USING THE Y,Y-BAR DIAGRAM TO CONTROL STRAY LIGHT NOISE IN IR SYSTEMS

Stray light in an (infrared) optical system is the radiation that is i ncident on the detector, but does not originate from the conjugate obj ect point. Cool stops are usually placed at strategic locations to dec rease the amount of stray light noise incident into the detector plane . Contrary to the present practice, the stray light control is improve d when the telescope and instrument subsystems are analyzed as a singl e optical system. We describe an approach to the stray light managemen t and control that may be performed simultaneously with the first orde r optical system design using the gamma, gamma-bar diagram.