Abstract: An information recording medium reproducing system has an insertion opening, a recording medium storing portion and a medium carrying device. Photodetectors are provided for detecting passing of the recording medium and for producing a passing signal when the medium passes. A controller is provided for controlling operation of the medium carrying device. The controller applies a discharge signal to the medium carrying device when the passing signal is not produced within a predetermined time, whereby the medium carrying device is actuated in discharge operation.

Abstract: An optical disk playing apparatus which performs at least a focusing servo operation for reading light as a servo operation and irradiates the reading light onto one optical disk, receives reflected light from the optical disk by a pickup to obtains a light receiving signal, moves an irradiated position of the reading light onto the optical disk to cross tracks on the disk; generates a tracking error signal in response to the reading signal during the track crossing; compares the tracking error signal with a threshold value; and determines the type of the optical disk in accordance with the number of pulses in the compared result signal within a predetermined period from start of the track crossing.

Abstract: An information recording medium reproducing system has an insertion opening, a recording medium storing portion and a medium carrying device. Photodetectors are provided for detecting passing of the recording medium and for producing a passing signal when the medium passes. A controller is provided for controlling operation of the medium carrying device. The controller applies a discharge signal to the medium carrying device when the passing signal is not produced within a predetermined time, whereby the medium carrying device is actuated in discharge operation.

Abstract: An information recording medium reproducing system has an insertion opening, a recording medium storing portion and a medium carrying device. Photodetectors are provided for detecting passing of the recording medium and for producing a passing signal when the medium passes. A controller is provided for controlling operation of the medium carrying device. The controller applies a discharge signal to the medium carrying device when the passing signal is not produced within a predetermined time, whereby the medium carrying device is actuated in discharge operation.

Abstract: An information recording medium reproducing system has an insertion opening, a recording medium storing portion and a medium carrying device. Photodetectors are provided for detecting passing of the recording medium and for producing a passing signal when the medium passes. A controller is provided for controlling operation of the medium carrying device. The controller applies a discharge signal to the medium carrying device when the passing signal is not produced within a predetermined time, whereby the medium carrying device is actuated in discharge operation.

Abstract: An apparatus for detecting the absence or the presence of the occurrence of the abnormal insertion that a plurality of disc bodies each of which should be inserted separately one by one are inserted consecutively, provided with: a passing detecting device for detecting the passing of the disc body, mounted on the passing route of the disc body, and a determining device for determining the occurrence of the abnormal insertion if the detecting device detects the passing again after the detecting device detected the passing once.

Abstract: A first detector is provided for detecting an optical disc inserted in an opening of a reproducing system and for producing a first signal, and a second detector is provided on a reproducing device for detecting the disc carried to the device and for producing a second signal. A sensing circuit is provided for sensing a temporary reduction of a voltage of power supplied to the system and for producing a temporary reduction signal. A control means is provided to be responsive to the first signal and to the temporary reduction signal for operating a carrying device to carry the disc in an unloading direction, and in a loading direction when the disc reaches a predetermined position.

Abstract: An optical disk playing apparatus which performs at least a focusing servo operation for reading light as a servo operation and irradiates the reading light onto one optical disk, receives reflected light from the optical disk by a pickup to obtains a light receiving signal, moves an irradiated position of the reading light onto the optical disk to cross tracks on the disk; generates a tracking error signal in response to the reading signal during the track crossing; compares the tracking error signal with a threshold value; and determines the type of the optical disk in accordance with the number of pulses in the compared result signal within a predetermined period from start of the track crossing.

Abstract: A disc reproducing apparatus is provided which is adapted to scan information tracks to read information recorded on an information recording medium. This disc reproducing apparatus comprises: determining means capable of determining an actually happened track jump, said determining being effected when a difference between a present reproducing positional information and a reference reproducing positional information is larger than a predetermined value; detecting means for detecting a present track position which is just being reproduced at a present time; and setting means for setting said predetermined value corresponding to the present track position, in accordance with a result of the detecting means.

Abstract: A system for reproducing recording mediums has a reproducing device, a storing device for storing a plurality of recording mediums, a moving device for relatively moving the reproducing device and storing device for reproducing a recording medium. A controller is provided to be responsive to a command for operating the moving device for positioning the reproducing device and the storing device at predetermined fixable initializing positions.

Abstract: A focus control apparatus for a multilayer optical recording medium performs an adequate focus jump on a multilayer optical recording medium. Threshold values are set according to the amount of a level change in a focus error signal of a loaded multilayer optical recording medium, and focus jump control is conducted based on the result of comparison between the level of the focus error signal and the set threshold values.

Abstract: A focus control apparatus for a multilayer optical recording medium which performs an appropriate focus jump on a multilayer optical recording medium. This focus control apparatus implements such focus jump control as to temporarily release a focus servo on one layer of a loaded multilayer optical recording medium, shift the focus position of read light on another target layer and then restart the focus servo on the another target layer, detects an ambient temperature, sets a drive signal condition according to the temperature detection output, and moves the focus position of the read light under the set drive signal condition.

Abstract: A carriage controller for a multi-layer disc which is capable of performing a stable carriage control during reproduction of a multi-layer disc of the opposite recording scheme. A tracking error signal is relayed by an equalizer, and a carriage motor is driven in accordance with an output signal of the equalizer. An information reading direction on a layer of a disc on which a pickup reads information is detected, and an equalizer characteristic is set in the equalizer in accordance with the detection result.

Abstract: Apparatus and method for focus control are devised to cope with a fluctuation of an optimum gain of a focus servo loop due to a difference between light reflectance of recording surfaces or the like and to allow an optimum focal position of read light to preferably trace a target recording surface.