Abstract

A head-up display ('HUD') projects collimated flight information "head up" to the pilot, being superimposed upon the outside world scene by means of a partially reflective 'combiner' glass. The lens design form is invariably a field-flattened Petzval type, working at an aperture ratio between F/0.9 and F/1.4. Fields of view are typically 25 degrees (total), with an instantaneous field of view ('IFOV') around 16° azimuth by 10° elevation. The IFOV is limited by the finite size of the optics.

© 1990 Optical Society of America