Abstract: The invention relates to a method for setting an optimum value of a write parameter for use in an optical recording apparatus for writing information on an optical recording medium by means of a radiation beam. The optimum value of a write parameter is found by curve-fitting a function and obtaining a characteristic write power level (PChar) from the curve-fitting function. It is then assessed if the characteristic write power level (PChar) qualify as an optimum value of a write parameter. If the characteristic write power level (Pchar) does not qualify as an optimum value of a write parameter then an iteration procedure is started, where the subsequent initial values of write power level (Pini, n), are given by Pini, n+1=A Pini, n+(1?A)Pchar, n, where A is a constant, and n is an integer. The invention also relates to an optical recording apparatus and an optical recording medium according to the invention.

Abstract: A signal current wiring line is configured to carry a signal current from a first circuit block to a second circuit block. A return current wiring line is configured to carry a return current from the second circuit block to the first circuit block. The signal current wiring line and the return current wiring line are stacked with an offset in the width direction so as to form a region between the surface of the casing on the second wiring line side and the signal current wiring line where the signal current wiring line faces the surface of the casing on the second wiring line side without the return current wiring line intervening between them.

Abstract: In an exemplary embodiment of the present invention, after test write is performed with a predetermined test power to a first track on an optical disk, test write is performed with the same test power as the first track to a second track adjacent to the first track. Then, reproduction signals are obtained by reproducing the first track and the second track respectively, and a determination whether or not the test power is set to a recording laser power in recording main information is made based on a relationship between the obtained reproduction signals.

Abstract: Disclosed herein is a laser driving device including: a sample-hold section; a first pulse generating section; a second pulse generating section; a light emission waveform generating section; a storing section; and a sampling pulse generating section.

Abstract: An optical disc device is provided with an optical head (1) including a light source (21), a condensing optical system including an objective lens (28) for receiving a light beam emitted from the light source and forming a microspot on a multilayer optical recording medium, a photodetector (201) for receiving the light beam reflected by the multilayer optical recording medium and outputting an electrical signal corresponding to the amount of light and a coma aberration correcting element (26) for correcting a coma aberration of the condensing optical system, and a processing circuit (3) for controlling the condensing optical system and the coma aberration correcting element.

Abstract: A laser driving device includes: a first pulse generating section; a second pulse generating section; a light emission waveform generating section; and a light emission level pattern storing section.

Abstract: An optical data recording medium, in which irradiation of a light beam is used for recording and/or reproducing data includes (i) a substrate having an a rise and/or a recess which are a light-incident surface, (ii) a reflective layer, provided on the light-incident surface of the substrate, for reflecting the light beam, (iii) a light absorption layer for converting, to heat, a light of the light beam to heat on the surface of the reflective layer, (iv) a reproducing layer, provided on the surface of the heat-light converting layer, having a transmittance that changes in accordance with a light intensity distribution of the light beam. The optical data recording medium is excellent in super-resolution property, and enables reproduction of a shorter mark length.

Abstract: This invention allows super-resolution reproduction with which a better bER value is attainable, when information is recorded by a random pattern including a mark length not longer than a resolution limit, by use of a highly versatile signal decoding method. Information is recorded as marks and spaces coded by RLL(1,7) modulation, which each of the marks and spaces have one of, a plurality of lengths, and 2T marks and 2T spaces of the marks and spaces being formed are shorter than 0.12 ?m. An information recording layer (20) includes a reproduction film (21) and a reflective film (22) which are provided in this order from a side from which reproducing light is incident, which reproduction film is made of (i) zinc oxide, (ii) strontium titanate, (iii) titanium oxide, (iv) cerium oxide, or (v) a material including at least one of the (i) through (iv), and which reflective film is made of tantalum or titanium.

Abstract: This invention allows super-resolution reproduction with which a better bER value is attainable, when information is recorded by a random pattern including a mark length not longer than a resolution limit, by use of a highly versatile signal decoding method. Information is recorded as marks and spaces coded by RLL(1,7) modulation, which each of the marks and spaces have one of a plurality of lengths, and 2T marks and 2T spaces of the marks and spaces being formed are shorter than 0.12 ?m. An information recording layer (20) includes a reproduction film (21) and a reflective film (22) which are provided in this order from a side from which reproducing light is incident, which reproduction film is made of (i) zinc oxide, (ii) strontium titanate, (iii) titanium oxide, (iv) cerium oxide, or (v) a material including at least one of the (i) through (iv), and which reflective film is made of tantalum or titanium.

