Data-fused panoramic displays are currently being developed to provide decision support to military pilots in air-to-air combat environments. This paper reports the findings from a series of studies conducted using simulated data-fused explanatory displays. The displays provided explanations, rather than advice, in an endeavor to keep the pilot in the decision loop while improving the accuracy and/or speed of his mission-critical decisions. In addition to the basic display of the threat type, speed and direction (the control condition), three forms of explanatory displays were presented: text only, graphics only, and text and graphics (redundant). These displays provided information regarding the hostile aircraft's missile engagement zones and success envelopes. For effective human-system interaction, an appropriate level of operator trust is required. A critical determinant of trust is the transparency of the system interface, which should allow the operator to assess the system's accuracy. Two experiments were conducted to investigate the issues of trust and transparency of the different display formats used in the decision support system. Participants were asked to identify the highest threat posed by three hostile aircraft in an air combat scenario in the first experiment, and to assess whether explanations generated for a single hostile aircraft were correct or incorrect in the second. The scenarios, which were designed to present real-world decision tasks, were developed through discussions with RAF aircrew. Low trust was found to have a negative impact on decision-making and situational awareness, with subjects in the low trust condition making fewer correct decisions and reporting lower levels of subjective situational awareness than subjects in the high trust condition. Decision-making with low trust was particularly impaired in the test only condition. Poorer memory for hostile aircraft was observed where explanations were provided, compared to the control condition, in which no explanations were provided. The inability of subjects to identify erroneous textural explanations suggested a lack of transparency in the textual explanations. These results are discussed with regard to the implications of the different display formats for decision-making and situational awareness with data- fused cockpit displays.

Data-fused panoramic displays are currently being developed to provide decision support to military pilots in air-to-air combat environments. This paper reports the findings from a series of studies conducted using simulated data-fused explanatory displays. The displays provided explanations, rather than advice, in an endeavour to keep the pilot in the decision 1oop while improving the accuracy and/or speed of his mission-critical decisions. In addition to the basic display of the threat type, speed and direction (the control condition), three forms of explanatory displays were presented: text only, graphics only, and text aidgraphics (redundant). These displays provided information regarding the hostile aircraft's missile engagement zones and success envelopes. For effective human-system interaction, an appropriate level of operator trust is required. A critical determinant of trust is the transparency of the system interface, which should allow the operator to assess the system's accuracy. Two experiments were conducted to investigate the issues of trust and transparency of the different display formats used in the decision support system. Participants were asked to identify the highest threat posed by three hostile aircraft in an air combat scenario in the first experiment, and to assess whether explanations generated for a single hostile aircraft were correct or incorrect in the second. The scenarios, which were designed to present real-world decision tasks, were developed through discussions with RAF aircrew. Low trust was found to have a negative impact on decision-making and situational awareness, with subjects in the low trust condition making fewer correct decisions and reporting lower levels of subjective situational awareness than subjects in the high trust condition. Decision-making with low trust was particularly impaired in the text only condition. Poorer memory for hostile aircraft was observed where explanations were provided, compared to the control condition, in which no explanations were provided. The inability of subjects to identify erroneous textual explanations suggested a lack of transparency in the textual explanations. These results are discussed with regard to the implications of the different display formats for decision-making and situational awareness with data-fused cockpit displays.

A low-cost Operational Development and Evaluation System (ODES) was developed for evaluating and demonstrating Head Up Display (HUD) technology, including projected out the window graphics. This consisted of commercial workstations and PC's, a prototype autopilot control panel and an engineering F-15 HUD unit. Software utilized functional partitioning to provide maximum flexibility for modification, expansion and rehosting of software functions. For human factors evaluation of Enhanced Vision Systems (EVS), a real-time simulation was needed for subjects to respond to. Real-time simulated enhanced vision, such as that using millimeter wave radar, is not possible without supercomputers or oversimplification of the radar simulation. We solved this problem by defining operational scenarios for evaluation, generating the EVS radar simulation off-line, transferring simulation run results to a Silicon Graphics (SG) machine for B-scope to C-scope conversion and contrast enhancement and recording the SG images on an optical disk, a frame at a time. For real-time simulation, an ODES system was modified to control the playback of the optical disk recorder through the HUD raster subsystem in coordination with the aircraft model position as driven by the autopilot. The system was first put to use in a study of EVS raster obscuration issues.

