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rangefinder is a radio navigation device that measures the slanted distance between an aircraft and the ground. It consists of an airborne interrogator and a ground transponder. A method of determining the distance between a radio wave and a radio station by measuring the time it takes an aircraft to reach the radio station.
The range finder is a tool for measuring length or distance. It can be combined with angle measuring equipment or modules to measure parameters such as angle and area. Rangefinders come in many forms and are usually a long cylinder consisting of an objective lens, eyepiece, display, and battery. The laser range finder can also emit multiple laser pulses, and use the Doppler effect to judge the distance of the object from the light source.
Laser range finders generally use pulse method and phase method to measure distance. The process of pulse method ranging is as follows: the laser emitted by the range finder is reflected by the measured object and then received by the range finder, and the range finder records the time of the laser. Half of the product of the speed of light and the round-trip time is the distance between the range finder and the measured object. The accuracy of the pulse method is generally about +/- 1 meter. In addition, the measurement blind zone of this rangefinder is generally about 15 meters.
