Abstract: There is provided an optical information detecting method. The method includes: detecting an image of a source data page coded with balanced codewords by the use of 1:N (where N is greater than 1) excessive detection pixels; determining a distribution pattern of valid detection pixels and invalid detection pixels to be corrected in the detected image by the use of a light intensity distribution of the detected image; and dividing the detected image into balanced codeword detecting areas corresponding to the balanced codewords and sampling data of the balanced codeword detecting areas by the use of the determined distribution pattern and an optical distribution characteristic of the balanced codewords. Accordingly, it is possible to efficiently detect optical information by the use of a 1:N over-sampling method. Specifically, the distribution pattern of valid detection pixels and invalid detection pixels in the detected image of a data page can be properly used to sample a balanced code.

Abstract: Provided are optical information processing apparatus and method. In the optical information processing apparatus and method, when the recording regions in which optical information is recorded in an angular multiplexing scheme overlap with each other, a recording angle and a recording position for optical information is adjusted so as to improve reproducing efficiency of readout beams reproduced from the overlap recording regions, so that heights of “null” for diffraction energy reproduced from the recording regions and overlap recording regions can be lowered. Accordingly, it is possible to reduce crosstalk noise during the recording and producing of the optical information and to improve optical information recording quality and reproducing efficiency.

Abstract: An optical information reproducing apparatus using holography is provided. The holographic optical information reproducing apparatus includes an objective lens irradiating a reference beam to a predetermined position on a recording medium and receiving a reproducing beam reproduced from the recording medium, an optical information detector detecting the reproducing beam passing through the objective lens, a driving unit changing a distance between the optical information detector and the objective lens and an image adjusting unit adjusting magnification and a focus between an output image resulting from the reproducing beam passing through the objective lens and a detected image detected by the optical information detector with a variation in distance between the optical information detector and the objective lens.

Abstract: An optical information processing apparatus is provided. The optical information processing apparatus includes: an optical system which irradiates a reference beam on an optical information recording medium having a plurality of recording regions adjacent to each other so that the reference beam is wider than each of the recording regions; a filter which filters readout beams reproduced from the optical information recording medium to pass a selected readout beam reproduced from a selected recording region and separates neighborhood readout beams reproduced from neighborhood of the selected recording regions; a readout beam detector which detects the selected readout beam passing through the filter; a neighborhood readout beam detector which detects the neighborhood readout beams separated by the filter; and a controller which compares the neighborhood readout beams detected by the neighborhood readout beam detector to control a reproduction condition of the selected readout beam.

Abstract: An optical information reproducing apparatus and an optical information reproducing method using the same are provided. The optical information reproducing apparatus includes: a light source; a beam splitter which splits a beam emitted from the light source into a reference beam and a temporary beam; a temporary beam splitter which splits the temporary beam into a pair of assistant beams; an incident optical system which inputs the reference beam and the assistant beams to a recording medium in which optical information is recorded; a reproduction beam detector which detects reproduction beams reproduced in response to the reference beam, sets the position of the reproduction beam having the largest light intensity as a reference position, and sets a signal region on the basis of the reference beam; and an assistant beam detector which compares the light intensity of the assistant beams incident on the signal region with each other and sets an incident angle of the reference beam.

Abstract: A method of decoding a received signal encoded with an LDPC code is provided. The method comprises initializing bits with an initial value of the received signal, obtaining posterior values of the bits by iteratively decoding the bits in a row direction and a column direction, determining on the basis of the posterior values whether an iterative decoding operation should be performed and comparing the posterior values with predetermined values and updating the initial value of the bits, when it is determined that the iterative decoding operation is be performed.

Abstract: A wet type air cleaner includes a housing accommodating therein water; a blower having a fan for downwardly transferring air, installed above the water in the housing; an outer guide portion for transferring the air downwardly transferred by the blower into the water, connected to the blower as a unit; a driving unit for rotating the blower and the outer guide portion as a unit; and a plurality of discharge holes formed on a circumferential bottom surface of the outer guide portion. The air downwardly transferred by the blower is dispersed into the water in the housing through the discharge holes.

Abstract: An optical system capable of selectively processing CD, DVD and holographic digital data is provided. The system includes a beam generation unit providing a linearly polarized light beam; a beam splitter for respectively reflecting and transmitting a first and a second linearly polarized light beam component; an optical sensor; a first beam path through which the first linearly polarized light beam component propagates to serve as a reference beam for the holographic digital data; and a second beam path for accepting the second linearly polarized light beam component, the second light beam component serving as a beam source for reproducing the CD and DVD digital data, wherein a beam carrying digital data reproduced from any one of CD, DVD and holographic storage medium propagates along the second beam path and is reflected by the beam splitter toward the optical sensor.

Abstract: An apparatus for compressing holographic data includes an image capture device for capturing an image of an interference pattern reconstructed by irradiating a reference beam and converting the image into m bits. In such an apparatus, a splitter removes least significant j bits from the m-bit data and divides m?j bits of the m-bit data into most significant k bits and remaining m?j?k bits. Thereafter, a compressor converts the most significant k bits into l bits, which is combined with the m?j?k bits to output n bits, wherein l<k and n=l+m?j?k. In this way, by compressing a certain number of most significant bits of the m-bit data and thus relatively increasing the number of the remaining least significant bits of the m-bit data, the BER of final reconstructed image data can be improved.

