This fiber scanning scope has the potential for pixel-accurate delivery of high quality laser radiation, allowing the future integration of imaging with diagnosis and therapy.

We applied a polarimetric analysis to retinal imaging, to examine the potential improvement in characterizing blood vessels. To minimize the reflection artifact of the superficial wall of the blood vessel, we computed depolarized light images by removing the polarization retaining light reaching the instrument. These depolarized light images were compared to images from the average of all the light. Michelson contrast was computed for the vessel profiles across arteries and veins, and was higher for the depolarized light images. Depolarized light images provide one step towards improving the characterization of retinal blood vessels.

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The novel frequency-multiplexed modulator architecture of the MIT Mark III holo-video display poses a significant challenge in generation of appropriate video signals. Unlike in our previous work, here it is necessary to generate a group of adjacent single-sideband RF signals; as this display is intended to be manufacturable at consumer-electronics prices we face the added requirement of compact and inexpensive electronics that are compatible with standard PC graphics processors. In this paper we review the goals and architecture of Mark III and then describe our experiments and results in the use of a hardware/software implementation of Weaver's single-sideband modulation method to upconvert six 200MHz baseband analog video signals to a set of RF signals covering a nearly contiguous 1GHz range. We show that our method allows efficient generation of non-overlapping signals without aggressive filtering.

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Image-based holographic stereogram rendering methods for holographic video have the attractive properties of moderate computational cost and correct handling of occlusions and translucent objects. These methods are also subject to the criticism that (like other stereograms) they do not present accommodation cues consistent with vergence cues and thus do not make use of one of the significant potential advantages of holographic displays. We present an algorithm for the Diffraction Specific Coherent Panoramagram --a multi-view holographic stereogram with correct accommodation cues, smooth motion parallax, and visually defined centers of parallax. The algorithm is designed to take advantage of parallel and vector processing in off-the-shelf graphics cards using OpenGL with Cg vertex and fragment shaders. We introduce wavefront elements -"wafels" -as a progression of picture element "pixels", directional element "direls", and holographic element "hogels". Wafel apertures emit controllable intensities of light in controllable directions with controllable centers of curvature, providing accommodation cues in addition to disparity and parallax cues. Based on simultaneously captured scene depth information, sets of directed variable wavefronts are created using nonlinear chirps, which allow coherent diffraction of the beam across multiple wafels. We describe an implementation of this algorithm using a commodity graphics card for interactive display on our Mark II holographic video display.

Here, we propose and demonstrate a modular holographic display system that allows seamless spatial tiling of multiple coarse integral holographic (CIH) displays called “holobricks”. A holobrick is a self-contained CIH module enclosing a spatial light modulator (SLM), a scanner, and periscopic coarse integral optics. Modular CIH uses a coarse pitch and small area but high-bandwidth SLM in conjunction with periscopic coarse integral optics to form the angularly tiled 3D holograms with large viewing areas and fields of view. The creation of periscopic coarse integral optics prevents the optical system from being larger than the holographic image and allows the holographic fringe pattern to fill the entire face of the holobrick. Thus, multiple holobricks can be seamlessly abutted to form a scalable spatially tiled holographic image display capable of both wide field-of-view angle and arbitrary large-size area. We demonstrate an initial prototype that seamlessly tiles two holobricks each with 1024 × 768 pixels, 40° FOV, full color, 24 fps, displaying 2D, 3D holographic stereograms, and full parallax 3D CGI Fresnel holograms.

Measurement of the light orbital angular momentum spectrum using an optical geometrictransformation Martin P J Lavery, Gregorius C G Berkhout, Johannes Courtial et al. Design challenges and guidelines for free-space optical communication links using orbital-angular-momentum multiplexing of multiple beams Alan E Willner, Guodong Xie, Long Li et al.