Helmet-mounted display

A helmet-mounted display (HMD) is a headworn device that uses displays and optics to project imagery and/or symbology to the eyes. It provides visual information to the user where head protection is required—-most notably in military aircraft. The display-optics assembly can be attached to a helmet or integrated into the design of the helmet. An HMD provides the pilot with situation awareness, an enhanced image of the scene, and in military applications cue weapons systems, to the direction their head is pointing. Applications which allow cuing of weapon systems are referred to as helmet-mounted sight and display (HMSD) or helmet-mounted sights (HMS). Aviation HMD designs serve these purposes: using the head angle as a pointer to direct air-to-air and air-to-ground weapons seekers or other sensors (e.g., radar, FLIR) to a target by the pilot merely turning the helmet towards the target and operating a switch via HOTAS. In close combat, without HMDs, pilots have to align the aircraft to shoot at a target. HMDs allow pilots to simply point their heads at a target, designate a weapon and shoot. displaying targeting and aircraft performance information (such as airspeed, altitude, target range, weapon seeker status, "g", etc.) to the pilot while "heads-up", eliminating the need to look inside the cockpit. displaying sensor video for the purpose of: verification that the chosen sensor has been cued to the right target or location without requiring the pilot to look inside the cockpit viewing outside terrain using sensor video in degraded visual conditions. HMD systems, combined with High Off-Boresight (HOBS) weapons, allow aircrew to attack and destroy nearly any target seen by the pilot. These systems allow targets to be designated with minimal aircraft maneuvering, minimizing the time spent in the threat environment, and allowing greater lethality, survivability, and pilot situational awareness. In 1962, Hughes Aircraft Company revealed the Electrocular, a compact CRT, head-mounted monocular display that reflected a TV signal onto a transparent eyepiece.