Pilots use their situational awareness displays to determine their position during important phases of their mission. One of the most common tasks they perform with these displays is the designation of targets. It is of utmost importance that pilots can quickly and accurately designate targets. This study investigated the implementation of different cursor control techniques used to designate targets on a map display. A touch control system, a voice control system, and a traditional target designation control (TDC) on the throttle, all modified by the addition of an aiding algorithm, were compared. Also, the effect of targets located in clusters (the same type of symbols close together) was analyzed. Clusters of zero, two, three, and four symbols were used. Results showed that the touch control system provided the fastest performance, regardless of cluster level. The TDC on the throttle was second best, and the voice control system performed the slowest. The TDC, although having significantly faster designation times than the voice system, had significantly more errors than both the touch control system and the voice control system. Therefore, the use of the touch control system is recommended for this task. Also, either the voice control system or the TDC could be used as alternate methods to designate targets when the use of the touch control system is not feasible in the cockpit environment.

This paper discusses the methods and results of a study which investigated image quality issues associated with transferring flight formats of a transport cockpit from a Cathode Ray Tube (CRT) to an Active Matrix Liquid Crystal Display (AMLCD). Eight subject pilots performed a series of flying tasks in two simulator sessions: one with a commercial grade CRT and the other with a commercial grade, prototype LCD. Subjective assessments were obtained via questionnaires that addressed image quality and useability issues. The results showed that the display formats could be implemented on the test LCD hardware with no significant degradation in image quality or usability. Some considerations for optimizing formats for LCD implementations are discussed.

There are a number of semiconductor materials that have been brought to bear on the display market. Several technologies are actively being pursued to fabricate active matrix liquid crystal displays, including Amorphous silicon (a-Si), Polysilicon (p-Si), Single Crystal silicon (x- Si), and Cadmium Selenide (CdSe). A comparison is made between the various technologies to assess their relative suitability for avionics displays.

Field emitter array-based display technology offers CRT-like characteristics in a thin flat-panel display with many potential applications for vehicle-mounted, crew workstation, and helmet-mounted displays, as well as many other military and commercial applications. In addition to thinness, high brightness, wide viewing angle, wide temperature range, and low weight, field emitter array displays also offer potential advantages such as row-at-a-time matrix addressability and the ability to be segmented.

Harris Corporation, Government Aerospace Systems Division, recognized the need for a lower cost alternative to the Active Matrix Liquid Crystal flat-panel display with potentially superior optical performance, lower power dissipation, and less volume at significantly reduced life-cycle cost. This paper compares the performance of Harris' Active Matrix Liquid Crystal Display (AMLCD) with the potential performance of a comparable FED. The FED offers superior sunlight- viewable optical performance compared with the AMLCD. The FED projects a significant reduction in power dissipation that will enhance the reliability of the displays and reduce the cooling loads on the cockpit design. It also promises reduced volume and weight. The simpler FED manufacturing processed, and the elimination of expendable backlight and heaters, will result in reductions in the cost of acquisition and ownership of flat-panel displays.

The use of an autostereoscopic display (a display that produces stereoscopic images that the user can see without wearing special glasses) for cockpit applications is now under investigation at Wright Patterson Air Force Base. DTI reported on this display, built for testing in a simulator, at last year's conference. It is believed, based on testing performed at NASA's Langley Research Center, that collimating this type of display will accrue benefits to the user including a grater useful imaging volume and more accurate stereo perception. DTI has therefore investigated the feasibility of collimating an autostereoscopic display, and has experimentally demonstrated a proof of concept model of such a display. As in the case of conventional displays, a collimated autostereoscopic display utilizes an optical element located one focal length from the surface of the image forming device. The presence of this element must be taken into account when designing the optics used to create the autostereoscopic images. The major design issues associated with collimated 2D displays are also associated with collimated autostereoscopic displays.

With the advancements made in flat panel display technology and the insertion of these displays within military and civil application, there is a need to establish standardization of active matrix liquid crystal displays (AMLCDS) while this process is in it's infancy. Currently, there are no accepted civil or military standards covering AMLCDS. Since the proliferation of this technology has found a place within DOD applications, a best practices document in the form of a standard was created in 1993. This paper covers the changes made in the third evolution of the 'Draft Standard for Color Active Matrix Liquid Crystal Displays (AMLCDS) for US Military Aircraft, Recommended Best Practices'. This document is published by the Air Force through Wright Laboratory as WL-TR-93-1177 in Jun 94. This paper covers the background and future plans for the document as well as four key revisions: Applicability documents review, Display configurations, Testing and Test standards, and Electrical interfaces.

