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Variable Aperture Cold Stop - VariAp®*

OptoKnowledge can design and provide VariAp® Kits for any IR camera (hermetically sealed Stirling cooled, or repumpable) to replace a fixed cold stop

Key Features




VariAp® Assembly   Cold VariAp® over a cold filter-wheel

VariAp® Assembly


Cold VariAp® over a cold filter-wheel

Through the SBIR program, OptoKnowledge developed a continuously variable aperture cold stop (VariAp®) for use with infrared (IR) cameras. The VariAp® is advantageous because it enables the same IR optical system to be used for both wide field search and long-range automated target recognition without compromising image quality. In addition, automatic brightness control can be used for high dynamic range scene imaging.

This technology is a major advance in tactical Forward Looking Infrared (FLIR) systems and has enabled the Army to define third generation systems as incorporating dual f/number technology. This allows system designers to optimize cooled infrared systems for different field of view applications and to obtain longer identification and recognition ranges in the Narrow Field of View (NFOV) while at the same time optimizing for wide area search applications, airborne sensing, targeting, or other Wide Field of View (WFOV), detection-focused, operations.

Example of Dual Band MW/LWIR Sensor with VariAp®

For Complete Product Information: Call 1.310.756.0520

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