Abstract: An optical information recording and reproducing device that records information on a recording medium and/or reproduces information on the recording medium, using holography is configured to include a laser light source that performs irradiation with laser light, a first light-shielding portion which is capable of switching between transmission and shielding of laser light emitted from the laser light source, and a driving circuit that drives the switching between transmission and shielding of the first light-shielding portion, and a first movement portion that moves the first light-shielding portion.

Abstract: In a hologram recording/reproducing apparatus where a wavelength-variable laser diode having the external resonator structure is used as its light-source, stable recording/reproducing quality is ensured with respect to a change in the recording/reproducing wavelength against the expansion or contraction of a hologram medium caused by the hologram recording and the temperature change. When the output wavelength from the wavelength-variable laser diode is changed to a predetermined target wavelength, the temperature of the laser light-emission part of the wavelength-variable laser diode is controlled by a temperature control element so that the wavelength band, within which the light-emission power of the laser light-emission spectrum is higher than a predetermined light-emission power, includes the above-described predetermined target wavelength.

Abstract: An optical information recording and reproducing device that records information on a recording medium and/or reproduces information on the recording medium, using holography is configured to include a laser light source that performs irradiation with laser light, a first light-shielding portion which is capable of switching between transmission and shielding of laser light emitted from the laser light source, and a driving circuit that drives the switching between transmission and shielding of the first light-shielding portion, and a first movement portion that moves the first light-shielding portion.

Abstract: In an electrically-operated vehicle including rear wheels on right and left sides of a rear portion of a vehicle body, the electrically-operated vehicle includes a motor that drives the rear wheels, a battery 51 that is arranged above the motor, and a lower battery that is placed between the right and left rear wheels. The lower battery and the motor are arranged in a distributed manner over an axle of the rear wheels between a vehicle front side of the axle of the rear wheels and a vehicle rear side of the axle of the rear wheels. An upper end portion of a rear cushion is supported on a vehicle body frame, and the battery and the motor are supported on a lower end of the rear cushion.

Abstract: According to the present invention, of all beams of light reflected from the optical disc, only light in a peripheral region excluding a push-pull region is used to generate a DPD signal. In this method of signal generation that optimizes internal light-receiving surface interconnections in a photodetector, the lens error signal required for the generation of a tracking error signal in the DPP scheme is amplified at a lower amplification factor. In addition, the light reflected from the multilayered optical disc will be divided into a plurality of regions and the divided beam of light will be focused at different positions on the photodetector. When the beam is focused upon a desired layer, stray light from recording layers other than those to be subjected to information reproduction will not enter the photodetector light-receiving surfaces used for servo signals.

Abstract: There is a need to provide correction of a temperature characteristic of an optical pickup of an optical disk recording/reproducing apparatus, in which items of the optical pickup including spherical aberration may be improved in temperature characteristic. To achieve the need, an optical disk drive is characterized by correcting a spherical aberration correction element when variation of a signal from the control circuit to the driver and/or a tracking or focusing error signal supplied to the controller has a value equal to or more than a predetermined value.

Abstract: Of the beams reflected by an optical disk, only peripheral beams excluding the push-pull region are used to generate a DPD signal in order to optimize internal wire connections among the light receiving areas of the optical detector and thereby reduce the amplification factor of the lens error signal, required for generating the tracking error signal of the DPP method. A beam reflected from a multilayered optical disk is divided into some beam diffraction areas. The divided beam diffraction areas and the light receiving areas are so arranged that the divided beams focus at different positions on the optical detector and that, when a beam is focused on a target recording layer of the disk, stray light from other than the target recording layer being reproduced does not enter into the servo signal light receiving area of the optical detector.

Abstract: In an electrically-operated vehicle including rear wheels on right and left sides of a rear portion of a vehicle body, the electrically-operated vehicle includes a motor that drives the rear wheels, a battery 51 that is arranged above the motor, and a lower battery that is placed between the right and left rear wheels. The lower battery and the motor are arranged in a distributed manner over an axle of the rear wheels between a vehicle front side of the axle of the rear wheels and a vehicle rear side of the axle of the rear wheels. An upper end portion of a rear cushion is supported on a vehicle body frame, and the battery and the motor are supported on a lower end of the rear cushion.

