基于莫尔条纹的红外光束准直技术

Collimation Technique for Infrared Beam Based on Moire Fringe

基于球面波照明时光栅的Talbot像及其与光束准直性的关系,提出一种基于莫尔条纹进行红外光束准直调整的方法,通过移动光栅,由红外面阵CCD观察并测量莫尔条纹方向的变化来调整光束准直,实现了红外光束快速便捷准直。结果表明,在光栅移动时,由于移动同一距离,0级、±1级光波的光程变化不同,条纹将呈现周期性的垂轴移动和周期性的对比度明暗变化,但条纹方向不变,条纹移动及对比度变化不影响准直精度。所提方法克服了红外光束不可见的困难,相较于传统的准直方法,实现了更简单更快速更便捷的准直校正。

A method of infrared beam collimation adjustment based on the Moire fringe is proposed based on the Talbot image of the grating and its relationship to beam collimation under spherical wave illumination.When the grating is moving,the change in the Moire fringe direction is observed and measured by an infrared array chargecoupled device(CCD)to adjust the beam collimation.As a result,fast and convenient collimation of the infrared beam is realized.The results show that,when the grating moves,because the distance is the same,the optical path changes of 0-order and±1-order light waves differ.The fringe shows periodic vertical axis movement and periodic contrast change,but the fringe direction remains unchanged.The fringe movement and contrast change do not affect the collimation accuracy.This method overcomes the difficulty of an invisible infrared beam and achieves simpler,faster,and more convenient collimation correction than the traditional collimation method.