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A prototype thin film electroluminescent (TFEL) display unit (DU) for a control display unit (CDU) design and development was initiated in FY90. Features of the display include high brightness and contrast, sunlight readability, night vision goggle compatibility, light weight, low power, automatic brightness control based on ambient light conditions, modular design, ease of assembly and test, and high reliability. The display contains an integral switch and lightplate that is night vision goggle compatible. The unit was designed for cockpit CDU applications, but can be easily converted for other display needs. The scope of this task was to design and build an ANVIS-compatible, sunlight-readable TFEL CDU DU engineering evaluation unit to replace an existing cathode ray tube (CRT) DU in the V-22 CDU. In order to accomplish that task it was necessary to learn interface, drive, and improved packaging techniques. The electronics were very straight forward using large scale integration (LSI) components. The CDU is mounted in the instrument panel in standard cockpit avionics mounting rails, utilizing quarter turn captive fasteners. The CDU is cooled by natural convection. The TFEL display unit weighs 4.3 pounds compared to 7.8 pounds for the CRT version. Surface mount was a requirement for the drive card due to size constraints. Elastomeric connectors were used to interface the driver board to the glass. The approach uses as much proven design as possible, but makes use of state-of-the-art display technology to provide a low power display unit with outstanding characteristics. The TFEL CDU DU tasks completed during 1991-92 included design and development of: (1) controller and RS-170 digitizer board, (2) high voltage-switching or pre-driver board, (3) row and column driver circuitry for gray scale (double-sided surface mount using sample Supertex HV38 gray-shade column drivers and TI high-voltage row drivers); (4) high and low voltage power supplies; and bezel and packaging. Performance of the TFEL DU, functions and operation of the TFEL CDU DU and key board unit (KBU), and aircraft interfaces are described.
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