Problems of head mounted display

Virtual reality systems used in the entertainment industry and for interfacing to CAD and training equipment require the user to be isolated from the real world and surrounded by the virtual world generated by the computer. This is normally achieved using a head-mounted display with a colour TV screen for each eye, collimating optics, sound system, communications and a tracking system providing position and altitude. All this must be enclosed in a rugged casing which fits tightly to a range of different shapes and sizes of heads and measures up to a number of health and safety requirements covering mechanical stresses on head and neck, ease and safety of putting it on and taking it off, being usable by wearers of spectacles and not transferring skin or hair infections from one user to another. The electrical interface between the unit and the computer providing the signals to drive it must also be safe and protected from damage to or from the user