Abstract: This invention allows super-resolution reproduction with which a better bER value is attainable, when information is recorded by a random pattern including a mark length not longer than a resolution limit, by use of a highly versatile signal decoding method. Information is recorded as marks and spaces coded by RLL(1,7) modulation, which each of the marks and spaces have one of a plurality of lengths, and 2T marks and 2T spaces of the marks and spaces being formed are shorter than 0.12 ?m. An information recording layer (20) includes a reproduction film (21) and a reflective film (22) which are provided in this order from a side from which reproducing light is incident, which reproduction film is made of (i) zinc oxide, (ii) strontium titanate, (iii) titanium oxide, (iv) cerium oxide, or (v) a material including at least one of the (i) through (iv), and which reflective film is made of tantalum or titanium.

Abstract: This invention allows super-resolution reproduction with which a better bER value is attainable, when information is recorded by a random pattern including a mark length not longer than a resolution limit, by use of a highly versatile signal decoding method. Information is recorded as marks and spaces coded by RLL(1,7) modulation, which each of the marks and spaces have one of a plurality of lengths, and 2T marks and 2T spaces of the marks and spaces being formed are shorter than 0.12 ?m. An information recording layer (20) includes a reproduction film (21) and a reflective film (22) which are provided in this order from a side from which reproducing light is incident, which reproduction film is made of (i) zinc oxide, (ii) strontium titanate, (iii) titanium oxide, (iv) cerium oxide, or (v) a material including at least one of the (i) through (iv), and which reflective film is made of tantalum or titanium.

Abstract: Provided are a method and apparatus for adjusting brightness of an illumination device that is used in photographing an analysis object in a bio disk. The method includes taking images of an analysis object in a bio disk; calculating brightness of the images of the analyzing object; and adjusting brightness of an illumination device which is used in the photographing operation of the analysis object in the bio disk based on a difference between the calculated brightness and a target brightness.

Abstract: An image forming apparatus is provided. An exposure component is equipped with a plurality of light emitting elements arrayed along a first direction. An output component is equipped with output ends corresponding to each of the light emitting elements and the output component, when correcting an amount of misalignment in the first direction, outputs drive signals of one line corresponding to a line on a most upstream side of drive signals of plural lines from the output ends that have been shifted by a number corresponding to the amount of misalignment in the first direction. A plurality of connecting wires interconnect each of the output ends and each of the light emitting elements. A judging component is connected to each of the connecting wires, and judges whether or not the drive signals are being normally transmitted through the connecting wire that the judging component has selected.

Abstract: According to one embodiment, an information recording medium has a plurality of recording layers, and records and reproduces information by using a semiconductor layer of 450 nm or less. When reproducing information, letting x be the frequency of repetitive recording of a shortest mark length and shortest space length of the information, the ratio of the value of a highest level to the value of a level at x/190 of a sum signal detected within the frequency range of x/3240 to x/190 is lower than 32 dB, or the ratio of the average value of the amplitudes of signals of repetitive recording of the shortest mark length and shortest space length to the value of the highest level within the frequency range of x/3240 to x/190 is higher than 10 dB.

Abstract: To provide a squarylium compound forming a metal complex, expressed by the general formula (I): where R1 and R2 are the same or different and each of R1 and R2 represents a substituted or unsubstituted alkyl, aralkyl, aryl, or heterocyclic group; Q represents a metal atom having coordinating ability; q represents 2 or 3; R3 represents a substituted or unsubstituted aralkyl, or aryl group; R4 represents a substituted or unsubstituted alkyl, aralkyl, or aryl group,’ R5 represents a hydrogen atom, or substituted or unsubstituted alkyl, aralkyl, or aryl group; R6 represents a halogen atom, nitro group, cyano group, or substituted or unsubstituted alkyl, aralkyl, aryl, or alkoxy group; p represents any integer ranging from 0 to 4; and RGs are the same or different and any adjacently located two R6s optionally form a substituted or unsubstituted aromatic ring together with two adjacent carbon atoms when p is 2, 3 or 4.

Abstract: According to the present invention, multiple space bitmaps (SBMs #0 and #1 30) are provided for the user data area of each recording layer. A disc management structure update unit including one of those space bitmaps and a disc definition structure (TDDS 32) and having a size of one block is written on a management information area (TDMA 17). As a result, data including the disc definition structure (TDDS 32) can always be arranged in the first block at the top of the management information area (TDMA 17).

