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3D simulation of triode electron gun is performed with regards its structure of multiple-tip field emission cathode. The table of geometrical parameters of electron gun is defined (dg-a/Da=1.5–4.0; dg-a/dg-c=10−4-10−2) as well as the optimal potentials of grid with large scale holes where the electrical field is uniform. Thus the effect of electron lens of grid comes to a minimum and laminar electron...
In this paper, a CMOS biologically expansion/contraction motion sensor and its implementation on z-motion direction/velocity detection is newly proposed. The proposed method to calculate the z-motion velocity is based on the principle of biconvex lens geometry (BLG). The proposed chip is attractive due to the fact that analog processing circuits and light sensor are integrated robustly and compactly...
Direction of Arrival (DOA) estimation algorithms specifically Multiple SIgnal Classification (MUSIC) and Minimum Variance Distortionless Response (MVDR) are used in a planar array - shaped dielectric lens combination to locate a desired user. However, refractive effect of the lens has to be compensated for in these algorithms, rapidly in real time to extract the true arrival angles. Geometrical optics...
We propose fan-in/out for multi-core fiber using GRIN lens and microlens array. The dimensions are ф8 × 40 mm. The insertion loss and crosstalk less than 1.0 dB and −49 dB were achieved, respectively.
We demonstrate ideal waveguide lenses with very large number of waveguides and with complete power concentration in a single waveguide. We also show for the first time an ideal waveguide lens structure.
Two photons in an entangled, spatially correlated (anti-correlated) state transmitted through an Anderson disordered lattice maintain their correlation (anti-correlation) but exhibit coincidence-map speckle in the Fourier plane.
We present a method to convert a digital single-lens-reflex (DSLR) camera into a high resolution consumer depth and light field camera by affixing an external aperture mask to the main lens. Compared to the existing consumer depth and light field cameras, our camera is easy to construct with minimal additional costs and our design is camera and lens agnostic. The main advantage of our design is the...
We propose a handheld light field camera for integral imaging with pixel mapping algorithm to generate an elemental image. We implement the light field camera which includes image sensor, imaging lens, and micro lens array. An elemental image can be generated by pixel mapping algorithm from captured image taken by light field camera. Experimental setup and resultant images are presented to verify...
In this paper, we present a table-top 3D display using integral floating technology to make a static-type display system. Because the proposed system does not use rotating devices, it has several advantages over conventional integral floating displays such as stability and static feature. We analyze the viewing characteristics and pickup process of the proposed system by ray optics and make an experimental...
Holoscopic 3D imaging also known as Integral imaging is an attractive technique for creating full color 3D optical models that exist in space independently of the viewer. The constructed 3D scene exhibits continuous parallax throughout the viewing zone. In order to achieve depth control, robust and real-time, a single aperture holoscopic 3D imaging camera is used for recording holoscopic 3D image...
Autostereoscopic 3D Display is robustly developed and available in the market for both home and professional users. However 3D resolution with acceptable 3D image quality remains a great challenge. This paper proposes a novel pixel mapping method for refining dark areas between two pinholes by distributing it into 3 times smaller dark areas and creating micro-pinholes in parallax barriers based holoscopic...
We characterize InGaAs Schottky barrier diodes (SBDs) with a variation in the anode size. High-efficiency terahertz (THz) pulse detection of the InGaAs SBDs is performed in the cases of anode diameters of 2 µm and 3 µm. The uniformity of the fabricated 1 × 20 InGaAs SBD array is measured to be fine. The THz imaging results using the 1 × 20 InGaAs SBD array are presented.
Lumped Element Kinetic Inductance Detectors (LEKID), when coupled with a silicon lens, have very high absorption efficiencies (70%) over more than one octave frequency band. In this contribution we introduce a theoretical derivation of the power received by these detectors by modeling them as an infinite array of dipoles. The theoretical model has been validated by measurements on a prototype working...
Micro lens array whose parameters directly affect the wave front detection performance is a core component of Hartmann-Shack wave front sensor. Make a deep theoretical study on sensitivity, spatial resolution, wave front measurement error and Dynamic Range which affect the design of the wave front detector, and research the coupling relationship between micro lens array parameters and focal length...
We present a depth estimation method for light field cameras by making use of Epipolar Plane Image (EPI) representations of the microlens sub images. Light field raw image structure has several sub images and generally depth is estimated using multi baseline techniques or object labeling schemes. Both these approaches are quite complex. EPI representation of the sub images when applied to the multi-baseline...
The dome antenna (DA) theory and principles are reviewed. The quasioptimal dome lens (DL) generating line is found as the approximation of the optimal generating line by a circular arc. The method of phase delay distribution calculation is described for a DA with a circular arc generating line of the DL while the feeding array is displaced along the system axis. The technique of feeding array phase...
National Institute of Information and Communications Technology (NICT) is conducting ultra-realistic communication research since 2006. The aim of this research is to create a sense of “being there” for natural and realistic communication. In this research project, NICT has developed some novel glasses-free 3D display systems. Among these systems, a large-size glasses-free 3D display using projector...
We report a simple algorithm for transforming the set of elemental images captured with an integral-photography set up, into the set of micro-images ready to be projected into an integral-imaging monitor. The method is based in the transposing relation between an integral photography and a plenoptic picture The reported technique permits to adapt the integral images to the resolution and size of the...
The super-multiview condition in the stereo hologram display is analyzed. The viewing zone of the display consists of viewing regions. Each of these regions can project images of having 1 pixel disparity difference with those of its immediate neighbors and its width can be smaller than the viewers' pupil size when the sizes of pixels in each pixel cell becomes smaller than 10 μm. Hence each of these...
The depth of field (DoF) in photography is limited by the aperture size and focal length. When the focal length is definite, large aperture size leads to small DoF. In dark scene, we use a large aperture at the cost of deep DoF. The paper gives a detailed analysis of the focused plenoptic camera mode presented by Georgiev and Lumsdaine, and proposes a novel reconstruction algorithm. It recovers the...
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