Flat panel displays are fast becoming a significant source of more defense for less money. Military instruments have begun to use color active matrix liquid crystal displays (AMLCDs). This is the beginning of a significant transition from electromechanical, CRT. dichroic LCD, and electroluminescent display designs to the AMLCD designs. We have the opportunity with this new technology to establish common products capable of meeting user requirements for sunlight-readable, color and grayscale capable, high-sharpness high-pixel count, flat panel displays for military applications. The Wright Laboratory is leading the development of recommended best practice, draft guidance standard, and performance specifications for this new generation, the flat panel cockpit display generation, of display modules based on requirements for U.S. military aircraft and ground combat human system interfaces. These requirements are similar in many regards to those in both the civil aviation and automotive industries; accordingly, commonality with these civil applications is incorporated where possible, against the requirements for military combat applications. The performance requirement may be achieved by two approaches: militarization of displays made to low requirements of a large volume civil products manufacturer like Sharp or integration of displays made to high requirements by a niche market commercial vendor, like Optical Imaging Systems, Litton Systems Limited, ImageQuest Inc., and Planar Advanced Inc. teamed with Xerox PARC and Standish Industries. [Note that the niche market companies listed are commercial off-the shelf vendors, albeit for high requirement low volume customers.] Given that the performance specifications can be met for a particular military product by either approach, the choice is based on life cycle cost and a thin analysis based on initial costs alone is not acceptable as it ignores the fact that military product life cycles and procurements are 20-60 years compared to 1.5 years for civil products. Thus far there is no convincing evidence that the large volume commercial product approach for combat systems will meet the combat performance specification or be cheaper from a life cycle cost perspective. National and economic security requirements require some military/avionic-grade AMLCD production domestically (i.e. in the U.S. and/or Canada). Examples of AMLCD demand and performance requirements in U.S. military systems are provided.

The current RAH-66 Comanche Scout/Attack Helicopter in development for the U.S. Army uses an advanced Controls and Displays architecture coupled to an all glass cockpit. Advanced Mission Computers (MCs) drive state of the art crew station displays. This combination provides unmatched targeting capability while reducing the pilot's and copilot's workload.

This paper is an update to the original presented a year ago at SPIE. Much of the original material will be repeated for the new readers, but the intent is to report on the continuing progress. The system is the Lockheed Sanders Advanced Transport Common Cockpit System. The architecture is addressed with some emphasis on the display characteristics in a human factors and specification sense tied directly to the AMLCD design requirements. Practical aspects of the subsystem design and application will be disclosed.

A cockpit revolution is in the making. Many of the much ballyhooed, much promised, but little delivered technologies of the 70's and 80's will finally come of age in the 90's just in time to complement the data explosion coming from sensor and processing advances. Technologies such as helmet systems, large flat panel displays, speech recognition, color graphics, decision aiding and stereopsis, are simultaneously reaching technology maturities that promise big payoffs for the third generation cockpit and beyond. The first generation cockpit used round dials to help the pilot keep the airplane flying right side up. The second generation cockpit used Multifunction Displays and the HUD to interface the pilot with sensors and weapons. What might the third generation cockpit look like? How might it integrate many of these technologies to simplify the pilots life and most of all: what is the payoff? This paper will examine tactical cockpit problems, the technologies needed to solve them and recommend three generations of solutions.

The cockpit design in the new JAS 39 Gripen combat aircraft is based on an electronic computer-controlled display system. This display system, EP 17, has four areas of presentation: one Head-Up Display (HUD) and three Multi-Function Displays (MFD). The HUD is equipped with a diffraction optics combiner which gives the display high visibility within a large filed-of-view, and with minimal visual interference to the outside world. The Multi-Function Displays in the front panel are a Flight Data Display showing flight and system data, a Horizontal Situation Display that superimposes tactical information on a digital map and a Multi-Sensor Display with, primarily, radar information. This system is supported by a Display Processor (DP) comprising computers, graphic generators, sensor information processors and a digital map memory. The DP also includes an integrated video recording system for recording analog and digital sensor video, bus data and voice.