Abstract: An optical information reproducing apparatus and an optical information reproducing method using the same are provided. The optical information reproducing apparatus includes: a reference beam providing unit which inputs a reference beam to a reproduction recording area to be reproduced and a peripheral recording area around the reproduction recording area on an optical information recording medium, a peripheral beam detecting unit which transmits a reproduction beam reproduced from the reproduction recording area in response to the reference beam and detects a peripheral beam reproduced from the peripheral recording area, a tracking servo unit which analyzes optical information of the detected peripheral beam and controls a tracking position, and a reproduction beam detecting unit which detects the reproduction beam having pass through the peripheral beam detecting unit.

Abstract: A holographic ROM system of the present invention includes a lens unit for filtering and collimating an output radiation diffracted from a holographic disk in order to produce an output data beam. The lens unit includes an objective lens for collimating the output radiation and a filtering film for filtering the output radiation. The objective lens and the filtering film are formed in a single body.

Abstract: In order to pick up a digital storage medium including a holographic storage medium and a reflective storage medium, a first and a second beam each of which has a different wavelength are used and a reflected beam and a reconstructed signal beam are propagated through a propagation path, wherein the first beam is reflected by the digital storage medium to generate the reflected beam and the second beam is diffracted by a holographic interference pattern in the holographic storage medium to generate the reconstructed signal beam. A polarizing beam splitter is used to split the reflected beam from the propagation path while a laser line mirror is used to separate the reconstructed signal beam from the propagation path.

Abstract: A block coding algorithm uses an original block group having n+1 original blocks of m-bit message, which a first original block of m-bit message is encoded as a reference block of n-bit codeword and n original blocks of m-bit message placed after the first original block of m-bit message are encoded as n weighted blocks of n-bit codeword, based on a bit sequence of the reference block. A block decoding algorithm decodes n weighted blocks to generate corresponding original blocks of m-bit message and reconstructs the first original block of m-bit message from a sequence of reference bits, wherein each reference bit implies whether each of n weighted blocks is an A type weighted block or a B type weighted block.

Abstract: A holographic memory system includes a light source for generating a reference beam having a wavelength; and a photodetecting device for selectively detecting a reconstructed signal beam corresponding to the reference beam. The photodetecting device includes a band-pass filter for transmitting light of a wavelength band including the wavelength of the reconstructed signal beam while blocking light having a wavelength deviating from the wavelength band; and a photodetecting unit for detecting the light transmitted through the band-pass filter.

Abstract: In an apparatus for detecting holographic data reproduced from a holographic medium, the holographic medium has an interference pattern and the holographic data is reproduced when a first portion of a reference beam is diffracted by the interference pattern within the holographic medium. A transmission beam detector detects a light intensity of a transmission beam which is a second portion of the reference beam, wherein the transmission beam is not diffracted to reproduce the holographic data and passes through the holographic medium. Then, a CCD (charge coupled device) controller generates a driving signal in accordance with the detected light intensity. Thereafter, a CCD detects the holographic data in response to the driving signal.

Abstract: In a holographic digital data storage system, a light source generates a reference beam, a holographic optical element saves a plurality of interference patterns between the reference beam and a plurality of beams of specific sizes and a beam splitter splits each reproduced beam into a holographic signal beam and a holographic reference beam. A medium records an interference pattern between the holographic reference beam and the holographic signal beam and reflecting the holographic reference beam to generate a reflective information beam and, if only the holographic reference beam is illuminated, a displaying means displays a holographic reproduced beam for the holographic signal beam and detecting the reflective information beam.

Abstract: A holographic apparatus includes a mask for modulating a signal beam to generate a modulated signal beam; a conical prism, which has a cone portion and a base portion, for refracting a reference beam to generate a refracted reference beam, wherein the refracted reference beam interferes with the modulated signal beam in a holographic medium to thereby record data thereon, the base portion facing the holographic medium. The holographic apparatus can be miniaturized by a positional relationship between the conical prism and the holographic medium.

Abstract: Disclosed is a capacitor for effectively shielding noise generated from a magnetron. According to an embodiment of the present invention, a case of the capacitor is combined with a ground plate in order that electrode insulation pipes integrally formed in the case extend through extending pipes mounted in the ground plate. Electrodes respectively extend through the electrode insulation pipes. A fixing cover is inserted through an upper opening of the case into the case to be disposed over the electrode insulation pipes, of which a fixing pipe extends through the case so as to come in contact with a screwed hole formed in the ground plate. The extending pipes respectively prevent unnecessary microwave noise generated from the magnetron. A length of the extending pipe is preferably in a range of 5 to 15 mm. Furthermore, the extending pipe and the electrode are made such that a sum of radiuses of the extending pipe and the electrode is less than 5 mm.

Abstract: A refrigerator cabinet assembly is disclosed. The refrigerator cabinet assembly has an outer case including two laterally spaced side walls and a top wall interconnecting the two side walls. Each of the side walls and the top wall is provided with front face portions and rear face portions. The structural rigidity of the outer case is increased by a plurality of reinforcing members. The reinforcing members are secured to the outer case by, e.g., self-drilling screws. The refrigerator cabinet assembly is devoid of welded portions.

Abstract: A method for padding interlaced texture information on a reference VOP to perform a motion estimation detects whether said each texture macroblock of the reference VOP is a boundary block or not. After the undefined texture pixels of the boundary block are extrapolated from the defined texture pixels thereof by using a horizontal repetitive padding, a transparent row padding and a transparent field padding sequentially, an undefined adjacent block is expanded based on the extrapolated boundary block.