Abstract: A disc cartridge including a cartridge body having an aperture for exposing a part, of a disc accommodated in it to an exterior environment and a shutter member formed integrally of a slide portion engaged with a groove in a lateral side of the cartridge body for being slidably supported by the cartridge body and a shutter portion for opening or closing the aperture. The shutter member is mounted on the cartridge body for sliding between a first position of closing the aperture and a position of opening the aperture. The shutter member is formed with a tongue extended along a lateral side of the cartridge body so that the lenght of the slide portion in the sliding direction is longer than the length of the shutter portion in the same direction. The shutter member is prevented from being tilted in the sliding direction to assure stable sliding.

Abstract: There is disclosed a mistaken recording inhibiting mechanism employed in a disc cartridge accommodating a disc which permits re-recording of information signals. This mistaken recording inhibiting mechanism comprises a mistaken recording inhibiting member having a pair of resilient arms extended from a closure part and a movement actuating part formed as one with said closure part, said movement actuating part partially facing an aperture formed in a cartridge main body and being adapted for actuating said closure part into movement: from outside the cartridge main body, a slide guide provided within said cartridge main body for guiding said resilient arms of said mistaken recording inhibiting member, and engaging means adapted for being engaged with one of said resilent arms of said mistaken recording inhibiting member and said slide guide.

Abstract: There is provided a disc recording apparatus for recording digital data by an optical unit in such a manner that time compressed digital data are arranged into a plurality of clusters at an interval of a predetermined number of sectors, a cluster-linking sector having a length longer than an interleaving length is provided at each linking part of each cluster, and the digital data are subsequently interleaved and recorded on a disc-shaped recording medium so that interleaving at the time of data recording on the cluster-by-cluster basis is within the range of the cluster-linking sector.

Abstract: A recording and/or reproducing apparatus is disclosed in which informational signals are recorded and/or reproduced by irradiating an optical disc 202 with a light beam from an optical pick-up device 1 through an recording and/or reproducing opening 205 which is formed in a disc cartridge 202 which rotatably houses an optical disc 203. The optical pick-up device 1 which is used for the recording and/or reproducing apparatus comprises a light source and an objective lens 5 for converging the light beam from the light source upon the signal recording area of the optical disc 203. When recording and/or reproducing of informational signal on and/or from the optical disc 203 is performed by the optical pick-up device 1, only the objective lens 5 is moved into the disc cartridge 202 via the recording and/or reproducing opening 205 formed on the disc cartridge 202 to shorten the distance between the objective lens 5 of the optical pick-up device 1 and the disc 203.

Abstract: An optical disk recording and/or reproducing apparatus employing a disk cartridge having accommodated therein an optical disk not more than 80 mm in diameter as a recording medium, the apparatus including an outer casing having a length not larger than 112 mm, a width not more than 89 mm and a height not more than 31 mm which encompasses a cartridge loading section, a driving unit for rotationally driving the optical disk, an optical pickup unit and means for transporting the optical pickup unit across inner and outer peripheries of the optical disk driven rotationally by the disk driving unit for recording information signals on or reproducing information signals from a recording surface on the optical disk, a magnetic head unit for generating an external magnetic field based on information signals to be recorded, the magnetic head unit and the optical pickup unit being connected together for movement in unison therewith and arranged facing each other on opposite sides of the optical disk, controlling means

Abstract: A disc cartridge includes a cartridge main body which accommodates an optical recording medium, such as an optical disc or a magneto-optical disc, and which includes an aperture for exposing the optical recording medium at least partially to outside, a shutter for opening or closing the aperture, a shutter resetting spring for biasing the shutter towards a side closing the aperture and a shutter locking member for maintaining the shutter at a position closing the aperture. A shutter opening/closing member introducing groove having its open end on a side of the cartridge main body normal to the shutter sliding direction is formed along the front side of the cartridge main body parallel to the shutter sliding direction, and the free end of the shutter locking member is exposed partially to the groove to enable the disc cartridge to be loaded to a cartridge loading section of the recording/reproducing apparatus with the shutter sliding direction as the introducing or loading direction.

Abstract: There is provided a disc recording apparatus for recording digital data by an optical unit in such a manner that time compressed digital data are arranged into a plurality of clusters at an interval of a predetermined number of sectors, a cluster-linking sector having a length longer than an interleaving length is provided at each linking part of each cluster, and the digital data are subsequently interleaved and recorded on a disc-shaped recording medium so that interleaving at the time of data recording on the cluster-by-cluster basis is within the range of the cluster-linking sector.

Abstract: A magneto-optical recording apparatus comprising an optical head shiftable in the diametrical direction of a magneto-optical disk and capable of irradiating a light beam onto the magneto-optical disk, and a magnetic head disposed to be mutually opposite to the optical head with the magneto-optical disk interposed therebetween and capable of applying a magnetic field to the magneto-optical disk while being shifted in the diametrical direction of the magneto-optical disk, wherein the magnetic head is shiftable in the diametrical direction of the magneto-optical disk together with the optical head. The magnetic head consists of an E-shaped core and a coil wound around a center core element thereof, and the E-shaped core is so formed that the sectional length of the center core element in one direction extending toward two side core elements becomes equal to or shorter than the sectional length in another direction orthogonal thereto.

Abstract: A magneto-optical disc recording apparatus arranged such that the magneto-optical disc is recorded by irradiating the magneto-optical disc with a recording light beam from an optical pickup head device under the condition that the optical pickup head device is applied with an external magnetic field by external magnetic field generating means. In this magneto-optical disc recording apparatus, a spacer sheet is located on the magneto-optical disc, whereby the external magnetic field is applied to the magneto-optical disc under the condition that the external magnetic field generating means is brought in contact with the spacer sheet.

Abstract: A magneto-optical disc recording apparatus arranged such that the magneto-optical disc is recorded by irradiating the magneto-optical disc with a recording light beam from an optical pickup head device under the condition that the optical pickup head device is applied with an external magnetic field by external magnetic field generating means. In this magneto-optical disc recording apparatus, a spacer sheet is located on the magneto-optical disc, whereby the external magnetic field is applied to the magneto-optical disc under the condition that the external magnetic field generating means is brought in contact with the spacer sheet.