Abstract: The present invention is to provide a production method for an optical disc, capable of obtaining a good S/N ratio without deterioration of the stamper quality due to reaction with an electron attractive group contained in a resist material. The processes of forming a resist film on a substrate, patterning the resist film on the substrate by an electron beam cutting, forming a nickel alloy thin film on the patterned resist film, forming a nickel layer on the nickel alloy thin film by the electrocasting, and injection molding of a resin, using the nickel layer peeled off from the nickel alloy thin film as a stamper, are provided. The nickel alloy thin film has a composition containing Ni element as the main component as well as Ru element by less than 25% by weight.

Abstract: Preformatted areas in at least the most distal recording layer from an object lens among a plurality of recording layers in an optical disc include guard areas at both ends of the respective recording layer in the tracing direction. No data is recorded on the guard areas. The guard area length GL is determined to satisfy the following formula: GL≧YL+T×(NA/n)/[1−(NA/n)2]1/2 where YL is a maximum allowable value of position deviation between the preformatted areas in the most distal recording layer and in another recording layer in the tracing direction; NA is the numerical aperture of the object lens; T is a distance between the most distal and the another recording layer; and “n” is an refraction index of a medium between the most distal and the another recording layers.

Abstract: Provided is an optical recording medium whose surface is not easily injured, particularly an optical recording medium which is not required to be put into a cartridge. The optical recording medium comprises a recording layer, a covering layer comprising a polymer material, and a protective layer which are successively deposited, recording or reproducing wavelength for the medium being 420 nm or less, the numerical aperture of an optical system for the medium being 0.74 or more, and light being radiated to the side of the protective layer to read out data in the recording layer. In the medium, the protective layer has a hardness of 1000 kg/mm2 or more and a thickness of 4.66 &mgr;m or less.

Abstract: A recording disc and recorded information reproducing apparatus and method for immediately starting reproduction of information when a push-pull based tracking control is employed to reproduce recorded information from the recording disc. The recording disc comprises an information data area for recording recording marks which carry information data in columns, and a control data area for recording identification information indicative of a recording pattern of the recording marks in the information data area.

Abstract: A substrate of an optical disc is formed by injection molding. One of the surfaces of the substrate has a plurality of pits corresponding to information signals. The other surface has a plurality of dummy pits.

Abstract: A store apparatus determines the number of points given to a customer who has purchased a commodity using a customer apparatus via the Internet, in which the number of points are determined based on a roulette game. Since the point value given to the customer who purchases the commodity is determined by the roulette game regardless of the cost of the commodity purchased, the specific time period when purchased or the specific commodity purchased, it is possible to keep the willingness of the customer to purchase commodities and to direct that willingness to all commodities. In addition, since the customer can acquire higher points than the points usually given depending on the result of the roulette game, it is possible to further rouse the willingness of the customer to purchase commodities. Further, the customer is capable of shopping with more fun.

Abstract: An optical pickup is provided with: a light emitting device for emitting a light beam onto a record medium comprising a transparent layer, which is transparent for the light beam and through which the light beam is transmitted; a light receiving device for receiving a reflection light of the light beam from the record medium; a liquid crystal compensating device for compensating birefringence, which is generated in the light beam when the light beam is transmitted through the transparent layer, by controlling an orientation direction of liquid crystal molecules in a liquid crystal layer so as to give a canceling phase difference to the light beam transmitted through the liquid crystal layer; a generating device for generating an indication signal indicative of the birefringence; and a controlling device for controlling the orientation direction on the basis of the indication signal so that a first angle between a standard line, which is perpendicular to an optical axis of the light beam and is set in advance,

Abstract: There are provided a disc-manufacturing mold capable of manufacturing a disc substrate having no irregularities in thickness in its circumferential direction and a disc manufacturing apparatus using the mold. The disc-manufacturing mold is used for forming a disc substrate by injection molding. A cooling water ditch is arranged on the mold. The cooling water ditch is configured such that a disc distorts substantially evenly in its circumferential direction when the disc is manufactured.

Abstract: A stamper-forming electrode material contains Ag as its main ingredient and at least one other element, preferably Au and/or Cu. It is preferred that the Au and Cu contents each be 5.0 wt % or less. A stamper-forming thin film is made of this stamper-forming electrode material, whereby its corrosion resistance is improved to suppress damage to itself, and a high-quality stamper can hence be formed.

