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In this article, we propose a waveguide-based binocular Maxwellian near-eye display for implementing realistic augmented reality. Contrasting with conventional binocular near-eye displays that typically use two micro-displays, our proposed configuration uniquely utilizes a single micro-display to present binocular images. The key optical component in our design is a polarization-dependent grating that deflects incident light to different directions depending on its circular polarization state. Additionally, by using a non-conventional out-coupler, namely, a pin-mirror holographic optical element array, we address the vergence-accommodation conflict issue, which is a primary cause of visual discomfort in conventional near-eye displays. The field of view enhancement by using a set of pin-mirror holographic optical elements is also demonstrated.

Staphylococcus aureusis an important pathogen implicated in various diseases, including staphylococcal food poisoning. Bacteriocins are considered safe and effective antimicrobial substances for the prevention of the growth of pathogenic bacteria. In this article, we describe the purification and characterization of pasteuricin, a novel bacteriocin produced by Staphylococcus pasteuriRSP-1. A cell-free supernatant of S. pasteuriRSP-1 exerted strong antimicrobial activity against staphylococci, including methicillin-resistant S. aureus(MRSA), and gram-positive bacteria. The loss of antimicrobial activity upon treatment with proteolytic enzymes confirmed the proteinaceous nature of pasteuricin. A rapid and pronounced bactericidal effect of pasteuricin was confirmed by a live-dead bacterial viability assay. To our knowledge, pasteuricin is the first reported S. pasteuribacteriocin that inhibits S. aureus. Because pasteuricin is characterized by strong antimicrobial activity and high stability, it has potential as an alternative antimicrobial agent to antibiotics.

In light field microscopy (LFM), the F-number of the micro lens array (MLA) should be matched with the image-side F-number of the objective lens to utilize full resolution of an image sensor. We propose a new F-number matching method that can be applied to multiple objective lenses by using an elastic MLA. We fabricate an elastic MLA with polydimethylsiloxane (PDMS) using a micro contact printing method and address the strain for the F-number variation. The strain response is analyzed, and the LFM system with the elastic MLA is demonstrated. Our proposed system can increase the F-number up to 27.3% and can be applied to multiple objective lenses.

The wavefront printer records a volume-reflection hologram as a two-dimensional array of elemental holograms from computer-generated holograms (CGHs) displayed on a spatial light modulator (SLM). The wavefront coming from the object is extracted by filtering in the spatial-frequency domain. This paper presents a method to improve color reproduction in a wavefront printer with spatial division of exposures at primary colors, by adaptive partitioning of the SLM in accordance with the color content encoded in the input CGHs, and by the controllable change of exposure times for the recording of primary colors. The method is verified with a color wavefront printer with demagnification of the object beam. The quality of reconstruction achieved by the proposed method proves its efficiency in eliminating the stripe artifacts that are superimposed on reconstructed images in conventional mosaic recording.

A compact collimated display system using an aspherical screen with a concave mirror is proposed. As the collimated display can provide a long viewing distance for the observer, it is commonly used for personal virtual flight simulators. To deliver a collimated image, the conventional collimated display requires a large system, but by using an aspherical screen with a concave mirror, the system size can be diminished. In this paper, a method of designing the compact collimated display system is demonstrated with simulation and experiment results. Also, a floating display and a depth camera for detecting hand gestures were combined with the proposed system for interaction.

A novel system of optical see-through augmented reality (AR) is proposed by making use of a holographic optical element (HOE) with full-color and lens-array functions. The full-color lens-array HOE provides see-through property with three-dimensional (3D) virtual images, for it functions as a conventional lens array only for Bragg-matched lights. An HOE recording setup was built, and it recorded a 30  mm×60  mm sized full-color lens-array HOE by using the techniques of spatial multiplexing for large-area recording and wavelength multiplexing for full-color imaging. The experimental results confirm that the suggested full-color lens-array HOE can provide the full-color 3D virtual images in the optical see-through AR system.

We propose a single-shot incoherent holographic imaging technique that adopts self-interference incoherent digital holography (SIDH) with slight tilt of the plane mirror in the optical configuration. The limited temporal coherence length of the illumination leads the guide-star hologram of the proposed system to have a Gaussian envelope of elliptical ring shape. The observation shows that the reconstruction by cross correlation with the guide-star hologram achieves better quality than the usual propagation methods. Experimentally, we verify that the hologram and 3D reconstruction can be implemented incoherently with the proposed single-shot off-axis SIDH.

Novel integral floating three-dimensional (3D) display methods are proposed for implementing an augmented reality (AR) system. The 3D display for AR requires a long-range focus depth and a see-though property. A system that adopts a concave lens instead of a convex lens is proposed for realizing the integral floating system with a long working distance using a reduced pixel pitch of the elemental image. An investigation that reveals that the location of the central depth plane is restricted by the pixel pitch of the display device is presented. An optical see-through system using a convex half mirror is also proposed for providing 3D images with a proper accommodation response. The concepts of the proposed methods are explained and the validity of system is proved by the experimental results.

