This PDF file contains the front matter associated with SPIE Proceedings Volume 6955, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

Night vision goggles have been in use for many years and limitations in their use have been well studied through training research and flight experience. However, advances in technology have led to improvements in NVG display capabilities and in some cases helmet mounted display (HMD) technology has begun replacing NVG systems. These advances have led to an increase in the complexity of imaged scene content, thus requiring a greater level of cognitive effort for interpretation, especially when compared to the images provided by current NVG systems. In some cases the complexity of visual imagery has resulted in systems not being classified as operationally suitable. This presentation will focus on a few of the problems noted while testing some of these advanced systems. Topics will include: added complexity of imagery in wide-field-of-view (WFOV) NVG systems, effects due to imagery created by sensors displaced from the normal eye position (increased interocular separation), effects due to imagery projected onto seethrough visor designs, and effects resulting from cockpit design/geometry (e.g., location and design of large-format head-down displays, and the position of structures such as window frames). Training concerns and potential mitigation strategies for HMD design concepts will also be covered. The issues discussed are important for manufacturers to understand during the early design phase, and for testers to understand during developmental or operational testing.

High-resolution compact reflective liquid crystal displays have been developed in recent years. The eyepiece optical system is compact, but it remains difficult to achieve a very wide FOV using LCDs of this type. To achieve a wide FOV, it is preferable to use an optical system in which an intermediate image is formed. However, this intermediate-image system ends up making displays very large compared to those using the eyepiece optical system. To solve this problem, we have developed a new optical system, called the "shuttle" optical system, in which a shuttle (bidirectional) optical path is formed in a decentered FFS (free-form surface) optical system with an intermediate image. The shuttle optical system allows the intermediate-image optical system to be compact. Through the use of this shuttle optical system as well as electronic distortion-compensation, we have developed a high-resolution SXGA compact video see-through HMD with a high FOV of 76 degrees for mixed reality.

The Aviation Combined Arms Tactical Trainer (AVCATT) reconfigurable manned module simulator is the Army's premier deployable helicopter collective training simulator. While successful, improvements to the visual display performance for the Out-The-Window (OTW) visual system have been desired. In a recent selection evaluation, Rockwell Collins' SR100A HMD was chosen for the upgrade, improving display resolution, reducing weight, enhancing comfort and increasing ruggedness. This paper will compare the current XL100A HMD with the improved performance of the new SR100A system.

Selected to meet the stringent requirements of the Gripen swing-role combat aircraft, the Cobra Helmet Mounted Display System, has been integrated as a key component to the Gripen weapon delivery system. Saab Aerosystems has since 2003 together with BAE System been developing the Cobra HMD and in parallel integrating the system in Gripen for South Africa. Work is currently done to prepare other customer for the Cobra HMDS. This paper will highlight some technical challenges and experiences with integrating a HMDS in a small cockpit environment as in Gripen and present an overview of the Cobra HMD design and installation. Furthermore the paper will discuss the importance of having the pilots and users involved during the design phase and throughout the development.

TopOwl® is an original concept of binocular Helmet Mounted Sight and Display system (HMSD) for helicopters, where two Image Intensifier Tubes (IIT) are integrated on the headgear and optically coupled to the clear visor placed in front of the pilot's eyes. Thales recently developed a new version of its TopOwl®'s Display Module with the objective to have an HMSD capable to achieve all kind of missions up to the darkest night levels. The main enhancements are the redesign of the optical combination, the use of new optical materials and of latest generation of optical design tools. Two flyable prototypes of this new design were manufactured. A performance assessment has been conducted, showing a significant improvement of the night vision performances, reaching performances equivalent to those of last issued NVGs. These evaluations are being completed by different flight test evaluations.

