Abstract: A compound optical unit includes a housing mounted on an optical pickup apparatus, the housing has a semiconductor laser device, a light receiving device, and a compound optical device, fixed to the housing. The semiconductor laser device includes a laser diode for emitting shorter wavelength laser beams for a DVD and another laser diode for emitting longer wavelength laser beams for a CD. The compound optical device includes an incidence surface and an emission surface for receiving and emitting, respectively, the light beams emitted by the semiconductor laser device, a diffraction lattice provided on the emission surface for diffracting light beams reflected and returned from an optical disk, and a reflective surface for reflecting the light beams diffracted by the diffraction lattice toward the light receiving device. The reflective surface is provided with a correction element for focusing the light beams of different wavelengths on one light receiving position of the light receiving device.

Abstract: When an optical disk is loaded, the light source provided with the optical head for the CD and the light source provided with the optical head for the DVD simultaneously irradiate the laser beams of different wavelengths each toward the optical disk D. And, the optical heads for the CD and DVD are simultaneously driven in parallel in the focusing direction. At that moment, the optical head for the CD and the optical head for the DVD simultaneously detect all the signals added and the RF envelopes individually, which are stored in the memory at the same time. All the signals added and the RF envelopes stored in the memory are sent to the control unit, where a specified processing is carried out to identify the specification of the disk.

Abstract: One major surface of a light guide plate is formed, in stripe form in a plan view, with a plurality of prism grooves each consisting of a slight slope and a steep slope. The inclination angles of the slight slope and the steep slope are in ranges of 1° to 10° and 41° to 45°, respectively. The width of the steep slope in the one major surface of the light guide plate increases as the position goes away from a light incident surface of the light guide plate in such a manner that the width of the steep slope amounts to 1.1 to 1.5 at a position farthest from the light incident surface if it is assumed that the width of the steep slope is equal to 1.0 at a position closest to the light incident surface.

Abstract: A disk drive includes a DVD optical head and a CD optical head. An objective lens in the CD optical head moves along a reference radial line passing through the center of rotation of an optical disk. An objective lens in the DVD optical head moves along a transfer line parallel to the reference radial line, and is disposed so that an expression R0<(Rmin+Rmax)/2 is satisfied, where Rmin and Rmax represent distances along the reference radial line between the center of rotation and the positions of the objective lens when it is disposed on the innermost and outermost tracks of the optical disk, respectively, and R0 represents a distance along the reference radial line between the center of rotation and the position of the objective lens when its tracking correction direction is towards the center of rotation of the optical disk.

Abstract: An optical disk cartridge includes a casing having a pair of walls for accommodating an optical disk therein. In the optical disk cartridge, the walls of the casing are formed with clamping windows for clamping the disk at the central portions thereof, and are formed with reading and writing windows for reading information from the disk and writing information on the disk from the clamping windows to side edges of the casing. A shutter capable of opening and closing the clamping windows and the reading and writing windows is slidably provided. The horizontal size of the clamping windows along a sliding direction of the shutter is formed shorter than the vertical size thereof orthogonal to the sliding direction of the shutter.

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: An optical disk cartridge includes a casing having an accommodating section formed by a pair of top and bottom walls, a discrimination hole formed in one of the walls, a holder accommodated in the accommodating section of the casing and capable of insertion and removal of a disk into and from the accommodating section, an operation element accommodated in the accommodating section, and a breakable blocking part for blocking movement of the operation element and insertion and removal of the holder. In the optical disk cartridge, when the blocking part is broken, the operation element is slidable, and sliding of the operation element allows the discrimination hole to be opened and closed and enables insertion and removal of the holder into and from the accommodating section.

Abstract: An optical disk cartridge includes a casing having an accommodating section, and a holder capable of insertion and removal of a disk into and from the accommodating section while holding the disk. In the optical disk cartridge, the holder is provided with an incorrect-insertion-preventing section for preventing incorrect insertion of the holder into said casing with respect to top and bottom faces thereof.

Abstract: A device for securing an optical element in which, when an opposing surface of a mold for forming a base is formed so that a mounting surface of the base is formed at an angle equal to 90 degrees plus a very small angle, the mounting surface is smoothly formed when the mold is removed from the base. Therefore, it becomes unnecessary to mechanically cut the mounting surface, so that it can serve as a reference surface for directly securing the optical element thereto. This makes it possible to simplify the manufacturing process of the base and to reduce costs.

Abstract: An optical disk cartridge includes a casing accommodating an optical disk therein and having an accommodating section formed by a pair of top and bottom walls, and an operation part slidably accommodated in the accommodating section of the casing. In the optical disk cartridge, the casing is provided with a discrimination hole at position opposing an operating slot, and a closing part at a section thereof other than the discrimination hole opposing the operating slot so that the operation part opens and closes the discrimination hole.

Abstract: An optical disk cartridge includes a casing having an accommodating section formed by a pair of top and bottom walls; and a holder for inserting and removing a disk into and from the accommodating section. The holder has a base part and a pair of elastic arms provided at both ends of the base part to hold the left and right peripheries of the disk. In addition, regulating parts for preventing deformation of the pair of elastic arms toward the disk are provided in the accommodating section of the casing, and the deformation of the elastic arms toward the disk is prevented by the regulating parts.

