Method and device for measuring laser wavelength based on bound wavelength

Abstract

The invention discloses a method and a device for measuring laser wavelength based on bound wavelength, and the method has the following steps: adopting a laser with higher wavelength stability as a reference laser, modulating beam of the reference laser and beam of a laser to be measured into orthogonal linear polarized light, and entering in the same Michelson interferometer to form respective interference signals, wherein the measuring arm of the Michelson interferometer moves, the phase relations of the interference signals of the reference light and light to be measured change; and when the phase difference of the two paths of interference signals is 2pi, half displacement of the bound wavelength formed by the reference light and the light to be measured is moved corresponding to the measuring arm. The bound wavelength value can be measured by detecting the zero crossing point positions of the two paths of interference signals twice, and the wavelength value of the laser to be measured can be obtained according to the relationship between the laser wavelength to be measured, the reference laser wavelength and the bound wavelength. The invention has strong environment interference resistance, low cost and easy practicability, and the wavelength measurement precision can be above 10-8.

Description

technical field [0001] The invention relates to a laser wavelength measurement method and device, in particular to a laser wavelength measurement method and device based on synthetic wavelengths. Background technique [0002] In the field of laser technology research and application, the accurate value of laser wavelength is a very important parameter. In the field of geometric measurement technology, a large number of lasers are used as coherent light sources to measure geometric quantities such as displacement, speed, angle, flatness, and straightness. Therefore, accurate detection of the wavelength of lasers is the key to ensuring the accuracy of these geometric quantities and the traceability of their values. . In the field of spectroscopy, in order to tune the tunable laser to the required wavelength, a precise and fast laser wavelength measurement device is also necessary. In addition, in the field of optical frequency standard research, the measurement of the wavele...

AI Technical Summary

Problems solved by technology

The Michelson wavelength meter calculates the wavelength of the light to be measured by calculating the ratio of the number of interference fringes between the reference light and the light to be measured, that is, N R / N U =λ U / λ R (where N R is the number of interference fringes of the reference laser, N U is the number of interference fringes of the laser to be measured, λ U is the wavelength of the laser to be measured, λ R as the wavelength of the reference laser), this method can reach 10 -7 ~10 -8 The measurement accuracy, but in order to improve the measurement accuracy, it is necessary to increase the count value of the interference fringe or use the fringe subdivision method to measure the fractional part of the fringe, which will make the measurement system complex and costly

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