Ranging method based on measurement of laser pulse flight time

Abstract

The invention discloses a ranging method based on measurement of the laser pulse flight time. According to the ranging method based on the measurement of the laser pulse flight time, based on the synchronous clock pulse measurement method, a self-adaptive gradient adjustment slope generator and a differential amplification circuit are adopted, not only can the time duration of the part, synchronous with a system clock, in the laser pulse flight time be accurately measured, but also that the time duration of the part, not synchronous with the system clock, in the laser pulse flight time can also be measured extremely accurately, and thus accurate measurement of a target distance is achieved. The time difference ta between the moment when laser is emitted and the nest rising edge of the system clock and the time difference tb between the moment when the laser returns and the next rising edge of the system clock are linearly converted into a voltage V1 and a voltage V2 respectively, a digital value in linear proportion to ta-tb is output after differential amplification and AD conversion, calculation errors caused by data truncation can be effectively avoided, measurement errors caused by factors such as circuit nonlinearity can be effectively reduced through self-adaptive gradient adjustment conducted through the slope generator, and the ranging method is suitable for ranging occasions with the high accuracy requirement.

Description

Technical field: [0001] The invention belongs to the field of laser distance measurement, and in particular relates to a method for realizing high-precision measurement of target distance by accurately measuring the flight time of laser pulses. Background technique: [0002] Due to the characteristics of high instantaneous power and low average power, laser pulses are widely used in laser ranging devices based on time-of-flight measurement. It uses a laser to emit a narrow laser pulse to the target, and obtains the target distance by directly measuring the round-trip flight time Δt of the laser pulse. where C is the speed of light 3×10 8 m / s. [0003] Ranging accuracy is one of the most important evaluation indicators of laser ranging technology, and the ranging accuracy of laser pulse ranging technology based on time-of-flight measurement is mainly limited by the measurement accuracy of time-of-flight. For example, to achieve a ranging accuracy of 0.1m, The overall meas...

AI Technical Summary

Problems solved by technology

However, due to the impact of truncation at the end of the data and nonlinear phenomena of the circuit, there is still room for improvement in the measurement accuracy of the analog interpolation method

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