Accession Number:

ADA027177

Title:

Variable-Transmittance Visor for Helmet-Mounted Display.

Descriptive Note:

Final rept. Jul 71-Jun 73,

Corporate Author:

ROCKWELL INTERNATIONAL ANAHEIM CALIF ELECTRONICS RESEARCH DIV

Personal Author(s):

• Dobbins,John P.

Report Date:

1976-07-01

Pagination or Media Count:

80.0

Abstract:

Efficient operation of HMDs helmet-mounted displays requires the use of VTVs Variable-transmittance visors to maintain constant visual contrast between projected images and their backgrounds. No VTVs responding controllably or reversibly with rapidity had been developed prior to this program. A high-priority military objective was to encourage the design and development of such VTVs. An unsolicited proposal to the USAF, based on a new concept, suggested the use of a liquid optronic medium in a sandwich-cell visor configuration with automatic control of variable transmittance. Three such units were installed in flight helmets and delivered to the customer as airborne feasibility demonstrators. These accommodated variations in external brightness over a range greater than 801. Automatic regulation was provided from light sensors, behind the visors, connected to closed-loop, electronic controllers using 28-vdc aircraft power. Controllers were packaged as pocket-size units with self-contained batteries for emergency operation. Most effort was directed toward solving critical problems involved in the selection, processing, and fabrication of materials suitable for this application. Among the many mathematical relationships, both optical and optronic, put to practical use in the VTV design were several derived.

Descriptors:

• *HELMET MOUNTED DISPLAYS
• *FLIGHT HELMETS
• *VISORS
• OPTICAL PROPERTIES
• ELECTROOPTICS
• POLYSTYRENE
• ACRYLIC RESINS
• HUMAN FACTORS ENGINEERING
• LIGHT TRANSMISSION
• POLYCARBONATES
• FLUORINATED HYDROCARBONS
• CELLULOSE

Subject Categories:

• Aircraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE