Abstract: Provided are apparatuses and methods using an optical speckle. An apparatus may include a light source configured to emit coherent light to an object and an imaging device configured to photograph a speckle pattern generated on the object by the coherent light. The apparatus may also include a processor having a function of determining whether the object is a living body or a non-living body by measuring a contrast of the speckle pattern. The processor may be configured to determine whether the object is a living body or not by comparing the contrast of the speckle pattern with a threshold contrast or a reference contrast previously registered by a user. The apparatus may be used by being applied to a fingerprint recognition system.

Abstract: An apparatus configured to control a heat flow is provided. The apparatus may include a semiconductor device region formed in a matrix; a heat rectifier region formed adjacent to the semiconductor device region; and a heat flow blocker formed in at least one region contacting the semiconductor device region and the heat rectifier region.

Abstract: Provided are a laser speckle contrast imaging method, a laser speckle contrast imaging system, and an apparatus which includes the laser speckle contrast imaging system. The laser speckle contrast imaging system includes a laser light source configured to irradiate laser beams toward a subject, the laser beams having a plurality of wavelength bands and different surface transmittances with respect to the subject. An imaging unit is configured to acquire speckle images by capturing images of speckles by using an image sensor, the speckles being formed when the irradiated laser beams are scattered from the subject. A signal processor is configured to convert the acquired speckle images into speckle contrast images and to acquire a compensated speckle contrast image by compensating for a change caused by a movement of the subject.

Abstract: An apparatus configured to control a heat flow is provided. The apparatus may include a semiconductor device region formed in a matrix; a heat rectifier region formed adjacent to the semiconductor device region; and a heat flow blocker formed in at least one region contacting the semiconductor device region and the heat rectifier region.

Abstract: A display device convertible between two-dimensional (2D) and three-dimensional (3D) is provided. The convertible display device is based on integral imaging (II) or integral photography (IP) and displays 2D or 3D images. An image processor generates and transmits elemental images to reconstruct a 3D image or transmits a desired two-dimensional image, and a transmission-type display device displays the image received from the image processor. At this time, a diffusion rate (or haze rate) of light illuminated from a point light source array that is made of a plurality of point light sources is controlled by a variable diffuser and as the light illuminates the transmission-type display device, the device displays 2D or 3D images. According to the present invention, a point light source array is generated by controlling a variable diffuser and as a result a display device convertible between 3D and 2D is achieved.

Abstract: The present invention provides a reflection-type three-dimensional display system. The present invention comprises an image providing device that provides elemental images; an image displaying device that displays the elemental images; a projective lens system that is located along the same axis as the image providing device; and a concave mirror array that is located along the same axis as the projective lens system. The projective lens system projects the image that is displayed by the image displaying device to the concave mirror array, and the concave mirror array reflects and integrates the projected image and therefore displays the three-dimensional image.

Abstract: The present invention provides a three-dimensional display system by using Integral Photography (TIP) technology. The present invention comprises an elemental lens switch located between a lens array and an image display for selectively opening and closing each elemental lens; an image processor for generating elemental images and synchronizing them with control signals of the elemental lens switch; an image display for displaying the elemental images; and a lens array comprising elemental lenses, for forming the three-dimensional image by refracting and integrating the elemental images displayed on the display. Hence, it is possible to display three-dimensional images with a wider viewing angle than that of the conventional IP method, because each elemental lens is synchronized with the corresponding elemental image and is switched properly.

Abstract: The present invention provides a reflection-type three-dimensional display system. The present invention comprises an image providing device that provides elemental images; an image displaying device that displays the elemental images; a projective lens system that is located along the same axis as the image providing device; and a concave mirror array that is located along the same axis as the projective lens system. The projective lens system projects the image that is displayed by the image displaying device to the concave mirror array, and the concave mirror array reflects and integrates the projected image and therefore displays the three-dimensional image.

Abstract: The present invention provides a three-dimensional display system by using Integral Photography (IP) technology. The present invention comprises an elemental lens switch located between a lens array and an image display for selectively opening and closing each elemental lens; an image processor for generating elemental images and synchronizing them with control signals of the elemental lens switch; an image display for displaying the elemental images; and a lens array comprising elemental lenses, for forming the three-dimensional image by refracting and integrating the elemental images displayed on the display. Hence, it is possible to display three-dimensional images with a wider viewing angle than that of the conventional IP method, because each elemental lens is synchronized with the corresponding elemental image and is switched properly.

Abstract: A volume holographic data storage(VHDS) system incorporates therein a tapered optical fiber for generating a speckle beam pattern from the tapered optical fiber for increasing the amount of holograms to be stored into a photorefractive crystal. The VHDS system includes a light source for generating a coherent light beam, a beam splitter for splitting the coherent light beam into a reference and a signal beams, a storage medium for storing the multiple holograms thereinto, a mirror for directing the signal beam to the storage medium, a coupler for coupling the reference beam to the tapered optical fiber, wherein one end of the tapered optical fiber has a tapered structure to give perturbation in the form of a speckle pattern to the reference beam from the tapered optical fiber and the reference beam containing the speckle pattern travels to the storage medium after being transmitted through the tapered structure, thereby the speckle pattern reference beam interfering with the signal beam in the storage medium.