Accession Number : ADA320318

Title :   The Improved Fresnel Virtual Image Display System (VIDS).

Descriptive Note : Final rept. Jan 77-Jan 83,

Corporate Author : NAVAL TRAINING EQUIPMENT CENTER ORLANDO FL

Personal Author(s) : Dykes, Wiley V.

PDF Url : ADA320318

Report Date : FEB 1983

Pagination or Media Count : 113

Abstract : The purpose of the Virtual Image Display System (VIDS) was to show that an infinity visual display could be produced for training simulators which utilizes economical and yet effective components. This report actually describes two different Virtual Image Display Systems of the Fresnel type. The first is a three element system which is not achromatized and the second is a five element achromatized system which utilizes a special liquid filled doublet. Both systems have been designed for use with a standard 25: television picture as an input visual. The eye relief (eye clearance) of both systems is 24 inches and both have a field-of-view which is 48 deg H X 36 deg V. The exit pupil size of each is 12 inches wide by 6 inches high. This improved VIDS design which incorporates curved facets and undercut grooves gives several advantages over the original Fresnel design. The most significant advantages are: the expected transmission increases at the edge of the field from 24% to 75% and because the grooves appear more on edge they tend to be less noticeable to the observer. Only the achromatized VIDS was manufactured as part of the task. This VIDS was subjected to complete optical testing but only the test results are discussed in this report. Transmission therefore could be expected to increase to 85 or 90% with anti-reflection coatings. Distortion through the system was less than 4%. The most noticeable being excessive spherical aberration which causes a sight image movement with head motion. The VIDS was subjectively tested by experienced pilots. They compared the VIDS to their present helicopter simulator . In their opinion over 80% considered the VIDS as brighter, gave a better picture and presented a better illusion of depth than the 2B31.

Descriptors :   *IMAGE PROCESSING, *FLIGHT SIMULATORS, *VIRTUAL REALITY, TEST AND EVALUATION, COMPUTER AIDED DESIGN, FLIGHT TRAINING, RESOLUTION, OPTICAL IMAGES, HELICOPTERS, LIGHT TRANSMISSION, COMPUTER GRAPHICS, VISUAL PERCEPTION, PIXELS, FLIGHT SIMULATION, CATHODE RAY TUBE SCREENS, FRESNEL LENSES, CHROMATICITY.

Subject Categories : Electrooptical and Optoelectronic Devices
      Cybernetics
      Military Aircraft Operations

Distribution Statement : APPROVED FOR PUBLIC RELEASE