Helmet-Mounted Displays (HMDs) do not allow the pilot to change transmission level of a visor transitioning from high to low light levels. A variable-transmittance visor (VTV) is a possible solution. The Eclipse Variable Electrochromic Device (EclipseECD^TM) is well suited for these light modulation applications. The EclipseEC^TM modulates light intensity by changing the transmission level under an applied electric field. The optical density may be continuously changed by varying voltage. EclipseECD^TM is comprised of vacuum deposited layers of a transparent bottom electrode, an active element, and a transparent top electrode, incorporating an all, solid-state electrolyte. The solid-state electrolyte eliminates possible complications associated with gel-based technologies, the need for lamination, and any additional visor modifications. The low-temperature deposition process enables direct application onto HMD flight visors. Additionally, the coating is easily manufactured; can be trimmed, has near spectral neutrality and fails in the clear (bleached) condition. Before introducing VTV technology to the warfighter, there are numerous human factors issues that must be assessed. Considerations include optical characteristics such as transmissive range, haze, irising, internal reflections, multiple imaging, user controllability, ease of fit, and field of view. Advanced materials tailoring coupled with meeting critical criteria will help ensure successful integration of VTV technology.

OLED displays have been known to exhibit high levels of performance with regards to contrast, response time, uniformity, and viewing angle, but a lifetime improvement has been perceived to be essential for broadening the applications of OLED's in the military and in the commercial market. As a result of this need, the US Army and eMagin Corporation established a Cooperative Research and Development Agreement (CRADA) to improve the lifetime of OLED displays. In 2006, eMagin Corporation developed long-life OLED-XL devices for use in their AMOLED microdisplays for head-worn applications, and RDECOM CERDEC NVESD ran life tests on these displays, finding over 200% lifetime improvement for the XL devices over the standard displays. Early results were published at the 2007 SPIE Defense and Security Symposium. Further life testing of XL and standard devices at ambient conditions and at high temperatures will be presented this year along with a recap of previous data. This should result in a better understanding of the applicability of AMOLEDs in military and commercial head mounted systems: where good fits are made, and where further development might be needed. This is a continuation of the paper "Life test results of OLED-XL long-life devices for use in active matrix organic light emitting diode (AMOLED) displays for head mounted applications" presented at SPIE DSS in 2007.

A new approach for optical Head Motion Tracker (hereafter HMT) is shown. In existing magnetic HMT, it is inevitable to conduct pre-mapping in order to obtain sufficient accuracy because of magnetic field's distortion caused by metallic material around HMT, such as aircrafts and vehicles. Optical HMT is commonly known as mapping-free tracker; however, it has some disadvantages in comparison with magnetic HMT. We have succeeded to develop a new optical HMT, which can overcome those disadvantages by integration with two area cameras, optical markers and inertial sensors with simple algorithm.

We report progress in developing a 0.97-in diagonal AMLCD with a full color SXGA resolution. A 1280×1024×3 dot array was developed with integrated color pixel filters to create an SXGA color pixel array. These displays are fabricated on 8-inch SOI wafers and transferred to glass wafers to produce transmissive liquid crystal displays. Improvements have been made in this AMLCD to bring the fabrication process to manufacturing. Fabricating a 3.9 million pixel dot display on a 1-inch die required a new display design and fabrication in an 8-inch wafer line. The 8-inch process provided enhanced process capabilities and tighter design rules to achieve good performance and reasonable starting yields. An ASIC driver and ultra thin efficient backlight were developed to miniaturize the display module and to reduce total power to < 750mW for soldier mounted applications. Total package size is less than 0.5 in³. The ASIC will also drive Kopin SVGA and VGA color displays singly or in pairs for binocular applications. An end-to-end 8-inch wafer process was established at the wafer foundry and at Kopin. A 3-year manufacturing technology insertion program (Mantech) has begun to optimize the 8-inch line processes and the SXGA color display. Meeting yield and performance goals will reduce display cost and enable systems performance goals. Key results include vivid, high-resolution color, wide viewing angles and low power operation. Performance data and specifications will be presented.

