Disk cartridge which has a recess whose height indicates the type of

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 for loading the disk cartridge, a driving unit for rotationally driving the optical disk accommodated in the disk cartridge, 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 accommodated in the disk cartridge, controlling means for controlling a movement of the magnetic head unit perpendicular to the recording surface of the optical disk as a function of the types of the disks accommodated in the disk cartridge loaded into the apparatus, and a disk loading unit for loading the disk cartridge onto the cartridge loading section and loading the optical disk accommodated in the disk cartridge onto the disk driving unit.