Abstract: To record information as an array of optically changed portions arranged along a track in an optical storage medium, a pulsed laser beam is emitted toward the optical storage medium while causing at least one of the optical storage medium and the pulsed laser beam to be moved relative to each other. A plurality of pulses of the pulsed laser beam are emitted during a time span in which one segment of the track having a length corresponding to a length of one optically changed portion is scanned with the pulsed laser beam. An intensity of light with which a segment of the track is to be illuminated to form each individual optically changed portion is adjusted by causing a shutter to selectively reduce the number of pulses of the pulsed laser beam with which the segment of the track is to be illuminated.

Abstract: An optical data retrieval system configured to retrieve data from a data storage medium, including: a source of n path-entangled photons, where n is an integer of at least 2; a detector system configured to determine if n photons have been received; and a mechanism to direct photons from the source to the data storage medium and to the detector system.

Abstract: An object of the present invention is to provide an optical information recording medium suited for high-density and high-speed recording using a recording wavelength of 360 to 450 nm, in particular, around 400 nm (for example, 405 nm) and its recording method. The present invention is based not on a conventional High to Low method but on a Low to High method and, when the reflectance of the pit is higher than that of the non-pit area, the maximum film thickness of the recording layer at the track area where the pits are arranged is in the range from 25 to 60 nm and the maximum film thickness of the recording layer at the area adjacent to the track area is in the range of 5 to 30 nm, a satisfactory push-pull signal can be obtained. Further, the film thickness of the reflecting layer is preferably set in the range from 120 to 180 nm, and groove width of the reflection layer is preferably set in the range from 85 to 150 nm.

Abstract: A recording method which optically records two-dimensional data including a positioning mark and data area in a recording medium. In this method, the state of the positioning mark is changed from a first state to at least one second state different from the first state every given number of recording times of such two-dimensional data.

Abstract: In a multilayer disc has an increased number of recording layers) spaced by spacing from each other, a generation interval between focus error (FE) signals detected from the respective recording layers becomes small. This causes mutual interference between the FE signals and a resulting undesired offset and the like in the signals, leading to a significantly deteriorated quality of the FE signals. To avoid this, in an optical pickup device according to the present invention, detection surfaces are newly added at positions adjacent to the FE signal detection surfaces, a predetermined detection signal obtained from the newly-added detection surfaces is multiplied by a predetermined coefficient value depending on the spacing between the recording layers, and the multiplied signal is subtracted from the original FE signal. As a result, mutual interference between the FE signals can be remarkably reduced.

Abstract: The information recording medium (100) of the present invention includes: an information layer (110) including a recording layer (115) capable of changing its phase containing at least one selected from Ge—Te, Sb—Te and Ge—Sb, and two or more dielectric layers (117, 118) disposed on the optical beam incident side with respect to the recording layer (115); and a transparent layer (102) disposed on the optical beam incident side with respect to the information layer (110) adjacent to the information layer, made of a transparent material with respect to the optical beam, and having a refractive index n of 1.75 or more.

Abstract: Provided is an optical information reproducing medium for realizing an excellent super resolution reproduction while performing a high-speed reproduction. The optical information recording medium includes a plurality of super resolution layers (13, 15) whose refractive index or attenuation coefficient changes nonlinearly at predetermined temperatures individually corresponding thereto. Individually on at least two of the super resolution layers (13, 15), the light amounts of the laser beams to be irradiated for causing temperatures of the recording medium to reach the predetermined temperatures are different. The recorded information of the optical information recording medium is reproduced by the areas, in which at least one of the plurality of the super resolution layers has changed in optical characteristic nonlinearly whereas at least one of the remaining layers has not changed in optical characteristic nonlinearly is formed as an aperture.

Abstract: A first light source 1a emits a first light flux with a first wavelength. A second light source 1b emits a second light flux with a second wavelength that is different from the first wavelength and a third light flux with a third wavelength that is different from the first wavelength and the second wavelength. A collimator lens 6, a first objective lens 9, and a second objective lens 10 collect the first to third light fluxes as converged light on an optical disc. A first composite photodetector 13 detects the reflected light fluxes from the optical disc. The first composite photodetector 13 includes a first quartered light-receiving unit 13a that receives a light flux obtained by reflection of at least one light flux from among the first to third light fluxes from the optical disc and a second quartered light-receiving unit 13b that receives a light flux obtained by reflection of the remaining light fluxes from the optical disc.