Accommodation response of super-multiview display device, which is implemented to provide horizontal-only parallax, has been investigated. Because of astigmatic characteristic of such display, the focal points of horizontal and vertical directions differ in longitudinal direction. Assuming that the accommodation response to the astigmatic image follows the distance where the average of bandwidths in vertical and horizontal direction becomes the maximum, numerical calculations presented that the accommodation restrictedly follows three-dimensional point near the display panel. To verify the consequence obtained by numerical calculations, experiments has been performed using keratometer to measure the accommodation under the situation similar to horizontal-only super-multiview display. The images focused by a cylindrical lens have been provided as stimuli to avoid argues related to the resolution of pixel pitch of display panel. The measured results show that the accommodation response restrictedly follows astigmatic image as expected by numerical calculations, however the quantitative investigation is still needed.

Recent trends in three-dimensional (3D) display technologies are very interesting in that both old-fashioned and up-to-date technologies are being actively investigated together. The release of the first commercially successful 3D display product raised new research topics in stereoscopic display. Autostereoscopic display renders a ray field of a 3D image, whereas holography replicates a wave field of it. Many investigations have been conducted on the next candidates for commercial products to resolve existing limitations. Up-to-date see-through 3D display is a concept close to the ultimate goal of presenting seamless virtual images. Although it is still far from practical use, many efforts have been made to resolve issues such as occlusion problems.

Computational reacquisition for real 3D object in integral imaging is proposed. The pseudoscopic problem and matching of lens array in pickup and display are fundamental problems for real-time broadcasting based on integral imaging. We propose the reconstruction method of real 3D object and computational reacquisition method without matching of pickup and display lens array. In reconstruction, the real 3D object is reconstructed with volumetric information using depth extraction and triangular mesh, which can be rotated and translated in orthoscopic geometry. In reacquisition, the virtual lens array can generate the elemental image without matching of pickup lens array using OpenGL.

Presented herein is a novel stereoscopic three-dimensional (3D) display system with active color filter glasses. This system provides full-color 3D images by applying the time-multiplexing technique on the original anaglyph method. By switching between the opposite anaglyph statuses, a full-color anaglyph is presented. A liquid crystal panel from a 3D monitor serves as an active color filter operating at 120 Hz. A display panel and a color filter are connected to one graphic card as a dual-link system, for synchronization. To test the quality of this system, a left/right-eye image separation test and an experiment with stereoscopic images were carried out. Although there was some crosstalk and blur, the system, as expected, provided full-color 3D display. This system overcomes a monochromatic 3D image, which is the major weakness of the original anaglyph system.

In three-dimensional (3D) display based on lenticular lens method, the focal mode in which the gap between lens and display panel is almost equal to the focal length is widely used nowadays. However, because each pixel of the display panel has a finite size, reconstructed 3D image is displayed in virtual mode instead of focal mode. Because the elemental image which is a source of reconstructed image was generated for focal mode, the 3D image could suffer from image distortion. In this paper, view image error analysis based on autostereoscopic lenticular lens method and integral imaging method is presented based on numerical analysis and simulation results.

An optical depth converter that uses a lens array pair is analyzed theoretically and experimentally. We present a theory of depth conversion and explain the effects of the system parameters in the optical depth converter by using wave-optical analysis. Ray-optical analysis is applied to the investigation of the tendencies of the system parameter effects. We also show that the optical depth converter can be used for the three-dimensional screen in projection-type integral imaging systems.

A depth-enhanced three-dimensional–two-dimensional convertible display that uses a polymer-dispersed liquid crystal based on the principle of integral imaging is proposed. In the proposed method, a lens array is located behind a transmission-type display panel to form an array of point-light sources, and a polymer-dispersed liquid crystal is electrically controlled to pass or to scatter light coming from these point-light sources. Therefore, three-dimensional–two-dimensional conversion is accomplished electrically without any mechanical movement. Moreover, the nonimaging structure of the proposed method increases the expressible depth range considerably. We explain the method of operation and present experimental results.

A depth-enhanced three-dimensional-two-dimensional convertible display that uses a polymer-dispersed liquid crystal based on the principle of integral imaging is proposed. In the proposed method, a lens array is located behind a transmission-type display panel to form an array of point-light sources, and a polymer-dispersed liquid crystal is electrically controlled to pass or to scatter light coming from these point-light sources. Therefore, three-dimensional-two-dimensional conversion is accomplished electrically without any mechanical movement. Moreover, the nonimaging structure of the proposed method increases the expressible depth range considerably. We explain the method of operation and present experimental results.

The image depth of integral imaging is enhanced by doubling the number of central depth planes by use of optical path control. To accomplish this, the optical path lengths are changed by controlling whether reflections occur behind the lens array. We propose three schemes that use mirrors, a combination of beam splitters and polarizers, and polarization beam splitters, respectively. In experiments we implement the systems that are completely electronically controllable, are compact, and provide two central depth planes with 50.4-mm separation.

We propose a novel scheme to provide a two-dimensional/three-dimensional convertible feature for integral imaging operation under real/virtual mode. With a new fabrication method for a concave (or convex) half mirror array, a prototype system was implemented to verify the feasibility of our proposed scheme. Experimental results show that the proposed scheme also provides a wider viewing angle of an integrated image than the conventional integral imaging system. It is expected that the proposed two-dimensional/three-dimensional convertible integral imaging scheme will be useful for providing an integrated image with high resolution and a wide viewing angle.

We introduce a phase-only hologram generation method based on an integral imaging, and propose an enhancement method in representable depth interval. The computational integral imaging reconstruction method is modified based on optical °ow to obtain depth-slice images for the focused objects only. A phase-only hologram for multiple plane images is generated using the iterative Fresnel transform algorithm. In addition, a division method in hologram plane is proposed for enhancement in the representable minimum depth interval.