Olympus Optical Company, Ltd.

Olympus Corporation

Shohei Kobayashi

Junichi Nakano

Satoshi Watanabe

Yasuhiro Miyazaki

Takehiro Yoshida

Koji Matsumoto

Eiichi Sato

Yasuhiro Fujiwara

Takeshi Yamazaki

Akitoshi Toda

Kenichi Ito

Makoto Yoshinaga

Daisuke Matsuo

Terumasa Morita

Chikara Nagano

Kenzi Murakami

Kiyozo Koshiishi

Akihiko Yoshizawa

Hiromu Ikeda

Tsuneo Yanagida

Hiroyuki Imabayashi

Hiroo Okada

Toshihiro Ogata

Nobuo Miyairi

Sadao Shigetomi

Chiaki Sato

Haruhiko Takemura

Nobuyoshi Iwasaki

Syunpei Tanaka

Ikuo Tofukuji

Toshio Tsurukawa

Tasuhiro Miyazaki

Mitunori Kubo

Masato Miyata

In an optical switch, fibers in a fiber array are arranged in a row. When a region where lights input into or output from the fibers in the fiber array intersect is taken as an intersecting position C, and an axis parallel to the fibers in the fiber array and passing through the intersecting position C is taken as a Z axis, then a distance &#x3b4; between a core of a desired fiber among the fibers and an optical axis of a corresponding one of the lenses varies depending on a distance S of the desired fiber from the Z axis.

Optical switch

A spectroscope includes an emitting portion from where light is output, a dispersive element which is disposed on a side of the light emitting portion, to which the light is output, an incidence portion on which, light dispersed by the dispersive element is incident, and a temperature-compensating element which is disposed between the emitting portion and the incidence portion, and which is such that, an angle of incidence of the light dispersed on the incidence portion becomes almost constant with respect to a change in temperature in an operating temperature range. Moreover, the optical apparatus has such spectroscope in which temperature is compensated.

Temperature compensated spectroscope and optical apparatus

A highly reliable optical switch which can output (switch) accurately to an optical fiber for output without being affected by a change in an environment and a change due to an elapsed time is provided. The optical switch includes a first spectroscope which separates spatially light from an optical fiber for input according to a wavelength and a mirror array which includes a plurality of mirrors which reflect separated light and an angle of each of the mirrors can be controlled independently by an electric signal. The optical switch further includes An optical branching device which extracts a part of an output light from the optical fiber for output, an optical fiber for monitoring which guides apart of output light extracted by the optical branching device, a second spectroscope which separates spatially light from the optical fiber for monitoring according to a wavelength, and a photodetector array which can detect lights of different wavelengths separated at the second spectroscope.

An optical switch includes a plurality of light inputting members, a plurality of light outputting members, an optical coupling member which couples light to the light inputting members and the light outputting members, an optical path changing member which changes an optical path from the light inputting members up to the light outputting members, an optical path shielding member which can take a first position which shields collectively all optical paths from the light inputting members up to the light outputting members and a second position which allows light to pass through the optical path, a first driving circuit which drives the optical path changing member, and a second driving circuit which drives the optical path shielding member.

Optical pickup deformable mirror

A laser beam emitted from a laser source provided at a silicon substrate passes through a hologram element formed of a translucent flat plate and a grating, thereby being subjected to NA conversion executed by an NA converting lens, passing through a polarizing film of a polarization beam splitter, and converging onto a magneto-optical disk via a collimator lens and an objective. A part of back-reflection from the magneto-optical disk, which is reflected by a polarizing film of the polarization beam splitter, is reflected by a reflection surface of the splitter, then branched into two polarized light beams by a Wollaston prism, and guided to one light receiving element group. On the other hand, another part of the back-reflection, which passes through the polarization beam splitter, is branched into two beams by the hologram element and guided to the other light receiving element groups.

Optical pickup apparatus

An optical pickup comprises a light source section for emitting a light beam, a floating objective lens for focusing the light beam on an optical disk, a galvano-mirror capable of directing the light beam toward the objective lens and rockable for tracking control, a beam splitter for extracting return light from the optical disk, and a photodetector for detecting return light. The floating objective lens includes a lens for converging the light beam and a slider for holding the lens. The slider is lifted off the optical disk by means of air currents produced as the disk rotates. The galvano-mirror is located adjacent to the objective lens. In other words, the objective lens in a floating state is situated close to the galvano-mirror without intercepting the light beam incident upon the galvano-mirror.

Optical pickup

An optical pickup device comprises a light source, a beam converting optical system for converting a light beam emitted from the light source to a light beam having substantially circular distribution of quantity of light, an objective optical section for converging the light beam on an optical recording medium, and a signal detecting system for reproducing information recorded on the optical recording medium. The signal detecting system includes a separating optical element for separating a return light beam from a go light beam, and an signal detecting section for detecting an information signal based on the separated return light beam. The beam converting optical system has a first beam converting prism and a second beam converting prism, each of which has two optical surfaces nonparallel to each other. One of them is an entrance surface through which a light beam to be converted enters and the other is an exit surface through which the converted light beam exits. Each of the first and second beam converting prisms is arranged so that the entrance surface is oblique with respect to the optical axis and the exit surface is perpendicular to the optical axis.

