Light detection system, light detection method, and lidar system

Abstract

The invention provides an optical detection system, an optical detection method and a laser radar system, which can be applied to the fields of optical communication, laser radars, laser radar positioning, laser radar ranging, image processing and the like. The system comprises a beam splitting surface, a first light beam reflecting surface, a second light beam reflecting surface, two detector arrays and a reading circuit. The first light beam reflecting surface and the second light beam reflecting surface are respectively used for reflecting two paths of mixed light beams formed by combining the echo light and the local oscillation light through the beam splitting surface; the two detector arrays are respectively used for converting the two paths of mixed light beams into electric signals; the reading circuit is used for processing electric signals output by the two detector arrays, and the distance between the detector arrays, the distance between the light beam reflecting surfaces and the beam splitting surfaces and the distance between the parallel light beam reflecting surfaces are related. Detection is realized by using two paths of coherent signals without completely depending on the magnitude of light echo energy, so that the detection sensitivity of echo light signals can be improved, and the detection distance is increased.

Description

technical field [0001] The present application relates to the field of optics, in particular to a light detection system, a light detection method and a laser radar system. Background technique [0002] As an active sensor, lidar is an indispensable key part in the fields of autonomous driving, robotics, and drones. Lidar is generally composed of a laser, a transmitting optical module, a receiving optical module, a detector and a signal processing module. The laser emits a light pulse with a fixed period, and after being reflected by the target object and received by the detector, the flight time of the light pulse is calculated to calculate the distance of the target object. [0003] In the prior art, the detector array performs direct intensity detection on the received optical signal and outputs an electrical signal. An obvious shortcoming of direct intensity detection is its low detection sensitivity, especially in the application of Flash lidar, since the laser beam i...

AI Technical Summary

Problems solved by technology

An obvious shortcoming of direct intensity detection is its low detection sensitivity, especially in the application of Flash lidar, since the laser beam is a divergent surface beam that irradiates the target object, the light echo energy received by each pixel in the detector array It will be very low. If direct intensity detection is used, the ranging range of the Flash lidar will be very limited.

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