Scanning beam emitting device, laser radar device and laser radar detection method

Abstract

The invention discloses a scanning beam emitting device, a laser radar device and a laser radar detection method, wherein the scanning beam emitting device comprises an input waveguide, a beam splitting waveguide array, a one-dimensional light modulator array and a coupled beam splitting grating array; the beam splitting waveguide array is connected with the input waveguide, and used for uniformlyand equally dividing light in the input waveguide into multiple channels of light; the one-dimensional light modulator array is connected with the beam splitting waveguide array, and used for performing phase modulation on multiple channels of light in the beam splitting waveguide array; the coupled beam splitting grating array is connected with the one-dimensional light modulator array, and usedfor coupling light in the beam splitting waveguide array into a free space and outputting a two-dimensional beam array having uniform strength; and furthermore, under the modulation of the one-dimensional light modulator array, the beam array can perform scanning along the one-dimensional direction. The scanning beam emitting device is simple in control circuit and high in integration degree; andfurthermore, the spatial azimuth resolution of a laser radar is easily increased.

Description

technical field [0001] The disclosure belongs to the technical field of laser radar, and relates to a scanning beam emitting device, a laser radar device and a detection method. Background technique [0002] Time-of-flight lidar is similar to microwave radar. By measuring the time difference between the emitted laser pulse and the received laser pulse reflected by the object, the distance to the target in a specific azimuth is obtained, and the three-dimensional reconstruction of the target area is realized. Due to the high laser frequency and energy concentration, LiDAR has strong anti-electromagnetic interference ability and high accuracy of angle measurement and distance measurement. [0003] In the prior art, mechanical scanning lidar is widely used due to its large scanning range and low light loss, but its scanning speed is slow, its volume and weight are large, and its cost is high. Phased array lidar achieves flexible beam pointing through beam control, small size a...

AI Technical Summary

Problems solved by technology

However, the current optical phased array is still in the development stage, and there are many key technical problems that have not been resolved, which cannot meet the actual engineering needs.

[0004]The current phased array laser radar has the following problems: the optical phased array is limited by the manufacturing process, and when the distance between the radiation elements is greater than half the wavelength, it will cause the grating lobe problem and the The scanning range is limited; the corresponding two-dimensional phased array element control circuit is complex when the laser radar performs two-dimensional scanning, resulting in large volume, complex process, high cost, and low precision, making it impossible to realize large area array applications

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