Rigid geometric-optics autocollimation model and its theoretical analysis based on ray-tracing method

摘要

A rigid geometric-optics autocollimation model is established using ray-tracing method to overcome the limitations of conventional autocollimation model due to its lack of necessary parameters. The established model describes the transmission process of the light rays that are emitted from the illuminated target plane and transmit through the autocollimation system and return back to the receiving plane. Simulation results of the model indicate that the cross-talk of 2D micro-angle measurement in autocollimation can be 0.035 arcsec in a measurement range of ±1000 arcsec. The coordinate deviation of ±3 mm from the optical axis of the points on the target plane could result to a variation of-0.045 to 0.246 arcsec in autocollimation. The defocus of ±50 urn of the target plane and the receiving plane could result to an error of 0.278 arcsec. The variation of measurement distance from 200 to 2000 mm could result to a maximum error of 0.500 arcsec in autocollimation while the defocus of receiving plane is 50 urn. The established model can be used for further analysis and improvement of autocollimation.