An evaluation was carried out of the first prototype (LV-3) of a new night vision device, which incorporates visual field expansion through minification (Minified Augmented-View), to provide feedback for continuing development. Six subjects with night blindness completed visual function measurements and indoor mobility assessments without a device, with the LV-3 and with a commercially available comparison device (the Multi-Vision) at light levels representative of well lit and poorly lit streets. Device performance and potential benefits in real-world situations were evaluated at four outdoor locations (well lit to very dark). Results indicate that the see-through nature and spectacle-frame mounting of the LV-3 address some of the cosmetic and ergonomic disadvantages of currently available devices; however insufficient light sensitivity of the prototype camera limited LV-3 performance. With improved camera sensitivity and full implementation of the Minified-Contours Augmented-View concept in the next prototype, patients might be able to make better use of the novel field expansion and vision multiplexing features to aid outdoor night mobility.

Vision loss typically affects either the wide peripheral vision (important for mobility), or central vision (important for seeing details). Traditional optical visual aids usually recover the lost visual function, but at a high cost for the remaining visual function. We have developed a novel concept of vision-multiplexing using augmented vision head-mounted display systems to address vision loss. Two applications are discussed in this paper. In the first, minified edge images from a head-mounted video camera are presented on a see-through display providing visual field expansion for people with peripheral vision loss, while still enabling the full resolution of the residual central vision to be maintained. The concept has been applied in daytime and nighttime devices. A series of studies suggested that the system could help with visual search, obstacle avoidance, and nighttime mobility. Subjects were positive in their ratings of device cosmetics and ergonomics. The second application is for people with central vision loss. Using an on-axis aligned camera and display system, central visibility is enhanced with 1:1 scale edge images, while still enabling the wide field of the unimpaired peripheral vision to be maintained. The registration error of the system was found to be low in laboratory testing.

We have proposed a novel concept of vision multiplexing for the visually impaired -superimposing contour images over their natural view of a scene or over original images presented on a TV screen. We have implemented the concept using an optical see-through head mounted display to provide either visual field expansion to patients with peripheral field loss or vision enhancement to patients with central vision loss. We have also implemented the concept in a video player with dynamic magnification for patients with central vision loss. Results of initial testing in the lab and on the street are promising. KeywordsHead mounted display; multiplexing; vision impairment BackgroundWith normal vision we enjoy the benefits of a wide field of view, primarily used for navigation, orientation, and obstacle avoidance, together with high-resolution capabilities that enable discrimination of fine details. Visual impairments due to disease or injury usually affect only one of these aspects, either restricting the wide peripheral visual field (VF) in conditions such as retinitis pigmentosa (RP) and glaucoma, or damaging the high-resolution fovea in conditions such as age-related macular degeneration (AMD).When peripheral VF loss is severe (leaving useful VFs of less than 20° in diameter -tunnel vision), a patient's mobility can be affected due to reduced ability to spot obstacles and difficulties in navigation. When patients experience central vision loss, the ability to discriminate fine detail is affected due to an increase in contrast threshold for high-frequency patterns, which causes difficulties with reading regular-sized print and recognizing faces and watching TV.Traditional optical devices for the visually impaired restore, at least partially, the lost visual ability, but at a high cost for the remaining functionality. For example, magnification improves NIH Public Access Author ManuscriptInt J Artif Intell Tools. Author manuscript; available in PMC 2010 June 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript resolution but inherently limits the field of view. Similarly, minifying devices increase the field of view, but cause a loss of resolution in addition to spatial distortions, and restriction of freescanning eye movements. Our novel design approach, called "vision multiplexing", attempts to avoid or reduce these limitations by combining both the wide field-of-view and the highresolution capabilities in devices in ways that permit these functionalities to be both separable and useful 1 . Augmented vision systems lend themselves to vision multiplexing. In this paper we report on the development and preliminary evaluations of two augmented vision systems that implement spatial multiplexing via superposition 1 (See Fig. 1).The first system incorporates a head-mounted display (HMD) and has applications for patients either with tunnel vision or central vision loss. Contour images derived from a miniature video camera are presented in an optical see-through HMD. For patients with tunnel ...

This paper reports on progress in the area of hardware for wearable computing. Our specific interest is in reducing conventional head-mounted display systems to eyeglass scale. We report here the successful demonstration of an ergonomic eyeglasses-based display. We present some of the general considerations in the design of such eyeglasses and briefly review our approach and initial findings.

Abstract— We report the development of a new approach to design and fabrication of eyeglass‐based displays. The principal feature of this technique is the incorporation of an optical relay between the display and the eye within the eyeglass lens, and the incorporation of a display within the eyeglass temple. Color eyeglass‐based displays are described.