Active Matrix Liquid Crystal Displays (AMLCDs) are being called upon to operate in environments which are increasingly harsh. The displays studied in this paper were originally designed for an environment from -55 to +85 degree(s)C. Open (bubble canopy) cockpits expose the displays to extremely high solar loads in some environments. This paper presents a summary of modeling techniques used to predict maximum AMLCD temperatures under F/A-18E/F aircraft storage conditions. Results from testing of displays and polarizer lamination test samples in these predicted environments are also presented. The development test process resulted in significant improvements and the identification of other issues which need to be resolved before AMLCDs can be guaranteed to be truly durable in these environments.

A pair of flight data recording and playback systems are described for the F-22 and F-15. These systems employ multiplexing techniques to expand the amount of data recorded and inherent benefit therefrom. Variations between the system accommodate the different avionics architecture of each aircraft.

The future military pilot might have to fly some mission segments--notably ingress, attack, and egress-- without any benefit whatsoever of looking out of the cockpit. Threats, together with night, in-weather, low-level flight conditions and lasers, may require high definition displays in 21st century cockpits. Eventually, a large area display suite may become necessary to survival, let alone mission success. Such a system might be a 2000 cm² (300 in²) head \-down color multi-function, multi-window display coupled with a head-mounted system and would have to operate with a clear as well as an opaque canopy. This paper addressed hardware developments needed to create high definition large area cockpit display systems.

The Improved F-16 Display Unit (DU) is the first use of a ruggedized COTS LCD in a high performance fighter application and is the first color LCD to fly in an F-16 aircraft. The Display Unit (DU) is one of two LRUs that make up the Improved Radar Electro-Optical (REO) Display Set. The second LRU is called the Electronics Unit (EU). The Improved REO Display Set flew for the first time in August of 1994 and will continue flight testing through 1995. In addition to the improved R&M features of the design, the new system provides the capability for increased performance and growth through an open systems modular architecture. This will be demonstrated during testing this year in which the improved REO Display Set will be a key component in the Air Force Reserves Integrated Electronic Combat Feasibility Assessment Project for the F-16C aircraft, by providing a consolidated color situation awareness display. The current EC LRUs are not integrated, and each EC element has its own controls and displays which are dispersed throughout the cockpit. This puts a significant burden on the pilot and limits his ability to react to various threats. The Improved REO Display Set distributed processing capabilities and color displays allow the EC horizontal situation awareness formats to be generated and consolidated on one of the REO system color LCDs through bezel switch selection of available displays. This paper presents the latest performance characteristics of the Improved Display Unit, testing results, and the design trade-offs that lead to the use of a ruggedized COTS LCD rather than a custom military LCD. Following flight testing and pilot evaluation, a decision will be made to proceed with production refinement of the ruggedized design or to transition to a custom LCD designed specifically for military use.

The F-15 Air Navigation Multiple Indicator (ANMI) is the vertical situation display in the F-15A/B and C/D aircraft. The Air Force established the ANMI Prototype Development Program as a form, fit and function replacement for the existing Cathode Ray Tube (CRT) display. Oklahoma City Air Logistics Center (OC-ALC) is the lead agency for the development with financial support from the Producibility, Reliability and Maintainability (PRAM) Program Office at Wright-Patterson. SAIC was selected to design the prototype unit. Figure 1 is an exploded view of this prototype. The F-15 ANMI development required SAIC to address many new challenges. Four unique technical challenges were: (1) the development of a high resolution liquid crystal display (LCD), (2) the interface with an analog signal used to drive the existing CRT, (3) the development of a NTSC output, and (4) the sunlight readable, Night Vision Goggle compatible backlight. These technical aspects of the development are detailed in the body of this paper.

Development and testing of an AMLCD-display to replace a dichroic display in a fighter aircraft environment has presented a unique set of technical challenges. This paper addresses design concepts used on the Engine Fuel Display and proposes design guidelines generally applicable for AMLCD projects.

