抄録
This paper presents a design study on an optical setup for fabrication of a two-dimensional grating used in encoder systems. By adding major modifications to the conventional one-axis Lloyd's mirror interferometer, a modified two-axis Lloyd's mirror interferometer has been developed. Based on the wave optics, the two-axis interference patterns to be generated by the proposed optical configuration are simulated. To eliminate unwanted distortion of the two-dimensional micro patterns, polarization of the laser beams is controlled by inserting two half wave plates in the optical path. In addition, pattern exposure tests are carried out by using a prototype optical setup.
