Sanyo Electric Co., Ltd.

Sanyo Optec Design Co., Ltd.

Mitsui Chemicals, Inc.

Yoshiaki Maeno

Atsushi Yamaguchi

Masahiro Higuchi

Masato Yamada

Hitoshi Terasaki

Youichiro Goto

Hiroshi Yamashita

Mitsutaka Yamaguchi

Yoichi Tsuchiya

Shuichi Ichiura

Takashi Arai

Masahiro Sugi

Nobuo Iwatsuki

Takanari Kusafuka

Toru Nose

Hiroyuki Mutou

Yoichiro Goto

Mikio Ichihashi

Yasuhiro Kodama

Tadahiro Miyazaki

Mitsuaki Ogawa

Minoru Ono

A beam irradiation device includes: a laser light source for emitting laser light; an actuator which scans a targeted area with the laser light; a servo optical system which changes a propagating direction of servo light in response to driving of the actuator; a photodetector which receives the servo light to output a signal depending on a light receiving position of the servo light; an actuator controlling section which controls the actuator based on the signal to be outputted from the photodetector; and a laser controlling section which controls the laser light source based on the signal to be outputted from the photodetector. The laser controlling section controls the laser light source to emit the laser light in a pulse manner at a timing when the light receiving position of the servo light coincides with a predetermined targeted position.

Beam irradiation device and laser radar system

A beam irradiation device includes a photodetector which receives servo light and outputs a detection signal depending on a light receiving position of the servo light, and a signal processing section which obtains the light receiving position based on the detection signal. In the above arrangement, the signal processing section has an A/D conversion circuit which converts the detection signal into a digital signal, and an error signal adjusting circuit which converts an error component signal to be outputted from the photodetector when the photodetector is not irradiated by the servo light, into a signal within a processable range of the A/D conversion circuit, and supplies the converted signal to the A/D conversion circuit. A first digital signal derived from the detection signal is corrected with a second digital signal derived from the error component signal.

Beam irradiation device

A beam irradiation device includes a photodetector which receives servo light; a signal processing section which generates a position detection signal based on a detection signal from the photodetector; and a control section which controls the laser light source and the actuator for beam scanning based on the position detection signal. The signal processing section performs a sampling operation with respect to the detection signal from the photodetector at two consecutive sampling timings. The signal processing section includes an A/D converting section which converts a difference between two sampling values obtained by the sampling operation into a digital signal, and a computing section which computes the position detection signal based on the digital signal from the A/D converting section.

A laser beam and a servo beam are incident on a mirror and a transparent member, respectively, so that an angle direction Afrom an optical axis of the laser beam to be incident on the mirror to an incidence plane of the mirror and an angle direction Afrom an optical axis of the servo beam to be incident on the transparent member to an incidence plane of the transparent member are opposite to each other. With such layout of an optical system, scan loci of the servo beam corresponding to respective scan lines become closer to parallel. In the incidence plane and the outgoing plane of the servo beam of the transparent member, fine periodic structures tapered from the incidence plane and the outgoing plane are formed at pitches each equal to or less than a wavelength band of the servo beam. By this periodic structure, reflection of the servo beam on the incidence plane and the outgoing plane is suppressed.

Beam irradiation apparatus

A beam irradiation apparatus includes: an actuator which scans a target region with a laser beam; a photodetector which receives a servo beam and outputs a signal according to a beam reception position; an optical unit which makes the servo beam displaced on the photodetector in association with driving of the actuator; and a position signal generation circuit that generates a signal according to the reception position of the servo beam based on an output signal from the photodetector. The position signal generation circuit has a signal removal circuit that removes a disturbance signal generated when the laser beam is incident on the photodetector, from an output signal of the photodetector.

A laser radar according to an embodiment of the invention includes a beam irradiation head which emits a laser beam and a control circuit which controls the beam irradiation head to perform scan in a two-dimensional direction with the laser beam. In the laser radar, the beam irradiation head includes a laser beam source; a mirror to which the laser beam emitted from the laser beam source is incident; and a driving mechanism which rotates the mirror in first and second directions about a first rotating axis and a second rotating axis perpendicular to the first rotating axis respectively. The control circuit controls the rotation of the mirror in the first direction and the second direction such that a scan region of the laser beam becomes a rectangular shape.

Laser radar and beam irradiation apparatus therefor

A beam irradiation device includes: a first light source for emitting laser light; an actuator for moving a scanning section for receiving the laser light to scan a target area with the laser light; a second light source movable with the scanning section and adapted for emitting diffused light; a light receiving position detecting device for receiving the diffused light to output a signal depending on a position of receiving the diffused light; and a light projecting element, disposed at a position closer to the light receiving position detecting device with respect to an intermediate position between the second light source and the light receiving position detecting device, for projecting an emission position to be defined by the second light source on the light receiving position detecting device via a predetermined projection area.

