Abstract: In an eccentricity measuring method according to the present invention, a first position of a light source image formed by reflection at one optical surface is measured (S2), a predetermined second position related to another optical surface is measured (S3), and a relative eccentricity between both optical surfaces is calculated based on the first and second positions (S5). Therefore, the eccentricity measuring method enables measurement of eccentricity by a same measurement optical system regardless of a radius of curvature of an optical surface of an optical element.

Abstract: In an eccentricity measuring method according to the present invention, a first position of a light source image formed by reflection at one optical surface is measured (S2), a predetermined second position related to another optical surface is measured (S3), and a relative eccentricity between both optical surfaces is calculated based on the first and second positions (S5). Therefore, the eccentricity measuring method enables measurement of eccentricity by a same measurement optical system regardless of a radius of curvature of an optical surface of an optical element.

Abstract: A recorder has a recording medium for information recording, a light source, an optical system, a slider, and an optical waveguide. To the optical system, light from the light source enters, and the slider moves relative to the recording medium while not in contact therewith. The optical waveguide is arranged at position facing the recording medium in the slider so that light entering from the optical system is irradiated on the recording medium. Where the mode field diameter of the optical waveguide on the light output side is d and the mode field diameter thereof on the light input side is D, the mode field diameter is converted by smoothly changing the diameter of the optical waveguide to satisfy D>d.

Abstract: Provided is an optical recording head in which a light beam from a light source is collected by an optical element and reflected on a reflecting surface to be formed into a spot light. Since a support portion for supporting the light source of the optical element at a predetermined position and the reflection surface for reflecting the light beam are formed integrally with each other, it is not required to perform the positioning thereof, and light can be collected to a very small spot with high efficiency, and an optical recording head and an optical recording apparatus having low heights can be provided.

Abstract: A recorder has a recording medium for information recording, a light source, an optical system, a slider, and an optical waveguide. To the optical system, light from the light source enters, and the slider moves relative to the recording medium while not in contact therewith. The optical waveguide is arranged at position facing the recording medium in the slider so that light entering from the optical system is irradiated on the recording medium. Where the mode field diameter of the optical waveguide on the light output side is d and the mode field diameter thereof on the light input side is D, the mode field diameter is converted by smoothly changing the diameter of the optical waveguide to satisfy D>d.

Abstract: A recorder has a recording head which uses light for information recording to a recording medium. The recording head has a slider and an optical waveguide. The slider moves relative to the recording medium while floating thereon. The optical waveguide is provided in the slider and has a refractive index difference of 20% or more between a core and a cladding.

Abstract: An optical recording head simply structured, enabling a reduction in thickness, and having sufficient efficiency even if a light source with small output is used when a plasmon probe is used. The optical recording head includes a light source section for emitting light, a slider moving relative to a recording medium, and an optical waveguide disposed in the slider, guiding the light from the light source section and irradiating the surface of the recording medium with the light, and having a light emission angle not perpendicular to the surface, of the slider, facing the surface of the recording medium.

Abstract: To obtain an optical element for generating near-field light which can accurately detect positions of a plurality of minute structures formed on a metallic thin film provided to a condensing surface, and a method of adjusting an optical spot position of the optical element. The metallic thin film is formed on the condensing surface of the optical element that condenses incident light so as to generate near-field light smaller than an condensing spot B near a condensing point, and a plurality of openings (minute structure) for generating the near-field light are formed into a matrix matter on the metallic thin film, and position detecting structures are formed on positions that partitions the openings is formed. Scanning in X and Y directions is carried out by a light beam, and its reflected light is detected so that the positions of the openings are detected.

Abstract: Provided is an optical recording head in which a light beam from a light source is collected by an optical element and reflected on a reflecting surface to be formed into a spot light. Since a support portion for supporting the light source of the optical element at a predetermined position and the reflection surface for reflecting the light beam are formed integrally with each other, it is not required to perform the positioning thereof, and light can be collected to a very small spot with high efficiency, and an optical recording head and an optical recording apparatus having low heights can be provided.

Abstract: An optical head having: a graded index lens which receives incident light radiated from a linear optical guide at one end surface of the graded index lens and transmits the incident light from the other end surface of the graded index lens, the graded index lens is adapted to form a light spot at a position that is away from the other end surface from which the incident light is transmitted; a light path deflection section which deflects light transmitted from the graded index lens, the light path deflection section is arranged between the other end surface from which the incident light is transmitted and the position where the light spot is formed; and a slider which floats on a recording medium while moving relative to the recording medium, wherein at least the graded index lens and the light path deflection section are installed on the slider.

Abstract: A recorder has a recording medium for information recording, a light source, an optical system, a slider, and an optical waveguide. To the optical system, light from the light source enters, and the slider moves relative to the recording medium while not in contact therewith. The optical waveguide is arranged at position facing the recording medium in the slider so that light entering from the optical system is irradiated on the recording medium. Where the mode field diameter of the optical waveguide on the light output side is d and the mode field diameter thereof on the light input side is D, the mode field diameter is converted by smoothly changing the diameter of the optical waveguide to satisfy D>d.

Abstract: A recorder has a recording head which uses light for information recording to a recording medium. The recording head has a slider and an optical waveguide. The slider moves relative to the recording medium while floating thereon. The optical waveguide is provided in the slider and has a refractive index difference of 20% or more between a core and a cladding.

Abstract: To obtain an optical element for generating near-field light which can accurately detect positions of a plurality of minute structures formed on a metallic thin film provided to a condensing surface, and a method of adjusting an optical spot position of the optical element. The metallic thin film is formed on the condensing surface of the optical element that condenses incident light so as to generate near-field light smaller than an condensing spot B near a condensing point, and a plurality of openings (minute structure) for generating the near-field light are formed into a matrix matter on the metallic thin film, and position detecting structures are formed on positions that partitions the openings is formed. Scanning in X and Y directions is carried out by a light beam, and its reflected light is detected so that the positions of the openings are detected.

Abstract: A refracting objective optical system used in recording and/or reproducing information by near field light includes an aspherical lens in which an entrance surface is a continuous aspheric surface of convex shape and an exit surface is a flat surface, and a transparent flat plate joined to the flat surface of the relevant lens. The ray entering a first surface of the lens is refracted at the first surface, transmitted through a second surface and the flat plate, and condensed at a microscopic spot near an exit surface of the flat plate. The transparent flat plate includes a microscopic structure for generating a surface excitation plasmon near a light condensing point of the exit surface.