Abstract

A window for an endo-atmospheric seeker optical system must maintain its optical quality while being subjected to high heat input from an external flow. We have analyzed the optical effects associated with coolant channels that are internal to the window and that control temperatures within the window material. These channels partially obscure the clear aperture, and temperature gradients between channels cause spatial variations in optical path through the window. In the seeker's image plane the intensity distribution is affected by amplitude and phase aberrations associated with the coolant channels. We have modelled the window temperature distribution for various channel structures, calculated the window infrared thermal emission, and predicted image-plane intensity distributions. Design tradeoffs for optimum performance will be discussed.

© 1992 Optical Society of America