Abstract: To provide an optical recording medium of which mechanical properties and storage stability will not be impaired, and which will show little deterioration in signal properties even after being left to stand at high temperature under high humidity. An optical recording medium to perform recording/reading by means of blue laser, which has a value of 10 or less as obtained by “error rate after its environmental resistance test/error rate before its environmental resistance test” in error rates obtained before and after its environmental resistance test carried out by leaving the medium to stand for 500 hours at a temperature of 80° C. under a relative humidity of 80%.

Abstract: This invention provides a surface plasmon polariton direction change device (1) for changing a propagation direction of a surface plasmon polariton (5). The surface plasmon polariton direction change device (1) includes a metal film support member (2), and a first metal film (3) and a second metal film (4) which are provided on a predetermined surface of the metal film support member (2), are provided adjacently to each other, and are different from each other in effective refractive index.

Abstract: To provide an optical pickup and an optical information device, capable of obtaining excellent signal characteristics for an optical disk on and/or from which recording and/or reproducing are performed using a laser. The optical pickup includes an optical detector, a support holder for holding the optical detector, and an optical base for fixing the support holder. The support holder has at least two notches at its both ends, the optical base has convex portions corresponding to the notches of the support holder, the optical base and the support holder are fixed by photo-curable adhesives for bonding the convex portions and the support holder to each other, and the shortest distance between the side faces of the convex portions, which do not face each other, is equal to or less than the width of the support holder in the direction of right and left ends.

Abstract: An optical head includes: a slider which moves relative to a recording medium while the slider is floating above the recording medium; an optical waveguide which is provided on a side surface of an end portion of the slider and which has the focusing function of forming a light spot on the recording medium; and a light guide optical system that guides a light pencil to the optical waveguide. A light pencil coupling portion which receives the light pencil from the light guide optical system is provided in a surface parallel to a direction in which the light pencil is guided by the optical waveguide; and a reflective surface which deflects the light pencil to the light pencil coupling portion is provided in the light guide optical system. The light pencil coupling portion has the function of correcting aberration resulting from oblique incidence of the light pencil obliquely incident from the light guide optical system.

Abstract: A data storage apparatus and method. The apparatus comprises a mounting structure, a motor mechanically attached to mounting structure, and a data storage platter mechanically attached to the motor. The apparatus additionally comprises a single actuator arm comprising a first and second read/write data head or multiple radial movement mechanisms each comprising a read/write data head. The single actuator arm is configured to move axially along an arc and across a top surface of the data storage platter such that the first read/write data head has access to a first section and a second section of the data storage platter and the second read/write data head only has access to the second section of data storage platter. Each radial movement mechanism moves a different read/write data head radially all along a radius of the data storage platter and over and across different sections of the data storage platter.

Abstract: The present invention provides a recording/reproducing device which shortens time required for dubbing, when a user performs the dubbing of program data. The recording/reproducing device of the present invention is a recording/reproducing device which records and reproduces information, including: a tuner control unit 4 which obtains first information; a recording/reproduction control unit 13 which records, in an HDD 15, the first information obtained by the tuner control unit 4, and records, in an optical disc held in the optical disc drive 14, second information which is information having the same content as the first information; a CPU 5 which invalidates the second information; and a user input control unit 9 which receives an instruction requesting the first information recorded in the HDD 15 to be recorded in the optical disc. In the case where the user input control unit 9 receives the instruction, the CPU 5 validates the invalidated second information.

Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the first light reflecting layer is smaller than the thickness of the second light reflecting layer.

Abstract: In a multilayer optical disc having information layers conforming to a plurality of different optical disc standards, because the type of each information layer is not recorded in the other information layers, in read and write operations by a compatible optical disc device conforming to a plurality of optical disc standards, every time the information layer being accessed changes, it has been necessary to read the type of the information layer and select a method of generating a tracking error signal adapted to the type of information layer, so access has taken time. In order to solve the above problem, in the optical multilayer disc according to the present invention, having information layers conforming to a plurality of different optical disc standards, in an area in one of the information layers, information about the other information layers is recorded. The time required to access the other information layers can be reduced by using this information to select a tracking error signal generating method.

Abstract: An optical read/write apparatus causes a read/write light beam from illuminating means to strike only one side of an optical storage medium including stacked data storage layers each of which is readable/writeable separately from the other layers. In this case, the optical read/write apparatus operates so that data is read/written from/into a second data storage layer after fully recording a recordable area of a first data storage layer. Thus, light can be shone with uniform intensity across the substantially entire recordable area of the second data storage layer without using a complex read/write system even under such conditions that the transmittance to light of the first data storage layer in the recordable area may vary depending on whether any data is recorded in the recordable area.

