摘要:
A method for determining recording laser power on a super-resolution optical recording medium, on which information is recorded on a super-resolution optical recording medium by irradiating a laser beam modulated into a recording pulse train according to recording data to thereby form a recording mark train including recording marks and spaces smaller than the resolution limit of a reproduction optical system and recording marks and spaces equal to or larger than the resolution limit, is provided. At the time of recording, the method determines a minimum value and a maximum value of recordable laser powers determined by test-writing before recording, and determines a maximum value of a recordable range of laser power by adding to the minimum value one-third of a difference between the maximum value of the recordable laser powers and the minimum value. The method determines an optimal range of recording laser power from the minimum value of recordable laser powers to the maximum value of the recordable range.
摘要:
An information readout method for an optical information medium comprising an information recording layer having pits or recorded marks representative of information data involves the step of irradiating a laser beam to the information recording layer through an objective lens for providing readings of the pits or recorded marks. When the laser beam has a wavelength λ of 400 to 410 nm, the objective lens has a numerical aperture NA of 0.70 to 0.85, and the pits or recorded marks have a minimum size PL of up to 0.36λ/NA, readout is carried out at a power Pr of at least 0.4 mW for the laser beam. When the laser beam has a wavelength λ of 630 to 670 nm, the objective lens has a numerical aperture NA of 0.60 to 0.65, and the pits or recorded marks have a minimum size PL of up to 0.36λ/NA, readout is carried out at a power Pr of at least 1.0 mW for the laser beam. Pits or recorded marks of a size approximate to the resolution limit determined by diffraction can be read out at a high C/N.
摘要:
A method and apparatus for measuring the read stability of an optical disc are provided. Specifically, readout of the optical disc is repeated at each of at least two read laser beams powers being different from each other. A graph is drawn in which the inverses of the read powers are plotted on a horizontal axis and in which on a vertical axis is plotted the logarithm of a repeated readout number for each of the read powers. Here, the repeated readout number is the number of repetitions of the readout when a characteristic value for the number of repetitions of the readout varies and reaches a predetermined value. The read stability of the optical disc is evaluated by using the gradient of the graph.
摘要:
When a recording mark and a space, each having a size depending on a modulation code corresponding to information to be recorded, are formed in a super-resolution optical recording medium which has at least a substrate and a recording layer, a super-resolution layer, and a light transmitting layer on the substrate, a space shorter than at least the resolution limit of a reproducing optical system is formed so that the space has a crescent shape when plan view from top surface and a convex section when viewed in a direction normal to a track, thereby allowing high carrier-to-noise ratio (CNR) recording of information.
摘要:
It is an object of the present invention to provide an optical recording disc which can record data constituted by a recording mark train including recording marks and blank regions neighboring recording marks therein and reproduce the data therefrom even in the case where the lengths of a recording mark and a blank region between neighboring recording marks are shorter than the resolution limit, thereby markedly increasing the storage capacity thereof and can improve a C/N ratio of a reproduced signal and the reproduction durability thereof. An optical recording disc includes a substrate 2, a reflective layer 3, a third dielectric layer 4, a light absorption layer 5, a second dielectric layer 6, a decomposition reaction layer 7 containing platinum oxide as a primary component, a first dielectric layer 8 and a light transmission layer 9 and is constituted so that when the optical recording disc is irradiated with a laser beam 20 from the side of the light transmission layer 9, the platinum oxide contained in the decomposition reaction layer 7 as a primary component is decomposed into platinum and oxygen so that a bubble pit is formed in the decomposition reaction layer 7 by thus generated oxygen gas and fine particles of the noble metal penetrate into the bubble pit, thereby forming a recording mark in the decomposition reaction layer 7.
摘要:
An optical recording medium 10 is provided with a supporting substrate 11 and a light-transmitting layer 12, and further has between the light-transmitting layer 12 and the supporting substrate 11 a dielectric layer 31, a noble-metal oxide layer 23, a dielectric layer 32, a light absorption layer 22 and a dielectric layer 33. The second dielectric layer 32 contains as a main component ZnS or a mixture of ZnS and SiO2, and therein the proportion of ZnS to the sum of ZnS and SiO2 is set at a value from 60 mole % to 100 mole %. Since the material of the second dielectric layer 32 has both high hardness and elasticity, and high thermal conductivity besides, excellent balance of thermal conductivity with layer hardness can be achieved and makes it possible to form fine recording marks in true shapes.
