Wide light beam illumination three-dimensional gating imaging system of airborne laser radar

Abstract

The invention relates to a broad beam illumination 3D gated imaging system of an airborne laser radar and belongs to the image communication field. In the system, flight data are transmitted to a system control mechanism, the mechanism automatically generates working time-sequence data of various parts of the mechanism, and controls the working time sequence as well as hardware and software; a laser transmits a pulse laser beam according to a laser emission command sent by the system control mechanism, a target is illuminated by an homogeneous beam expander, meanwhile, a laser pulse emission time detection mechanism transmits the detected emission time data to the system control mechanism; a large-aperture telescope receives the reflected light from the target to the illumination laser, an ICCD camera performs gated imaging on a light signal received by the large-aperture telescope according to the time sequence and the gated imaging command, and transmits the data to a signal processing mechanism; and the signal processing mechanism processes the imaging information and generates 3D image information of the target. The imaging system has the advantages of rapid imaging speed, broad detection range, high reliability of measurement data and the like.

Description

technical field [0001] The invention belongs to the field of image communication, and relates to a wide-beam illumination three-dimensional gate imaging system of an airborne laser radar. technical background [0002] At present, the use of airborne lidar for three-dimensional imaging measurement at home and abroad mainly adopts the laser beam scanning three-dimensional imaging method. The laser scanning imaging measurement method is a direct system that effectively maps the points on the earth's surface to three-dimensional coordinates. By measuring the time interval between laser emission and reception, the distance from the platform to the earth's surface points can be measured, so that according to the azimuth of the laser beam The three-dimensional coordinate data of the measured point relative to the airborne platform can be obtained from the angle and the measured distance data. By measuring the target by laser beam scanning, the three-dimensional coordinate data set...

AI Technical Summary

Problems solved by technology

However, there are still some problems in this technology. For example, the scanning laser beam must have high pointing accuracy, and the scanning pointing accuracy will be affected by mechanical wear. To obtain high-density elevation points, it is necessary to emit laser with a high laser pulse repetition rate and have Sufficient pulse energy, small divergence angle, narrow pulse width and other characteristics, and data acquisition through long-term laser point cloud scanning, etc.

In addition, optical-mechanical scanning also increases the complexity of the system, making it difficult to miniaturize and modularize the system

All of these pose challenges to laser manufacturing and system integration.

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