Pioneer Electronic Corporation

Pioneer Corporation

Katsumi Kawamura

Hidehiro Ishii

Masami Oishi

Jiro Endo

Takeshi Kohda

Ryuichi Naito

Takao Yamada

Minoru Kosaka

Junichi Nakata

Ichiro Narumi

Kazutaka Mitsuki

Kazuo Yajika

Nobuo Haino

In the case of recording information in a DVD-R 1R as complying with a DVD video standard, which is configured with including at least of a VTS including a VOBS to be reproduced and VTSI and VMGI for controlling the reproduction of one or plural VTSs, the VTS is recorded in the DVD-R 1R. After the VTS is recorded, the tentative VMGI as the tentative control information corresponding to the recorded VTS to form the VMGI after that and to record this VMGI in the DVD-R 1R. Then, the generated tentative VMGI is recorded in the DVD-R 1R every when the VTS is recorded in the DVD-R 1R.

Information recording apparatus, information recording method and information recording medium in which recording controlling program is recorded

Information recording is conducted in the form of the simple format. When the simple format is indicated, the recording control data is not recorded in a lead-in area LIA, and after the information to be recorded is recorded in a data recording area DRA, the recording control data is recorded in a recording manager area RMA and a lead-out area LOA, in the data recording area DRA, recording manager area RMA, lead-in area LIA, and lead-out area LOA, which are predetermined according to the standard format. Further, when the finalizing processing is indicated, by recording again the recording control data according to the standard format to the information recording medium in which the information recording is conducted according to the simple format, the information recording medium which can be applied to the common information recording and reproducing apparatus, is easily realized.

Recording and reproducing method of information regarding medium and information recording and reproducing apparatus

Recording and reproducing method of information recording medium and information recording and reproducing apparatus

Optical disk player with tilt servo including means wherein the transfer frequency characteristic of a feedback circuit for controlling a tilt adjust mechanism is changed to a wide bandwidth transfer characteristic while in a search operation mode, and is changed to a narrow bandwidth transfer characteristic while in a play operation mode. Accordingly, the transfer frequency characteristic of the feedback circuit in the tilt servo system is changed according to the operation mode of the disk player, so that a suitable loop characteristic is selected for the tilt servo system.

Tilt servo device in optical disc player

A focus servo lead-in method is implemented where the focus servo loop is first in an open state. An objective lens located at a position separated by a predetermined distance from the recording surface of a disk is first moved toward the recording surface at a high velocity. At a predetermined time, the moving velocity is decreased to a lower velocity and the focus servo loop is brought to a closed state based on the level of the focus error signal obtained while the objective lens is moving at the lower velocity.

Method and apparatus for leading-in focus servo by moving the objective

A track transverse detection signal generating circuit in a LD or a CD player, which comprises a presence signal amplifier for amplifying a presence signal indicating that an optical spot for reading information exists on a recording track, a controller for receiving a speed signal corresponding to a moving speed of the optical spot for reading information on the recording track to control an amplification level of the presence signal amplifier in response to the moving speed of the optical spot, and a presence signal comparator for receiving the presence signal which has been amplified and transmitted from the presence signal amplifier, for making a comparison between the amplified presence signal and a reference value, and for transmitting a pulse-shaped track transverse detection signal. Therefore, a track transverse detection signal can be reliably generated by raising the gain of the presence signal amplifier or lowering the reference value of the present signal comparator in the case of a track jump operation in which the optical pickup moves at a speed higher than that in the case of an operation of reproducing the optical disk normally and in the case of a high speed accessing operation in which the same moves at a further raised speed.

Track transverse detection signal generating circuit

A pickup driving device for a disk player is provided, wherein the gain of a negative feedback circuit for driving a slider motor is made variable and the gain is changed correspondingly to the operation mode of a disk player, which made it possible to increase the moving speed of a slider motor in a search mode without sacrificing the stability against external disturbances.

Pickup driving device for disk player

A servo system for controlling the position of a reading beam in an optical video disc player or the like in which an offset signal for cancelling an offset in an error signal used for controlling the position of the reading beam is eliminated when the level of the reading signal falls below a predetermined level. Accordingly, erroneous operations such as defocusing and track jumping are prevented when the reading beam crosses scratches, dust, smudges or the like on the recording medium.

Servo system in data reading apparatus

In a system for optically reading out information recorded on a recording medium, the focus servo device includes an object lens supported by a resilient support member and a focus servo loop. The focus loop includes a driving current generating means for generating a driving current of a cylindrical coil of a focus actuator connected to the object lens in accordance with an output signal of a pickup means which includes the object lens. The improvement is that the dc loop gain of the focus servo loop is substantially raised to infinity, so as to reduce the magnitude of the focus error signal which is required to produce the driving current of the cylindrical lens for moving the object lens against the resilient force of the support member. Further, the focus servo device is characterized by a phase retarding circuit for reducing the amount of the phase rotation at the higher frequency range so as to assure the stability of the operation of the focus servo loop.

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Saitama, Japan

Katsumi Kawamura