Abstract: An optical recording medium and an optical information device that improve the quality of a servo signal and a reproduction signal. In the optical recording medium, when shape-wise thicknesses tr1, tr2, tr3, and tr4 of a cover layer (42), a first intermediate layer (43), a second intermediate layer (44), and a third intermediate layer (45) are respectively converted into thicknesses t1, t2, t3, and t4 of the respective corresponding layers each having a predetermined refractive index “no”, a defocus amount with respect to a layer having a refractive index nr? and a thickness tr? (satisfying: 1???n (where ? is a positive integer and n is an integer of 4 or more)), and a defocus amount with respect to a layer having the refractive index “no” and a thickness t? (satisfying: 1???n (where ? is a positive integer and n is an integer of 4 or more)) are equal to each other.

Abstract: A method for inspecting an optical information storage medium includes irradiating the medium with a laser beam and rotating the medium by a constant linear velocity control technique by reference to the radial location at which the laser beam forms a spot on the medium; changing the rotational velocities according to the radial location on the medium between at least two linear velocities; generating a focus error signal and/or a tracking error signal based on the light reflected from the medium; performing a focus control and/or a tracking control on the laser beam based on the focus and/or tracking error signal(s); and passing the branched outputs of control loops for the focus and/or tracking error signal(s) through predetermined types of frequency band-elimination filters to obtain residual errors of the focus and/or tracking error signal(s) and comparing the residual errors to predetermined reference values.

Abstract: A method for inspecting an optical information storage medium includes irradiating the medium with a laser beam and rotating the medium by a constant linear velocity control technique by reference to the radial location at which the laser beam forms a spot on the medium; changing the rotational velocities according to the radial location on the medium between at least two linear velocities; generating a focus error signal and/or a tracking error signal based on the light reflected from the medium; performing a focus control and/or a tracking control on the laser beam based on the focus and/or tracking error signal(s); and passing the branched outputs of control loops for the focus and/or tracking error signal(s) through predetermined types of frequency band-elimination filters to obtain residual errors of the focus and/or tracking error signal(s) and comparing the residual errors to predetermined reference values.

Abstract: A method for inspecting an optical information storage medium includes irradiating the medium with a laser beam and rotating the medium by a constant linear velocity control technique by reference to the radial location at which the laser beam forms a spot on the medium; changing the rotational velocities according to the radial location on the medium between at least two linear velocities; generating a focus error signal and/or a tracking error signal based on the light reflected from the medium; performing a focus control and/or a tracking control on the laser beam based on the focus and/or tracking error signal(s); and passing the branched outputs of control loops for the focus and/or tracking error signal(s) through predetermined types of frequency band-elimination filters to obtain residual errors of the focus and/or tracking error signal(s) and comparing the residual errors to predetermined reference values.

Abstract: A calculation of a reliability value |Pa?Pb|?Pstd, representing represents a maximum likelihood decoding result on a portion which corresponds to a start or termination edge of a recording mark and has a high probability of error occurrence by a maximum likelihood decoding method, is performed on each combination of a predetermined mark length and a space length immediately before the mark and each combination of the mark length and a space length immediately after the mark. Based on the calculation result, a recording parameter is optimized, and recording reflecting the optimized recording parameter is performed.

Abstract: The present invention is to realize a proper inner zone layout in an optical disk having at least three layers. A test area is provided in the inner zone (inner circumference side area) in each of recording layers. The test areas of each layer are so disposed as to be prevented from overlapping with each other in the layer direction. Furthermore, the number of management information recording/reproduction areas overlapping with the test area in the layer direction at a position closer to the laser-incident surface than this test area is set equal to or smaller than one in each test area of each recording layer. The management information recording/reproduction areas are each so disposed as to be prevented from overlapping with the test areas in the respective recording layers in the layer direction on the disk substrate side of the test areas.

Abstract: An optical information medium measurement method of the present invention, for measuring a degree of modulation in an optical information medium of a multilayered structure having a plurality of information layers, includes a first step of measuring the modulation degree of each layer of the optical information medium, by use of a measurement optical system, a second step of obtaining a thickness between layers of the optical information medium, a third step of obtaining a reflectance of each layer of the optical information medium, and a fourth step of converting the modulation degree of each layer, the modulation degree being measured in the first step, into a modulation degree at a reference optical system differing from the measurement optical system, based on a value indicative of the thickness between layers, the thickness being obtained in the second step, and a value indicative of the reflectance of each layer, the reflectance being obtained in the third step.

Abstract: An object of the invention is to improve the quality of a servo signal and a reproduction signal. Shape-wise thicknesses tr1, tr2, . . . , and trN of a cover layer and first through (N?1)-th intermediate layers of an optical recording medium having refractive indexes nr1, nr2, . . . , and nrN are converted into thicknesses t1, t2, . . . , and tN of the respective layers having a predetermined refractive index “no” which makes a divergent amount equal to a divergent amount of a light beam resulting from the thicknesses tr1, tr2, . . . , and trN, a difference DFF between the sum of a thickness “ti” through a thickness “tj”, and the sum of a thickness “tk” through a thickness “tm” is set to 1 ?m or more (where i, j, k, and m are each any positive integer satisfying i?j<k?m?N), and the thicknesses t1, t2, . . . , and tN are calculated by products of a function f(n) expressed by the following formula (1), and the thicknesses tr1, tr2, . . . , and trN: f(n)=?1.088n3+6.1027n2?12.042n+9.

Abstract: A signal evaluation method according to the present invention is a method for evaluating a read signal, retrieved from an information recording medium, based on a binarized signal generated from the read signal by a PRML method.

