Patients with visual field loss have difficulty in mobility due to collision with pedestrians/obstacles from the blind side. In order to retrieve the lost visual field, prisms which deflect the field from the blind to the seeing side, have been widely used. However, the deflection power of current clinical Fresnel prisms is limited to ~30° and only provides a 5° eye scanning range to the blind side. This is not sufficient to avoid collision and results in increasing demands for a device with a higher power. In this paper, we propose a novel design and optimization of a higher power prism-like device (cascaded structure of mirror pairs filled with high refractive index) and verify enhanced expansion of up to 45° in optical ray tracing and photorealistic simulations.Individuals with visual field loss report collisions with other pedestrians/objects and tripping over obstacles, and are commonly not permitted to drive. All of these factors severely restrict their mobility and quality of life. Peripheral visual field loss, tunnel vision (severe peripheral field constriction to < 20° of residual central field), maybe due to retinal diseases such as retinitis pigmentosa, choroideremia, and advanced glaucoma [1,2]. The loss of half of the visual field in both eyes on the same side (Homonymous hemianopia, HH), which is a common peripheral field loss, can be caused by brain injuries such as stroke, trauma, or tumors [3][4][5][6].Among various efforts to help the patients with visual field loss as described above, prism glasses have been long considered one of the simplest, most effective, and helpful devices for field expansion, shifting (deflecting) the field from the blind side (prism base side) to the seeing side of the patient with visual field loss. Throughout previous studies, peripheral prism glasses [4] to avoid confusions in the central visual field are established as an effective field expansion device for field loss patients in walking [2] and driving [7]. Regarding the concept of visual field expansion, it is obvious that larger deflection power can deliver more *

To provide two-eyed views with one device, stereoscopic 3D (S3D) displays interlace the two views either temporally or spatially: temporal interlacing (TI) alternates the two views in time with full resolution, while spatial interlacing (SI) presents the two views simultaneously but with half resolution for each eye. We investigate the effect of interlacing methods on image quality through a psychophysical experiment. We compared four experimental conditions: three S3D interlacing methods (TI, SI with raw sampling, and SI with vertical interpolation), and one nonconventional interlacing method (vertical interpolation). The stimuli were 10 natural stereo images presented at nine levels of pixel sizes (0.64, 0.78, 0.89, 1.00, 1.28, 1.55, 1.78, 2.00, and 2.56 arcmin). To test the effect of interlacing methods per se, we provided all the experimental conditions to the subjects using a single experimental setup: a mirror stereoscope. The results show that TI does not degrade the image quality for any pixel size. SI degrades the image quality when the pixel size is relatively large, but the effect of the two SI methods does not differ significantly. Comparison of SI methods against the vertical interpolation method implies that the primary cause of the degradation in image quality for SI methods is the visibility of the interlacing pattern rather than the loss of high-frequency information.

No abstract

An augmented reality (AR) lightfield display can provide three-dimensional (3D) images at the locations of real objects. However, a conventional AR lightfield display has a few disadvantages in that its 3D resolution is poor and it is bulky in form owing to the use of an optical combiner or relay optics. In this paper, we propose a novel method to realize an AR lightfield display using a transparent display and an active pinhole array (APA) to enhance both the 3D resolution and visibility of real objects. An experimental demonstration verifies that the proposed method is appropriate for smart window applications. INDEX TERMS Augmented reality, lightfield reconstruction, active pinhole array.

In this paper, a method to construct a directional-backlight unit system to separate the left-eye image and the right-eye image by adopting a double-slit barrier array is proposed to enhance the perceived quality of the realized 3D image. Additionally, the two-dimensional/three-dimensional convertible function is also realized by adopting an active diffuser to the spatial interlacing directional-backlight system.