Abstract: An information recording and reproduction apparatus includes a recording section for recording data into a recording medium in accordance with address information recorded in the recording medium, a first reproduction section for reproducing at least one data including the data recorded in the recording medium in accordance with a first reproduction method to obtain at least one reproduced data, a second reproduction section for reproducing the address information in accordance with a second reproduction method to obtain reproduced address information, and a determination section for mapping the data to a specific reproduced data of the at least one reproduced data based on the address information and the reproduced address information, and comparing the data with the specific reproduced data to determine a recording condition of a region of the recording medium storing the data.

Abstract: An optical disc drive usable with discs to which data is continuously recorded and discs having a sector format can quickly resume playback signal output after passing imperfection causing potential reading errors, and plays disc with few read errors. A detection signal generator detects DC level fluctuation in the playback signal read from the disc and generates a detection signal tracking the DC level fluctuation. A selector selects a detection signal or a null signal without valid polarity based on the detection signal generated by the detection signal generator and input to the selector. A clamping unit performs a clamping process to suppress DC level fluctuation in the playback signal based on the detection signal when the selection unit selects the detection signal, and does not perform the clamping process when the selection unit selects the null signal. A signal processor performs specific signal processes based on clamping unit output.

Abstract: An optical disk storing write-once information usable for protecting the copyright of the software by preventing the duplication, unauthorized use, etc., of the software. In the optical disk, a recording layer (213) is formed on a disk substrate (211) with a dielectric layer (212) inbetween. Then, an intermediate dielectric layer (214) and a reflecting layer (215) are successively laminated upon the recording layer (213), and an overcoat layer (216) is formed on the surface of the reflecting layer (215). A plurality of BCA (one of write-once identification information systems) sections (220a and 220b) are recorded by lowering the vertical magnetic anisotropy of the recording layer (213). At the time of reproduction, the write-once information is detected from differential signals.

Abstract: A disk of the present invention includes a first storage area for reproducing data and a second storage area for recording and reproducing data, the number of sectors in each track in the first and second storage areas close to each other is larger in the first storage area than in the second storage area, and leading edges of sectors in each track in the first storage area are aligned in at least one line in a radius direction.

Abstract: An optical disk and a method for storing write-once information usable for preventing the illegal copies. The optical disk comprises a disk substrate, and a recording layer having a magnetic film disposed on the disk substrate. The optical disk stores write-once information formed by first recording areas and second recording areas and the write-once information being different for each disk. The second recording areas are formed as a plurality of stripe-shaped marks that are oblong in a radial direction of the disk by irradiating laser light based on a modulation signal of the write-once information in the pre-determined portion of the recording layer, in a manner that a magnetic anisotropy in a direction perpendicular to a surface of the second recording areas is smaller than a magnetic anisotropy in a direction perpendicular to a surface of the first recording areas.

Abstract: An asymmetry detection apparatus includes: a clock signal generator for generating a clock signal based on a reproduced signal; an A/D converter for sampling the reproduced signal in synchronization with the clock signal; a determiner for determining whether a level of each of a plurality of sampled data obtained by the sampling operation is equal to or greater than a predetermined level; and a detector for detecting asymmetry in the reproduced signal by using predetermined ones of the sampled data based on an output from the determiner.

Abstract: A disk of the present invention includes a first storage area for reproducing data and a second storage area for recording and reproducing data, the number of sectors in each track in the first and second storage areas close to each other is larger in the first storage area than in the second storage area, and leading edges of sectors in each track in the first storage area are aligned in at least one line in a radius direction.

Abstract: A first D/A converter having a fine frequency resolution and second D/A converter having a rough frequency resolution are used in combination for frequency control and phase control, and a wide operational frequency range in reproduction can be covered with high accuracy by incorporating a digital PLL circuit. The dynamic ranges of the first and second D/A converters are so controlled as to be subject to addition and subtraction at a time having no problem for data reproduction. Therefore, the frequency adjustment can be rapidly performed in the frequency control and the clock continuously locked to the data can be obtained by the phase control, thereby remarkably reducing the seek time.

Abstract: A two-layer optical disk has a first layer of a disk shaped recording medium for storing data and a second layer of a disk shaped recording medium placed over the first layer for storing data. Data blocks A, B, C are stored in the first layer in said order. Similarly, data blocks X, Y, Z are stored in the second layer in said order. When reading the data from the two-layer optical disk, the data blocks are read in the order of A, X, B, Y, C, Z.

Abstract: A two-layer optical disk has a first layer of a disk shaped recording medium for storing data and a second layer of a disk shaped recording medium placed over the first layer for storing data. Data blocks A, B, C are stored in the first layer in said order. Similarly, data blocks X, Y, Z are stored in the second layer in said order. When reading the data from the two-layer optical disk, the data blocks are read in the order of A, X, B, Y, C, Z.

Abstract: A document reading apparatus includes a reference member used for determining the reference gray scale of an image on a document; a fluorescent lamp for illuminating the reference member; an image sensor for receiving light from the fluorescent lamp via the reference member and for converting the received light into an electric signal; a circuit for obtaining the difference between the latest data corresponding to a specified pixel among the output of the image sensor and the data before a predetermined period corresponding to the specified pixel among the output of the image sensor; and a circuit for determining whether or not the read operation of the document should be started by comparing the difference and a predetermined value.

