Laser ranging device and laser ranging method thereof

Abstract

The invention provides a laser ranging device and a laser ranging method thereof. The device includes: a photoelectric conversion circuit, used to convert the laser signal into a first electrical signal; an amplifying circuit, used to amplify the first electrical signal and output a second electrical signal; a comparison circuit, used to convert the second electrical signal The voltage value during the leading edge period and the voltage value during the trailing edge period are respectively compared with a preset threshold voltage in real time to obtain a leading edge trigger signal and a trailing edge trigger signal; the timing circuit is used to obtain the corresponding first moment and the second Two moments; and a processor with a built-in algorithm, used to obtain the pulse width value of the second electrical signal according to the time difference between the two moments. The present invention obtains the rough value of the measured distance through the frontier time identification technology, and at the same time obtains the pulse width of the echo signal, and the processor uses the relationship between the distance and the pulse width to call the algorithm to compensate, and obtain the high-precision distance measurement value at the same time The reflectivity of the target object is also obtained.

Description

technical field [0001] The invention relates to a laser ranging technology, in particular to a laser ranging method based on the frontier time identification technology. Background technique [0002] In the prior art, the laser range finder obtains distance information mainly by measuring the flight time of laser pulses. For example, a pulsed laser rangefinder uses a laser as a light source and a laser as a carrier. According to the principle of time-of-flight, the distance is measured by detecting the time difference between the laser emission pulse and the laser echo pulse. Specifically, the laser rangefinder includes a laser transmitter and a laser receiver. The laser transmitter emits a pulsed laser into the space. After the pulsed laser signal hits the surface of the target object, its echo signal is captured by the laser receiver. The distance between the target object and the laser rangefinder can be calculated by the time difference between the moment when the laser...

AI Technical Summary

Problems solved by technology

Compared with the constant ratio timing method and the high-pass time method, the time identification circuit has a simple structure, low price, and strong anti-interference performance, but after the emitted laser pulse interacts with the target object, due to the difference in target surface characteristics (such as roughness, inclination etc.), which tend to cause broadening or deformation of the echo pulse

At the same time, the laser echo pulse is easily attenuated and interfered by objects such as dust, smoke, and water vapor in the air during transmission, and the echo waveform will be broadened and distorted to varying degrees, and the surface reflectivity of the target object also makes the front threshold The arrival time changes, resulting in a difference in the output time, which will eventually affect the measurement accuracy of the laser rangefinder

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