Abstract: An optical pickup apparatus includes first and second light sources which selectively emit one of first and second light beams, the first and second light beams being different in wavelength, the wavelengths of the first and second light beams being appropriate for accessing first and second optical disks respectively. A coupling lens converts a corresponding one of the first and second light beams into a collimated beam. An objective lens forms a light spot on a corresponding one of the first and second optical disks by focusing the collimated beam. A holographic optical element receives a reflection beam of the light spot from one of the first and second optical disks and provides holographic effects on the reflection beam so as to diffract the reflection beam in predetermined diffracting directions depending on the wavelength of the reflection beam.

Abstract: An optical pickup has a laser mounting surface formed around an opening portion of a laser hole while a notch groove ranging from the laser mounting surface to an operating hole is formed in a laser hole side wall portion. A fitting piece removably fitted into the notch groove is provided integrally with a metal holder which is provided for supporting a photodiode and which is locked in the laser mounting surface. The operating hole is defined between a forward end of the fitting piece and an inner end of the notch groove. A laser diode is fitted into a lock hole of the holder coaxial with the laser hole while a radiator plate is attached to the outer surface of the holder. Thus, the laser diode is held between the holder and the radiator plate.

Abstract: An optical storage device capable of at least reproducing information recorded on first and second optical storage media different in distance from a medium surface on which a light beam is incident to a recording surface and in operating wavelength. The optical storage device includes a first light emitting element for emitting a light beam having a first wavelength, a second light emitting element for emitting a light beam having a second wavelength, a first photodetector for detecting a reproduction signal from a light beam reflected on the first optical storage medium, a second photodetector for detecting a reproduction signal from a light beam reflected on the second optical storage medium, and a beam splitter for combining optical paths of the light beams emitted from the first and second light emitting elements.

Abstract: An optical base (20) of an optical pickup has a sliding portion (21) that is slidable relative to a mounting object, a component mounting portion (27) mounted with optical components, a laser diode fixing portion (22) fixed with a laser diode 1, and a photodiode fixing portion (25) fixed with a photodiode (9). The sliding portion and the component mounting portion are formed by resin molding. The laser diode fixing portion and the photodiode fixing portion are formed by an iron plate.

Abstract: A laser drive circuit includes a first current supply unit which supplies a first drive current to a first laser diode based on a drive waveform signal generated by a drive waveform generating unit, a second current supply unit which supplies a second drive current to a second laser diode based on the drive waveform signal generated by the drive waveform generating unit, and a switching unit which selectively supplies the drive waveform signal generated by the drive waveform generating unit to one of the first current supply unit and the second current supply unit. The drive waveform generating unit may be part of the laser drive circuit, or may be separate from the laser drive circuit, and may include a drive waveform information storage unit which stores a recording strategy according to a type of disk.

Abstract: An optical pickup includes a light source module in which first and second light sources that emit first and second light beams of different wavelengths are integrated into a single package, an objective lens that focuses the first and second light beams to form a light spot on a recording surface of a recording medium, a light path changer that changes a path along which the first and second light beams propagate, a photodetector that receives the first and second light beams entered via the objective lens and the light path changer and detects an information signal and/or error signal, and an optical element disposed on a path along which the first and second light beams propagate to act as a lens with respect to only one of the first and second light beams so as to correct a position difference along a light propagation direction between the first and second light sources.

Abstract: An optical appliance that is capable of processing optical media can be used to modulate a laser. In some systems, the optical appliance includes an opto-electronic transducer, a compact disk (CD) or digital versatile disk (DVD) controller and front end. A a modulated laser can be used as an optical network with a terminal node in the form of a conventional optical detector such as a compact disk (CD) or digital versatile disk (DVD) pickup. A CD or DVD controller and front end can be used to modulate the laser. Accordingly, the controller and front end can modulate the laser to emulate reading of an optical disk medium.

Abstract: An optical pickup device has first and second light sources that emit first and second laser beams of different wavelengths, an object lens that concentrates the first and second laser beams on a data recording surface of an optical disk, an optical separator disposed between the first and second light sources and the object lens, and an optical monitor that detects a quantity of light of the second laser beam. The optical separator has a wavelength selecting film that, on one hand, reflects the first laser beam emitted from the first light source toward the object lens and, on the other hand, transmits the second laser beam emitted from the second light source to the object lens, and a reflector that reflects a part of the second laser beam emitted from the second light source toward the optical monitor.

