Abstract: A lens includes a lens portion which condenses light; a reflecting flat portion which is formed in a periphery of the lens portion and reflects parallel light to be irradiated to the reflecting flat portion in a direction opposite to the irradiation direction; and a flange portion which is adhered to a lens holder by an adhesive. An applied portion of the adhesive which is formed on the flange portion is inclined with respect to the reflecting flat portion.

Abstract: In the invention, a movable lens varying the rate of convergence or divergence of light reaching an objective lens by moving in an optical axis direction has its position adjusted to correspond to ambient temperature. The objective lens is arranged to be tilted with respect to an optical axis of light reaching the objective lens from the movable lens. First coma aberration of which the amount produced varies according to movement of the movable lens, and second coma aberration of which the amount produced varies due to variation in the warping state of an optical disc that is caused along with variation in ambient temperature both occur in the radius direction of the optical disc, and the objective lens has its tilting direction adjusted such that the first coma aberration and the second coma aberration have their increasing and decreasing directions of the amount of coma aberration produced with respect to variation in ambient temperature reversed.

Abstract: A multilayer optical recording system to record information with light includes a lens unit, a recording medium, and a microscopic drive unit. The lens unit includes a metamaterial lens or a plasmon lens. The metamaterial lens has a first dielectric member in which first microstructures are implanted in a substantially regular manner. The plasmon lens has an aperture. The aperture is a hole or a slit created in a metal film. The microscopic drive unit is configured to adjust a relative position between the lens unit and the recording medium. In addition, the principal plane is placed to be in contact with the lens unit or to have a gap between the principal plane and the lens unit. Furthermore, the second microstructures are arranged periodically in a direction substantially perpendicular to the principal plane of the recording medium.

Abstract: An optical element includes: an element body including a resin containing a polymer having an alicyclic structure. The optical element is treated by one of heat treatment and wet-heat treatment for 15 hours or longer at a temperature lower by 10° C. to 30° C. than a glass transition temperature of the resin after being formed by injecting the resin in a mold. The optical element body has a length along an optical axis of the optical element in a range of 0.5 to 3 mm, and a length in a perpendicular direction to the optical axis in a range of 3 to 5 mm.

Abstract: The invention provides a method for controlling spherical aberration correction for an optical disk drive. First, a collimator lens is moved to a first target position for spherical aberration correction. A driving time of motion of the collimator lens is then calculated. A prohibiting time is then determined according to the driving time. The collimator lens is then prevented from moving until the prohibiting time elapses.

Abstract: A method of fabricating an information storage medium, the method including forming a plurality of nanorod recording layers on a substrate by sputtering using a mask having a plurality of nanorod patterns.

Abstract: A near field light generating device generating near field light from incident light by using a solid immersion mirror and a heat assisted magnetic recording head with the same are provided. The near field light generating device includes a light source; a waveguide core which transmits light; and a solid immersion mirror, which generates near field light, including an upper transmission surface through which light from the waveguide core is transmitted into the solid immersion mirror, a lower reflection surface, opposite the upper transmission surface, which reflections light incident thereon, lateral reflection surfaces, facing each other at sides of the solid immersion mirror, which reflect light incident thereon, and a lower transmission region disposed at a center of the lower reflection surface. Light reflected from the lateral reflection surfaces forms a light spot on the lower transmission region.

Abstract: An optical information recording/reproduction apparatus includes a correction device that corrects aberration, due to a change in thicknesses of a transparent substrate and spherical aberration generated by inserting an optical attenuation device into an optical path or retreating the optical attenuation device from the optical path, by changing intervals between a plurality of lenses. The correction device is disposed between an objective lens and a light source. The correction device also functions as a collimator lens. The optical attenuation device is provided in an optical path of diverging light flux from the light source to the correction device, for attenuating an optical output from the light source. A discrimination circuit discriminates (i) a kind of the optical recording medium and (ii) an insertion of the optical attenuation device into the optical path or a retreating of the optical attenuation device from the optical path, and produces a discrimination result.

Abstract: The present invention provides an optical pickup system including a first light source emitting a light flux with a first wavelength; a second light source emitting a light flux with a second wavelength; and a light-converging optical system converging the light flux with the first wavelength from the first light source with a first magnification onto a first reference surface set at a first depth, and converging the light flux with the second wavelength from the second light source with a second magnification onto a second reference surface set at a second depth. The first and second wavelengths, the first and second depths, and the first and second magnifications satisfy: a first condition according to an aberration and a second condition according to a working distance.

