Method for the manufacture of a three-mirror optical system and the optical system resulting therefrom

摘要

The fabrication of an off axis three-mirror telescope on only two substrates allowing two of mirrors to be formed on a common substrate, such as by means of diamond turning. The common substrate configuration is made possible by utilizing a common vertex for both the primary and tertiary mirrors so that alignment subsequent to fabrication requires placement of only two elements. In addition, all three mirrors in this invention share a common optical axis enabling an extremely simple mounting and housing design. The present invention is applicable for use in electro-optical imaging sensors operating from visible wavelengths to long infrared wavelengths. A telescope is formed by the assembly of three off-axis mirrors, including a primary mirror, a secondary mirror and a tertiary mirror. All three mirrors share a common system optical axis. In addition, the primary and tertiary mirrors also share a common vertex enabling the fabrication of two mirror surfaces on a common substrate with a diamond turning process, thus eliminating the need to align the primary and tertiary mirrors subsequent to fabrication. Consequently, system alignment consists of the placement of only two elements, namely the first element, the common substrate on which the primary and tertiary mirrors are formed and the second element which is the secondary mirror.