You have attempted to access the full-text of an Early Posting article. Access is available via an institutional subscription.
See the Early Posting FAQ page for additional information.
See the Early Posting FAQ page for additional information.
3DOF Displacement Sensor Based on Self-imaging Effect of Optical Micro-gratings
Applied Optics- received 03/14/2024; accepted 04/21/2024; posted 04/22/2024; Doc. ID 523811
- Abstract: In recent years, there is an increasing demand for multiple degrees of freedom (DOF) measurement system with high performance and high integration. Here, we report a 3DOF displacement sensor based on Self-imaging effect of optical micro-gratings. Optical field distribution behind a micro-grating with a period of 3μm is analyzed theoretically. Transmission properties of a double-grating structure are investigated in theory. In the experiment, 3DOF displacement measurement within a range of 1mm is demonstrated. Using an interpolation circuit with subdividing factor of 1000, displacement measurement with theoretical resolution of 3nm is realized. The experimental resolution is ~8nm. An error within 2μm is obtained experimentally within a range of 1mm for 3DOF measurement. With a few optical components such as beam splitter prism and beam expanders, the sensor shows potential in developing ultra-compact multi-DOF displacement measuring systems. Together with a nanometric resolution, the 3DOF displacement sensor has shown great potential in applications such as high-precision mechanical engineering and semiconductor processing.