Abstract
We propose a method for small displacement measurement based on the angle deviation to phase change transformation. The phase change of common-path heterodyne interferometry due to the angle deviation of incidence of a light at interfaces caused by the displacement is detected by a lock-in amplifier. To obtain more accurate results we used an angular amplifier to increase the angle deviation and utilized a surface plasmon resonance (SPR) sensor to enhance the performance of phase detection. When a translator moves one of two face-to-face plane mirrors at an end and then rotates it a small angle, a light is incident onto the mirrors and reflected times. The outgoing light is also deflected times of the angle and incident into a SPR sensor. Thus the phase shift due to the angle deviation is amplified times. The accumulated phase shift is proportional to the amplified angle deviation and displacement. Therefore, the phase change is obtained and the displacement is measured. The amount of movement required can be as low as 0.13 μm without an SPR sensor or 0.08 μm with an SPR sensor. The maximum measurement range can reach 1000 μm.
© 2015 Optical Society of America
Full Article | PDF ArticleMore Like This
Ming-Hung Chiu, Chen-Tai Tan, and Ji-Yuan Li
Appl. Opt. 54(13) D1-D7 (2015)
Qianbo Lu, Chen Wang, Jian Bai, Kaiwei Wang, Wenxiu Lian, Shuqi Lou, Xufen Jiao, and Guoguang Yang
Appl. Opt. 54(13) 4188-4196 (2015)
Hung-Lin Hsieh and Ssu-Wen Pan
Opt. Express 23(3) 2451-2465 (2015)