Determining the error in measuring the spherical concave mirror radius of curvature with a laser rangefinder

Abstract

An instrument and technique for assessing errors of measuring optical surface radius of curvature with a laser rangefinder are presented. Errors of optical instrument alignment with a wave-front sensor are shown to influence the accuracy of measuring the mirror radius. Errors of the rangefinder-aided technique for measuring the surface radius are estimated. A computer analysis shows that the developed scheme of misalignment measurement allows a relative error of 0.02 – 0.3 % to be attained for mirrors ranging in radius from 1 m to 10 m. The choice of the accuracy characteristics of the rangefinders used for measuring the optical surface radius of curvature is justified.

Keywords

• measurement error
• spherical mirror
• schack-hartmann sensor
• wavefront sensor
• radius of curvature
• laser rangefinder
• range measurement
• misalignment calculation