摘要:
An optical information recording medium provided with an information layer comprising at least Te, O and M atoms (wherein the M is at least one element selected from a metallic element, a metalloid element or a semiconductor element, most preferably Pd). The information layer comprises the O atoms in 40 atom %-60 atom %, the M atoms in 2 atom %-25 atom % and the Te atoms in 15 atom %-58 atom %, thus obtaining a preferable recording property having a high C/N ratio and a small jitter in a wide power margin in recording and reproducing information having a small b/d ratio (a ratio of a recording bit length b for a spot diameter d).
摘要:
A method for manufacturing an optical information recording medium having an excellent mechanical strength, thermal stability, and improved overwrite cycle property can be provided by forming the dielectric layer by using a mixed target comprising ZnS and SiO.sub.2 in an atmosphere comprising rare gas and at least oxygen at the side where the dielectric layer does not contact to the recording layer. The optical information recording medium is manufactured by using the substrate, the recording layer comprising a material that varies reversibly between the optically identifiable states by an irradiation of a laser beam, and the dielectric layer at least one side of which has a two-layered structure at the upper and lower sides of the recording layer. At least one of the dielectric layers that does not contact to the recording layer is formed by using a mixed target comprising ZnS and SiO.sub.2 in a mixed atmosphere comprising rare gas and oxygen.
摘要:
The present invention relates to a production process and a production apparatus for the optical information recording media comprising a material thin film which exhibits a reversible change of the optical characteristics by the irradiation of an energy beam such as a laser beam on the substrate. By dropping the emission strength instantly to the virtual zero level after having the emission for a specified time in conducting the initial crystallization process, both a large irradiation power and a short irradiation time can be achieved to reduce the various thermal damages. The charging time can be shortened. In the production of optical information recording materials with single side structure, in particular, by applying an annealing process in combination with a formation process of the resin protection layer or a recording thin fil initialization process, the warp or distortion of media caused by the contraction of the ultraviolet ray curing resin layer or the recording thin film layer can be reduced or corrected to realize an optical information recording medium having excellent servo characteristics. Further, by having at least one of two media to be affixed with a transmissivity of an ultraviolet ray of 3% or more as a method to comprise an optical information recording medium with double sides structure not liable to have a warp or distortion, an ultraviolet ray curing resin can be used as an adhesive, resulting in simplifing the production process.
摘要:
On a substrate, a recording layer which reversibly transforms between two states with different optical properties--a crystalline phase and an amorphous phase--by the irradiation of a laser beam, a first and a second dielectric layer on the bottom and the top surfaces of the recording layer, and a third dielectric layer on one surface of the first or the second dielectric layers and on the opposite side with respect to the recording layer are successively laminated, thus preparing an optical information recording medium. The third dielectric layer has a smaller coefficient of thermal expansion than the first and the second dielectric layers, so that the thermal deformation of the first and the second dielectric layers is reduced and the mass transfer of the recording layer is controlled. As a result, the overwrite cycle characteristics of the optical information recording medium are excellent.
摘要:
An optical recording medium according to the present invention includes a substrate, and a recording film formed on the substrate, when receiving a laser beam for recording, the recording film taking either a first structural state or a second structural state according to the intensity of the laser beam; when receiving a laser beam for reproducing, the recording film partially changing the optical phase of the laser beam for reproducing according to the structural state, thereby changing the intensity of the laser beam for reproducing, wherein the optical absorbance of the recording film in the first structural state is substantially equal to that of the recording film in the second structural state, and the refractive index of the recording film in the first structural state is substantially different from that of the recording film in the second structural state.
摘要:
In a phase change optical disk wherein a first heat-resistant protection layer, an optical active layer showing a reversible phase change between a crystal state and an amorphous state, and a second heat-resistant protection layer are laminated on a substrate in this order, both of the first and the second heat-resistant protection layers are made of a mixture of a chalcogenide and a vitrification accelerating material. Further, a mixture ratio of the vitrification accelerating material in the second heat-resistant protection layer is larger than that in the first heat-resistant protection layer. Thereby, it becomes possible that the first heat-resistant protection layer has the mixing ratio which gives the refractive index value bringing suitable optical properties, while the second heat-resistant protection layer has the different mixing ratio which gives the thermal conductivity bringing suitable thermal properties. As a result, a phase change optical disk having high sensitivity, improved life characteristics in repeated record/erasure operations and wide production margin is provided.
摘要:
The apparatus includes optical recording media each of which includes a single plate substrate with recording layers and spiral grooves formed on both sides of the substrate and which are available for recording and reproduction or for recording, erasing and reproduction via irradiation with laser beams. Both surfaces of the recording media are available for simultaneous access, and a plurality of thin floating-type optical heads are provided to irradiate laser beams onto the recording media. The optical heads are respectively provided at each side of the recording media and float, responsive to rotation of the recording media, above the respective surfaces of the recording media at a distance of at most hundreds of microns. The combination of these optical recording media and optical heads makes it possible to stack plural pairs thereof within an ultra-thin space, thus greatly improving the on-line capacity of the optical recording apparatus.
摘要:
The method of determining the last sector containing recorded information or the last recorded sector, of a writer-once and read-many optical disc, comprises dividing tracks of a write-once and read-many optical disc into a plurality of sectors, where each sector has a data part for recording data and a sector ID part in which ID information for identifying the sector is recorded in advance. The ID information of a sector is attached to the data part of the sector and is recorded in the data part of the sector. The ID information reproduced from the data part of the sector is then compared with the ID information reproduced from the sector ID part of the sector, and when the ID information from the ID part and the data part coincide, the sector is determined to be the last recorded sector.
摘要:
A method for performing a high quality recording of information signals on an optical disk utilizes reversible structural changes between crystalline and amorphous states of a chalcogenide glass film or the like and two circular or nearly circular laser spots closely arranged along a recording track of optical disk. The preceding spot, which emits a continuous mode or high-frequency mode by far exceeding the recording frequency, operates cancel the past history in the irradiated portion by melting the recording film. The succeeding spot, which is modulated between the power levels for amorphizing and crystallizing according to the recorded information, operates to record new information signals on the track just after erased by the preceding laser spot.