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.

AbstractA methodology has been developed for measuring radius R _v and eccentricity (conic parameter k ) of large concave aspherical mirrors using a wavefront sensor. Analytical expressions that directly relate Zernike coefficients a _4 and a _9 to parameters R _v and k of the mirror are obtained. It is shown that the technique does not require accurate mirror alignment before measurements. A computer analysis showed that the developed scheme enables measurements with errors of δ R _v < 0.1% and δ k < 0.01 for mirrors with radii from 100 to 2000 mm and with errors of δ R _v < 0.01% and δ k < 0.001 for mirrors with radii of more than 5000 mm.

A technique has been developed for measuring the radii of curvature of optical parts. A scheme of the device based on a wavefront sensor is proposed, which is characterized by a minimum measurement error. The theoretical substantiation of the measurement technique is given. A number of methods that make it possible to measure the radii of curvature of optical parts are considered. The reasons for an increase in the measurement error are analyzed. The results of measurements according to the given methodology with an original prototype device are considered.

A methodology has been developed for measuring radius Rv and eccentricity (conic parameter k) of large concave aspherical mirrors using a wavefront sensor. Analytical expressions that directly relate Zernike coefficients a4 and a9 to parameters Rv and k of the mirror are obtained. It is shown that the technique does not require accurate mirror alignment before measurements. A computer analysis showed that the developed scheme enables measurements with errors of δRv < 0.1% and δk < 0.01 for mirrors with radii from 100 to 2000 mm and with errors of δRv < 0.01% and δk < 0.001 for mirrors with radii of more than 5000 mm.

AbstractA technique has been developed for measuring the radii of curvature of optical parts. A scheme of the device based on a wavefront sensor is proposed, which is characterized by a minimum measurement error. The theoretical substantiation of the measurement technique is given. A number of methods that make it possible to measure the radii of curvature of optical parts are considered. The reasons for an increase in the measurement error are analyzed. The results of measurements according to the given methodology with an original prototype device are considered.