Abstract: A color image scanning apparatus is disclosed which includes: an image sensor for scanning an original, the image sensor including a plurality of line sensors arranged in a sub-scanning direction; a determination circuit for determining the traveling speed of the image sensor in the sub-scanning direction in accordance with a magnification ratio of the original; a driving circuit for moving the image sensor in the sub-scanning direction at the speed determined by the determination circuit; a correction circuit for correcting the output of the image sensor to simultaneously output signals corresponding to an identical position of the original; a filter for filtering the output of the correction circuit in accordance with the magnification ratio of the original and the speed determined by the determination circuit, wherein the determination circuit determines the speed so that each distance of the plurality of line sensors arranged in the sub-scanning direction is substantially equal to an integral multiple of

Abstract: A white balance coefficient setting unit 51 sets a white balance coefficient for an image signal; a white balance correction coefficient determination unit 52 determines two white balance correction coefficients to be applied to a luminance signal of the image signal in accordance with the white balance coefficient; a luminance signal operation unit 59 obtains two output signals by multiplying the luminance signal by each of the two white balance correction coefficients; a first adder 57 adds one of the two output signals and a first color difference signal of the image signal together; a second adder 58 adds the other output signal and a second color difference signal of the image signal together. Adding results of the first and the second adders 58 and 59 will be output as a white balance correction value to be applied to the two color difference signals.

Abstract: In a picture processing apparatus, respective results of subtraction calculation between the relevant pixel and the reference pixels are obtained by a subtraction arithmetic circuit. The resultant differences are converted nonlinearly by a nonlinear conversion circuit, and thereafter a summation calculation of these resultant differences are performed by a first addition arithmetic circuit. The obtained result is added to data of the relevant pixel by a second addition arithmetic circuit; thereby achieving MTF correction. By adequately selecting the input-output characteristic of the nonlinear conversion circuit, a stable contour line enhancement is achievable even when noise is present in the picture signal.

Abstract: A rigid-type multilayer printed wiring board is produced by bonding a multilayer printed wiring sheet substantially comprising a thin insulating resin layer (1), at least one metal foil printed wiring layer (8, 11) and a plurality of conductive holes (7) formed through the two layers onto a metal board (10) through an insulation laminate (9). In according this method, a multilayer printed wiring interlayer sheet consisting of the multilayer printed wiring sheet retaining a printed wiring pattern unprocessed metal foil (2b) on one surface thereof is prepared first. In this case, a given printed wiring has already been processed on the other surface and sometimes in the inner portion of the interlayer sheet. Then, the other surface of the interlayer sheet is bonded to the surface of the metal board through the insulation laminate. Thereafter, a desired printed wiring pattern is formed on the printed wiring pattern unprocessed metal foil (2b) on the one surface of the interlayer sheet.

Abstract: The front and rear surfaces of plates to be butt-welded are slidably held by front and rear backing shoes, respectively, for defining a welding space in a narrow groove formed by the edges of the plates, and the edges are melted by a plasma arc generating torch, while a plurality of consumable electrodes are fed into the welding space are molten by arcs generated therebetween. The backing shoes, the torch, and the consumable electrodes are moved along the groove to obtain a butt-weld of high quality at high efficiency. In addition, the electrode of the torch has an elongated configuration in section at its end portion, and its restraining nozzle surrounding the electrode has a nozzle opening which also has an elongated configuration in correspondence to the end portion of the electrode. The longitudinal axes of these configurations are aligned with each other to effectively utilize the energy of a plasma arc generated by the torch.

Abstract: Waste gas containing sulfur oxide (SO.sub.x) and nitrogen oxide (NO.sub.x) is mixed with an ozone-containing gas to have the value x of NO.sub.x fall in the range of 1.2 to 2.5 and thereafter brought into contact with an aqueous solution containing sulfuric acid, nitric acid and an iron compound to be deprived of SO.sub.x and NO.sub.x. To the solution with which the waste gas has been brought into contact, air or oxygen is added to effect oxidation of the part of said oxides still remaining therein in an unoxidized state and regenerate the activity of the iron compound functioning as a catalyst. Part of the solution to which the addition of air or oxygen has been made is recycled as the solution for the purpose of contact with waste gas.

Abstract: In a vertical position welding method and an apparatus for practicing the method, front and rear water-cooling type backing shoes are slidably positioned on the front and rear surfaces of metal plates to be butt-welded, respectively, so as to form a welding space in a groove formed by the adjacent edges of the metal plates. A consumable electrode is continuously fed into the welding space, while a plasma arc generating torch fixedly provided on the backing shoe in contact with the front surface of the work generates a plasma arc to melt the adjacent edges of the metal plates to be welded, and the backing shoes and the torch are moved upward at the same speed to move the welding space in response to the melting rates of the work and the consumable electrode, thus achieving the welding of the metal plate in vertical position. Furthermore, the torch is tilted to facilitate the melting of the metal plates.