Optical pickup device

The present invention avoids a loss of information recorded on or information to be recorded onto an optical disk by accepting a state of deterioration of a semiconductor laser in a closed-type optical disk apparatus. The optical disk is rotated in a predetermined direction by a driving of a spindle motor through a motor driver based on an instruction from a control section. Information is recorded onto or reproduced from the optical disk by a semiconductor laser driven through a laser driver based on an instruction from the control section. The state of progress of deterioration of the semiconductor laser is monitored by a monitoring section, and this state is displayed by a light display section according to a deterioration state.

Optical disk apparatus

An optical head for recording and reproducing information on and from an opto-magnetic record medium by projecting a light beam onto the record medium and introducing a return light beam reflected by the record medium onto photodetectors, including a light source for emitting a linearly polarized light beam, an objective lens for projection the light beam onto the record medium, and an optical element having a surface on which a beam splitting surface is provided in the diverging or converging return beam. Said beam splitting surface is curved such that light rays of the return light beam are made incident upon the beam splitting surface at substantially the same incident angle, so that the return light beam can be split accurately into P-polarized and S-polarized light beams.

Optical head having beam splitting surface curved to present a

An optical pick-up apparatus for reproducing information recorded on a magneto-optical record medium including a semiconductor laser emitting a linearly polarized laser beam, and a polarizing film provided between a glass prism and a uniaxial birefringent crystal prism. The laser beam emitted by the semiconductor laser is made incident upon the polarizing film via the glass prism and is reflected thereby. The apparatus further includes an objective lens projecting the laser beam reflected by the polarizing film onto the magneto-optical record medium as a fine spot and converging a return laser beam reflected by the record medium toward the polarizing film. The return beam transmitted through the polarizing film is refracted by the uniaxial birefringent crystal prism and is divided into ordinary light and extraordinary light, which are received by a first photodetector to produce a reproduced information signal. The return beam reflected by the polarizing film is made incident upon a hologram and is diffracted thereby into .+-.1-order beams which are received by a second photodetector to produce a focusing error signal and a tracking error signal.

Optical pick-up apparatus having hologram and beam splitter with

A beam shaping and beam splitting device for converting a cross sectional shape of a polarized parallel incident light beam into a light beam having a corrected cross sectional shape, emanating the light beam toward a reflection surface and emanating a return light beam reflected by said reflection surface in a direction which is different from an incident direction of said incident light beam, including a prism made of an anisotropic material and having a first surface upon which said incident light beam is made incident from an incident direction which is inclined with respect to said first surface and a second surface from which the incident light beam emanates from the prism, in which said return light beam is refracted by said first surface and emanates from the first surface in a direction which is different from said incident direction. A separation angle between the incident light beam direction and the emanating direction of the return beam is mainly determined by a difference in the refractive indices of the prism for ordinary and extraordinary rays and can be made very small. In an optical head including such a beam shaping and beam splitting device, the light source and photodetector can be arranged nearer to each other, so that the optical head can be made small in size.

Beam shaping and beam splitting device and optical head comprising the

The present invention is directed to an apparatus using an integrated type pickup as an optical head for writing and reading optical information and capabling of writing data at high speeds. The apparatus includes a laser diode having an active layer at its intermediate position and having one area side held over a surface of a semiconductor substrate with an insulating layer interposed between the semiconductor substrate and the laser diode relative to the active layer. The laser diode has two areas with the active layer as a boundary and a constant potential is applied from a power supply to the insulating layer side of the laser diode and a transistor (laser diode drive unit) is provided to apply a modulation signal to the other area of the laser diode so that the laser diode is driven to modulate its output. By doing so, a constant potential is maintained at the semiconductor substrate and at the insulating layer's side of the laser diode and the modulation signal is applied to the other area side of the laser diode. When a drive current of the laser diode is varied by the modulation signal, a voltage variation occurs only on the other area side of the laser diode so that a high-frequency drive current, if flowing through the insulating layer side, is small and hence the laser diode has its output to be modulated effectively.

Apparatus using an optical pickup

An optical head has a semiconductor laser for emitting light, a collimator lens for converting the light from the laser into a parallel light beam, a semiconductor substrate for reflecting the light beam, and an objective lens for focussing the light beam reflected from the substrate on the optical disk. A 1/4 wavelength plate is situated between the substrate and the objective lens. A beam splitter which transmits the light from the laser and reflects the light returning from the disk is provided between the collimator lens and the substrate. Following the beam splitter, a collective lens, a cylindrical lens and an optical detector are arranged in this order on an optical path for the returning light. A light receiving element for outputting a signal corresponding to the intensity of the light received is formed on the semiconductor substrate, and a polarizing film is formed on the surface thereof.

Optical head with built-in semiconductor laser, objective lens and 1/4

An optical head for reading and/or writing information from and/or from a magneto-optical record medium including a semiconductor laser, a composite prism having a glass prism, a birefringent prism and a dielectric multilayer film interposed between the glass prism and birefringent prism, an objective lens and fist and second photodetectors. A laser beam emitted by the semiconductor laser impinging upon the glass prims is reflected by the dielectric film and is projected onto the record medium by the objective lens. A return beam reflected by the record medium is incident upon the dielectric film via the objective lens, and a part of the return beam transmitted through the dielectric film is separated by the birefringent prism into a first ordinary beam and a second extraordinary beam which are received by the first and second photodectors, respectively. The glass prism and birefringent prism are made of materials which satisfy a condition that a difference between refractive indices of the birefringent prism for ordinary light and extraordinary light is not less than 0.03 and a difference between a refractive index of the glass prism and at least one of the refractive indices of the birefringent prism is not less than 0.15.

Growing community of inventors

Hachioji, Japan

Shohei Kobayashi