Variable Aperture Cold-Stop for Multiple f-number Optics

We propose to implement a simple continuously variable iris mechanism for operation at cryogenic temperatures. The iris is designed to function as a variable cold stop on an existing camera system in use by the Army Test and Evaluation Center (ATEC). The proposed device is based on a similar variable cold stops for SADA and pour-fill dewars that is under development by Opto-Knowledge Systems Inc. (OKSI) (this technology currently has patent pending status). OKSI's has the experience and ability to quickly move beyond the Phase I objectives, as defined by the ATEC solicitation, and begin addressing Phase-II goals in a relatively short amount of time. Under Phase-I we will develop and demonstrate a variable cold-stop for use with an existing camera in use by ATEC. During the Phase-I Option we will implement the variable cold stop in the same camera, and support the Army during a field test use of the new system. Under Phase-II we will address issues such as data collection and transfer rates, as well as, fine tune hardware items such as the optical train.