In the late 1970s the U.S. Army developed the Integrated Helmet and Display Sighting System (IHADSS), which is a helmet-mounted display (HMD) for use in the AH-64 Apache helicopter. The helicopter and the system were designed with the Cold War in mind such that the Apache would be able to stand off far from the frontlines and attack deep target-primarily tanks-before they could engage our ground forces. The design used a right-sided monocular display optical system that was intended to reduce head-supported weight. This novel monocular design introduced a number of issues that had the potential of causing visual perception problems for pilots. Since the initial fielding of the Apache in the early 1980s, numerous reports have appeared in the literature that evaluated realized visual complaints voiced by Apache aircrew. In this review, the authors provide a summary of seminal reports, surveys, and experiments conducted over the past three decades. The extant literature described investigated these visual issues as the Apache's mission has evolved from the stand-off engagement tactics of the Cold War to the new Apache missions of close air support, deep attack, and raids currently occurring in the Global War on Terrorism.

The Integrated Helmet and Display Sighting System (IHADSS) helmet-mounted display (HMD) has been flown for over a quarter of a century on the U.S. Army's AH-64 Apache Attack Helicopter. The aircraft's successful deployment in both peacetime and combat has validated the original design concept for the IHADSS HMD. During its 1970s development phase, a number of design issues were identified as having the potential of introducing visual perception problems for aviators. These issues include monocular design, monochromatic imagery, reduced field-of-view (FOV), sensor spectrum, reduced resolution (effective visual acuity), and displaced visual input eye point. From their diverse perspectives, a panel of four experts - an HMD researcher, a cognitive psychologist, a flight surgeon, and a veteran AH-64 aviator - discuss the impact of the design issues on visual perception and related performance.

Providing both I² (image intensified) and FLIR (forward looking infrared) images on a helmet-mounted display (HMD) requires perceptual design tradeoffs. Primary considerations center on the number, type, and placement of sensors. Perceptual drivers for these tradeoffs are derived from monocular versus biocular/binocular displays and offset of the sensors from the design eye. These conditions can create binocular rivalry, perceptual perspective distortion or hyperstereopsis, a binocular perceptual distortion that occurs when the sensors are positioned further apart than the interpupillary distance (IPD). Each of these perceptual tradeoff considerations is discussed.

Distance judgments in virtual environments and Head-mounted Displays (HMD) systems are generally underestimated compared with judgments in the real world. Some visual depth cues may be absent or modified, according to the technology used. After a brief review of the literature pertaining to the representation of depth in Helmet-Mounted Displays, we explore two possible causes for the reduced distance perception in virtual environments: the increased interocular separation (or hyperstereopsis) and the reduction of the field of view. Some laboratory and training ground data are reported. The effective influence of each factor on space perception is discussed.

Field of view (FOV) restrictions are known to impair human performance for a range of different tasks. However, the effects of FOV restrictions on human locomotion through a complex environment are still not clear. This is particularly important for the development and deployment of FOV restricting devices like Head Mounted Displays (HMDs), which generally have FOVs that are much smaller than the unrestricted FOV. We investigated the effects of both horizontal and vertical FOV restrictions on the walking speed and head movements of participants manoeuvring through complex 3D obstacle courses. All FOV restrictions tested significantly increased the time needed to complete the courses, compared to the unrestricted condition. The time needed to traverse a course was significantly longer for a vertical FOV of 18° than for a vertical FOV of 48°. For a fixed vertical FOV size, the traversal time was constant for horizontal FOV sizes ranging between 75° and 180°, and increased significantly for the 30° horizontal FOV condition. The implications of the current findings for the development of devices with FOV restrictions (like HMDs) are discussed.

