条纹周期动态可调的通用型干涉仪

Universal interferometer based on dynamically-adjusted fringe periods

提出一种新型结构的通用型干涉仪,用于实现不同结构、不同形状的光学透镜、光学晶体等元件的快速目视观察与精确测量。该干涉仪利用可相对旋转的双光楔对条纹周期进行动态调制完成实时检测。以两块雅敏干涉平板为主体结构,在双光路中各自放入一对楔角完全相同的光楔对,建立条纹周期和条纹倾斜方向与光楔对相对旋转角度之间的关系,并采用光学晶体畴反转实时检测验证干涉仪的测量性能。试验结果表明,干涉仪的相位检测精度约为0.2rad(λ/30),条纹周期(一对黑白条纹)为0.105～5.993mm/pair,光路中光楔对的相对转角可在0～179°调节。干涉仪具有完全对称的光路结构,由于较高的稳定性和抗干扰能力,可针对不同类型光学元件的结构特点进行条纹周期的实时调制,并可达到较高的检测精度。

A universal interferometer is proposed to realize the eyeballed evaluation and accurate measurement of many kinds of optical elements with different structures and shapes, such as lenses and crystals. In the interferometer, a pair of optical wedges are used to adjust the fringe periods dynamically to implement the measurement in real time. The interferometer takes two Jamin glass plates as a main structure, between which two pairs of optical wedges are laid. All wedges are completely identical in sizes and can be revolved along the axis. The relationship between the relative angle of two wedges and the fringe period is established, and then a real time testing experiment of domain reverse in an optical crystal is introduced to test the performance of the interferometer. The experimental result shows that the measurement accuracy is about 0.2 rad in phase （λ/30）, and the adjustment range of fringe period （white ＆ black fringe） is from 0.105 to 5.993 mm/pair. In the interferometer, the relative angle between the two wedges along the same optical axis can be adjusted from 0° to 179°. The interferometer is charaterized by the symmetrical optical structure, so that it has high stability and can endure strong noise and vibration. It can modulate the fringe period in real time to meet requirements of various optical structures and can reach high measurement accuracy.