An unequal-arm Twyman-Green IR interferometer for monitoring the shape and quality of the surfaces of large optical items at the grinding stage

Абдулкадыров М.А., Барышников Н.В., Денисов Д.Г., Животовский И.В., Карасик В.Е., Семенов А.П., Шаров Ю.А. Неравноплечий ИК-интерферометр Тваймана-Грина для контроля формы и качества поверхностей крупногабаритных оптических деталей на стадии шлифования // Оптический журнал. 2010. Т. 77. № 10. С. 40–47.

Abdulkadyrov M.A., Baryshnikov N.V., Denisov D.G., Zhivotovskiy I.V., Karasik V.E., Semenov A.P., Sharov Yu.A. An unequal-arm Twyman-Green IR interferometer for monitoring the shape and quality of the surfaces of large optical items at the grinding stage [in Russian] // Opticheskii Zhurnal. 2010. V. 77. № 10. P. 40–47.

M. A. Abdulkadyrov, A. P. Semenov, Yu. A. Sharov, N. V. Baryshnikov, D. G. Denisov, I. V. Zhivotovskiĭ, and V. E. Karasik, "An unequal-arm Twyman-Green IR interferometer for monitoring the shape and quality of the surfaces of large optical items at the grinding stage," Journal of Optical Technology. 77(10), 621-627 (2010). https://doi.org/10.1364/JOT.77.000621

An unequal-arm Twyman-Green interferometer with a working wavelength of 10.6μm has been developed that makes it possible, besides monitoring the shape, to measure the parameters of the microrelief of ground optical surfaces being monitored from the image contrast of the recorded interference patterns. An analytical expression is obtained that connects the contrast with the main characteristic of the asperities--the rms deviation of the heights of the microprofile of rough surfaces. The paper presents the result of the shape-measurement error of the optical surface, monitored while it is being shaped, using the data of a topographic map based on the recorded image of the interference pattern. The main technical characteristics of the interferometric monitoring system are presented.