Abstract: There is provided an optical disc recording/reproducing apparatus which can reduce the chip size using the high-miniaturization process and can enhance the detection accuracy. A signal which is obtained by amplitude-adjusting a header region in a reproduced signal detected by an optical pickup (1) is digitized, and peak detection or bottom detection from the reproduced signal in each of a first section and a second section in the header region is performed by detection circuits (9) to (12), respectively. Then, amplitude data in the first section and the second section are obtained by subtracters (13) and (14) from the detected values in the respective detection circuits. A difference in amplitude between the first section and the second section in the header region is obtained by a subtracter (15) based on the amplitude data, and the amplitude difference is outputted as an off-track error signal.

Abstract: Optical data storage media containing a “dark” layer structure are disclosed. Layered metals and metal oxides provide a dark background that enhances detection of changes in the data layer of the storage media. Combinations such as chromium metal and chromium oxide, and molybdenum metal and molybdenum oxide are offered as examples of suitable materials.

Abstract: Method and apparatus for formatting a data storage medium, such as a magnetic or optical disc. In accordance with various embodiments, a data storage medium is rotated while a write beam is used to write data to the rotating medium. The data are written in the form of a plurality of concentric data tracks. A deflection angle of the write beam is continuously adjusted in an axial direction along each track. In some embodiments, the axial deflection of the write beam imparts a desired angular offset between a beginning point of a first track and a beginning point of an immediately adjacent second track. This allows a first translation geometry, such as a linear translation path of a linear actuator, to emulate a different second translation geometry, such as a rotary translation path of a rotary actuator.

Abstract: An optical pickup is disposed which irradiates a laser beam onto an optical disc where a guide groove having characteristics of thermal interference (heat discoloration) is spirally formed. The optical pickup irradiates the laser beam along the guide groove to conduct one of data recording in which pits indicating a data length are formed, and visible-image formation in which a part of the optical disc is discolored. The laser beam irradiation position is controlled so that the data recording is conducted with starting from the inner peripheral side of the optical disc, and the visible-image formation is conducted with starting from the outer peripheral side of the optical disc.

Abstract: A disk recording/reproducing apparatus includes a disk rotator which rotates an optical disk, an optical pickup, a slide motor which moves the optical pickup into a radial direction of the optical disk, and a controller which controls at least the disk rotator and the slide motor in accordance with a signal obtained from the optical pickup. The controller determines an alternation destination for recording data at an alternation origin therein or during the alternation process depending on a position of the alternation origin on the optical disk and a reference position on the optical disk, when the optical disk has an alternation area on an innermost periphery and an outermost periphery, and the recording/reproducing apparatus conducts the alternation process upon detection of a defect block within a user data recording area on the optical disk, thereby conducting the alternation process thereon.

Abstract: A high data density optical recording medium, a method and an apparatus for reading from such an optical recording medium, and a method for mastering such an optical recording medium are proposed. For achieving a high data density the optical recording medium has marks that have a tip and are covered by a material that generates a detectable effect under the influence of high electric fields.

Abstract: A recording parameter setting device includes a trial recording parameter setting section (23) and a reproduced signal quality judging section (26). The trial recording parameter setting section (23) inquires, in accordance with the recording information, a storage section (3) containing recording parameters used for controlling heat of recording marks, and sets a trial recording parameter, wherein (a) the recording parameters are used for controlling heat of at least rear edges, (b) the recording parameters are classified in accordance with recording mark lengths, and (c) recording parameters of a predetermined recording mark length or longer are classified into a same group. The reproduced signal quality judging section (26) judges whether or not a reproduced signal obtained by reproduction of the trial recording carried out in accordance with the trial recording parameter satisfies a predetermined reproduced signal quality.

Abstract: An optical disc apparatus comprising: a spindle motor configured to drive a turntable on which an optical disc is loaded to rotate; a first substrate on which a first support member rotatably supporting a rotation shaft of the spindle motor is fixed, and on which a second support member is formed at a position adjacent to the spindle motor; a second substrate; an optical pickup device; and a guide member configured to guide the optical pickup device in a radial direction of the optical disc loaded on the turntable, one end of the guide member being supported by the second support member on the first substrate and fixed to a fixing member on the second substrate, and the other end of the guide member being fixed to the fixing member on the second substrate.