Abstract: According to the present invention, of all beams of light reflected from the optical disc, only light in a peripheral region excluding a push-pull region is used to generate a DPD signal. In this method of signal generation that optimizes internal light-receiving surface interconnections in a photodetector, the lens error signal required for the generation of a tracking error signal in the DPP scheme is amplified at a lower amplification factor. In addition, the light reflected from the multilayered optical disc will be divided into a plurality of regions and the divided beam of light will be focused at different positions on the photodetector. When the beam is focused upon a desired layer, stray light from recording layers other than those to be subjected to information reproduction will not enter the photodetector light-receiving surfaces used for servo signals.

Abstract: Of the beams reflected by an optical disk, only peripheral beams excluding the push-pull region are used to generate a DPD signal in order to optimize internal wire connections among the light receiving areas of the optical detector and thereby reduce the amplification factor of the lens error signal, required for generating the tracking error signal of the DPP method. A beam reflected from a multilayered optical disk is divided into some beam diffraction areas. The divided beam diffraction areas and the light receiving areas are so arranged that the divided beams focus at different positions on the optical detector and that, when a beam is focused on a target recording layer of the disk, stray light from other than the target recording layer being reproduced does not enter into the servo signal light receiving area of the optical detector.

Abstract: A motion vector detector detect a motion vector of each macroblock in an I frame. A control unit controls a quantization unit in such manner that the quantization scale in a quantization table referenced in the quantization processing is adaptively varied for a first macroblock whose motion vector detected is smaller than a prescribed threshold value.

Abstract: There is a need to provide correction of a temperature characteristic of an optical pickup of an optical disk recording/reproducing apparatus, in which items of the optical pickup including spherical aberration may be improved in temperature characteristic. To achieve the need, an optical disk drive is characterized by correcting a spherical aberration correction element when variation of a signal from the control circuit to the driver and/or a tracking or focusing error signal supplied to the controller has a value equal to or more than a predetermined value.

Abstract: A laser driving method and an optical disc recording/reproducing apparatus are provided which are arranged to stably write data on an optical disc. The laser driving method is applied to a laser driving circuit arranged to have a laser diode for emitting a laser beam onto an optical disc, a transistor connected in series with the laser diode and a variable power supply for applying a DC voltage to the laser diode. The laser driving method includes the steps of causing the laser diode to emit a laser beam on trial before starting recording of data on the optical disc, detecting an operating voltage applied onto a contact between the laser diode and the transistor, and adjusting a DC voltage of the variable power supply based on the operating voltage.

Abstract: A driving voltage of a laser diode provided in an optical disc apparatus is properly set based on an operating environment thereof to reduce unnecessary power consumption and heat generation. A temperature detector detects the temperature inside a pickup. A memory stores a value of the voltage to be supplied to a laser driver, the voltage corresponding to each of various operating environments. A controller refers to voltage values stored in the memory to set the voltage to be supplied to the laser driver based on a current operating environment. Operating environment parameters includes at least one of the temperature, operation mode, recording rate, and accumulated light emission time. The voltage value to be stored in the memory is a value of the voltage at which electric power consumed by the laser driver becomes smallest in the operating environment.

Abstract: The present invention provides an optical disc device and a method for focus control which enable an efficient operation for focusing without giving damages to an optical disc. A focus control section detects a focus position (drive voltage V1) by shifting an objective lens in the state where the optical disc is stopped (first step). Then, an amplitude (V2) of vertical deviation of the optical disc is detected from a reflected optical signal from the optical disc obtained by giving minute wobbling to the objective lens in the state where the optical disc rotates (second step). Based on the detected amplitude of vertical deviation of the optical disc, limit values (V3) are set for preventing collision between the objective lens and the optical disc. Then focusing is performed within a range defined by the limit values (third step).

Abstract: A remote control system which is suitable for selective execution of any one of a plurality of functions of an automatic answering telephone apparatus by means of remote control over a telephone line. In the system, questioning speeches corresponding to the individual functions respectively are sequentially transmitted to the user of the apparatus, and the answer of the user to a specific question is detected to execute the specific function.