Abstract: Provided is an actuator for a mobile device including a holder having a coil wound along inner side surfaces thereof; a driving unit that is inserted into the holder such that four side surfaces of the driving unit are spaced at a predetermined distance from side walls of the holder, the driving unit having magnets coupled to the respective side surfaces thereof; a pair of suspension wires that are mounted symmetrically with each other on the upper portion of the driving unit such that an arbitrary portion of each suspension wire is bent and directed toward a corner of the driving unit; and a pair of support plates that are coupled to both lower sides of the driving unit such that elastic forces are generated in opposite directions to each other.

Abstract: The present invention relates to a coupling optical system, an optical element, and an optical pickup apparatus. A coupling optical system is provided for use in an optical pickup apparatus and is arranged between a light source and an objective lens of the optical pickup apparatus. The coupling optical system includes: a first optical element with a power; and a second optical element with a positive power. The first optical element includes an optical surface, an out-effective-aperture section surrounding the optical surface, and a light-reduction structure arranged on the out-effective-aperture section. When a non-parallel light flux emitted from the light source enters into the out-effective-aperture section, the light-reduction structure reduces a light flux to be emitted from the second optical element in a direction getting closer to an optical axis of the second optical element.

Abstract: An optical pickup apparatus includes a first objective lens having a low numerical aperture (NA) suitable for a low density recording medium, a second objective lens having a high NA suitable for a high density recording medium, a first light source that emits short wavelength light which is focused onto an optical recording medium by the first and second objective lenses, a first photodetector that receives a returning reflected light from the optical recording medium, and a first optical path converter for selectively guiding part of the light emitted from the first light source towards the first or the second objective lens, and guiding the reflected light towards the first photodetector.

Abstract: An optical pickup includes at least a laser light source emitting a laser beam, a collimator lens system including a plurality of lenses for collimating the light beam emitted from the laser light source and incident thereupon as diffused light, and an objective lens. The laser beam transmitted through the collimator lens system is incident upon the objective lens. The collimator lens system includes a first lens unit held so as to be movable in an optical axis direction of the laser beam and a fixed second lens unit.

Abstract: An optical pickup apparatus in which a plurality of light sources emitting a plurality of light beams whose wavelengths are different from each other and degree of reliability of signals detected by a photodetector is high, a method of controlling the same, and an information recording and reproducing apparatus are provided. An objective lens, a ?/4 plate and a polarizing element whose outer edge portion is formed of a polarizer are formed integrally, which polarizing element is disposed so as to serve as an aperture stop with respect to a return light beam having a shorter wavelength.

Abstract: An optical element having an optical axis, comprises an element body having the maximum first length of 4 mm or less in the optical axis direction and the second maximum length of 6 mm or less in the direction perpendicular to the optical axis direction; wherein the element body is made of a resin containing a polymer having an alicyclic structure and is treated by one of heat treatment and wet-heat treatment for 16 hours or longer at a temperature lower by 35° C. to 45° C. than the glass transition temperature of the resin after the element body has been formed by injecting the resin in a mold, where the glass transition temperature of the resin is measured by differential-scanning-calorimetry method at heating rate 10° C./min on the basis of JIS K7121.

Abstract: An optical scanning device scans an information track which is present on an information carrier. The scanning device includes a radiation source, a lens system with an optical axis for focusing a radiation beam supplied by the radiation source into a scanning spot on the information carrier, and a focusing actuator for displacing the lens system relatively to a basic part of the scanning device in a direction parallel to the optical axis. The actuator includes an electric coil which is arranged around the lens system and provided with a passage for a radiation beam path which extends in a direction perpendicular to the optical axis. The electric coil is provided around the lens system by means of a winding process, the passage being provided in the coil by bending the parts of the coil wires which are present near the radiation beam path, in a direction substantially parallel to the optical axis.

Abstract: An optical pickup apparatus compatible with at least two types of optical recording media, using light beams having respective different wavelengths for recording and reading information, the optical pickup apparatus including two laser light sources to emit light beams having the different wavelengths, a holographic lens including a holographic ring to transmit the light beams incident in an inner region of the holographic ring, and to diffract a specific light beam among the light beams emitted from the laser light sources incident in an outer region relative to the inner region, an objective lens to focus the light beams passed through the holographic ring lens on the respective information recording surfaces of the two types of the optical recording media, optical elements to alter optical paths of the light beams reflected from the information recording surfaces of the optical recording media to corresponding photodetectors.

