Development of fast camera objective for spectrograph of Mont Megantique telescope

摘要

A fast (F/1 .55) and wide-angle refractive camera objective has been developed to work with a large-size CCD on the focal plane of the spectrograph of Mont Megantique telescope for large spectral coverage from UV to VIS and up to NIR. The novel camera objective has been designed and optimized with three different glass combinations in order to have higher throughputs for large spectral coverage, especially in UV region. The tolerance analysis of the camera objective is given in the paper. The final opto-mechanical design of the objective is discussed with the consideration of the manufacturing tolerance in the optical and mechanical parts, as given in this paper. The used components have been minimized to reduce the light inherent lost. The optical testing results displayed the good optical performance of the camera with the required resolution for the whole FOV, as predicted by the optical simulation and computation. The broadband AR coating, enhanced on UV region, have been used on each surface of the lenses in the optical system.