Abstract: A small-sized, inexpensive optical pickup apparatus can be assembled with high accuracy. The optical pickup apparatus has a various-purpose semiconductor laser, an integrated optical assembly for guiding outgoing light to an optical disk and for separating reflected light, a light receiver for receiving light and converting the received light into an electrical signal, and a coupling member for retaining a positional relationship among the various-purpose semiconductor laser, the integrated optical assembly, and the light receiver. By using a various-purpose semiconductor laser, the optical pickup apparatus can be made in a small size at low cost, and can be accurately assembled. The apparatus is also capable of accurately and efficiently detecting the optical power of the various-purpose semiconductor laser.

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: A semiconductor laser array including a plurality of index-guided semiconductor lasers different in oscillation wavelength is made by collectively controlling their double transverse modes and collectively processing them to form their current-blocking structures and buried layers. Thus, a semiconductor laser having a flat element surface and excellent in heat radiation can be made in a reduced number of manufacturing steps. When the laser array of this multi-wavelength type and a detector PD are mounted with a predetermined positional relationship, return light from an optical disk can be converted into a single point to enable detection thereof at PD on one chip. Therefore, an optical disk driving apparatus remarkably reduced in size and weight and having a high reliability can be realized.

Abstract: A laser driving integrated circuit (8) to drive a laser element is mounted in an optical housing, and a wiring pattern of an actuator line (6) for supplying an actuator (1) with drive signals to drive the actuator (1) through a relay circuit board and a wiring pattern of a laser drive line (5) for supplying drive signals from the laser driving integrated circuit (8) to the laser element are formed on the same flexible wiring board (4), and, when the flexible wiring board (4) is folded, a shielding part (7) connected to the ground line is arranged to intervene between the overlapping wiring patterns of the actuator line (6) and the laser drive line (5) of the flexible wiring board (4).

Abstract: An optical pick-up apparatus has a first light source, a second light source, and an optical system including an objective lens. An optical functional surface of the objective lens is divided into at least first and second concentric optical functional regions. The second functional region is provided with a diffractive structure to correct a spherical aberration of a converged light spot on an information recording plane to be regulated in a range where reproduction and/or recording information for a first optical information recording medium can be conducted when the refractive index of the optical element and the wavelength of the first light source vary due to a change of the working temperature of the optical system.

Abstract: An optical pickup for reading information written on an optical disk is equipped with a vertical multi-mode converted laser diode which emits light, means for focusing the emitted light from the laser diode onto the optical disk, and means for receiving reflected light from the optical disk in order to read the information written on the optical disk, wherein the coherent distance of the emitted light from the laser diode is made shorter than the optical path length of the optical pickup.

Abstract: An optical pickup device has a first combination reception and emission device (1) which emits laser beams (10) to an optical disk, and a second combination reception and emission device (2) which emits laser beams (11) having a wavelength different from that of the laser beams (10) to an optical disk. A DBS (3) is disposed on a path of the laser beams for making axes (12, 13) of the laser beams coincident with each other at an output side. A monitoring light detection element (9) is disposed near and above the DBS such that a light-receiving surface of the monitoring light detection element is substantially parallel with the optical axes (12, 13) of the laser beams (10, 11). The monitoring light detection element (9) receives laser beams outside of an effective region emitted by the first and second combination reception and emission devices (1, 2).

Abstract: An optical pickup apparatus conducts recording or reproducing information for an information recording plane of a first or second optical information recording medium and comprises a first light source and a second light source mounted on a same base board; a converging optical system; and a coupling lens. The converging optical system comprises an objective lens to converge a first or second light flux having passed through the coupling lens on a first or second optical information recording medium; and a diffractive structure to change a focal length in accordance with a wavelength of a light flux emitted from the first light source or the second light source.

Abstract: The present invention relates to an appliance for reading from and/or writing to optical recording media 1 having a first laser diode LD1 for producing a first scanning beam AS1 at a first wavelength &lgr;1 and having a second laser diode LD2 for producing a second scanning beam AS2 at a second wavelength &lgr;2, with the scanning beams AS1, AS2 running along a common optical axis 9, scanning an information layer 6 on the recording medium 1 and falling on a single photodetector 8 in order to produce an information signal IS, with a beam combination element being arranged at one point on the optical axis 9. According to the invention, the beam combination element is a diffraction grating 12.