A new Operator display subsystem is being incorporated as part of the next generation United States Navy (USN) helicopter avionics system to be integrated into the Multi-Mission Helicopter (MMH) which will replace both the SH-60B and the SH- 60F in 2001. This subsystem exploits state-of-the-art technology for the display hardware, the display driver hardware, information presentation methodologies, and software architecture. The technologies to be base technologies have evolved during the development period and the solution has been modified to include current elements including high resolution AMLCD color displays that are sunlight readable, highly reliable, and significantly lighter that CRT technology, as well as Reduced Instruction Set Computer (RISC) based high-performance display generators that have only recently become feasible to implement in a military aircraft. This paper describes the overall subsystem architecture, some detail on the individual elements along with supporting rationale, the manner in which the display subsystem provides the necessary tools to significantly enhance the performance of the weapon system through the vital Operator-System Interface. Also addressed is a summary of the evolution of design leading to the current approach to MMH Operator displays and display processing as well as the growth path that the MMH display subsystem will most likely follow as additional technology evolution occurs.

A variety of Active Matrix Liquid Crystal Displays, AMLCDs, are now being deployed in a broad range of aircraft. The most familiar applications are for flight deck instrumentation and passenger entertainment where the benefits of size, weight and legibility of the flat panel display technology are exploited. These benefits are particularly significant in rotor-wing aircraft where weight is of paramount importance and specifically in those helicopters whose role requires the use of mission displays, this class of display generally being larger than those used for flight deck instrumentation. This paper will describe the features of a set of mission displays which are rendered with AMLCD technology and which are being deployed in the EH- 101 helicopter.

Battelle is under contract with Warner Robins Air Logistics Center to design a Common Large Area Display Set (CLADS) for use in multiple airborne C⁴I applications that currently use unique 19" CRTs. Battelle engineers have determined that by taking advantage of the latest flat panel display technology and the commonality between C⁴I applications, one display set (21" diag. 1280 X 1024) can be designed for use in multiple applications. In addition, common nodular driver and processing electronics are being designed by Battelle to reduce the number of installation-specific circuit card assemblies required for a particular application. Three initial applications include the E-3 (AWACS) color monitor assembly, E-8 (JSTARS) graphics display unit, and ABCCC airborne color display. For these three applications reliability and maintainability are key drivers. The common design approach reduces the number of unique subassemblies in the USAF inventory by approximately 56 to 66 percent. The new design is also expected to have MTBF of at least 3350 hours, and order of magnitude better than one of the current systems. In the JSTARS installation, more than 1400 lbs can be eliminated from the aircraft. In the E-3 installation, the CLADS is estimated to provide a power reduction of approximately 1750 watts per aircraft. This paper will discuss the common large area display set design and its use in a variety of C⁴I applications that require a large area, high resolution, full color display.

The 1970s saw the start of a trend towards integrated digital avionics. In the 1980s, the Air Force's Pave Pillar initiative defined centralized digital processing as the cost- effective approach to tactical avionics. The avionics systems of the two advanced aircraft presently under development, a fixed-wing tactical fighter and an armed scout/reconnaissance helicopter, were based on this architecture. Both platforms relied upon custom, single-purpose hardware and software to generate images for their advanced multifunctional flat panel cockpit displays. The technology to generate real-time synthetic images with common data and signal processors was not available during the development of the platforms. Harris IR&D investigations have focused on an approach that Harris GASD has named the Common Avionics Display Processor (CADP). This programmable device can generate sophisticated images or perform sensor image manipulation and processing. The Common Avionics Display Processor is a general purpose image synthesizer. It consists of software and hardware components configured at run time by a downloaded program. The CADP offers two advantages over custom, special purpose devices. First, it solves a class of problems, not a single one. It can generate many types of images, from alphanumeric to sensor simulation. Only one module type is required for any of these functions. Second, as program schedules become shorter, traditional hardware design time becomes the delivery limiting task. Because both the software and hardware components are programmable at run time, the CADP can adapt to changing requirements without redesign.