Abstract: A pair of positioning arms are arranged in a housing, and positioning members are fixed to the positioning arms, respectively. The positioning arms are biased in a direction in which the positioning members become close to each other in response to the elastic force of a biasing member. When a cartridge is inserted, the positioning members are fitted in recessed portions to position the cartridge. When the disk is inserted, the disk is positioned by the positioning members. Both the cartridge and the disk can be positioned by a common positioning mechanism.

Abstract: An error component such as an eccentricity implicated in an encoder itself is superimposed upon a detected value from an FG due to an assembly error of assemblies themselves and in the manufacturing process. As a result, a speed could not be controlled with a high accuracy and wow and flatter could not be reduced. A tape speed (TSS) signal detected and corrected from the tape transport by FG and PG is inputted into a PLL loop within a data controller (TBC) of a reproducing system. A reproduced signal is converted by an A/D converter in response to a reference clock generated therein and this data is temporarily stored in an FIFO. When this data is reconverted by a D/A converter into an analog signal, if this data is sequentially converted at a timing of an absolute control clock of a quartz oscillator, then it is possible to eliminate the error component superimposed upon the head reproduced signal.

Abstract: Since disks of the same type are loaded in a disk device using a conventional disk changer scheme, the disk device is not versatile as a peripheral device of a computer. ROM disks and RAM disks are mixed and stored in a magazine, and this magazine is loaded in the disk device. In the disk device, a tray is identified in step by a detector arranged on the tray to check whether the tray be a ROM disk or a RAM disk. Thereafter, discrimination information is recorded, together with the contents information, on an IC memory arranged on the magazine in step. Thereafter, when the magazine is loaded again, the discrimination information is read from the IC memory, and an operation corresponding to each disk is performed.

Abstract: Light emitted from a light emitting device is reflected by a first reflection curved face so that the travel direction of the light is almost perpendicularly diffused, the light is reflected by a reflection face circumferentially formed on an end face of a rotor in the direction parallel to an axial line, and after that, the light is supplied to a stator side along a cylindrical part on the outer periphery of the rotor. In a stator, light is condensed again in the axial direction by a reflection face and, after that, the light is reflected by a second reflection curved face and is received by a photo sensing device. In this instance, since the light passed through whole slits on the end face of the rotor and whole slits in the peripheral part of the stator is converged and then detected by an FG, the signal level upon detection is increased, the detection accuracy is improved at low cost.

Abstract: A disk device including a guide, formed in a housing, having an inclined guide portion and a straight-line guide portion. A moving member moves along the guide. The moving member is affixed to a wire, and the wire is wound upon a biasing pulley. A small-diameter pulley is formed integrally with the biasing pulley, and a spring is provided at a biasing wire wound upon the small-diameter pulley. When the moving member is pushed into the disk device by a cartridge, the shutter is opened. The moving member is also used to eject the cartridge. Even when the resilient force of the spring is large, the reaction force, produced as a result of cartridge insertion, is small, and the ejection stroke of the cartridge is large. In a conventional disk device for loading a cartridge therein, both a mechanism for opening the shutter of the cartridge, and a mechanism for ejecting the cartridge are required.

Abstract: A plurality of trays (T) are set in a disk package (P) loaded into a disk device, and different types of disks are rested on the trays (T). A first lock mechanism (L1) for locking all of the disks is provided in the package (P) such that this lock mechanism can be manually operated to unlock. A second lock mechanism (L2) locks only the trays on which RAM disks are rested, thereby preventing the RAM disks from being taken out. The disk device comprises unlocking members for releasing the locks established by both locking mechanisms.

Abstract: A disc package loaded in a disc device houses a plurality of trays, and discs of different types are installed on the respective trays. Each tray is provided with a hook and an identification hole indicative of type information of each disc, and an ejector lever for ejecting each tray is provided with a sensor for sensing the information of the identification hole. When the disc package is loaded, the identification of the disc on each tray is known by causing the ejector lever to face sequentially the hooks of the trays.

Abstract: Different types of multiple disks are accommodated in a disk package (P) which is loaded into a disk device. Identification means (20) is provided on a bottom plate (1f) of the case (1) of the disk package (P). This identification means is made up of a jumper card (21) embedded in the case and four bits of identification holes (22a, 22b, 22c, 22d); therefore it can offer 4.times.2 sorts of information depending on whether each of the identification holes is opened or closed. The disk device detects that information and obtains information about the types of the disks in the package.

Abstract: A recording medium driving apparatus employing a compact and high-functionality switching mechanism for loading and unloading a recording medium. The switching mechanism includes a first switching lever movable in a predetermined direction, and a second switching lever whose direction of movement is reversed by an inverting link after moving with the first switching lever in the predetermined direction, the first switching lever includes an arm driving portion for a cartridge and a holder control section for a cartridge holder, and the second switching lever includes a magnetic head control portion. The direction of motion of the second switching lever is reversed when the first switching lever moves so that driving and controlling are shared between both levers.