|Category:||Head-Mounted Equipment [HMD/NVG/Glasses]|
|Object Type:||Display Unit|
|Object Name:||Helmet Mounted Sight|
|Year of Manufacture:|
|Location:||Archive Object Store|
The Helmet Mounted Sight allows information to be over-laid onto the pilot's line of sight wherever he may be looking. In this design a collimated image of an LED matrix display is projected off the inner surface of the visor into the pilot's right eye.
The LED Matrix is a 32x32 element transmitting at 640nm (red). The optics uses a single prism and provides focussing and collimation. The optics projects onto a dichroic patch deposited on the inside of the polycarbonate visor. A dark, 15% transmission visor is also fitted to the Helmet. Other key features are a 10° field of view, 16mm exit pupil, Autobrilliance and a 500Hz refresh of the display. The accuracy of the display system is 2mR at the centre and 4mR at the edge.
The Helmet Mounted system is built onto a standard Alpha Helmet and will withstand ejection blast. A Head position system is also used to identify the angle at which the pilots head is pointing such that the appropriate symbology for overlay on the outside world can be presented.
This HMD has a small mains power supply on the end of the umbilical cable which allows it to be used for demonstrations and it has been to many exhibitions and schools.