Abstract: A stamper-forming electrode material contains Cu as its main ingredient and at least one other element, preferably Ag and/or Ti. It is preferred that the Ag content be 10.0 wt % or less and that the Ti content be 5.0 wt % or less. A stamper-forming thin film is made of this stamper-forming electrode material, whereby its corrosion resistance is improved to suppress damage to itself, and a high-quality stamper can hence be formed.

Abstract: An ultrasonic injection mold for an optical disk includes a movable die and a fixed die; a disk molding cavity formed between the movable die and the fixed die; a stamper positioned at the bottom of the cavity for forming a pit on a surface of the disk; and an ultrasonic generation device provided on the movable die or fixed die for applying ultrasonic waves to the cavity in performing infection molding. One or more slits are formed on the movable die and the fixed die in the direction which crosses the radial direction of the cavity. The ultrasonic injection mold minimizes the amplitude of the ultrasonic transmitted in the radial direction of the cavity.

Abstract: A substrate of an optical disc is formed by injection molding. One of the surfaces of the substrate has a plurality of pits corresponding to information signals. The other surface has a plurality of dummy pits.

Abstract: Preformatted areas in at least the most distal recording layer from an object lens among a plurality of recording layers in an optical disc include guard areas at both ends of the respective recording layer in the tracing direction. No data is recorded on the guard areas.

Abstract: Provided is an optical recording medium whose surface is not easily injured, particularly an optical recording medium which is not required to be put into a cartridge. The optical recording medium comprises a recording layer, a covering layer comprising a polymer material, and a protective layer which are successively deposited, recording or reproducing wavelength for the medium being 420 nm or less, the numerical aperture of an optical system for the medium being 0.74 or more, and light being radiated to the side of the protective layer to read out data in the recording layer. In the medium, the protective layer has a hardness of 1000 kg/mm2 or more and a thickness of 4.66 &mgr;m or less.

Abstract: To present a material for stamper free from deterioration of stamper quality due to reaction with an electron-attracting radical contained in the resist material. An electrode formed on the surface of a patterned resist film 2 for electrocasting a stamper material is formed of a nickel alloy thin film 3 comprising Ni element as a principal component, and Ru element added in a range of less than 25 percent by weight.

Abstract: To present a material for stamper free from deterioration of stamper quality due to reaction with an electron-attracting radical contained in the resist material. An electrode formed on the surface of a patterned resist film 2 for electrocasting a stamper material is formed of a nickel alloy thin film 3 comprising Ni element as a principal component, and Ru element added in a range of less than 25 percent by weight.

Abstract: The present invention is to provide a production method for an optical disc, capable of obtaining a good S/N ratio without deterioration of the stamper quality due to reaction with an electron attractive group contained in a resist material. The processes of forming a resist film on a substrate, patterning the resist film on the substrate by an electron beam cutting, forming a nickel alloy thin film on the patterned resist film, forming a nickel layer on the nickel alloy thin film by the electrocasting, and injection molding of a resin, using the nickel layer peeled off from the nickel alloy thin film as a stamper, are provided. The nickel alloy thin film has a composition containing Ni element as the main component as well as Ru element by less than 25% by weight.

Abstract: An information recording medium using a substrate having light transmittancy permitting high density recording to be achieved and a recording method permitting such an information recording medium using a substrate having light transmittancy to be recorded in a high density are provided. The information recording medium is formed by layering an ITO film and EB resist on a transparent insulating substrate formed of a glass material having light transmittancy. At the time of recording information, as the ITO film is set at a ground potential, an electron beam having recording information is irradiated upon a surface of the EB resist for a prescribed scanning to perform electron beam exposure, and pits corresponding to the information to be recorded are formed at the exposed positions.

Abstract: An optical disc is prepared by the steps of coating a positive photoresist comprising a photosensitive material and a base resin, satisfying a value of A in a formula A=(a1−a3) m10 and a value of B in a formula B=(a2m20+a3m10), being constant, is in a range of B value <0.3 on a glass substrate to form a resist film, forming a pit pattern through a light exposure to the resist film, developing the resist film after the light exposure to form a resist original, effecting a plating treatment to the resist original to form a stamper through an electrocasting treatment, forming a replica disc through an injection molding process by utilizing the stamper, forming a reflection film on the replica disc, and forming an overcoat layer on the reflection film.

Abstract: A method of manufacturing an optical disc master plate, comprises the steps of: forming a photoresist layer having an electrically conductivity on a substrate; and irradiating the photoresist layer with a laser beam, using an optical system capable of holding a solid immersion lens on a flying head.