Naoya Takeya

Bio: Naoya Takeya is an academic researcher from Japanese Ministry of International Trade and Industry. The author has contributed to research in topics: Liquid-crystal display & Pattern recognition (psychology). The author has an hindex of 3, co-authored 5 publications receiving 109 citations.

Holographic Generation of Contour Map of Diffusely Reflecting Surface by Using Immersion Method

Abstract: This paper describes the double exposure holographic formation of a contour map over a diffusely reflecting or transmitting of arbitrary shape and surface finish by using an immersion method with media of different indices of refraction between successive exposure. A wavelength λ effectively contributing to the fringe contour is given by λ0/Δn where λ0 is the wavelength of the laser and Δn is the index variation. Index variations were introduced by pressure difference in Freon to give λ=600 µ and 200 µ, and by the combination of two liquids to give 14 µ and 25 µ, thus extending the change of height corresponding to each fringe contour continuously up to one thousand times greater than with the optical Fizeau fringes. A correcting plate of a Schmidt camera in the grinding process was used as a test object and its figuring error were analyzed.

Mesure de la Déformation d'un Objet par Interférométrie Holographique

Abstract: Les franges de l'interferometrie holographique sont etudiees pour les mouvements types d'un objet, et la forme et la localisation des franges sont obtenues. Il resulte de ces etudes que le faisceau d'eclairage de l'objet est parallele a la direction d'observation et que la separation des franges d'egale inclinaison de celles d'egale epaisseur permet de mesurer le deplacement global et la deformation pure longitudinale et laterale.

Correlation Techniques by Holography and its Application to Fingerprint Identification

Abstract: The optical correlation technique is a powerful means for optical pattern recognition [1][2], and holography brings a new and precise method known as optical matched filtering [3] using a Fourier-transform hologram.

Mri tomographic image stereoscopic vision device

Abstract: PURPOSE:To stereoscopically observe an MRI tomographic image in all cross sections being parallel to each other by allowing it to have width on one straight line in the vertical front of a hologram screen by execution reproduction of a virtual image simultaneously with all liquid crystal displays, or dispersing it within a range of the time of an afterimage. CONSTITUTION:An MRI tomographic image stereoscopic vision device 1 is provided with a frame memory 2, an image display device 3 and a hologram screen 4. The frame memory 2 brings three-dimensional information in plural cross sections alpha1-alphan (n=12 and an equal interval of an interval delta) being parallel to each other of an organization 9 in a living body obtained by an MRI device 8, to three-dimensional high speed image processing by a computer 5, and thereafter, can store (n) pieces of two-dimensional images I1-In constituted by a personal computer 6. The image display device 3 is provided with (n) pieces of liquid crystal displays 7 (LC1-LCn). Each liquid crystal display is connected to the frame memory 2, and the liquid crystal displays LC1, LC2, LC3...LCn can image I1, I2, I3...In independently from each other and by keeping pace with each other.

Basics of Holography

Abstract: Basics of Holography is a general introduction to the subject written by a leading worker in the field It begins with the theory of holographic imaging, the characteristics of the reconstructed image, and the various types of holograms Practical aspects of holography are then described, including light sources, the characteristics of recording media and recording materials, as well as methods for producing different types of holograms and computer-generated holograms Finally, important applications of holography are discussed, such as high-resolution imaging, holographic optical elements, information processing, and holographic interferometry The book includes comprehensive reference sections and appendices summarizing some useful mathematical results Numerical problems with their solutions are provided at the ends of chapters This is an invaluable resource for advanced undergraduate and graduate students as well as researchers in science and engineering who would like to learn more about holography and its applications in science and industry

Time-lapse interferometry and contouring using television systems.

Abstract: A novel approach to time-lapse interferometry and contouring is introduced that uses television rather than photographic techniques. A first interferogram is stored on a video storage device such as a magnetic disk. After a change in the stress of the object, a second interferogram is electronically compared to the stored pattern to form a signal representative of the fringe pattern caused by the deformation. This signal may be directly displayed on a cathode-ray tube or employed by some automatic inspection device.

3-D volume visualization display

Abstract: A volumetric multi-layer screen including a plurality of electrically switchable layers that are stacked and coextensive, each of the plurality of electrically switchable layers including: a first transparent dielectric substrate having a first side and a second side; a first transparent electrode coated on the first side of the first transparent substrate; and an electrically switchable polymer dispersed liquid-crystal film coated on the first transparent electrode. The electrically switchable polymer dispersed liquid-crystal film includes a) a host polymer having an index of refraction and b) a nematic liquid crystal having i) an ordinary index of refraction that substantially matches the index of refraction of the host polymer when an electric field is applied across the electrically switchable polymer dispersed liquid-crystal film from the first transparent electrode, and ii) an extraordinary index of refraction that causes visible light to be scattered at a host polymer/nematic liquid crystal interface when the electric field is not applied across the electrically switchable polymer dispersed liquid-crystal film by the first transparent electrode.

Multi-planar volumetric display system and method of operation

Abstract: A multi-planar volumetric display system and method of operation generate volumetric three-dimensional images using a multi-surface optical device including a plurality of individual optical elements arranged in an array; an image projector for selectively projecting images on respective optical elements to generate a first volumetric three-dimensional image viewable in the multi-surface optical device; and a floating-image generator for projecting the first volumetric three-dimensional image to generate a second volumetric three-dimensional image viewable as floating in space at a location separate from the multi-surface optical device. The optical elements includes liquid crystal elements having a controllable variable translucency. An optical element controller controls the translucency of the liquid crystal elements, such that a single liquid crystal element is controlled to have an opaque light-scattering state to receive and display an image from the image projector; and the remaining liquid crystal elements are transparent to allow the viewing of the displayed image on the opaque liquid crystal element. The image projector projects the images into the multi-surface optical device to generate the entire first volumetric three-dimensional image at a rate greater than 35 Hz to prevent human-perceivable image flicker, so the image projector projects the images onto a respective optical element at a rate of at least 2 kHz. The image projector may include adaptive optics for rapidly focusing the images, or a plurality of laser light sources for projecting red, green, and blue laser light to generate and project the images in a plurality of colors.