Pioneer Corporation

Pioneer Electronic Corporation

Nikkiso Company Limited

Air Water Biodesign Inc.

Ikuya Kikuchi

Takanori Maeda

Ryo Sato

Makoto Sato

Mitsuru Sato

Masakazu Ogasawara

Yoshitsugu Araki

Takayuki Nomoto

Katsuhiro Koike

Atsuya Ito

Ryohei Kagawa

Kiyoshi Tateishi

Junichi Furukawa

Masayuki Iwasaki

Ryuichi Naito

Tomoya Murakami

Kazuo Takahashi

Akari Agata

Yoshihiro Utsumi

Genki Adachi

Sakashi Ohtaki

Hiroshi Nishiwaki

Kagawa Ryohei

A flow velocity determining apparatus () includes an irradiating unit () that emits irradiation light (L) toward a liquid mixture (BL) which contains a non-spherical solid (BC) and a liquid (BP) and flows through a flow path (TB), a detecting unit () that detects reflected light (L) emitted by the irradiating unit () and reflected by the liquid mixture (BL) flowing through the flow path (TB), the detecting unit () being disposed on at least one side of an optical axis (LA) of the reflected light (L) when seen in a plan view of an imaginary plane including an optical axis (LA) of the irradiation light (L) and the optical axis (LA) of the reflected light (L), and a determining unit () that determines a flow velocity of the liquid mixture (BL) by using a light amount of the reflected light (L) detected by the detecting unit ().

Flow velocity determining apparatus

A measuring apparatus is provided with: an irradiator configured to irradiate fluid with light; a first light receiver configured to receive a forward scatter component of scattered light scattered by the fluid; a second light receiver configured to receive a backscatter component of the scattered light; a third light receiver configured to receive a side scatter component of the scattered light; and an outputting device configured to output fluid information about the fluid, which is obtained on the basis of light receiving signals of the first light receiver, the second light receiver, and the third light receiver. According to this measuring apparatus, it is possible to output accurate fluid information because of the use of the forward scatter component, the backscatter component, and the side scatter component of the scattered light.

Apparatus and method for measuring fluid information from light scattering

An optical element includes a first microlens array unit and a second microlens array unit in each of which a plurality of microlenses are arranged. The first and second microlens array units are arranged opposite to each other with a distance which is longer than a focal length of the microlenses arranged in the first microlens array unit. The first microlens unit is arranged on a light-incident side with respect to the second microlens array unit. The interval between the microlenses arranged in the second microlens array unit is narrower than the interval between the microlenses arranged in the first microlens array unit. The optical element can appropriately suppress the occurrence of excessive pixel bright spot.

Optical element, head-up display and light source unit

An optical element includes first and second microlens array units on which microlenses are arranged. The microlenses are formed by lens contour having a polygonal shape in a plan view. The first and second microlens array units are arranged opposite to each other at a position where a distance between the first and second microlens array units is at least longer than a focal distance of the microlens, and are formed so that a direction of vertices of the lens contour of the microlens arranged on the first microlens array unit is different from a direction of vertices of the lens contour of the microlens arranged on the second microlens array unit. According to the above optical element, it is possible to appropriately suppress an influence of shift of the position between the first and second microlens array units, and it becomes possible to produce the optical element with ease.

Optical element, head-up display and method for producing optical element

An optical pickup projects laser beams having the first to the third wavelengths, in response to the type of a recording medium which is an object to which recording or reproduction is to be performed, and reflecting light from the recording medium is received by a light-detecting element. In order to reduce the sizes of the optical pickup, light of the second and the third wavelengths is generated by a single dual-wavelength light source, and reflecting light of all the wavelengths is to be received by the single light-detecting element. A hologram element giving different optical effects to light of each wavelength is arranged between the light irradiating means and the light-detecting element. Thus, appropriate information recording and reproduction can be performed by using light of each wavelength.

Optical pickup

An optical pickup is provided for recording and reproduction of information onto and from an optical disk. In the optical disk, in a forward optical path, a single polarized optical beam is converted to plural polarized optical beams. Polarization modes of the plural polarized optical beams are then converted to a polarization mode suitable for one of the recording and the reproduction to produce polarization-converted optical beams and to radiate the polarization-converted optical beams to the disk. In the backward optical path, polarization modes of the polarization-converted optical beams reflected from the disk are returned to the same polarization mode as that of the plural polarized optical beams, so that plural polarized reflected optical beams are produced. Polarization modes of the plural polarized reflected optical beams are then returned to the same polarization mode as the single polarized optical mode.

An optical pickup apparatus having an irradiation optical system for condensing a light beam on a track of a recording plane and a photodetection optical system for guiding return light to a photodetector to detect a focal error includes a holographic lens provided in the optical path of the return light for outputting 0-th and &#xb1;1st order diffracted lights based on the return light; an optical element provided in front of or behind the holographic lens for providing astigmatism; photodetectors for receiving the 0-th and &#xb1;1st order diffracted lights; and servo-signal generating operation circuits connected to the photodetectors for generating a first and second focus error signals having a first and second capture ranges based on the output signal of the photodetector.

Optical pickup apparatus and focusing control method

A tracking servo apparatus in which reflection light obtained when a laser beam is irradiated onto a recording surface of an optical disc is photoelectrically converted, thereby obtaining a photoelectric conversion signal, a tracking error signal showing a deviation amount of an irradiating position of said laser beam for a track in a disc radial direction on the recording surface is generated by the photoelectric conversion signal, a spherical aberration occurring in an optical system is detected, a level of the tracking error signal is corrected on the basis of the detection result, and the irradiating position of the laser beam is moved in the disc radial direction in accordance with the level-corrected tracking error signal.

