Optical path system and laser radar

Abstract

The invention discloses an optical path system and a laser radar. The optical path system is used for emitting N synchronous light rays into the rotary polyhedral prism; n scanning lights are formed by rotating the polyhedral prism; the scanning light is reflected by the fixed polyhedral prism to form N parts of vertical scanning light synchronously emitted from the circle center to the outer direction; compared with a single light source, the refreshing rate is improved by N times; when the refresh rate of 1 / N is maintained, the scanning duration of each horizontal angle is correspondingly increased; the scanning time in the vertical direction in the horizontal scanning angle is prolonged; improving vertical resolution, laser radar, the device comprises N (at least two) laser transmitters, a optical path system, a horizontal rotating structure and a motor control module, laser emitted by the laser emitter emits N parts of vertical scanning light through the optical path system, the rotating speed can be reduced under the condition that the refresh rate is not changed, the scanning duration of each horizontal angle is increased, and therefore the vertical scanning time in the horizontal scanning angle is prolonged, and the resolution in the vertical direction is improved in a multiple-level mode.

Description

technical field [0001] The invention relates to the detection field, in particular to an optical path system and a laser radar. Background technique [0002] In fields such as autonomous driving, the higher the horizontal resolution, vertical resolution and refresh rate of lidar, the better the safety of autonomous driving. The laser radar in the prior art is mainly divided into two categories, the first category is a rotating multi-line laser radar, and the second category is a non-rotating laser radar, that is, a solid-state laser radar. [0003] The first type uses mechanical rotation to realize 3D scanning, which can meet the technical requirements of unmanned driving for 0.1° horizontal resolution (360°), 0.2-0.3° vertical resolution (up and down 15°) and 10-20 frame refresh rate, but The resolution in the vertical direction is proportional to the number of laser transmitters and receivers. For example, if you want to subdivide 128 parts in a 30° field of view in the v...

AI Technical Summary

Problems solved by technology

However, the second type of solid-state lidar can only scan in one direction and cannot scan 360°. Multiple such solid-state radars must cooperate to achieve the effect of the first type of lidar, and only the first type of technology is relatively mature, so the cost cannot be greatly reduced. drop and mass production

[0005] Invention patent CN107153185A discloses a laser radar and a laser radar control method, which uses a vertical vibrating mirror and a horizontal rotating structure to complete three-dimensional scanning, and uses a transmitter to scan in the vertical direction through the vibrating mirror, replacing multiple transmitters in order to reduce costs and The structure is complex, but since unmanned driving requires a horizontal resolution of 0.1° and a refresh rate of 10 frames or more, and a measurement distance of 200m, according to this technical requirement, the time for scanning 0.1° in the horizontal direction is 27μs. And each measurement time is at least 2μs, and only 13 measurements can be made in the vertical direction, that is, the vertical resolution can only be 2.2°, so it cannot meet the technical parameter requirements of the first multi-emitter / receiver lidar, and cannot Completely replace the first type of lidar mentioned above

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