Infrared rangefinder is a laser rangefinder that uses infrared light for precise ranging. It is widely used in terrain measurement, battlefield measurement, industrial measurement and control and other fields. Its principle is mainly based on the non-diffusion principle of infrared propagation. As a measuring instrument, the infrared range finder has the advantages of fast ranging speed, high measurement accuracy, easy operation, and easy portability. Let's take a look at the principle, application and characteristics of the infrared rangefinder.

1. What is the principle of infrared rangefinder?

Infrared rangefinder is a type of laser rangefinder, but unlike ordinary laser rangefinders, it uses invisible infrared light as the measuring light source for distance measurement, and its principle is essentially the same as that of laser rangefinders. , but with some minor differences:

Infrared rangefinders mainly use the principle of non-diffusion when infrared rays propagate. Because the refractive index of infrared rays when passing through many substances is much lower than that of ordinary light, many ranging tools need to measure precise targets. Infrared rays are used. The main principle of the infrared rangefinder is the time when the infrared rays are reflected from the reflector after they are emitted from the rangefinder, and the distance to the target can be accurately calculated by considering the propagation speed of the infrared rays.

The working process of the infrared rangefinder is: the modulation signal frequency f generated by the main control oscillator (ie the main vibration) is amplified and added to the GaAs light-emitting tube, and the infrared modulated light is emitted by the current modulation, which is emitted from the emission optical system and emitted. To the mirror of the mirror station, after reflection, the return light is received by the receiving optical system, reaches the silicon photodiode, and undergoes photoelectric conversion to obtain a high-frequency ranging signal. In the automatic infrared range finder, a logic instruction circuit is set up for program control.

2. Application of infrared rangefinder

Infrared rangefinders are widely used in terrain measurement, battlefield measurement, ranging from tanks, aircraft, ships and artillery to targets, and can measure the height of clouds, aircraft, missiles and artificial satellites. It is an important technical equipment to improve the accuracy of high tanks, aircraft, ships and artillery. As the price of laser infrared rangefinders continues to drop, the industry has gradually begun to use laser infrared rangefinders, which can be widely used in industrial measurement and control, mines, ports and other fields.

Third, the advantages and disadvantages of infrared rangefinders

1. Advantages of infrared rangefinders

(1) Fast ranging speed: The infrared rangefinder uses invisible infrared light to measure the distance. When working, an infrared LED emits light, and then another infrared receiver tube measures the intensity of the infrared light, which is very fast.

(2) High precision: The infrared rangefinder is a phase-type photoelectric rangefinder, which measures the distance by indirectly measuring the time, and the measurement accuracy is relatively higher.

(3) Easy to operate: the light source of the infrared rangefinder is semiconductorized, the electronic circuit is gradually integrated, the ranging process is automatic, and the use is very convenient.

(4) Portable: Most of the infrared rangefinders used in industry are hand-held, small in size, light in weight, and very easy to carry.

2. Disadvantages of infrared rangefinders

(1) The measuring range is short. Since the GaAs light-emitting diode is used as the light source, the measuring range is limited, and the measuring range is generally 1-5 kilometers.

(2) The light intensity returned by different surfaces is different. The data returned by black is much lower than that of white, so the light intensity and distance are not necessarily completely proportional. Once the material is changed, the corresponding relationship is also changed.