Abstract: A recording power determination method for determining a recording power of an optical beam for recording data on an information storage medium includes the steps of recording test data on the information storage medium at a plurality of test recording powers; reading the test data recorded at each test recording power, generating a signal, and measuring a modulation factor of the signal corresponding to each test recording power; calculating a product of an n'th power of each test recording power and the corresponding modulation factor, thereby obtaining a plurality of products corresponding to the plurality of test recording powers, where n is a value of exponent and is a real number other than 1; calculating a first recording power based on the correlation between the plurality of test recording powers and the plurality of products; and calculating the recording power based on the first recording power.

Abstract: The present invention provides a measure for getting read/write control information stored within a space of a predetermined size in a format that ensures compatibility with media of a lower order or an older generation even if the size of the read/write control information increases significantly as the storage densities of information storage media rise in the near future. On an information storage medium, a data sequence is writable as a combination of marks and spaces. The medium has at least one information storage layer, which has an information storage area to store information and a control information area for use to perform a read/write operation on the at least one information storage layer. The control information area stores at least one set of control information, which includes a first kind of write pulse information including information to be used as a reference value and a second kind of write pulse information including information to be used as an offset value.

Abstract: An information recording medium according to the present invention includes three or more information recording layers. Each of the plurality of information recording layers includes a test recording area usable for adjusting a recording condition. One of the plurality of information recording layers includes a reproduction-only management data area in which management data usable for managing the information recording medium is pre-recorded. One information recording layer includes a recordable management data area in which management data usable for managing the information recording medium is newly writable. Each of the other two or more information recording layers among the plurality of information recording layers includes a test recording area at a radial position overlapping the radial position of a part of the reproduction-only management data area. In the one recording layer including the recordable management data area, the recordable management data area is provided at two positions, i.e.

Abstract: An object of the invention is to provide an optical recording medium and an optical information device that enable to improve the quality of a servo signal and a reproduction signal.

Abstract: An object of the invention is to provide an optical recording medium and an optical information device that enable to improve the quality of a servo signal and a reproduction signal.

Abstract: A specific recording pattern is sequentially written onto an optical disc using each of three sets of recording pulse conditions as trial writing. The recording patterns are reproduced sequentially. Edge shift amounts of a mark which corresponds to each of three sets of recording pulse conditions are measured from a reproduction signal. Compensation values for the recording pulse conditions are obtained from calculation by linear approximation based on the measured values.

Abstract: A recording/reproduction apparatus, comprising a first recording section for recording test information onto a medium using at least one recording power, a reproduction section for reproducing at least one test signal indicating the test information from the medium, and a second recording section for recording information onto the medium using one of the at least one recording power. The reproduction section comprises a decoding section for performing maximum likelihood decoding of the at least one test signal and generating at least one binary signal indicating a result of the maximum likelihood decoding, a calculation section for calculating a reliability of the result of the maximum likelihood decoding based on the at least one test signal and the at least one binary signal, and an adjustment section for adjusting a recording power for recording the information onto the medium to the one recording power based on the reliability.

Abstract: An optical information storage medium according to the present invention has at least one information storage layer. The optical information storage medium has a management area that stores at least one unit containing control information about the optical information storage medium. The control information includes a format number, which provides information about at least a write strategy type and a write pre-compensation type, and a write strategy parameter, which provides information about the magnitude of shift in an edge position, or variation in the pulse width, of a write pulse train to form a recording mark. And the value of the format number changes according to a combination of the write strategy type and the write pre-compensation type.

Abstract: An object of the invention is to improve the quality of a servo signal and a reproduction signal. Shape-wise thicknesses tr1, tr2, . . . , and trN of a cover layer and first through (N?1)-th intermediate layers of an optical recording medium having refractive indexes nr1, nr2, . . . , and nrN are converted into thicknesses t1, t2, . . . , and tN of the respective layers having a predetermined refractive index “no” which makes a divergent amount equal to a divergent amount of a light beam resulting from the thicknesses tr1, tr2, . . . , and trN, a difference DFF between the sum of a thickness “ti” through a thickness “tj”, and the sum of a thickness “tk” through a thickness “tm” is set to 1 ?m or more (where i, j, k, and m are each any positive integer satisfying i?j<k?m?N), and the thicknesses t1, t2, . . . , and tN are calculated by products of a function f(n) expressed by the following formula (1), and the thicknesses tr1, tr2, . . . , and trN: f(n)=?1.088n3+6.1027n2?12.042n+9.

Abstract: A recording power determination method for determining a recording power of an optical beam for recording data on an information storage medium includes the steps of recording test data on the information storage medium at a plurality of test recording powers; reading the test data recorded at each test recording power, generating a signal, and measuring a modulation factor of the signal corresponding to each test recording power; calculating a product of an n'th power of each test recording power and the corresponding modulation factor, thereby obtaining a plurality of products corresponding to the plurality of test recording powers, where n is a value of exponent and is a real number other than 1; calculating a first recording power based on the correlation between the plurality of test recording powers and the plurality of products; and calculating the recording power based on the first recording power.

Abstract: An information recording medium according to the present invention includes at least three information recording layers. If the readout power of a laser beam in reading information from an information recording layer L(n) is identified by Pw(n), and if the readout power of the laser beam in reading information from an information recording layer L(n+a) is identified by Pw(n+a), then a base thickness between the information recording layers is determined so that the intensity of the light when the information recording layer L(n+a) is irradiated with a laser beam having the readout power Pw(n) becomes equal to or lower than that of the light when the information recording layer L(n+a) is irradiated with a laser beam having the readout power Pw(n+a).