Previous research has repeatedly shown that people can find a visual target significantly faster if spatial (3D) auditory displays direct attention to the corresponding spatial location. However, previous research has only examined searches for static (non-moving) targets in static visual environments. Since motion has been shown to affect visual acuity, auditory acuity, and visual search performance, it is important to characterize aurally-aided search performance in environments that contain dynamic (moving) stimuli. In the present study, visual search performance in both static and dynamic environments is investigated with and without 3D auditory cues. Eight participants searched for a single visual target hidden among 15 distracting stimuli. In the baseline audio condition, no auditory cues were provided. In the 3D audio condition, a virtual 3D sound cue originated from the same spatial location as the target. In the static search condition, the target and distractors did not move. In the dynamic search condition, all stimuli moved on various trajectories at 10 deg/s. The results showed a clear benefit of 3D audio that was present in both static and dynamic environments, suggesting that spatial auditory displays continue to be an attractive option for a variety of aircraft, motor vehicle, and command & control applications.

As pointed out by Kotulak, vergence/accommodation mismatch in Night Vision Systems, usually due to misadjustments of eyepiece focus, is sometimes a source of visual performance decrement. The increased separation between sensors existing in some modern binocular Helmet Mounted Display systems, creating "hyperstereopsis", was also identified to be potentially responsible for decreased performance at distances less than 5 meters. Based upon basic knowledge pertaining to vergence and accommodation mechanisms, a study was performed using a sensory approach, with the goal of better understanding the problem of dissociation between accommodation and convergence. In this study, different conditions of interocular separation (nominal IPD, X3, X4) and viewing distances (6m, 4m, 2m) were used. Six subjects participated in the experiment and were asked to view Landolt C charts using NVGs and specially developed optical tools allowing changes to sensor separation. The results show that, with a fixed eyepiece focus at 10m, the decrease in resolution performance is roughly proportional to the interocular separation when looking at short distances. A fixed focus at a distance of 4m considerably reduces the conflict and results in improved resolution for increased separation conditions. An additional experiment was conducted to investigate the setting of objectives lenses focus at infinity (nominal landing condition). With this setting, for visual acuity test, the decrease in resolution at short distance was such that effects of the mismatch between accommodation and convergence are no longer apparent regardless of interocular separation.

Head mounted displays (HMD) are finding increasing use in a great many applications. These HMDs provide information ranging from a simple alphanumeric to complex graphical renderings of real or synthetic worlds. Some of these HMDs are opaque so that the user's vision is completely confined to what the HMD provides; others are see-through so that elements of the HMD may be superimposed simultaneously with the external world. Some see-through HMD applications incorporate graphical elements intended to be in some calibrated registration with elements of the external world such that the relation between the graphic and the world embodies the relevant information. For such displays to function as intended the head yaw, pitch, and roll are important. The present paper reports measures of head yaw, pitch, and roll when the head is in a straight ahead orientation. Volunteers oriented to either a visual or auditory target stimulus presented under a variety of conditions. For some conditions with the visual target, the visual field was restricted to less than 5 degrees (°); for other conditions vision was unrestricted. The auditory targets were presented in complete darkness. At the start of each trial, an acoustic warning signaled the volunteer to turn the head from an initial off-axis yaw and pitch to a target stimulus that defined the straight ahead yaw and pitch. Note that the stimulus left head roll completely undefined. Within- and between-subject head yaw, pitch, and roll statistics are reported and compared for the various stimuli.

Head- and helmet-mounted displays have been used in hands-free viewing applications and as part of visually coupled systems for aircraft simulation and flight applications. Successfully done, they can improve situation awareness by freeing the user from the need to stare "heads-down" at a display for information to create a working model of the world around them. This allows them to explore and navigate through the world while at the same time reducing workload, leaving precious cognitive resources for other, more demanding tasks. Building upon recent developments in neuroergonomics and augmented cognition, this paper will discuss situation awareness and the potential for reducing workload by cognitively "pre-digesting" information, by using real-time operator monitoring to invoke automation and by presenting in additional sensory modes.

Different night vision goggle image intensification technologies were tested to compare goggle performance in low light conditions. A total of four different night vision goggles were tested in a laboratory dark room. The laboratory tests consisted of viewing Landolt acuity stimuli of different contrast levels with each set of goggles and without the goggles in full light conditions (baseline performance). The results from the laboratory testing indicated that there were significant differences in acuity between the NVGs, particularly for low contrast targets. These data suggest that NVG standards developed using high contrast targets, even in low light conditions may not provide the full story of how the NVG will perform in flight.