Abstract: The inventive data memory (1) has an optically writeable and readable information carrier, which has a polymer film (11) whose refractive index can be locally altered by heating. An absorber is assigned to the polymer film (11) and is disposed for at least partially absorbing a write beam and for transferring, in an at least partially local manner, the heat generated thereby to the polymer film (11). The absorber is oriented in order to preferably absorb light with a polarization direction that is matched to the orientation of the absorber.

Abstract: A write-once high density optical storage medium. The optical storage medium is applicable in an optical read or write system with blue laser having a wavelength in between 385 nm to 425 nm and an objective lens with numerical aperture (NA) greater than 0.8 and includes the following film structure: a substrate; a reflective layer disposed on the substrate; a dye recording layer disposed on the reflective layer; a protective layer disposed on the dye recording layer; and a cover layer disposed on the protective layer. The protective layer prevents direct contact between the dye recording layer and cover layer, thus assuring the medium quality.

Abstract: A VCSEL-based monolithic optical pickup system for use with optical recording media with a retaining member, a plurality of VCSELs disposed on the retaining member for emitting laser beams, a plurality of detectors disposed on the retaining member for receiving reflected laser beams, and a stepped micro-mirror for reflecting laser beams emitted by the plurality of VCSELs toward optical recording media and for reflecting laser beams reflected from the recording media toward the plurality of detectors. The VCSELs and detectors can be disposed in laser/detector pairs wherein each detector surrounds its respective VCSEL.

Abstract: A semiconductor laser device includes a semiconductor laser element, a light beam branching element for branching a light beam emitted from the semiconductor laser element and reflected by an optical recording medium into a plurality of light beams, a light beam reflector for reflecting the light beam branched by the light beam branching element, and a photodetector portion for detecting the light beam reflected by the light beam reflector. The light beam branching element and the photodetector portion are formed on the same substrate. The miniature semiconductor laser device can be assembled without complicated position adjustment and has less deterioration of characteristics arising from misregistration during and after assembly.

Abstract: A method and apparatus utilizing a multiple quantum well modulator/emitter/detector pixel in a bilinear array permits reading or writing to an optical disc in parallel such that information may either be written to or read from an optical disc within one revolution of the optical disc. Thus while existing DVD and CDROM systems operate by sensing the contents of a spiral track, parallel readout afforded by the multiple quantum well modulator/emitter/detector provides as much as 1,000:1 advantage over single detector systems, with the biasing of the modulator/emitter/detector device determining whether the device is an emitter, detector or modulator. The co-location of the modulator/emitter/detector in a single device permits arranging devices in a linear array which is disposed over the optical disc for the parallel read/write functions.

Abstract: An optical data-storage hard disk drive that uses stationary Phase-Change Microhead Array Chips in place of conventional flying-heads, rotary voice-coil actuators, or other similar types of servo-tracking mechanisms to simultaneously record and/or reproduce data to and/or from a multitude of data-tracks located across the data-surfaces of a multitude of phase-change based disc media using a multitude of microheads.

Abstract: In an optical pickup projecting a laser beam from a laser diode onto a disk through a half mirror, a collimator lens and an objective lens and receiving the laser beam reflected by the disk in a photodiode through the half mirror thereby reading information recorded in the disk, a portion of a metal board body having a pattern of a printed board corresponding to a connector pin fed with a high-frequency signal is notched to cause no electrostatic capacitance between the metal board body and the printed board thereby preventing a read signal from the photodiode from a jitter. Thus obtained is a high-performance and low-priced optical pickup causing no reading error.

Abstract: An optical scanning device for scanning of a first, second and third type of optical record carrier with radiation of a first wavelength &lgr;1, a second wavelength &lgr;2 and a third wavelength &lgr;3, respectively, where the three wavelengths are substantially different.

