Variable Aperture Cold Stop
Sponsor / Contract: US Army
Project Term: January 2003 – December 2004
Current IR camera systems employ fixed sized apertures
typically matched to a given f/# lens. For
best performance, apertures must be manually swapped to accommodate changes in
optics f/#. No provisions are
currently available for changing aperture sizes to accommodate changes in scene
brightness in IR cameras.
Develop a variable aperture cold stop compatible with existing IR camera systems.
Substantial increase in IR camera performance when
using multiple f/# optical systems and under conditions of dynamic brightness.
Completed Phase I Continuously Variable Aperture Cold Stop in pour-fill dewar with a manual manipulator.
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