Abstract: There are comprised a laser light source for outputting a light beam, an optical disk having a recording/reproducing surface and a transparent substrate on the surface, an objective lens for gathering the light beam on the optical disk, a relay lens system comprising one or more lenses inserted between the laser light source and the objective lens, means for moving one or more lenses in the relay lens system toward its optical axis so as to correct sphere aberration in accordance with a thickness of the transparent substrate of the optical disk, and means for sustaining a diameter of an incident light on the objective lens when one or more lenses among the relay lenses move.

Abstract: An optical element structure allowing an increased power density of aperture-transmitted light while suppressing increase in temperature is disclosed. A conductive film has a sub-wavelength aperture formed therein and a periodic surface topography formed thereon. A lens focuses light onto the periodic surface topography with a predetermined diameter. The predetermined diameter of incident light on the conductive film and a period of the periodic surface topography are determined so that a power ratio of aperture-transmitted light to the light beam is greater than that of aperture-transmitted light which would be obtained if no periodic surface topography is provided in the conductive film.

Abstract: The invention provides an optical apparatus. and the optical pickup of that optical apparatus, for which the number of parts of the optical pickup can be reduced and thus a data-recording apparatus that contains this optical pickup can be made more compact. An optical pickup P1 that projects a red-LASER beam RL for a DVD and a blue-LASER beam for a high-recording-density optical disc, whose optical axes coincide with each other, onto the respective optical discs, and comprising: a first expander lens 4 and second expander lens 6 that correct distortion that occurs in the blue-LASER beam BL and red-LASER beam RL; and a dichroic prism 5 that is located between the first expander lens 4 and second expander lens 6 in the optical path of the blue-LASER beam BL and its reflected beam; and where the second expander lens 6, working together with the first expander lens 4, corrects spherical distortion that occurs in the blue-LASER beam BL, as well as converts the red-LASER beam RL to a parallel beam.

Abstract: The present invention relates to an optical pickup and a disc drive for preventing aberrations of laser light due to variations in temperature and humidity to ensure satisfactory characteristics of the laser light. A compound lens (14) is disposed in the optical path of the laser light, which is emitted by a light-emitting device (11) to be incident on a beam splitter (15), and in the optical path of the laser light, which exits from the beam splitter to be incident on a photodetector (13). The compound lens includes a diffractive section (23) for diffracting the laser light and a lens section (24) having a predetermined function for the laser light. The compound lens is formed by integrating individual sections including the diffractive section and the lens section. The compound lens is provided with a passage hole (14c) that lets in the laser light emitted by the light-emitting device to be incident on the beam splitter.

Abstract: A laser beam emitted from a laser source provided at a silicon substrate passes through a hologram element formed of a translucent flat plate and a grating, thereby being subjected to NA conversion executed by an NA converting lens, passing through a polarizing film of a polarization beam splitter, and converging onto a magneto-optical disk via a collimator lens and an objective. A part of back-reflection from the magneto-optical disk, which is reflected by a polarizing film of the polarization beam splitter, is reflected by a reflection surface of the splitter, then branched into two polarized light beams by a Wollaston prism, and guided to one light receiving element group. On the other hand, another part of the back-reflection, which passes through the polarization beam splitter, is branched into two beams by the hologram element and guided to the other light receiving element groups.

Abstract: The invention relates to an objective system (39) which is suitable for use in an optical scanning device (15). The lens system (39) comprises a first lens, or objective lens (45), and a second lens, or auxiliary lens (47), which are mounted in fixed positions in a lens holder (61). The objective lens comprises more than one half of a first spherical lens body (67) having a first diameter (D1) and the auxiliary lens comprises more than one half of a second spherical lens body (69) having a second diameter (D2) which is smaller than the first diameter. The objective lens and the auxiliary lens are surrounded by a first circular-cylindrical inner wall (83) and a second circular-cylindrical inner wall (85), respectively, of the lens holder, having a diameter which is substantially equal to the first and the second diameter, respectively. The inner walls can be provided in the lens holder in very accurate coaxial positions by use of conventional tools.

Abstract: An optical pickup device with the capability to read data from and write data to different kinds of optical discs in different formats and a composite optical device used in the optical pickup device. An optical pickup device is made by combining two laser couplers LC1 and LC2 that are designed for optimum read/write specifications for optical discs which are different in format from each other. In one embodiment, two laser couplers LC1 and LC2 are incorporated on a common photodiode IC to form a single laser coupler, and the laser coupler is used in an optical pickup device.