Abstract: The present invention relates to a modulated signal generator capable of carrying out signal processing at a higher speed or capable of supporting a special format and a new format with ease. A modulation processing storing unit 130 has a modulation processing program required for producing an optical disc master 320 stored therein in advance. Information data recorded in an master optical disc 310 is reproduced by an information reproducing unit 110 and is outputted to a modulation controller 120. The modulation controller 120 carries out the signal modulation processing onto the reproduced information data in accordance with the signal modulation processing program so as to generate a data stream and stores the data stream in a modulated information storing unit 140 as necessary.

Abstract: A method of mounting an optical device having a step on the surface opposing to a mounting substrate favorably by face-down bonding which enables a decrease in the number of components or integrate additional components on one identical substrate and, accordingly, is useful for reducing the size and the thickness of an optical head using a light source, the method typically includes the step of making the area ratio of each electrode to a solder pattern different for every wiring electrode portions upon mounting the electrodes on the substrate for mounting the optical device, in which the optical device having the step can be mounted favorably to the substrate by the control for the height of solder upon melting, and the volume of the solder is previously controlled depending on the wettability of a region of the substrate covered by the solder.

Abstract: Two standard marks are set on two adjacent respective recording tracks, aligned in a direction perpendicular to the said recording tracks in the unit area for recording and reading that includes said the two recording tracks. Recording on the recording track is performed by forming round-marks that have information shown by which side of the two tracks they exist in and by what distance they are from each of the said two standard marks in the set area including the said two recording tracks. Reading information on the recording track is performed by reading two recording tracks at the same time or alternately.

Abstract: The field emission planar electron emitter device is disclosed that has an emitter electrode, an extractor electrode, and a planar emitter emission layer, electrically coupled to the emitter electrode and the extractor electrode. The planar electron emitter is configured to bias electron emission in a central region of the emission layer in preference to an outer region thereof. One structural example that provides this biasing is achieved by fabricating the planar emitter emission layer so that it has an outer perimeter that is thicker in depth than at an interior portion of the planar emitter emission layer, which reduces electron beam emission at the outer perimeter when an electric field is applied between the emitter electrode and the extractor electrode. The electric field draws emission electrons from the surface of the planar emitter emission layer towards the extractor electrode at a higher rate at the interior portion than at the outer perimeter.

Abstract: The invention is a multiple wavelength optical pickup head. It contains at least three laser beam generating units for generating laser beams with different wavelengths, a beam guiding unit installed on the optical path of the pickup head to guide the propagation of the laser beams, and a photo-detector that converts light signals into the corresponding electrical signals. The beam guiding unit includes a diffractive optical element and a convergent objective lens. After the laser beam generating units send out laser beams, the beam guiding unit leads them to the diffractive optical element so that the laser beams have different diffraction angles and effects. Through the focus of the convergent objective lens, the laser beams are converged to the data surfaces of optical recording media and reflected to the photo-detector, retrieving data from at least three kinds of optical recording media each with a kind of data storage densities.

Abstract: An optical pickup device includes a semiconductor laser for emitting forward and backward laser light from front and back emergent end faces thereof, focusing device for focusing the forward laser light emergent from the front emergent end face of said semiconductor laser onto an optical recording medium, a light-receiving element for signal reproduction for detecting return light from the optical recording medium, and a light-guiding system for guiding the return light to said light-receiving element for signal reproduction, said optical pickup device being provided with a light source unit having an arrangement in which said semiconductor laser and said light-receiving element for signal reproduction being incorporated in a common package and shielding device, disposed inside said package of said light source unit, for preventing the light emitted from said semiconductor laser from being incident upon said light-receiving element for signal reproduction.

Abstract: A near-field laser and detector apparatus and method wherein both writing and reading of optical media can be carried out using the same laser operating in a single mode for both read and write operations. The single operational mode can be utilized with both edge emitting and surface emitting laser configurations, and allows readout via rear facet output power variation or by voltage variation across the laser. A small aperture laser is operated during read and write operations at a bias current which is higher than the threshold currents associated with feedback from high and low reflectivity regions of an optical medium. The bias current and laser structure provide a relatively high, continuous output power from the front emission facet of the laser to facilitate writing, while providing substantial fluctuation or change in output power from the rear emission facet to facilitate readout.

