OVERVIEW

Displays are the electro-optical complement to detectors. They produce a photonic image to a human viewer based on an electrical input. A display transduces electronic signals into light. This conversion of electricity to light can occur in a phosphor, LEDs, plasma cells, liquid crystals, or electroluminescent cells as well as other devices. When made into a two-dimensional array, or utilizing a flying spot, a display is formed. Display technology goes hand in hand with sensor system development and, more commercially important, television technology. For a discussion of the history of television and rules relating to cameras, the reader is referred to Chap. 18, "Visible and Television Sensors".

Displays are generally characterized as direct-view as opposed to see-through. This distinction is also made via the terms heads-down displays (HDDs) and heads-up displays (HUDs). The direct-view or heads-down classification includes the classic cathode ray tubes (CRTs) and other monitors. Such a display requires the user's vision to be concentrated on it, because it is the one and only source of information. Displays that are made from a material that allows us not only to see the available images but also to look through the display and view the natural surrounding are called heads-up. These semi-transparent displays have found great use in pilotage and military targeting. They hold promise for widespread application in automobile driving, police activity. medical activity, personal digital assistants, cell phones, and a myriad of other applications.

Both display types suffer from limited brightness...