Abstract: A carriage servo apparatus according to the present invention comprises: a carriage for supporting a pickup that records or reproduces information relevant to an information recording face; and a carriage motor for moving the carriage in a direction parallel to the information recording face based on a motor drive signal. This carriage servo apparatus further comprises a microcomputer for detecting a minimum value of a motor drive signal required for moving the carriage from its still state, and setting a motor drive signal when recording or reproducing information, based on the detected minimum value.

Abstract: Two sum output signals from two sets of the photodetector elements located symmetrically each other with respect to a light-receiving center of the photodetector of the optical pickup are amplified individually by two amplifiers. A focus error signal is generated in accordance with a difference between respective output levels of the two amplified signals. The gains of the two amplifiers are adjusted in accordance with the focus error signal. A predetermined bias voltage is applied to the focus error signal line in the focus servo control means in accordance with the focus error signal.

Abstract: An information recording medium conveyer is provided, which provides countermeasures against power interruptions with high reliability. When a power interruption occurs during a loading operation with a conveying roller, the first unloading operation is initiated. When the outputs from detection sensors satisfy a predetermined condition during the first unloading operation, the process is initialized to cause the conveying roller to initiate a re-loading operation, thereby loading an information recording medium into a tray. On the other hand, when the outputs from the detection sensors do not change in accordance with a predetermined sequence during the re-loading operation, the process initiates the second unloading operation.

Abstract: There is disclosed an information reproduction apparatus (P) which reproduces music information recorded on a recording medium (DK) wherein the apparatus (P) has a CPU (14) which inhibits reproduction of music information recorded in compressed form based on a preset quality benchmark (e.g., a bit rate) for a sound quality of music information. The information reproduction apparatus (P) may further includes an operation section (15) used to set a quality range indicated by the quality benchmark, on a basis of which music information is inhibited from being reproduced. Using the apparatus, information recorded in a recording medium as a compressed file is reproduced without causing discomfort to a user.

Abstract: A carriage servo apparatus according to the present invention comprises: a carriage for supporting a pickup that records or reproduces information relevant to an information recording face; and a carriage motor for moving the carriage in a direction parallel to the information recording face based on a motor drive signal. This carriage servo apparatus further comprises a microcomputer for detecting a minimum value of a motor drive signal required for moving the carriage from its still state, and setting a motor drive signal when recording or reproducing information, based on the detected minimum value.

Abstract: During an ejecting or unloading operation of an information recording medium by a conveying roller, if detection signals are output from detecting sensors indicating that the object being ejected or unloaded has already been discharged from an insertion hole although it has not, then the insertion hole is closed by the door. If, for some reasons, the door fails to close the insertion hole within a predetermined time, the conveying roller performs a forcible ejecting operation, whereby the object left inside is forcibly ejected to the outside. Thus, ejection or unloading of a medium is carried out without failure.

Abstract: An disk reproducing apparatus (S) for recording information detects an error occurrence inside the disk reproducing apparatus (S) by a system control portion (7). The disk reproducing apparatus (S) obtains at least one of temperature information, voltage information and operational information inside the disk reproducing apparatus (S) on detecting the error occurrence, and records the obtained information onto a memory (8).

Abstract: An information recording medium conveyer is provided, which provides countermeasures against power interruptions with high reliability. When a power interruption occurs during a loading operation with a conveying roller, the first unloading operation is initiated. When the outputs from detection sensors satisfy a predetermined condition during the first unloading operation, the process is initialized to cause the conveying roller to initiate a re-loading operation, thereby loading an information recording medium into a tray. On the other hand, when the outputs from the detection sensors do not change in accordance with a predetermined sequence during the re-loading operation, the process initiates the second unloading operation.

Abstract: During an ejecting or unloading operation of an information recording medium by a conveying roller, if detection signals are output from detecting sensors indicating that the object being ejected or unloaded has already been discharged from an insertion hole although it has not, then the insertion hole is closed by the door. If, for some reasons, the door fails to close the insertion hole within a predetermined time, the conveying roller performs a forcible ejecting operation, whereby the object left inside is forcibly ejected to the outside. Thus, ejection or unloading of a medium is carried out without failure.

Abstract: A liquid-crystal tilt servo apparatus in which a reference voltage generating circuit is unnecessary for a liquid-crystal driving circuit and which has a simple circuit configuration and high reliability is realized. The liquid-crystal driving circuit has a DC removing circuit for removing a DC component of a driving signal generated on the basis of a tilt error correction control signal from a control unit and supplying a resultant signal to a liquid crystal device.

Abstract: A carriage servo apparatus according to the present invention comprises: a carriage for supporting a pickup that records or reproduces information relevant to an information recording face; and a carriage motor for moving the carriage in a direction parallel to the information recording face based on a motor drive signal. This carriage servo apparatus further comprises a microcomputer for detecting a minimum value of a motor drive signal required for moving the carriage from its still state, and setting a motor drive signal when recording or reproducing information, based on the detected minimum value.

Abstract: A focusing bias adjusting apparatus in an optical recording medium playing apparatus, in which a focusing bias adjustment is executed to remove an offset component in a focusing error signal based on each output signal of a split type photodetector in an optical pickup and, thereafter, a tilt adjustment is executed to an optical system so as to maximize a read signal serving as a sum signal of the output signals of the photodetector in order to compensate a tilt angle which is defined by a normal at the irradiating position of a laser beam from the optical pickup on the recording surface of an optical recording medium and the optical axial direction of the laser beam. When the tilt adjusting operation of the optical system of the optical pickup is performed after completion of the focusing bias adjustment, the focusing bias adjustment is executed again.

Abstract: A focusing control apparatus is designed to perform a focus jumping operation successfully. The apparatus has reading device which irradiates read light to a recording medium 1 having information recording surfaces formed on at least two layers, respectively, receiving return light of the read light from the recording medium, and generating a read signal; and control device which executes a focus jumping process to generate a drive signal of a focusing actuator to move an optimum light converging position of the read light from one of the recording surfaces to the other based on a focusing error signal that is generated based on the return light. The apparatus further has drop-out detecting device which detects a drop-out of the read signal and vibration detecting device which detects a vibration of the recording medium or reading device.

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: 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.

Abstract: Disclosed is a focus control apparatus of the present invention capable of successfully performing an accurate focus jump operation without an erroneous operation of a focus actuator. The apparatus irradiates a light beam onto a recording medium, and generates a focus actuator drive signal for moving an optimized light convergence point of the light beam from one recording surface to the other, based on a focus error signal generated based on a returned light from the recording medium.

Abstract: Sensors are provided for detecting brain waves of a user, and a band-pass filter is provided for extracting a particular brain waves including an .alpha. wave included in a detected brain wave. The band-pass filter comprises a first band-pass filter having a narrow pass band, and a second band-pass filter having a wide pass band. One of the first and second band-pass filters is selected, and a stimulation signal is produced in dependency on an .alpha. wave extracted by a selected band-pass filter. In accordance with the stimulation signal, a stimulation light is emitted to the user in order to induce the user to relax or sleeping state.