Dual-band infrared lenses design

Abstract

Problems of designing dual band lenses were considered. The main problem is color correction in two spectral bands simultaneously because of dispersion issues between two bands for all optical materials. Another challenge is designing the lens with a few optical elements as possible. It results in complication of design dual band lenses compared with single-band lenses design. Dual band lenses design methods using two and three optical materials were discussed. All material combinations in MWIR and LWIR bands for most used materials have been investigated. F/number of single components in infrared lenses has limitation because of high f/number of an overall lens. In the agreement with this fact, we have provided a criterion for selection of good combinations. The results of calculations were tabulated. Manufacturability of all material combinations has been analyzed, and the best combination was obtained. Various designs for the best combinations have been produced. Also, image quality and tolerance sensitivity analysis of these designs was made, so we also provided a criterion for selection of good designs for the same material combination.