Smiths Industries is a world class supplier of multi-purpose color displays for severe environment fast-jet and rotary wing applications. In this paper we describe the technical issues, design techniques and qualification experience gained through replacing shadow-mask cathode ray tube with active matrix liquid crystal display (AMLCD) devices in our 5 inch and 6 inch display products. The operational needs for primary flight/mission displays are reviewed from which display brightness, dimming range, contrast, viewing angle and resolution requirements are derived. These requirements when combined with the environment conditions found in a jet fighter cockpit challenge the display designer to find novel cost effective solutions. We shall discuss: the development of an AMLCD for severe environment applications; the development of a backlight to achieve long life, wide luminance range and compatibility with night vision imaging systems; mens to manage the local thermal environment of the AMLCD and the backlight. Practical realization of these solutions are demonstrated in our 5 inch and 6 inch multi- purpose color display products which have been qualified for flight in severe military environments. Operator and engineering evaluations have been made in representative lighting environments and through flight trials to compare the performance of AMLCD against our traditional 'de-facto' standard CRT products.
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