Honeywell has been actively involved in the definition of the next generation display processors for military and commercial cockpits. A major concern is how to achieve super graphics workstation performance in avionics application. Most notable are requirements for low volume, low power, harsh environmental conditions, real-time performance and low cost. This paper describes the application of VHDL to the system analysis tasks associated with achieving these goals in a cost effective manner. The paper will describe the top level architecture identified to provide the graphical and video processing power needed to drive future high resolution display devices and to generate more natural panoramic 3D formats. The major discussion, however, will be on the use of VHDL to model the processing elements and customized pipelines needed to realize the architecture and for doing the complex system tradeoff studies necessary to achieve a cost effective implementation. New software tools have been developed to allow 'virtual' prototyping in the VHDL environment. This results in a hardware/software codesign using VHDL performance and functional models. This unique architectural tool allows simulation and tradeoffs within a standard and tightly integrated toolset, which eventually will be used to specify and design the entire system from the top level requirements and system performance to the lowest level individual ASICs. New processing elements, algorithms, and standard graphical inputs can be designed, tested and evaluated without the costly hardware prototyping using the innovative 'virtual' prototyping techniques which are evolving on this project. In addition, virtual prototyping of the display processor does not bind the preliminary design to point solutions as a physical prototype will. when the development schedule is known, one can extrapolate processing elements performance and design the system around the most current technology.

There is a need for a reliable source of high performance large area sunlight readable active matrix liquid crystal displays (AMLCDs) for avionic and military land vehicle applications. Image Quest has developed an avionic display module (ADM) to demonstrate the capability to produce high performance avionic displays to satisfy this need. The ADM is a large area (6.24 X 8.32 inch) display with VGA compatible interface, 640 X 480 color pixels and 64 gray shades per primary color. The display features excellent color discrimination in full sunlight due to a saturated color gamut, very low specular reflectance (< 1%) and high output white luminance (200 fL). The ADM is designed from the glass up to fully meet the avionic and military application and environment. Control over all the display performance parameters including contrast, transmission, chroma, resolution, active size and packaging configuration is ensured because Image Quest produces all of the critical elements of the display. These elements include the a-Si TFT AMLCD glass, RGB color filter matrix, bonding of folded back driver TABs, anti-reflective cover glass, LC heater and integration of high luminance hot cathode backlight with thermal controls. The display features rugged compact packaging, 2000:1 luminance dimming range and wide operating temperature range (-40 to +71 $DRGC). In the immediate future Image Quest plans to expand the development efforts to other similar custom high resolution and high performance avionic display module configurations including 4 X 4 inch delta triad, 6.7 X 6.7 inch delta triad and 16.5 inch diagonal with 1280 X 1024 pixels. Image Quest can deliver up to 10,000 displays per year on a timely basis at a reasonable cost.

AMLCD cockpit displays need to meet more stringent requirements compared with AMLCD commercial displays in areas such as environmental conditions, optical performance and device reliability. Special considerations are required for the manufacturing of AMLCD cockpit displays in each process step to address these issues. Some examples are: UV stable polarizers, wide-temperature LC material, strong LC glue seal, ESS test system, gray scale voltage EEPROM, etc.

Active Matrix Liquid Crystal Displays, AMLCDs, based on Cadmium Selenide Thin Film Transistors, have been developed by Litton for a number of defence/avionics applications. Fabrication processed for the thin film transistor (TFT) arrays, color filters and liquid crystal cell assembly have been developed which enable the end product to meet the difficult environmental and performance specifications of military applications, while maintaining focus on cost and yield issues. The fabrication of the AMLCD products is now transitioning into a new production facility which has been designed specifically to meet the requirements of the defence/avionics marketplace.

As cockpit lighting systems have evolved which implement active matrix liquid crystal displays (AMLCD) into military aircraft, it has become obvious that an extremely large dimming range is necessary to accommodate low level night operation and high ambient sunlight conditions. This range may be as large a 0.03 FtL to 200 FtL (6667:1) over the display field of view. This is a much larger range than previously exhibited by typical hot cathode fluorescent lamps. Additionally, performance enhancements are necessary to achieve the high contrast required for sunlight operation in a military environment. These are also complicated by the requirements to start rapidly and operate reliably in environments of -54 degree(s)C to +71 degree(s)C. A significant research and development program has been dedicated to advance the backlight and display technology to achieve the desired performance. This paper will present the results of this effort. It includes data from the benchmarked start through several breadboarded backlight and display enhancements.

The paper is based on a 6 X 8 inch backlight assembly designed for a military requirement including NVG compatibility. Measured data for luminance and input power is reported across a temperature range of -40 to +55. The paper highlights the state of the art achieved for the fluorescent cavity design approach implemented by SAIC. The data demonstrates the relationships between light output, input power and temperature. The data suggest engineering requirements for thermal control of LCD displays and system performance expectations at the extreme edges of the temperature range.