Abstract: The present invention makes it possible to use an optical pickup in common with conventional optical disks. In a three-dimensional mark recording layer (111v) of a voluminal medium (100v), information is recorded by forming a three-dimensional record mark (RM) in the vicinity of the focus (Fb) of a blue light beam (Lb) according to the blue light beam (Lb) that is concentrated and has a light intensity equal to or larger than a predetermined intensity. The information is reproduced from the three-dimensional mark recording layer (111v) on the basis of a reproducing blue light beam (Lbr) deriving from irradiation of the blue light beam (Lb). A servo layer (114v) of the voluminal medium (100v) reflects at least part of the red light beam (Lr) which is irradiated in order to square the position of the blue light beam (Lb) in the three-dimensional mark recording layer (111v) with an arbitrary target mark position and whose wavelength is different from that of the blue light beam (Lb).

Abstract: A recording medium (100) is provided with: an element layer including a semiconductor element (110) and an emission element (130), which emits light on the basis of an instruction from the semiconductor element; and a recording layer (120) in which readable predetermined data is recorded by irradiating a light beam.

Abstract: An optical recording medium to be used for a retail activation solution is proposed. The optical recording medium is a modified ROM disk that can only be played after the application of an activation process. For this purpose at least a part of a reflective layer of a read-only area of the optical recording medium is replaced by a light sensitive layer stack that changes its reflectivity upon illumination. Also proposed are a method for producing such an optical recording medium as well as methods and apparatuses for initializing and/or activating such an optical recording medium.

Abstract: An HF waveform prevailing during a read operation varies due, for instance, to changes in the ambient temperature of an optical disc drive and variations in the characteristics of a laser. This degrades read performance and decreases the number of rewritable disc read operations. To address the above problems, an optical disc drive and an optical information read method are disclosed. The disclosed optical disc drive and optical information read method vary an HF amplitude in relation to the resistance, differential resistance, or temperature of the laser.

Abstract: An image forming apparatus at least includes a photoreceptor, a light emitter, a detector and a controller. The light emitter irradiates the photoreceptor with a laser beam so as to form an electrostatic latent image thereon. The detector detects an incident amount of the laser beam falling on a light receiving portion of the detector on a main scan line. The controller changes at least one of a detection sensitivity of the detector for a laser beam and an emission amount of the laser beam emitted from the light emitter when the incident amount of the laser beam detected by the detector is not greater than a predetermined value.

Abstract: Provided herein is an optical disc having: an optical plotting layer which is formed at a label surface side and on which an image is formed by heat change with a laser beam emitted from a recording surface side; a protective layer which is formed at the label surface side of the optical plotting layer, protects the optical plotting layer, and through which the image can be viewed from the label surface side; a reflective layer which is formed at the recording surface side of the optical plotting layer and reflects the laser beam; and a substrate which supports the reflective layer, the protective layer and the optical plotting layer.

Abstract: Provided herein is an optical disc having: an optical plotting layer 17 which is formed at a label surface B-side and on which an image is formed by heat change with a laser beam 28 emitted from a recording surface A-side; a protective layer 18 which is formed at the label surface B-side of the optical plotting layer 17, protects the optical plotting layer 17, and through which the image can be viewed from the label surface B-side; a substrate 15 which supports the protective layer 18 and the optical plotting layer 17; and a guide track 24 which is formed on the optical plotting layer 17 so as to be intermittent in a guide direction.

Abstract: A traverse for an optical disc drive comprising a base, a main shaft motor, a pick-up motor and a pick-up head module is provided. The base includes a bottom plate and a plurality of raised mesas. The bottom plate has an opening and the raised mesas connect with the bottom plate. The main shaft motor is disposed on the raised mesas. The pick-up motor is disposed on the bottom plate and the pick-up head module connects with the pick-up motor. The pick-up motor enables the pick-up head module to move inside the opening. Additionally, the present invention also provides an optical disc drive with the said traverse.

Abstract: A Viterbi detector includes an ACS circuit that performs addition of a path metric and branch metrics, comparison of the path metric values and path selection based on the result of comparison. The ACS circuit performs a path decision based on the path metric values and the reproduced signal supplied to the Viterbi detector at the time instant that is a specified number of channel clocks earlier during the path selection. The ACS circuit selects a mark-continuing path if the reproduced signal at the time instant that is the specified number of channel clocks earlier has an amplitude corresponding to any mark, and performs path decision based on the path metric values if the reproduced signal does not have the amplitude corresponding to any mark.