Pioneer Corporation

Pioneer Electronic Corporation

Pioneer Coorperation

Junichi Furukawa

Kiyoshi Tateishi

Yoshitsugu Araki

Yoshio Sasaki

Noriaki Murao

Hiroshi Nishiwaki

Shoji Fuse

Hideyuki Muto

Takanori Maeda

Masakazu Ogasawara

Hiroki Kuribayashi

Ikuya Kikuchi

Takayuki Nomoto

Mitsuru Sato

Kazuo Takahashi

Sakashi Ootaki

Hiroaki Abe

An information recording apparatus () is provided with: a recording device () for recording information onto an information recording medium () by irradiating the information recording medium with a recording laser beam (L); a controlling device () for recording calibration data onto the information recording medium by using the recording laser beam in which the power is adjusted gradually; and a detecting device () for detecting with a push-pull signal after the recording of the calibration data, the recording of the calibration data being ended if the push-pull signal exceeds a predetermined range, an optimum power of the recording laser beam being determined from a jitter amount included in a reproduction signal.

Information recording device, method, and computer program

An information recording apparatus () is provided with: a recording device () for recording information onto an information recording medium () by irradiating the information recording medium with a recording laser beam (L); a controlling device () for recording calibration data onto the information recording medium by using the recording laser beam in which the power is adjusted gradually; and a detecting device () for detecting degree of modulation of a reproduction signal after the recording of the calibration data, the recording of the calibration data being ended if the degree of modulation exceeds a predetermined range, an optimum power of the recording laser beam being determined from a jitter amount included in a reproduction signal.

Optical disc recording apparatus and method, and computer program

An information recording apparatus () is provided with: a recording device () for recording information onto an information recording medium () by irradiating the information recording medium with a recording laser beam (L); a controlling device () for recording calibration data onto the information recording medium by using the recording laser beam in which the power is adjusted gradually, thereby obtaining the optimum amount of the recording laser beam; and a detecting device () for detecting returned light simultaneously with the recording in the recording of the calibration data, the recording of the calibration data being ended if amount of the returned light exceeds a predetermined range, an optimum power of the recording laser beam being determined from a jitter amount included in a reproduction signal.

Optical disc recording device, method, and computer program

An optical recording/reproducing systemreads a recorded signal written to a recording track of a recording mediumby light. The light is modulated by a drive signal on which a frequency signal is superimposed. The light is scanned along the recording track at a predetermined scan velocity. The optical recording/reproducing systemincludes a computerand an LD driverthat control, based on the scan velocity, a superimposed magnitude of the frequency signal on the drive signal.

Optical recording/reproducing method, system, and program

An optical recording/reproducing systemreads, based on a predetermined reproduction clock, information associated with a recording track of a recording medium by irradiating frequency light. The frequency light is scanned at a predetermined scan velocity. The optical recording/reproducing system includes a computer, a DSP, and a LD driver that modulate light by a drive signal on which a frequency signal is superimposed to thereby output the frequency light, and synchronizes a frequency of the frequency signal with a frequency of the reproduction clock according to the scan velocity.

A data recording/reproducing system () reads a recording signal written on a recording track of a recording medium (), by using light, which is modulated by a drive signal wherein a frequency signal is superposed for scanning the signal along the recording track at a prescribed scanning speed. Then, the system reproduces the read signal as data. The data recording/reproducing system is provided with a computer () for controlling the superposition frequency of the frequency signal for the drive signal corresponding to the scanning speed, and an LD driver ().

A semiconductor laser driving device is mounted on an information recording and reproduction device, and is suitably used for recording and reproducing information. The semiconductor laser driving device includes: a semiconductor laser for emitting a laser light; and a temperature detection unit for detecting a temperature of the semiconductor laser. The semiconductor laser driving device changes the output of the laser light based on the detected temperature. Thus, the semiconductor laser driving unit can suitably improve response characteristics of the semiconductor laser, irrespective of the temperature of the semiconductor laser. Therefore, the semiconductor laser driving device can ensure recording performance onto an optical disc without being affected by the temperature of the semiconductor laser.

Semiconductor laser driving device and semiconductor laser driving method

An optical pickup apparatus comprises a semiconductor laser output controller for emitting laser beam, a photodetector for detecting the emitted laser beam, a sampling processor for performing a sampling process, a pulse current generator for generating erase current pulses, write current pulses, and read current pulses, and a controller for controlling the above components. The apparatus performs the sampling process and generates the current pulses according to a predetermined APC timing and controls the semiconductor laser output controller based on the sampling process and current pulses.

