Abstract: A magneto-optical head includes a slider, an objective lens, a coil and a transparent insulating layer. The coil is provided with upper and lower conductive patterns, wherein the lower pattern is brought closer to a storage medium than the upper pattern is. The lower pattern is made smaller in inner diameter than the upper pattern. The insulating layer fills the center of the coil.

Abstract: An optical head includes a lens carrier movable at least radially of a magneto-optical disk in facing relation thereto. An object lens is mounted on the lens carrier to converge a laser beam for forming a laser spot on the disk. The object lens has an optical axis and includes a lens surface directed toward the disk. A patterned coil is formed on the lens surface at least in one layer and has a light-passing opening corresponding to the optical axis of the object lens. A light-pervious layer is formed on the lens surface for closing the light-passing opening of the coil.

Abstract: An optical disk apparatus includes a light source for emitting light in a prescribed wavelength range, an objective lens system for causing the light emitted from the light source to be focused onto a storage disk, and a reproduction signal system for causing return light from the storage disk to be conduced to a detector. The light emitted from the light source has a direction of polarization parallel to a recoding track of the storage disk. The objective lens system has transmission factors for s-polarized light and p-polarized light that are defined relative to the objective lens system. The transmission factor for s-polarized light is greater than the transmission factor for p-polarized light.

Abstract: A magneto-optical head includes a slider, an objective lens, a coil and a transparent insulating layer. The coil is provided with upper and lower conductive patterns, wherein the lower pattern is brought closer to a storage medium than the upper pattern is. The lower pattern is made smaller in inner diameter than the upper pattern. The insulating layer fills the center of the coil.

Abstract: An objective lens system includes a first lens and a second lens. The first lens has a first surface for allowing entry of light and a second surface opposite to the first surface. The second lens has a spherical third surface and a flat fourth surface opposite to the third surface. The third surface faces the second surface and has a radius of curvature r0. The second lens has a thickness d0 and a refractive index n0. The thickness n0, the radius of curvature r0 and the refractive index n0 satisfy a relation: d0>r0>n0d0.

Abstract: An objective lens system includes a first lens and a second lens. The first lens has a first surface for allowing entry of light and a second surface opposite to the first surface. The second lens has a spherical third surface and a flat fourth surface opposite to the third surface. The third surface faces the second surface and has a radius of curvature r0. The second lens has a thickness d0 and a refractive index n0. The thickness n0, the radius of curvature r0 and the refractive index n0 satisfy a relation: d0>r0>n0d0.

Abstract: An optical information recording/reproducing apparatus records information on and/or reproduces information from an optical recording medium based on a reflected light beam from the optical recording medium. The apparatus includes a light splitting part having a plurality of light splitting stages which split the reflected light beam from the optical recording medium into a plurality of light beams, and a photodetector unit including a plurality of photodetectors which receive the plurality of light beams from the light splitting part. The photodetector unit includes a plurality of photodetectors which receive light beams used to detect a focal error, at least one photodetector which receives a light beam used to detect a tracking error, and a plurality of photodetectors which receive light beams used to detect magneto-optic information recorded on the optical recording medium.

Abstract: An optical head unit used for an optical disk apparatus is provided. The optical head unit includes an object glass assembly for focusing a laser beam from a light source on an optical disk, an actuator movable at least in a focus control direction, a carriage for supporting the actuator and moving the actuator in a track control direction, and a slider which is attached to the carriage and capable of adjusting its posture in relation to a surface of the optical disk. The object glass assembly is provided with a plurality of lens units. Each lens unit includes at least one lens. One of the plural lens units is supported by the slider.

Abstract: An optical information recording/reproducing apparatus records information on and/or reproduces information from an optical recording medium based on a reflected light beam from the optical recording medium. The apparatus includes a light splitting part having a plurality of light splitting stages which split the reflected light beam from the optical recording medium into a plurality of light beams, and a photodetector unit including a plurality of photodetectors which receive the plurality of light beams from the light splitting part. The photodetector unit includes a plurality of photodetectors which receive light beams used to detect a focal error, at least one photodetector which receives a light beam used to detect a tracking error, and a plurality of photodetectors which receive light beams used to detect magneto-optic information recorded on the optical recording medium.

Abstract: An optical information recording/reproducing apparatus records information on and/or reproduces information from an optical recording medium based on a reflected light beam from the optical recording medium. The apparatus includes a light splitting part having a plurality of light splitting stages which split the reflected light beam from the optical recording medium into a plurality of light beams, and a photodetector unit including a plurality of photodetectors which receive the plurality of light beams from the light splitting part. The photodetector unit includes a plurality of photodetectors which receive light beams used to detect a focal error, at least one photodetector which receives a light beam used to detect a tracking error, and a plurality of photodetectors which receive light beams used to detect magneto-optic information recorded on the optical recording medium.