A basis is provided for choosing thermooptical parameters V and W1R as the true criteria of athermal glasses that minimize temperature distortions in space-based objectives. Previously unpublished results are presented from our studies, involving the calculation of the spectral and temperature dependences of V and W1R, and a detailed summary is given of the thermooptical, optical, and operating parameters of Russian and foreign athermal optical glasses. It is shown that the set of Russian athermal glasses makes it possible to actively intervene in the process of controlling thermal-wave aberrations and to develop an optical system for an objective-apochromat that has a high degree of correction of chromatic aberrations and is nonmisalignable in a variable temperature field. The calculated characteristics are given for thermally stable long-focus apochromatic objectives developed by the authors that are more stable against dynamic external actions and have 20-30% higher image quality than apochromats made from nonathermal glasses. This reduces the requirements on their thermal protection and mass.
O. S. Shchavelev and L. N. Arkhipova, "Athermal optical glasses and thermally stable space-based apochromats (from the materials of a report at the International Conference ??Applied Optics?2002")," J. Opt. Technol. 70, 576-585 (2003)