This document provides an overview of helicopter flight-test methods used to evaluate night vision goggles at the National Research Council of Canada's Institute for Aerospace Research. These techniques have been used to examine the performance of display systems in actual field conditions. The flight evaluations were based, in large part, on standard flight test maneuvers and rating systems outlined in Aeronautical Design Standard ADS-33. The document describes NVG test maneuvers developed from ADS-33 principles, including a high hover, a mirror C, a vertical descent, a parallel lateral translation, a turn about the tail, a confined area staged landing, a brown-out/white-out simulation and a lit pirouette. The overview also comprises a description of methods for controlling the cueing environment. These methods include an appropriate selection of maneuvers as well as devices for limiting pilot vision such as goggles with filters and apertures, and other devices. The paper concludes with a short discussion on the merits of developing accurate in-flight tests capable of resolving performance differences among displays.

The US Air Force and US Navy are cooperatively developing and demonstrating a wide field of view, night vision, helmet mounted cueing system called Night Vision Cueing and Display. This paper addresses the USAF path to safety of flight qualification of the device to include assessment of the display quality, aircraft compatibility, environmental tolerance, and ejection safety. The variety of tests accomplished will be briefly discussed to include key challenges that were met and overcome. Also addressed is developmental and operational flight testing. Pilot assessments of the system are discussed with emphasis on the aircrew interface and challenges with a newly designed, ejection safety enhancing visor. Finally, joint service plans for the system are addressed.

A novel type of stereoscopic Helmet Mounted System for simultaneous user localization and mapping applications is described. This paper presents precise real time volume data reconstruction. The system is designed for users that need to explore and navigate in unprepared indoor environments without any support of GPS signal or environment preparation through preinstalled markers. Augmented Reality features in support of self-navigation can be interactively added by placing virtual markers in the desired positions in the world coordinate system. They can then be retrieved when the marker is back in the user field of view being used as visual alerts or for back path finding.

The primary means by which air traffic tower controllers obtain information is through direct out-thewindow viewing, although a considerable amount of time is spent looking at electronic displays and other information sources inside the tower cab. The Air Force Research Laboratory sponsored the development of a prototype Augmented Reality Binocular System (ARBS) that enhances tower controller performance, situation awareness, and safety. The ARBS is composed of a virtual binocular (VB) that displays real-time imagery from high resolution telephoto cameras and sensors mounted on pan/tilt units (PTUs). The selected PTU tracks to the movement of the VB, which has an inertial heading and elevation sensor. Relevant airfield situation text and graphic depictions that identify airfield features are overlaid on the imagery. In addition, the display is capable of labeling and tracking vehicles on which an Automatic Dependent Surveillance - Broadcast (ADS-B) system has been installed. The ARBS provides air traffic controllers and airfield security forces with the capability to orient toward, observe, and conduct continuous airfield operations and surveillance/security missions from any number of viewing aspects in limited visibility conditions. In this paper, we describe the ARBS in detail, discuss the results of a Usability Test of the prototype ARBS, and discuss ideas for follow-on efforts to develop the ARBS to a fieldable level.

One of the difficulties that arise in trying to navigate through or interact with a 3D virtual environment is the fact that the standard 2D mouse with only two degrees of freedom does not lend itself to being used effectively where six degrees of motion are possible. Through the use of both a mouse and keyboard, one is able to interact in three degrees but never in all six at the same time, thus making interaction cumbersome at best. We test out a series of both commercial-off-the-shelf and in-house prototype tangible user interfaces (TUIs) to characterize multiple interaction methods within a virtual environment for command and control applications. Various aspects of navigation, including moving through the virtual world, as well as directly manipulating the world itself, are compared. We attempt to determine which interfaces are most appropriate for specific types of command and control tasks. We conclude with recommendations for the use of TUIs as well as ideas for future research.