Length measurement precision calibrating method and device for laser tracker

Abstract

A length measurement precision calibrating method and device for a laser tracker belongs to the measurement and calibration field of optical instruments, and are aimed at solving the problems of the prior art that the calibrating precision of an ultra-long high-precision guide rail is low, the machining cost is high, the length measurement range is small and the occupation space is large. An interference length of a double-frequency laser interferometer is taken by the calibrating device as a length basis. Platforms spaced from each other at certain intervals within the measurement range and an adjustable pedestal above the platforms together form a high-precision virtual guide rail. Right-angle prism units are utilized to adjust the space of two measurement light beams, and five prism units are utilized for turning of light paths. In this way, length measurement precision calibration is conducted on a laser tracker within the ultra-long measurement range in a limited space. The calibrating method includes the steps: leveling a light beam of a laser interferometer; adjusting the virtual guide rail to realize flatness and linearity that are needed by calibration; adjusting an emitting light beam of the laser tracker to enable the emitting light beam to be parallel to the light beam of the laser interferometer; forming a measurement optical path; fixing a reflector, and adjusting the two measurement light beams and enabling the two light beams to parallel to each other so that an Abbe error is eliminated; conducting measurement; and performing data processing.

Description

technical field [0001] The invention relates to a method and device for calibrating the length measurement accuracy of a laser tracker, belonging to the field of optical instrument measurement and calibration. Background technique [0002] The laser tracker is a new type of large-scale space three-dimensional coordinate measuring instrument developed in the world in recent years. It can track and measure space points in real time. It has the characteristics of high precision, high efficiency, portability, and simple operation. Primary means of precision measurement. [0003] The basic working principle of the laser tracker: the measurement beam emitted by the laser is divided into two beams by the interference beam splitter, one beam is directly transmitted to the interferometer, and the other beam is sent to the target mirror through the tracking mirror. The light reflected by the target mirror returns parallel to the original beam. After reaching the beam splitter, part o...

AI Technical Summary

Problems solved by technology

[0009] In order to solve the problems of low calibration accuracy, high processing cost, small length measurement range, and large space occupation of ultra-long and high-precision guide rails in the prior art, the present invention provides a length measurement accuracy calibration method and device for a laser tracker

Images