Abstract: A read head optical system capable of reading either CD or DVD disks is provided. A monolithic molded hollow plastic block includes three lenses integrally molded into its exterior surfaces. A 780 nm laser diode is aligned with the first lens for reading CD disks, a 655 nm laser is aligned with the second lens for reading DVD disks and a detector for providing signal, focus and tracking data is aligned with the third molded lens. The hollow plastic block has an interior cavity adapted to support optical elements to receive and transmit the output of the laser diodes to the disks and to the detector. The three lenses are formed in the hollow plastic block in various embodiments.

Abstract: An objective lens (1) for an optical disk, which focuses a light beam from a light source, is designed so that a third-order coma aberration generated when the objective lens is inclined at a unit angle is larger than a third-order coma aberration generated when the optical disk (2) is inclined at the unit angle, mounted on an actuator for inclining the objective lens according to an inclination amount of the optical disk, and used. With this structure, it is possible to obtain an objective lens for an optical disk that has a large numerical aperture and is easy to manufacture and assemble, and in which the third-order coma aberration generated when the optical disk surface is inclined owing to a warp or the like can be corrected by small inclination of the objective lens, so as to reduce a residual astigmatism, which is generated according to the inclination amount, after the correction.

Abstract: An optical lens system including: a first lens including a more than half part of a substantially spherical first lens body having a first diameter and a substantially flat first boundary surface; a second lens including a more than half part of a substantially spherical second lens body having a second diameter and a substantially flat second boundary surface, the second diameter being smaller than the first diameter; and a lens holder comprising a first and a second mount for, respectively, the first and second lens, wherein the first an the second mounts comprise, respectively, a first and a second circular cylindrical inner wall having a common center line, a diameter of the first inner wall and a diameter of the second inner wall being substantially equal to, respectively, the first and the second diameters.

Abstract: Disclosed is a method of attaching components of an optical head. In one embodiment, first and second optical assemblies of the optical head are positioned adjacent to each other. The first optical assembly may include a first optical element, and the second optical assembly may include a second optical element. Both of the first and second optical elements are configured to transmit light for reading or writing data to an optical data storage media. The position of a first optical assembly is adjusted with respect to the second optical assembly until the first optical element and second optical elements are in optical communication with each other. Thereafter, the first and second optical assemblies are rigidly connected while the first and second optical elements are in optical communication with each other.

Abstract: An optical pickup apparatus for recording and/or reproducing information on an optical information recording medium includes a light source emitting a light flux, a light-converging optical system to converge a light flux emitted from the light source, having a coupling optical system which changes a divergent angle of a light flux emitted from the light source and an objective lens optical system which converges a light flux emerging from the coupling optical system on an information recording surface of the optical information recording medium, and an optical detector for detecting reflected light or transmitted light coming from the information recording surface of the optical information recording medium.

Abstract: A minute optical head is provided so that a light source and one or more photo detector elements are integrated on the same substrate by a simple manufacturing process and may be applied to an apparatus for recording and reproducing recordable optical information. An apparatus for recording and reproducing optical information is arranged to have a minute optical head. A light waveguide layer composed of column semiconductor crystal is formed on a monocrystalline transparent substrate and an active layer is formed on the side of the light waveguide layer. The light beam source is a semiconductor having a vertical resonator formed of a high-reflection film before and after an emitting surface of the active layer so that a light beam is vertically radiated to the substrate. The photo detector element is integrated on the closer portion of the substrate to the light beam source of the semiconductor laser.

Abstract: An objective lens (1) for an optical disk, which focuses a light beam from a light source, is designed so that a third-order coma aberration generated when the objective lens is inclined at a unit angle is larger than a third-order coma aberration generated when the optical disk (2) is inclined at the unit angle, mounted on an actuator for inclining the objective lens according to an inclination amount of the optical disk, and used. With this structure, it is possible to obtain an objective lens for an optical disk that has a large numerical aperture and is easy to manufacture and assemble, and in which the third-order coma aberration generated when the optical disk surface is inclined owing to a warp or the like can be corrected by small inclination of the objective lens, so as to reduce a residual astigmatism, which is generated according to the inclination amount, after the correction.

Abstract: An optical disk reader or read/write system for CD or DVD formats. First and second laser diodes operating at different wavelengths have their output beams collimated and directed at a single element objective lens, and are then reflected off the disk back through the lens to a photodetector. The single element objective lens has a central aperture zone and an outer aperture zone, the central zone being profiled to operate at a first numerical aperture at approximately 0.45 and the output beam of the first laser diode is confined to the central aperture zone. The outer aperture zone together with the central aperture zone are profiled to operate at a second numerical aperture, for example 0.60 wherein the output beam of the second laser diode has ray fans extending across the full aperture of the single element objective lens.