Abstract: An optical disc comprises an information recording layer having a record of information as a pit train with a predetermined track pitch and a light-transmissive layer formed on the information recording layer so that the information can be reproduced by a beam of light illuminated through the light-transmissive layer to the information recording layer by an objective lens. The optical disc is characterized in that a relationship of 0.194 (/NA)2 TP×Tmin 0.264 (/NA)2 is satisfied, provided that the track pitch is >TP, a pit shortest length is Tmin, a wavelength of the light beam is and a numerical aperture of the objective lens is NA. The optical disc is characterized in that a pit width is 120 nm or smaller in a range of a track pitch of 0.280 to 0.325 m.

Abstract: An indirect semiconductor laser having an indirect semiconductor used as the material of an active layer is used, instead of a conventional direct semiconductor laser so as to obtain a reproducing optical source, in order to reduce optical interference noise of the laser caused in the optical head in an optical disc apparatus, and to eliminate the necessity of high frequency wave convolution, thereby it is possible to reduce the cost.

Abstract: In an optical pickup according to the present invention, a driving device, which independently supplies predetermined driving signals to a first light source and a second light source, is disposed in a notch specified by two planes, so as to suppress the deterioration of the driving signals. The two planes are defined by a vertical line, which is vertical to an intersection where an optical axis of the first light source and an optical axis of the second light source intersect, and the two axes.

Abstract: A compound optical unit includes a housing mounted to an optical pickup. A semiconductor laser, a light receiving member, and a composite optical member are integrally fixed to the housing. The semiconductor laser has a laser diode that emits a laser beam for a DVD. The composite optical member is provided with an incidence surface that admits light emitted from the semiconductor laser, an emission surface emits the light, a diffraction grating provided on the emission surface diffracts light reflected by an optical disk D, a reflecting surface that reflects light diffracted by the diffraction grating, and another emission surface that emits light reflected by the reflecting surface toward the light receiving member.

Abstract: A package structure of a hybrid device in an optical signal transmitter comprises an assembly of a surface emitting laser (SEL), photodiodes, an IC and a passive device, and its application. The package structure further comprises a submount to reduce parasitic capacitance and increase coupling efficiency of the device to the optical fiber, and an electric connect region is formed on the submount to shorten the length of wire and improve the yield. A combination of the SEL and the pair of photodiodes can further applies on a duplexer of single optical fiber.

Abstract: A first light ray with a wavelength &lgr;1 emanating from the first emission light source passes through the transparent substrate and is condensed by the objective lens on a signal surface of a first optical disk with a substrate thickness t1,

Abstract: A light source unit, which is employed in an optical head for an optical disc drive, is provided with a laser diode having a plurality of light emitting points. The plurality of light emitting points are spaced from each other by a predetermined minute amount. One of a plurality of laser beams having different wavelengths is selectively emitted from the plurality of light emitting points. The light source unit further includes a collimating lens that collimates each of the plurality of laser beams respectively emitted from the plurality of light emitting points. The plurality of laser beams passed through the collimating lens proceeds in different directions. The light source unit further-includes a transparent optical path compensation element having a predetermined dispersion characteristic. Each of the plurality of laser beams emerging from the collimating lens is emerged from the transparent optical path compensation element along the same optical path.

Abstract: The medium of a disk for CD-R is a pigmentation material so readout by a 650-nm laser diode (LD) is not possible. Since CD-R is becoming popular in the marketplace, there are demands for a DVD readout device that is capable of reading CD-R format disks. An integrated semiconductor laser element is created by forming a two-wavelength LD monolithically on a GaAs substrate, and that laser element emits a laser beam that is reflected by a 45° mirror incorporated in a flat package.

Abstract: An attachment portion 20 for a laser diode 1 is formed on a frame 2 of an optical pickup device. The attachment portion 20 includes a pair of inner peripheral faces 233 and 234 to which an outer peripheral face 103 of a circular stem 101 of the laser diode 1 can be press-fitted, and a pair of convex faces 241 and 242 rockably supporting an annular end face 104 of the stem 101 around a rocking center line L1. When the laser diode 1 is press-fitted and is then rocked around the rocking center line L1, the intensity distribution center of a laser beam 11 emitted from the laser diode 1 can be coincident with an optical axis L of an optical system.

Abstract: A disk recording apparatus for recording data to a disk is disclosed. The apparatus includes: a reading and writing element for emitting a read beam onto the disk to read out recorded data therefrom while emitting a plurality of write beams simultaneously onto the disk to record data thereto in parallel; and a controlling element for controlling where to emit on the disk the plurality of write beams in accordance with the data read out by the reading and writing element.

