Research on the Influence Model of Collimating Lens Aberrations in Autocollimation System Based on the Ray-Tracing Method

An influence model of collimating lens aberrations in an autocollimation system based on the ray-tracing method is established. With the ray-tracing method, this model can accurately compute the direction and position of each light ray passing through the collimating lens in an autocollimation system, thereby obtaining the light-spot position of each light ray on the sensor and determining the systematic error caused by aberrations. Eventually, this model serves to compensate for the measurement error of autocollimators and improve the accuracy. Simulations and experiments demonstrate that the influence quantity of angular measurement value due to aberrations reaches 0.74 arcsec within the range of ±500 arcsec. Also, in a large-aberration situation, the measurement accuracy is promoted to 3.33 arcsec, approximately five times higher than that without compensation.