Development of an angular displacement measurement technique through birefringence heterodyne interferometry

Abstract

An angular displacement measurement sensor with high resolution for large range measurement is presented. The design concept of the proposed method is based on the birefringence effect and phase detection of heterodyne interferometry. High system symmetry and simple operation can be easily achieved by employing an innovative sandwich optical design for the angular sensor. To evaluate the feasibility and performance of the proposed method, several experiments were performed. The experimental results demonstrate that our angular displacement measurement sensor can achieve a measurement range greater than 26°. Considering the high-frequency noise, the measurement resolution of the system is approximately 1.2° × 10^-4. Because of the common-path arrangement, our proposed method can provide superior immunity against environmental disturbances.

High Sensitivity and Full-Circle Optical Rotary Sensor for Non-Cooperatively Tracing Wrist Tremor With Nanoradian Resolution

“…Repeatability is defined as the standard deviation of the measured position error between the starting position and the final position [15]. Definitely, a smaller deviation indicates that the rotary sensor has a higher repeatability.…”

“…Normal interferometric methods need two beams or more to decouple the motions in multi-degree-of-freedom for the angle measurement [10,11]. Some other optical methods can also measure the angle variation , including auto-collimatic method [12], total internal reflection method [13], gratingbased interferometer [14], birefringence heterodyne interferometry [15], surface plasmon resonance [16], selfmixing interferometry [17]， and dual-comb interferometry [18]. These methods reach a high resolution, for instance, 0.001arcsecond angular displacement has been measured experimentally [10], but the sensing range of the above interferometric methods is strictly limited within several degrees.…”

A quick-response and high-precision dynamic measurement method with application on small-angle measurement

“…There are several characterization methods to realize precision angle measurement, such as the laser interferometric method [1][2][3], internal reflection method [4,5] and auto-collimation method [6,7]. All these methods can convert the measured angle into the spot displacement on the imaging device.…”

High Sensitivity and Full-circle Optical Rotary Sensor for Non-cooperatively Tracing Wrist Tremor with Nanoradian Resolution

“…Normal interferometric methods need two beams or more to decouple the motions in multi-degree-of-freedom for the angle measurement [10], [11]. Some other optical methods can also measure the angle variation, including auto-collimatic method [12], total internal reflection method [13], grating-based interferometer [14], birefringence heterodyne interferometry [15], surface plasmon resonance [16], self-mixing interferometry [17], and dual-comb interferometry [18]. These methods reach a high resolution, for instance, 0.001arcsecond angular displacement has been measured experimentally [10], but the sensing range of the above interferometric methods is strictly limited within several degrees.…”