Abstract: An optical pick-up device (1) includes a laser diode (2) for recording which acts as a fixation side light source attached to an attachment portion (5) of a device frame (4) and has a great calorific value, and a laser diode (3) for reproduction which acts as an adjustment side light source held in a holder (6) fixed with an adhesive (7) in a clearance (46) provided on a side surface (45) of the device frame. Heat generated from the laser diode (2) for recording is radiated efficiently through the device frame (4), and heat generated from the laser diode (3) is also radiated efficiently through the holder (6) fixed with the adhesive (7) which is partially filled for the device frame (4) with the clearance (46) formed.

Abstract: An optical disc initialization apparatus includes a table on which an optical disc is placed. The table is guided on a base for linear motion and is moved back and forth by an electric motor. A light source and an optical system are disposed above the table. The light source consists of a plurality of semiconductor laser arrays, each including a plurality of emitters arranged in a row and each emitting a laser beam. The optical system introduces the laser beams from the light source and forms an elongated elliptical laser spot on the optical disc. The major axis of the elliptical laser spot has a length substantially equal to the diameter of a recording area of the optical disc. The table is moved linearly under the optical system in order to initialize the entire recording area of the optical disc through a single scanning operation.

Abstract: An optical information recording medium includes a plurality of recording layers, a reflectance of at least one of the plurality of the recording layers in a non-initialized state with respect to a light beam for initialization being smaller than a reflectance of the same in an initialized state with respect to the light beam for initialization. The recording layers are initialized by irradiating, among the plurality of recording layers, the recording layer positioned farther from a light beam irradiation side with the light beam prior to irradiating the recording layer positioned closer to the light beam irradiation side, so that the initialized recording layers have no initialization irregularities.

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: An optical recording film in the form of a monomolecular layer, includes chemisorptive molecules that are chemically bonded by covalent bonding to a surface of a substrate. The optical recording film has the property that, when irradiated with polarized light, a long axis orientation of the chemisorptive molecules is changed to a direction in which the polarized light is irradiated. A reflective film may be formed on the substrate surface. For the chemisorptive molecules it is possible to use CH3—COO—C6H4—(CH2)6—SiCl3, for example. The molecules undergo a dehydrochlorination with active hydrogen in the base material surface, and are chemically bonded to the base material surface by covalent bonding. Thus, an erasable or a write-once optical recording medium of high density can be provided by chemisorption without necessitating vacuum vapor deposition to form the recording layer.

Abstract: An information readout method for an optical information medium comprising an information recording layer having pits or recorded marks representative of information data involves the step of irradiating a laser beam to the information recording layer through an objective lens for providing readings of the pits or recorded marks. When the laser beam has a wavelength &lgr; of 400 to 410 nm, the objective lens has a numerical aperture NA of 0.70 to 0.85, and the pits or recorded marks have a minimum size PL of up to 0.36&lgr;/NA, readout is carried out at a power Pr of at least 0.4 mW for the laser beam. When the laser beam has a wavelength &lgr; of 630 to 670 nm, the objective lens has a numerical aperture NA of 0.60 to 0.65, and the pits or recorded marks have a minimum size PL of up to 0.36&lgr;/NA, readout is carried out at a power Pr of at least 1.0 mW for the laser beam. Pits or recorded marks of a size approximate to the resolution limit determined by diffraction can be read out at a high C/N.

Abstract: The invention provides: an optical recording medium having the changeability and compatibility of media and a large capacity in three dimensions; an optical pickup apparatus for the same and a control apparatus for the same.

Abstract: An optical pickup device for conducting reproducing and/or recording of information in at least two kinds of optical information recording media, comprises a first light source to emit light flux having a first wavelength (&lgr;1) in order to conduct reproducing and/or recording of the information in a first optical information recording medium having a first transparent substrate; a second light source to emit light flux having a second wavelength (&lgr;2) longer than the first wavelength in order to conduct reproducing and/or recording of the information of a second optical information recording medium having a second transparent substrate; a converging optical system for converging the light flux having the first wavelength or the light flux having the second wavelength on the first information recording surface of the first optical information recording medium or on the second information recording surface of the second optical information recording medium; and an optical detector for receiving and detect