Tracking servo apparatus of optical information recording and reproducing apparatus

A phase device for providing a phase difference between an inner radius portion and an outer radius portion of a light beam which is emitted from a light source is provided in an optical path between the light source of an optical pickup apparatus and an objective lens. The light beam to which the phase difference has been provided is converged by the objective lens and irradiated to an optical disc. An interference of an inner radius portion and an outer radius portion of the returning light beam caused when the light beam is diffracted by the optical disc with &#xb1;1 primary diffracted light caused by the diffraction is suppressed. Therefore, an intensity fluctuation of the returning light beam caused by the interference is suppressed. A spherical aberration error showing a thickness error of the optical disc and a focusing error having a high linearity can be detected with high precision on the basis of the returning light. A numerical aperture of the objective lens, consequently, can be increased, high density information recording and information reproduction can be performed, and further, an optical pickup apparatus and an information recording and/or reproducing apparatus each having compatibility are realized.

Optical pickup apparatus and information recording and/or reproducing apparatus

A variable optical unit is provided with at least two phase-shift regions for providing light with phase differences. Phase-shift amount of the phase-shift region is adjusted by the applied voltage in accordance with birefringence of an information medium. A light beam emitted from a light source is incident on the variable optical unit through a collimator lens and a beam splitter. The light beam is polarized in accordance with the aforementioned phase-shift amount of the variable optical unit and converged by an objective lens to radiate the information medium. The reflected light polarized due to the effect of the birefringence of the information medium is polarized again according to the phase-shift amount of the variable optical unit. The reflected light is thereby polarized in the direction in which the beam splitter can reflect the reflected light and then the reflected light reflected by the beam splitter is detected by the condenser lens and an optical detector.

Optical pickup and information recording and/or reproducing apparatus including the same

An aberration correcting device is placed in an optical path extending from a light source of an optical pickup apparatus for irradiating a light beam onto an optical disk to the optical disk. The device includes a pair of light-transmission substrates at least one of which is held freely movable in a way that a major surface thereof moves in a direction vertical to the optical path, and which have complementary curved surfaces facing, and apart from, each other. The curved surfaces are formed in such a manner as to cause the optical path length of a light beam transmitting the pair of light-transmission substrates to be changed by movement of the light-transmission substrates, thus imparting a phase difference to a transmitting light beam, while allowing the phase difference to keep an advancing direction of the light beam thereby to minimize a comatic aberration caused by the optical disk.

Aberration correcting device and optical pickup apparatus using the same

The collision preventing device is used for an optical pickup device for recording or reproducing information to or from an optical information recording medium. The collision preventing device has a shock absorbing layer to prevent a contact of an objective lens and a surface of the recording medium. The shock absorbing layer is laminated on the portion extending from the circumferential edge of the effective-diameter area of the objective lens to the outside edge or to the outside of the objective lens and has a thickness in such a manner that the shock absorbing layer comes in contact with the surface of the recording medium prior to the effective-diameter area, when the objective lens comes close to the surface of the recording medium.

Objective lens collision preventing device and method for manufacturing the same

The present invention relates to an optical multi-layer information recording medium for recording information therein and/or retrieving information therefrom upon radiation of a convergent beam of light. The recording medium includes at least two pairs of recording layer and light-transmissive layer stacked one after another. A first recording layer proximal to a beam radiation side and a second recording layer distal from the beam radiation side are made from a material that satisfies a function including the following parameters; transmissivity and absorptance of the first recording layer, absorptance of the second recording layer, a numerical aperture on the first recording layer, a numerical aperture of the second recording layer, and transmissivity of between the first and second recording layers. Even if the numerical apertures change with spherical aberration compensation made to respective recording layers, a power density of a light spot does not change. Thus, recordation can be performed with consistent recording characteristics.

Optical multi-layer information recordating medium

The present invention relates to an optical pickup having a constant numerical aperture even if spherical aberration is compensated for. The optical pickup is used in an information recording and/or reproducing machine. The information recording and/or reproducing machine records and/or reproduces information in a recording medium upon radiation of a light beam from a light source. The optical pickup includes a condensing optical system for condensing the light beam from the light source onto a recording layer of the recording medium. The condensing optical system includes an object lens. The condensing optical system also includes an aperture positioned about a focal length of the object lens apart from a position of a principal incidence plane of the object lens toward the light source along an optical axis of the condensing optical system.

An information recording at a high density to an information recording medium and a proper reproduction of information which has been recorded on the information recording medium at a high density are realized. Optical characteristics of an information recording medium are measured and information regarding the measured optical characteristics is previously recorded in a proper area on the information recording medium. When an information recording system records information to the information recording medium on which the information regarding the optical characteristics has been recorded, the information regarding the optical characteristics is read and a proper information recording state is adjusted on the basis of the information regarding the optical characteristics, thereby allowing the information recording to be performed. When an information reproducing system reproduces the information from the information recording medium on which the information regarding the optical characteristics has been recorded, the information regarding the optical characteristics is read and a proper information reproducing state is adjusted on the basis of the information regarding the optical characteristics, thereby allowing the information reproduction to be performed.

Growing community of inventors

Tsurugashima, Japan

Ikuya Kikuchi