Beam irradiation device, laser radar system, and detecting device

An optical discincludes a substrate. The substrate is formed by mixing polymethyl methacrylate and a polylactic acid-based resin composition. The polylactic acid-based resin composition contains polylactic acid-based resin in which the content of lactide is reduced to 1,000 ppm or less, and a mold release agent of 0.16 to 0.32 phr. The weight ratio of the polylactic acid-based resin to the polymethyl methacrylate is 70:30 to 50:50.

Optical disc and material for substrate thereof

A light refracting element formed in parallel plate shape is attached to a support shaft of a mirror holder, a semiconductor laser and a PSD are disposed at positions between which the light refracting element is sandwiched. The light refracting element is rotated by rotation of the mirror holder, and whereby a laser beam irradiation position is changed on a light acceptance surface of PSD. The laser beam irradiation position on a light acceptance surface corresponds to the mirror rotation position, so that the mirror rotation position and a laser beam scanning position in a target area can be detected based on an output from the PSD.

A beam irradiation apparatus includes: an optical element which changes a travel direction of a laser beam by being rotated in a predetermined direction; an actuator which rotates the optical element in the direction; a refractive element which is disposed in the actuator and rotates in association with rotation of the optical element; a servo beam source which emits a servo beam to the refractive element; a photodetector which receives the servo beam refracted by the refractive element and outputs a signal according to a position where the servo beam is received; and a power adjustment circuit which adjusts emission power of the servo beam source. The power adjustment circuit adjusts the emission power so that a reception amount of the servo beam in the photodetector becomes constant based on an output signal from the photodetector.

In a beam irradiation device of the present invention, laser beams emitted from a semiconductor laser impinge on an irradiation lens supported by a lens actuator. The laser beams that have passed through the irradiation lens change in outgoing angle in the direction of a y-z plane as the lens actuator is driven. A laser beam scan in the target region is thus performed. A part of the laser beams that have passed through the irradiation lens is reflected and separated by a beam splitter. The separated beams are converged on a PSD through a converging lens. A DSP control circuit monitors a scan position of the laser beams that have passed through the irradiation lens based on a signal from the PSD. When an irradiation position has deviated from a scan trajectory, the DSP control circuit controls an actuator driving circuit to draw the irradiation position back onto the scan trajectory. This beam irradiation device can realize a smooth and stable beam scan operation with a simple construction.

An antireflective member with stability and a low reflectance at low cost may be provided by performing an antireflective treatment to a substrate in a molding process of the substrate. A roughened surface with a continuous pattern in a fine pyramidal shape is formed on a surface of a transparent substrate, the roughened surface is a diffraction surface with zeroth-order diffraction to visible light, and the pattern of the roughened surface is transferred from a mold at a transfer rate of not less than 70%.

Antireflective member and electronic equipment using same

An optical disk includes a first substrate provided with a first minute concaves/convexes forming a CD signal and a second substrate provided with a second minute concaves/convexes forming a DVD signal, and a wavelength selective multi-layered film is formed on the second minute concaves/convexes by laminating titanium dioxide films and silicon dioxide films approximately fifteen (15) layers. Due to the wavelength selective multi-layered film, a laser beam which reproduces the CD signal is transmitted by a transmissivity of more than 80%, and a laser beam which reproduces the DVD signal is reflected by a reflectivity of more than 80%.

Optical disk and method of manufacturing thereof

A display device includes a light guide plate. A light incident on the light guide plate from a linear light source is reflected by a reflecting surface of each of prisms and emitted from a lower surface of the light guide plate. The emitted light is irradiated onto a liquid crystal panel, reflected by a reflecting layer provided within the liquid crystal panel and advances toward a front direction of a screen. Herein, the light guide plate has on its lower surface as an emission surface a number of minute protrusions each having a shape of triangle in vertical cross-section in a manner that the protrusions cover with no space therebetween a whole effective area of the lower surface, and thereby to obtain an antireflection effect.

Light guide plate and display device

In a method of producing a lightguide plate for surface light source according to the present invention, a plate-shaped metal mold for defining the shape of a part of a cavity of a molding die and particularly, the shape of a light emitting surface of the lightguide plate for surface light source (a concavo-convex shape, a lenticular lens shape, etc.) is provided so as to be replaceable, to form a cavity having a desired shape by the replacement of the plate-shaped metal mold. Resin liquid is injected into the cavity, its resin liquid is solidified, and the resin is then released from the cavity. Consequently, a lightguide plate for surface light source having a desired shape and particularly, having its light emitting surface in a desired shape is produced.

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Mizuho, Japan

Yoshiaki Maeno