Laser divergence angle measuring device and measuring method based on full-automatic hole alignment method

Abstract

The invention provides a laser divergence angle measuring device based on the full-automatic hole alignment method, which comprises a computing control unit, a stepping motor controller and a laser. A long-focus length, a hole diaphragm array, a reflector and a CCD (charge coupled device) are sequentially arranged in the horizontal advancing direction of a laser beam generated from the laser, wherein the hole diaphragm array is provided with a plurality of light transmitting holes and located on the focus of the long-focus lens, the reflector and the laser beam form the included angle of 45 degrees, an energy meter is arranged on a vertical light path of the light beam after the light beam is reflected by the reflector, a two-dimensional electric control translation platform is connected to the hole diaphragm array, a one-dimensional electric control translation platform is connected to the reflector, and the computing control unit is connected with the stepping motor controller, the CCD and the energy meter respectively. The two-dimensional translation platform is controlled to move by control signals so that the center of each light transmitting hole is coincided with the center of each laser light spot. High precision in alignment is achieved and the laser divergence angle computed by the device is more accurate.

Description

technical field [0001] The invention relates to a measuring device and a measuring method for a laser divergence angle based on a fully automatic trepanning method, belonging to the technical field of optical detection. Background technique [0002] The laser divergence angle is an important parameter to characterize the quality of the laser beam, so its measurement is very necessary and has practical application significance. Laser divergence angle measurement refers to the far-field divergence angle measured under far-field conditions, which is related to the focal length of the lens and the spot radius of the beam at the focal point of the lens, and has nothing to do with the position of the lens from the waist of the laser beam. The existing laser intensity is usually reduced to 1 / e at the center 2 The corresponding small hole diameter D calculates the divergence angle of the laser beam, that is, the divergence angle of the laser beam θ=2tan -1 (D / 2f), f is the focal l...

AI Technical Summary

Problems solved by technology

At present, manual methods are usually used for alignment, but the center of the beam and the center of the small hole cannot be accurately judged by the human eye, resulting in large errors in the measurement results and cannot be accurately measured; in addition, the original trepanning method is used to measure the divergence angle manually. It is achieved by selecting small holes with different diameters, and each small hole needs to be aligned, so the measurement process is cumbersome

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