摘要:
It is an object of the present invention to provide an optical recording disc which can record data constituted by a recording mark train including recording marks and blank regions neighboring recording marks therein and reproduce the data therefrom even in the case where the lengths of a recording mark and a blank region between neighboring recording marks are shorter than the resolution limit, thereby markedly increasing the storage capacity thereof and can improve the C/N ratio of the reproduced signal. An optical recording disc includes a substrate 2, a third dielectric layer 3, a light absorption layer 4, a second dielectric layer 5, a decomposition reaction layer 6 containing platinum oxide as a primary component, a first dielectric layer 7 and a light transmission layer 8 and wherein the decomposition reaction layer 6 has a thickness of 2 nm to 20 nm and the optical recoding disc is constituted so that when it is irradiated with a laser beam 20 from the side of the light transmission layer 8, the platinum oxide contained in the decomposition reaction layer 6 as a primary component is decomposed into platinum and oxygen so that a bubble pit is formed in the decomposition reaction layer 6 by thus generated oxygen gas and fine particles of the noble metal precipitate into the bubble pit, thereby forming a recording mark in the decomposition reaction layer 6.
摘要:
An optical recording device 10 of the present invention has a support substrate 11; an optical transmitting layer 12; and a first dielectric layer 31, a noble metal oxide layer 23, a second dielectric layer 32, a light absorption layer 22, a third dielectric layer 33, and a reflection layer 21, all of which are interposed, in this sequence from the optical transmitting layer, between the optical transmitting layer and the support substrate. The thickness of the support substrate 11 ranges from 0.6 mm to 2.0 mm; the thickness of the optical transmitting layer ranges from 10 μm to 200 μm; the thickness of the noble metal oxide layer ranges from 2 nm to 50 nm; the thickness of the second dielectric layer ranges from 5 nm to 100 nm; the thickness of the light absorption layer 22 ranges from 5 nm to 100 nm; and the thickness of the third dielectric layer 33 ranges from 10 nm to 140 nm. A superior characteristic can be acquired through super-resolution recording and super-resolution reproduction using an optical system for use with an optically recording medium of the next generation type.
摘要:
In an optical information medium having an information bearing surface having projections and depressions and/or capable of forming recorded marks, a functional layer is added. The information borne on the information bearing surface can be read by using reading light of a wavelength longer than 4NA·PL wherein PL is the minimum size of the projections and depressions or the recorded marks and NA is the numerical aperture of a reading optical system, setting the power of the reading light within such a range that the functional layer does not change its complex index of refraction, and irradiating the reading light to the information bearing surface constructed by the functional layer or to the information bearing surface through the functional layer or to the functional layer through the information bearing surface. The medium enables reading at a high resolution beyond the diffraction limit.
摘要翻译:在具有具有凹凸和/或能够形成记录标记的信息承载面的光信息介质中,添加功能层。 可以通过使用长于4NA的波长的读取光读取承载在信息承载表面上的信息。其中P L L是最小尺寸的凹凸 或记录标记,NA是读取光学系统的数值孔径,将读取光的功率设定在功能层不改变其复杂折射率的范围内,并将读取光照射到信息承载面 通过功能层或信息承载表面通过功能层或通过信息承载表面到功能层构成。 该介质能够以超过衍射极限的高分辨率进行读取。
摘要:
A method for reproducing data according to the present invention is adapted for reproducing data recorded in an optical recording disc including a multi-layered body formed by forming a decomposition reaction layer containing noble metal oxide as a primary component and a light absorption layer so as to sandwich a dielectric layer therebetween by irradiating a laser beam onto the optical recording disc and forming a recording mark train including at least one of a recording mark having a length shorter than a resolution limit and a blank region having a length shorter than the resolution limit therein, and is constituted by changing the read power Pr of the laser beam in accordance with a readout linear velocity at which data are to be reproduced from the optical recording disc. According to the thus constituted method for reproducing data, even in the case where the length of a recording mark or the length of a blank region between neighboring recording marks is shorter than the resolution limit, it is possible to record and reproduce a recording mark train including these recording marks and the blank regions. Therefore, this method can be applied to an optical recording medium whose storage capacity is markedly increased.