Optical pickup apparatus including emission device, light beam emission control method, and computer-readable recorded medium in which light beam emission control program is recorded

A drive apparatus including: a superposition device which superposes a superposition signal on a drive signal for driving a light beam emission device that emits a light beam and which outputs the drive signal on which the superposition signal is superposed to the light beam emission device, a reference clock signal generation device which generates a reference clock signal, a frequency change device which changes a frequency of the superposition signal based on a quality index for indicating a quality of a reproduction signal that is obtained from a reflection light that is the light beam reflected on a record medium, a phase locked loop device which controls the changed frequency so as to be constant by a feedback method in use of the generated reference clock signal.

Drive apparatus, drive method, information record medium having drive program, and information processing apparatus for drive

An information recording apparatus is provided, which can control over the power of light beams emitted from a light source and various types of servo control with higher accuracy. A laser beam is emitted from a semiconductor laser to write information onto an optical disc. A detection signal indicative of the power of the laser beam output from a light-receiving device is sampled and held with a sample and hold circuit via an I-V converter at a timing delayed by the time corresponding to the delay time of the I-V converter. A tracking error generation circuit and a focus error generation circuit generate a tracking error signal and a focus error signal, respectively, on the basis of a detection signal having information about tracking error and focus error and output from a light-receiving device. Sample and hold circuits sample and hold the tracking error signal and the focus error signal at a timing delayed by the time corresponding to the delay time of each of the generation circuits, respectively. Power control, tracking servo, and focus servo are performed using each of the signals held by the sample and hold circuits, respectively.

Information recording apparatus

An optical pickup apparatus comprises a semiconductor laser output controller for emitting laser beam, a photodetector for detecting the emitted laser beam, a sampling processor for performing a sampling process, an averaging processor for performing an averaging process, a pulse current generator for generating erase current pulses, write current pulses, and read current pulses, and a controllerfor controlling the above components. The apparatus adds averaged values and sampled values and controls the semiconductor laser output controller based on the result of the addition and on the current pulses.

Light beam output control apparatus, optical pickup apparatus, light beam emission control method and computer-readable recorded medium in which light beam emission control program is recorded

A tracking servo apparatus in which reflection light obtained when a laser beam is irradiated onto a recording surface of an optical disc is photoelectrically converted, thereby obtaining a photoelectric conversion signal, a tracking error signal showing a deviation amount of an irradiating position of said laser beam for a track in a disc radial direction on the recording surface is generated by the photoelectric conversion signal, a spherical aberration occurring in an optical system is detected, a level of the tracking error signal is corrected on the basis of the detection result, and the irradiating position of the laser beam is moved in the disc radial direction in accordance with the level-corrected tracking error signal.

Tracking servo apparatus of optical information recording and reproducing apparatus

An optical information reproducing device enables enhancement of information reading accuracy by correcting spherical aberration even if the spherical aberration occurs due to a thickness error in the transparent substrate of an optical disk. The correction amount of the spherical aberration is always changed such that the tracking servo gain in the tracking servo becomes maximum.

Optical information reproducing apparatus

An optical information reproduction apparatus is provided that, even when spherical aberration has occurred because of a thickness error in a transmissive substrate of an optical disk, is capable of improving the information reading accuracy by correcting the spherical aberration. The spherical aberration of an optical system is corrected while changing the amount of correction in a state where an objective lens is retained at a position on a focus adjusting orbit where the amplitude level of a reading signal read from an optical recording medium reaches a maximum. The spherical aberration is then corrected by using the amount of correction, which is defined as the final amount of spherical aberration correction, where the amplitude level of a tracking error signal obtained during this time reaches the maximum.

Optical information reproduction apparatus

A tilt servo control apparatus for an optical disk is provided, which is able to keep a high reproduction quality by correcting tilt errors with its construction simplified and compact. The tilt servo-control apparatus includes: an optical pickup for irradiating an optical beam onto an optical disk and detecting a reflected light from the optical disk; a tilt-correction unit for correcting, using a correction amount, a tilt error due to aberration caused by a tilt angle formed between an optical axis of the optical beam and a normal line of the optical beam at an emitted position on the optical disk; an amplitude detecting unit for detecting a maximum amplitude and a minimum amplitude of a detected signal by the optical pickup within a period of one rotation of the optical disk; and a tilt-correction controlling unit for providing a control signal to control the correction amount used in the tilt-correction unit. The tilt-correction controlling unit includes a unit for applying variations to the control signal and adjusting the control signal so that a difference between the maximum amplitude and the minimum amplitude is minimized responsively to the variations.

Growing community of inventors

Tokorozawa, Japan

Junichi Furukawa