Tolerance analysis is a critical part of the optical design process because it helps predict system real performance, after manufacturing and assembly. To obtain reliable predictions, it is mandatory to use realistic optomechanical models. INO developed Comet software, a powerful standalone application for realistic optical tolerancing analysis. A previous paper demonstrates how a better modeling helps avoid the production of overly expensive optical systems with excellent performances, or on the other hand, the production of inexpensive optical systems with unexpectedly erratic performances. This article presents the methodology used to find the best centering method for an infrared dual-band objective. INO’s Comet standalone software application is used to perform the optomechanical tolerance analysis and computes the perturbations to be applied in the optical tolerance analysis. It will be demonstrated how Comet is quick and easy to use for comparing several centering concepts, helping to find the best trade-off between optical performances and ease of manufacturing. The studied infrared dual-band lens requires almost diffraction limited performances to fulfill the needs of the foreseen application. Therefore, two accurate centering techniques are considered: the active alignment and the QuickCTR autocentering technique. The active alignment is the most accurate method for centering optical elements, but requires expensive instrumentation, human manipulation, and cure time for the adhesive. The QuickCTR auto-centering techniques are almost as accurate as the active alignment but requires a fraction of the effort for centering, thus is less expensive to implement. The presented methodology will show how to get the best compromise by using both techniques.
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