Military/avionics: Design decisions for a head-up display: This F-14 fighter optics retrofit case history is a prime example of analyzing and selecting design options

In modern high-speed aircraft it is vital that primary flight control information be clearly and unobstrusively presented to the pilot. The head-up display (HUD) meets this requirement by providing relevant scales, alphanumerics, symbology, gunsight reticle, etc., superimposed on the pilot's forward field of view. With most HUD designs, the information is calligraphically presented on a high-brightness cathode-ray tube and projected through a collimating lens to a combiner (partially silvered glass) located between the pilot and the aircraft's windshield.