DESIGN OF ATHERMALIZED INFRARED LENSES INVOLVING DIFFRACTIVE OPTICAL ELEMENTS

Abstract

The paper considers the problem of infrared athermalized lenses design involving a restricted list of materials. We analyzed thermo-optical properties of the materials, working in long-wave infrared range, and analysis results are presented. Thermo-opticalproperties of diffractive optical elements (DOE) are analyzed. It is established that the usage of diffractive elements can become a possible solution for the problem of infrared lens athermalization under conditions of restricted list of materials. The set of equations is developed for dimensional calculation of infrared lenses with passive athermalization by DOE application. We studied the effect of a secondary spectrum on modulation transfer function of an optical system in combinations of optical materials with DOE. Research results are given. The example of infrared athermalized lens calculation with DOE is shown.

Keywords

• DOE
• infrared lenses
• secondary spectrum
• thermo-optical aberrations
• athermalization