared rays, so the industry is called laser infrared photoelectric range finder, and its magnet is a special strong magnetic permanent magnet.
The modulated signal frequency f generated by the main control oscillator (namely the main oscillator) is amplified and added to the GaAs light-emitting tube, and the infrared modulated light is emitted through current modulation, and emitted from the emission optical system to the reflector of the mirror station, after reflection , the return light is received by the receiving optical system, reaches the silicon photosensitive diode, and undergoes photoelectric conversion to obtain a high-frequency ranging signal.
In the automatic infrared rangefinder, a logic command circuit is set for program control. The novel range finder developed in recent years has even adopted a microprocessor system, which can not only complete the above-mentioned program control, but also develop other automatic test functions, including various methods of distance measurement, reduction and self-test, etc. , very convenient to use.
