Three-dimensional coordinate measuring system and measuring method for object surface

Abstract

The invention, which belongs to the field of laser ranging, discloses a three-dimensional coordinate measuring system and measuring method for an object surface. The system comprises a laser ranging device, a two-dimensional displacement platform and a processor. The laser ranging device includes a light source, an optical isolator, an F-P filter, a spectrograph, a first coupler, a second coupler,a first reference arm, a second reference arm, and a measuring arm. A fixed optical path difference is formed between the first and second reference arms. The optical isolator is arranged a light emitting direction of the light source. The spectrograph is connected with the processor. The processor is used for analyzing and processing interference signals between laser returned by the measuring arm, the first reference arm, and the second reference arm to obtain the depth of a to-be-measured object in a Z axis direction. Besides, a three-dimensional coordinate of the to-be-measured object isgenerated by combining coordinates, reflected by the two-dimensional displacement platform, of the to-be-measured object on X and Y planes. In addition, the invention also provides a three-dimensionalcoordinate measuring method for an object surface. The method and device are simple and the cost is low; a dead zone problem is solved; and high-precision and large-breadth measurement is realized.

Description

technical field [0001] The invention belongs to the technical field of laser distance measurement, and more specifically relates to a three-dimensional coordinate measurement system and a measurement method of an object surface. Background technique [0002] At present, optical three-dimensional coordinate measurement technology has made great progress, and can be classified into two categories: active vision method and passive vision method, and each of them can be subdivided into many specific subcategories. [0003] Three important metrics can be used to evaluate a 3D coordinate measurement scheme: measurement accuracy, measurement range, and reconstruction speed. Among them, the laser TOF ranging technology has a fast measurement speed and a large range, but the accuracy can only reach the level of a few centimeters [1,2] ; The structured light method has a large measurement range, and the accuracy can reach submillimeter level, but it is greatly affected by ambient lig...

AI Technical Summary

Problems solved by technology

Therefore, when the moving range of the object may exceed twice the unambiguous distance, it is impossible to determine whether the object is approaching or moving away from the origin by the moving direction of the signal peak.

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