Mitsumi Electric Company Ltd.

Toyoki Tanaka

Tsukasa Yamada

Takahiko Nishiyama

Soumei Takahashi

Etsuji Hayakawa

Yuji Kimura

Hisamichi Sekine

Hisanori Aga

Riichiro Hibiya

Motoi Komatsu

Somei Takahashi

An image projection apparatus includes a light irradiation device configured to irradiate a laser beam, an optical scan device configured to deflect the laser beam to make an optical scan, and project an image on a display region, an optical sensor arranged outside the display region, and including a first light receiving region and a second light receiving region that are arranged at different positions along a vertical scanning direction of the optical scan, and a deflection angle controller. The deflection angle controller corrects a deflection angle in the vertical scanning direction of the optical scan device, based on a number of times the laser beam is detected by the first light receiving region and a number of times the laser beam is detected by the second light receiving region.

Image projection apparatus and image projection method

A control device for a laser scanning display apparatus includes a laser device, a current source that generates an electric current supplied to the laser device, and a controller that controls the current source to set a current value of the electric current supplied to the laser device. During a period for scanning a non-display area where no image is displayed, the controller sets the current value at a first drive current value that is less than a threshold current value at which the laser device starts oscillating; and during a period for scanning a portion with a luminance level of zero in a display area where an image is displayed, the controller sets the current value at a second drive current value that is greater than or equal to the first drive current value and less than the threshold current value.

Control device, optical scanning device, display apparatus, and control method

A control device, which controls a laser scanning display device, includes a laser device, a first current source that generates a first driving current supplied to the laser device, a second current source that generates a second driving current supplied to the laser device, and a controller. The controller controls the first current source to generate the first driving current having a first set current value that is 1/n times a threshold current value at a time when oscillation of the laser device starts, when scanning a non-display area in which no image is displayed, where n is a number greater than 1. The controller controls the second current source to generate the second driving current having a second set current value that is zero or greater and less than 1&#x2212;1/n times the threshold current value, when scanning the non-display area.

Control device, optical scanner, display device, and control method

An optical scanning control device is provided. The optical scanning control device includes a scanning unit configured to scan light emitted from a laser and a screen on which the light scanned by the scanning unit forms an image. A plurality of micro lenses are arranged in an array on a surface of at least one of a light-entering side and a light-exiting side of the screen. The micro lenses are arranged in an array in such a way that the center-to-center distances are randomized in at least one of a first direction and a second direction orthogonal to the first direction.

Optical scanning control device

A control apparatus is used in a display apparatus. The control apparatus includes a laser element; a temperature sensor configured to detect a temperature of the laser element; a laser driver configured to drive the laser element; and a laser control unit configured to control a driving current to be supplied to the laser element by the laser driver, such that an optical output value of the laser element converges to a target optical output value. The laser control unit determines an initial driving current value that causes an initial optical output value to be output from the laser element, based on temperature characteristic data of the initial driving current value, and a detection temperature of the laser element detected by the temperature sensor, and controls the driving current to start from the determined initial driving current value.

Control apparatus, optical scanning apparatus, display apparatus, and control method

An image projection apparatus includes a light emission unit for emitting laser light; a light scanning unit for projecting an image on a drawing area by reflecting the light and scanning the reflected light; a light detection unit arranged outside of the drawing area; a detection unit for detecting, according to a deviation from a desired value of a first pixel detected by the light detection unit when the light is horizontally scanned in a first direction and a deviation from a desired value of a second pixel detected by the light detection unit when the light is horizontally scanned in a second direction, each of a phase deviation of the laser light in a horizontal scanning direction and a swing angle fluctuation of the light scanning unit; and a compensation unit configured to compensate for each of the phase deviation and the swing angle fluctuation.

Image projection apparatus and compensation method

An optical scanner apparatus that oscillates a mirror to scan incident light, includes an optical scanner unit that includes a sensor that detects an oscillation angle of the mirror, and an interconnect connected to the sensor; and a shading unit that shades the sensor and the interconnect from stray light of the incident light and ambient light.

Optical scanner apparatus

An optical scanner apparatus includes first and second torsion beams which support a mirror support portion supporting a mirror from both sides in an axial direction; first and second horizontal driving beams configured to include first and second horizontal driving sources, respectively, a connecting beam; a first piezo-electric sensor; first and second sensor interconnects connected to one of and the other of an upper electrode and a lower electrode of the first piezo-electric sensor, respectively, the first sensor interconnect and the second sensor interconnect being formed to extend toward the first horizontal driving beam and the second horizontal driving beam, respectively.

