A distance measuring device and a distance measuring method based on a constant threshold value discrimination method

Abstract

The invention discloses a distance measuring device and a distance measuring method based on a constant threshold time discrimination method. In the pulse laser distance measuring device based on the constant threshold discrimination method, an optical attenuation plate is used to adjust the pulse laser output intensity and change the obstacle distance , continuously record the measurement distance and pulse width at different distances and different laser intensities, and then perform primary fitting and secondary fitting on the distance data and pulse width data to obtain the final measurement distance formula after drift error correction, and compensate for the single threshold. The time drift error can reduce the impact of the echo energy change on the pulse laser ranging accuracy based on the constant threshold discrimination method, and there is no need to increase the complexity of the circuit, and the method is simple.

Description

technical field [0001] The invention belongs to the field of laser measurement, and in particular relates to a distance measuring device and a distance measuring method based on a constant threshold value identification method. Background technique [0002] Pulsed laser measurement technology uses laser as the light source and laser as the carrier. According to the principle of flight time, the distance is measured by detecting the time difference between the laser emission pulse and the laser echo. It has the advantages of simple structure, low price, high reliability, and anti-interference. It is widely used in civilian and military fields due to its advantages such as strong compatibility and no need for cooperative targets. [0003] In order to detect the arrival time of the laser echo pulse, a time discrimination circuit is generally used. The purpose of time discrimination is to convert the analog signal of the laser echo into a digital logic signal with time informati...

AI Technical Summary

Problems solved by technology

The actual situation is that 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. Differences exist, causing time drift errors

At the same time, the echo waveform is related to the characteristics of the detected target. Even if it is the same target and the same distance, the angle between the target and the optical path is different, and the intensity of the echo is also different, resulting in the amplitude of the electrical signal after photoelectric conversion. Changes and changes, different amplitudes produce differences in output time after passing through the time discrimination circuit, resulting in time drift errors

Images