Abstract: A converter circuit for converting an output voltage from an AC power supply includes a rectifier circuit for rectifying the output voltage of the AC power supply; first and second capacitors connected in series, for smoothing the output of the rectifier circuit; and a switch circuit for switching the connections between the respective capacitors and the AC power supply so that the output voltage of the AC power supply is applied to each of the respective capacitors at a cycle that is shorter than the cycle of the AC power supply.

Abstract: An optical head is provided which is capable of making an optical disk drive unit thinner. The optical head includes: a laser diode which emits light toward an optical disk; a photodiode which is disposed in the same housing as the laser diode; a light-turning mirror which reflects and deflects the light emitted from the laser diode; a light-raising mirror which reflects and deflects the light reflected by the light-turning mirror in the direction of the optical disk; an objective lens that converges the light reflected by the light-raising mirror onto the optical disk; and a hologram element which allows the light reflected by the optical disk to branch off and reach the photodiode, in which at least a part of the light-turning mirror is disposed inside of the window portion of a cartridge which houses the optical disk.

Abstract: An integrated unit in which a light source and a light emitting diode are combined into one component is fixed to an optical bench. Then, relative position adjustment of an objective lens actuator is carried out with respect to the optical bench so that a desired detection signal can be obtained through reflected light from a disk information recording medium and then the objective lens actuator is fixed. The relative position adjustment of the integrated unit is no longer required and it is no longer necessary preliminarily to provide a margin for adjusting the integrated unit. Thus, an optical head can be reduced in size and thickness.

Abstract: A semiconductor laser; a light flux separation element that separates a light flux emitted from the semiconductor laser for a first light flux and a second light flux to come out therefrom; an objective lens on which the first light flux coming out from the light flux separation element is incident to be collected on a optical information recording medium; a light-receiving element on which the second light flux coming out from the light flux separation element is incident; an arithmetic circuit that adjusts a quantity of light emitted from the light source in response to a quantity of light incident on the light-receiving element, are provided. A light exiting-surface of the light flux separation element from which the second light flux comes out is laminated to a light incident-surface of the light-receiving element on which the second light flux is incident via an adhesive layer.

Abstract: A motor driving apparatus includes an inverter circuit for converting an output voltage of a power supply into a three-phase AC and outputting the same to the brushless motor, a rotor position estimation unit for estimating a rotor position of the brushless motor, and an inverter control unit for controlling the inverter circuit so that the brushless motor is driven by a current based on the estimated rotor position. The inverter control unit determines an advance angle of the current supplied to the brushless motor with respect to the estimated rotor position so as to minimize a deviation between a command rpm and an actual rpm. Therefore, it is possible to perform stable weak field control for the brushless motor, independently from the input voltage of the inverter circuit, without using predetermined control variables such as table values.

Abstract: The present invention realizes a compact and thin light-receiving device in a simple configuration, and provides a compact optical head on which this light-receiving device is mounted. The light-receiving device for receiving light reflected from an information recording medium includes a light-receiving chip having a plurality of electrodes and a flexible wiring board on which the light-receiving chip is mounted and fixed. The plurality of electrodes are connected electrically to the flexible wiring board by attaching directly or via a metal wire.

Abstract: A motor driving apparatus for driving a linear vibration motor having a spring member that supports a mover so as to form a spring vibration system including the mover. The motor driving apparatus employs an accurate spring constant of the spring member corresponding to an individual linear vibration motor at a position calculation for obtaining the position of the mover during the operation, thereby increasing the accuracy of the position calculation. The motor driving apparatus includes a mover force vibration unit for making the mover of the linear vibration motor freely vibrate, a relative position detection unit for detecting a timing when the freely vibrating mover passes through a fixed point (relative position), and a natural frequency detection unit for detecting a natural frequency of the mover based on output information from the relative position detection unit, thereby calculating the spring constant based on the detected natural frequency.

Abstract: A motor drive control apparatus for driving and controlling a linear vibration motor having a mover supported by a spring, with an AC current. The motor drive control apparatus includes a waveform creation unit for creating a comparative current waveform to be a reference of a driving current for the linear vibration motor based on the operating condition of the linear vibration motor, a current detector for detecting the driving current, and a controller for controlling a driving voltage of the linear vibration motor so that a difference between the comparative current waveform and a waveform of the current detected by the current detector becomes zero. The frequency of the driving current is controlled to be close to the resonance frequency of the linear vibration motor, based on the comparative current waveform.

Abstract: An inverter control device for driving a motor with small size, light weight and low cost is provided. The inverter control device includes a first motor voltage command corrector that corrects a voltage command of each phase by multiplying the each phase voltage command by a PN voltage correction coefficient, and a second motor voltage command corrector that corrects again the each phase voltage command once corrected by the first motor voltage command corrector, only when any one of the phase voltage commands corrected by the first motor voltage command corrector is larger than the inverter DC voltage, by multiplying the voltage command of each phase corrected by the first motor voltage command corrector by the inverter DC voltage value, and dividing the product of the multiplication by the maximum value of the phase voltage commands corrected by the first motor voltage command corrector.

Abstract: A motor controller (101) according to the invention comprises an inverter circuit (3) for driving a brushless motor (4) and a control unit for controlling the rotational speed of the brushless motor (4) by controlling the phase of the motor current of the brushless motor (4) through the inverter circuit (3).