Optical scanner apparatus and optical scanner control apparatus

An optical scanning device includes a mirror part including a mirror reflecting surface to reflect incident light, a pair of torsion bars configured to support the mirror part from both sides and configured to form a first axis around which to swing the mirror part by a torsional motion thereof so as to deflect the reflected light, and at least one stress alleviation area configured to alleviate a stress generated by the torsional motion of the torsion bars. The alleviation area is provided between an intersection of a second axis perpendicular to the first axis and passing through the center of the mirror reflecting surface and an edge of the mirror reflecting surface, and at least one of the torsion bars.

Optical scanning device

An optical scanning device includes a mirror part including a mirror reflecting surface to reflect incident light, a pair of torsion bars configured to support the mirror part from both sides and configured to forma first axis around which to swing the mirror part by a torsional motion thereof so as to deflect the reflected light, and at least one stress alleviation area configured to alleviate a stress generated by the torsional motion of the torsion bars. The alleviation area is provided between an intersection of a second axis perpendicular to the first axis and passing through the center of the mirror reflecting surface and an edge of the mirror reflecting surface, and at least one of the torsion bars.

A laminated piezoelectric element includes plural internal electrodes which are laminated and a dead area at outer regions thereof. The laminated piezoelectric element has first and second end surfaces in an expansion direction thereof. In bonding a first bonded surface of a piezoelectric element fixing portion to the first end surface, a bonding method includes forming a first adhesive accumulation in the first bonded surface, accumulating an adhesive agent in the first adhesive accumulation, and bonding the first end surface to the first bonded surface. In bonding a vibration friction element to the second end surface, the bonding method includes forming, in a second bonded surface of the vibration friction element, a positioning guide hole for guiding the second end surface of the laminated piezoelectric element and a second adhesive accumulation, accumulating the adhesive agent in the second adhesive accumulation, and bonding the second end surface to the vibration friction portion.

Bonding method for laminated piezoelectric element

A driving device includes an electro-mechanical transducer having first and second end portions opposite to each other in an expansion/contraction direction, a stationary member coupled to the first end portion of the electro-mechanical transducer, a vibration friction portion mounted to the second end portion of the electro-mechanical transducer, and a moving portion frictionally coupled to the vibration friction portion, whereby moving the moving portion in the expansion/contraction direction of the electro-mechanical transducer. The moving portion is driven by equalizing a constant expanding speed of the electro-mechanical transducer with a constant contracting speed of the electro-mechanical transducer and by setting a constant rest time interval after one of contraction of the electro-mechanical transducer and expansion of the electro-mechanical transducer.

Method of driving a driving device

A position detecting device includes an optical position detecting element and a position information portion which are disposed so as to be opposed to each other. One of the optical position detecting element and the position information portion is mounted on the movable portion while the other thereof is mounted on an internal wall of a cabinet. The position information portion has a pattern where a signal level produced by the optical position detecting element changes in a continuous manner when the movable portion moves in a predetermined direction. The position detecting device carries out position detection of the movable portion in accordance with the signal level.

Position detecting device capable of improving detection accuracy

A driving device includes an electro-mechanical transducer having first and second end portions opposite to each other in an expansion/contraction direction, a stationary member coupled to the first end portion of the electro-mechanical transducer, a vibration friction portion mounted to the second end portion of the electro-mechanical transducer, and a rod-shaped moving portion frictionally coupled to the vibration friction portion, whereby moving the moving portion in the expansion/contraction direction of the electro-mechanical transducer. The stationary member consists essentially of a base alloy which consists of, by weight, 88 to 97% tungsten, 2 to 11% nickel as a binder, and, as the balance, 0.1 to 2% at least one metal having an ionization tendency which is higher than that of tungsten. The stationary member has a surface without nickel plating.

Driving device having suitable stationary member as material

A position detecting device includes an optical position detecting element and a position information portion which are disposed so as to be opposed to each other. The position information portion has a binary pattern where a high light efficient portion and a low light efficient portion are alternately repeated when the movable portion moves in a predetermined direction. The position detecting device includes a loose position detecting portion for detecting a loose position of the movable portion by counting a pulse signal obtained by the optical position detecting element, a close position detecting portion for detecting a close position of the movable portion by counting pulse number of driving pulses which are applied to an electromechanical transducer from a position where the loose position detection is carried out, and a combining arrangement for combining the loose position with the close position to calculate a current position of the movable portion.

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Tokyo, Japan

Toyoki Tanaka