An all-digital, 5 V input, 50 Mhz bandwidth, 10-bit resolution, 128- column, AMLCD column driver IC has been designed and tested. The 10-bit design can enhance display definition over 6-bit nd 8-bit column drivers. Precision is realized with on-chip, switched-capacitor DACs plus transparently auto-offset-calibrated, opamp outputs. Increased resolution permits multiple 10-bit digital gamma remappings in EPROMs over temperature. Driver IC features include externally programmable number of output column, bi-directional digital data shifting, user- defined row/column/pixel/frame inversion, power management, timing control for daisy-chained column drivers, and digital bit inversion. The architecture uses fewer reference power supplies.

High voltage power supplies (HVPS) have traditionally been among the least reliable components in airborne display electronics. NAVMAT P- 4855-1A, a power supply design manual adopted by the U.S. Navy in 1989, highlighted the source of these problems in industry's failure to apply appropriate methods for high voltage design, development and materials selection. Also, the nature of airborne HVPS is such that MTBF prediction using MIL-HDBK-217 has shown very little correlation to actual field performance. These problems continue today. In recent years, ELDEC has developed a methodology to systematically evaluate and improve the design and long term reliability of high voltage power supplies. This methodology has been successfully applied under a recent Air Force CRT PRAM contract to improve HVPS reliability in AWACS aircraft situation displays. The accelerated testing portion of the methodology has been recommended to the Air Force for adoption as a standard to be used in procurement of future high voltage power supplies. Elements of the methodology are described in this paper.

Void formations in liquid crystal displays are not a new phenomenon, however, the documentation of such failures has not been extensive or readily available. The context of this paper is to cover the background of void formations within liquid crystal displays and concentrate on the 'unknown' void formation discovered in dichroic LCDs. Even though the origin of the void is not known, there are two catalyst necessary to create this type of void. The application of the information should be incorporated into the development of other flat-panel technologies to be used in military and commercial aviation.

The Liquid Crystal Display provides a necessary information interface to pilots from their aircraft and equipment. In order to successfully complete mission requirements, increased amounts of information are made available to pilots. The control of commercial and military air transports, weapons systems and ordinance that contain the highest technology electronics requires pilots to have instant access to large amounts of data. Mechanical dials and 'steam gauges' alone do not have the capability to provide that data. Operational readiness comes with a need for all display systems to have the utmost availability, reliability and maintainability. Original specifications developed from the initial use of smaller fixed format liquid crystal displays have been reproduced over the years with little specification maintenance or attention to actual environmental demands that may or may not have been apparent with mechanical dials (white paint on black dials). As the Liquid Crystal Display grows increasingly important in the aircraft, the need for improved reliability increases. The examples that follow will suggest that further definition is needed on exactly how and where the displays are to be used, and in what environments they will be required to survive. With cooperative efforts of among equipment designers, display designers, and specification writers, new and updated specifications targeted directly for liquid crystal display systems will help to achieve cost effective, high reliability information display systems for users.

Liquid crystal displays by virtue of their flat profile, low volume and low power offer the user a number of advantages over CRTs, without compromising on the image quality. High definition (1000 line) flat panel displays enhance image recognition, which improves the viewer's ability to resolve images. High definition displays are required over a wide spectrum of sizes for HMDs through HDDs, to multifunction consoles. These size and complexity requirements may be uniquely met with ferroelectric liquid crystal display (FLCD) technology. The fast line address times (l.a.t. approximately equals 20 microsecond(s) ) may be traded off to meet complexity, color and grayscale. This paper describes the latest developments in FLCD design to produce temporal and spatial dither grayscale. These exploit new developments in material response times and fast drive schemes developed at DRA Malvern. The increased speed provided by the Malvern drive schemes also allows color to be implemented in a temporal manner similar to temporal grayscale. A new method to add color to existing fast displays using a frame sequential technique is also described.

A new approach to backlighting in LCDs has been developed which is particularly suitable for the demanding requirements of avionics applications. Details of this technology and performance figures for specific cockpit applications are presented.

A prototype 10 inch flat panel Planar Optic display, (POD), screen has been constructed and tested. This display screen is comprised of hundreds of planar optic glass sheets bonded together with a cladding layer between each sheet where each glass sheet represents a vertical line of resolution. The display is 9 inches wide by 5 inches high and approximately 1 inch thick. A 3 milliwatt HeNe laser is used as the illumination source and a vector scanning technique is employed.