Abstract: A motor control apparatus includes an inverter circuit for supplying driving power to a motor, a motor current detector for detecting current flowing through the motor, an inverter controller for controlling the inverter circuit based on the output of the detector. The inverter controller has a setting unit for setting various command values to control motor driving status, and a processing unit for controlling the inverter circuit based on the setting on the setting unit. The setting unit sets command value so that a load angle which is an angle between rotor axis and motor applied voltage is operated on the smaller side of the angle that provides the maximum output torque in the load angle-output torque characteristics.

Abstract: An apparatus for driving a motor of a dishwasher includes an AC power source, a rectification circuit for converting an AC power from the AC power source to a DC power, an inverter circuit for converting the DC power from the rectification circuit to an AC power, a motor driven by the inverter circuit to drive a wash pump and/or a drain pump, a current detector for detecting an output current of the inverter circuit, and a controller for performing a PWM (pulse width modulation) control of the inverter circuit based on an output signal of the current detector to thereby control the motor to rotate at a set rotation speed. A phase difference between an output voltage and the output current of the inverter circuit or a reactive current is controlled to have a predetermined value.

Abstract: An optical head and a disk recording and reproducing apparatus using the same. The optical head can realize a stable recording and reproducing with less cross-talk and can be made small and thin by making the objective lens to be small and thin. The optical head includes an optical system including a light source having astigmatic difference and an objective lens that forms an optical spot on an information recording medium. The optical system has optical properties in that the optical spot has an initial astigmatism on the design optical axis, the direction of the initial astigmatism is a direction in which a back-side line focus is substantially perpendicular to the radial direction of the information recording medium, and astigmatism is generated in the direction in which the initial astigmatism of the optical spot is reduced as the objective lens moves in the direction in which the objective lens is more distant from the design optical axis in the radial direction.

Abstract: A light emitting module used for an optical head having a light source and a single or plural light receiving elements and for using record or reproduce information on information recording medium includes a tabular conductive multilayer substrate; and at least a surface mount component mounted on the conductive multilayer substrate; the light emitting module includes at least the light source as the surface mount component.

Abstract: A reflecting mirror and an optical bench are placed on an external jig provided with a mirror holding portion for maintaining the reflecting mirror, and then the reflecting mirror and the optical bench are bonded and fixed, thus obtaining an optical head. An adhesion reference plane for the reflecting mirror is no longer required in the optical bench, thus reducing the size and cost of the optical bench. The mounting precision is high and stable. Further, the reflecting mirror is bonded and fixed at the vicinities of the approximate centers of its two opposed side faces and therefore the variation in orientation of the reflecting mirror due to expansion or contraction of an adhesive is lessened, thus achieving a highly-reliable optical head excellent in environmental stability characteristics.

Abstract: An apparatus for driving a linear vibration motor that employs a proper motor thrust constant value corresponding to each linear vibration motor at position calculation for obtaining the position of the mover of the linear vibration motor, thereby increasing the accuracy of the position calculation. This motor driving apparatus includes a motor driver for applying a DC voltage to the linear vibration motor, and a thrust detection unit for detecting a thrust of the mover, which is generated by the application of the DC voltage to the linear vibration motor, and calculates the thrust constant of the linear vibration motor according to an arithmetic operation of dividing the mover thrust detected by the thrust detection unit, by a value of a DC current that is supplied to the linear vibration motor due to the application of the DC voltage to the linear vibration motor.

Abstract: A driving apparatus of a plasma display panel includes a sustain generator section that sustains sustain electrodes at a specific potential (ground potential) and applies alternately a first positive pulse voltage and a first negative pulse voltage to scan electrodes, as a sustain pulse voltage, during a sustain period, and an address voltage generator that applies a voltage changing temporally to address electrodes. The address voltage generator applies a second pulse voltage with a predetermined polarity to the address electrode in synchronization with a pulse with the same polarity as the second pulse voltage out of sustain pulse voltages during the sustain period.

Abstract: An optical head includes the following: a light beam separator (35) that includes substantial interference regions for light that is reflected from an information recording medium and travels in a straight path and ±first-order diffracted light produced by information tracks of the information recording medium, and diffracts each of plural light beams in regions (32a, 32b) of the substantial interference regions, where the amount of light is changed by a change in the relative angle between the information recording medium and the objective lens and by a shift of the objective lens in the radial direction of the information recording medium; a light-receiving element (36a, 36b) for receiving the light beam that is reflected by the information recording medium and separated by the light beam separator (35); and an arithmetic circuit that corrects a value of an electrical signal detected by the light-receiving element (36a, 36b) in accordance with a radial position signal corresponding to the amount of shift of

Abstract: In a motor control apparatus of the present invention, a control section which receives an input voltage to an inverter circuit, a motor current flowing to a brushless motor and a motor current command value indicating the value of a current required to flow to the inverter circuit, and controls the inverter circuit by maintaining a phase of the voltage applied to the brushless motor when the value of the input voltage to the inverter circuit is smaller than the value of a voltage required to be applied to the brushless motor.

Abstract: A reset pulse generating section applies the total of voltages of a positive voltage source and two constant-voltage sources from a high side ramp wave generating section to a high side scan switching device as the upper limit of a reset voltage pulse, and applies the ground potential from a low side ramp wave generating section to a low side scan switching device as the lower limit of the reset voltage pulse. A sustaining pulse generating section applies the upper and lower limits of a sustaining voltage pulse through a common sustaining pulse transmission path to the low side scan switching device.