Abstract: A miniaturized optical disc memory is receivable in a slot, of about 17 mm height, normally accommodating a floppy disc drive. A base includes a base plate with integral, peripheral sidewalls and an internal lateral partition wall which define a cartridge receiving slot on the upper surface of the base plate. First and second support plates extend from the partition wall to the rear peripheral sidewall of the base and define respective, first and second upper mounting surfaces and lower first and second cavities respectively receiving an ejection motor and a fixed optical system, individual optical components being mounted and aligned on integral, precision machined blocks in the second cavity for transmitting a laser beam and receiving a reflected beam along a central, longitudinal optical axis beneath the base plate.

Abstract: A miniaturized optical disc memory is receivable in a slot, of about 17 mm height, normally accommodating a floppy disc drive. A base includes a base plate with integral, peripheral sidewalls and an internal lateral partition wall which define a cartridge receiving slot on the upper surface of the base plate. First and second support plates extend from the partition wall to the rear peripheral sidewall of the base and define respective, first and second upper mounting surfaces and lower first and second cavities respectively receiving an ejection motor and a fixed optical system, individual optical components being mounted and aligned on integral, precision machined blocks in the second cavity for transmitting a laser beam and receiving a reflected beam along a central, longitudinal optical axis beneath the bass plate.

Abstract: A miniaturized optical disc memory is receivable in a slot, of about 17 mm height, normally accommodating a floppy disc drive. A base includes a base plate with integral, peripheral sidewalls and an internal lateral partition wall which define a cartridge receiving slot on the upper surface of the base plate. First and second support plates extend from the partition wall to the rear peripheral sidewall of the base and define respective, first and second upper mounting surfaces and lower first and second cavities respectively receiving an ejection motor and a fixed optical system, individual optical components being mounted and aligned on integral, precision machined blocks in the second cavity for transmitting a laser beam and receiving a reflected beam along a central, longitudinal optical axis beneath the base plate.

Abstract: A disc drive for performing writing information on and/or reading out information from a disc has a head, a movable member, a driving device, a restriction device and a release device. The head writes information on and/or reads out information from the disc. The movable member supports the head. The driving device moves the movable member. The restriction device fixes the movable member in a predetermined position in a moving path of the movable member by using a magnetic attractive force. The release device releases the movable member from the fixed state at the predetermined position by using a magnetic repelling force.

Abstract: A disc storage unit includes a processor for checking whether or not rotation of a disc occurs, head actuator for slightly displacing the head by a predetermined minute amount. At first, the disc is started and then the processor detects presence or absence of rotation of the disc, and the head is displaced slightly in a state in which driving force is applied to the disc by the head actuator.