Sharp Kabushiki Kaisha Corporation

Ikuo Nakano

Nobuo Ogata

Sumito Nishioka

Yoshiteru Murakami

Shigemi Maeda

Eiji Yamada

Hiroyuki Tadano

Masaki Yamamoto

Hideharu Tajima

Tetsuya Hayashi

Michinobu Mieda

Go Mori

Yoshihisa Adachi

Hirohisa Yamada

Nobuyuki Takamori

Yasuhiro Harada

Toshihiko Sakai

Tetsuya Okumura

Atsushi Etoh

Osamu Miyazaki

Yoshiro Akagi

Masanori Shimo

Takashi Arimoto

Naomi Asano

Yuichiro Shimizu

In order to realize an accurate electrochemical measurement without a peak caused due to a silver chloride complex ion, an electrochemical measurement electrode of the present invention which measures an electrochemical active substance in a sample solution containing a chloride ion includes (i) a working electrode, (ii) a reference electrode made of silver and silver chloride, and (iii) a silver ion capturing material which captures a silver ion out of a silver chloride complex ion generated in the reference electrode.

Electrochemical measurement electrode, electrochemical measurement electrode chip, and electrochemical measuring method and analysis method using the same

A magnetic recording/reproducing apparatusincludes: a magnetic head; a magnetic recording medium; a spindleand a spindle motor; a suspension arm; a voice coil motor; and a control unit. The control unithas: a motor driver; a head amplifier; a read/write channel; a laser driver; and a controller. The controllerhas: a preliminary recording unit; a judgment unit; an extraction unit; a drive condition determining unit; and a preliminary recording terminating unit. Based on a reproduction signal evaluation value obtained using these units and a predetermined reference value, a drive condition is determined which is suitable for recording onto the magnetic recording medium

Magnetic recording/reproducing apparatus and method for determining magnetic recording condition

An invention disclosed includes a layer number obtaining section () for determining which information storage layer (L) has been accessed and a layer type identifying section () for identifying a type of the information storage layer (L) determined by the layer number obtaining section (). With the configuration, even in a case where an information recording and reproducing apparatus accesses an information storage layer different from an intended information storage layer by false operation or the like, it is still possible to dissolve mismatching between a recording or reproduction control scheme being set up and a recording or reproduction control scheme suitable for the information storage layer thus accessed.

Information recording and reproducing apparatus, program for controlling same, computer-readable storage medium, method for controlling information recording and reproducing apparatus, and information storage medium

According to the present invention, heat generation amount control information for controlling a heat generation amount of a heat generating section () is arranged to correspond to each of temperatures so that a predetermined heat generation amount is obtained at each of the temperatures. The present invention includes a first computing section () that controls the heat generation amount of the heat generating section () according to the heat generation amount control information that is arranged in advance to correspond to temperature information that is obtained from a temperature sensor (). This easily makes it possible to appropriately carry out at least either recording or reproduction with respect to a magnetic recording medium.

Heat generation control device for heat-assisted magnetic recording and reproducing apparatus

There is provided a storage layer () between storage layers (), (). The storage layer () produces a relatively large spherical aberration for a protection layer thickness error. Information is written to or read from the storage layer () with a beam of light having a second wavelength. Information is written to or read from the storage layers (), () with a beam of light having a first wavelength (longer than the second wavelength). Accordingly, a multi-format optical storage medium is realized on which information can be recorded or reproduced with a single objective lens. Also, an optical pickup is realized which is capable of recording or reproducing information on the multi-format optical storage medium.

Multi-format optical storage medium, optical pickup, and optical read/write device

An optical recording/reproducing apparatus is arranged so that, upon recording or reproducing a recording medium having a plurality of recording layers, the gap of the lens groups at the time of forming a converged light spot on this first recording layer is DIS (1), the gap of the lens groups at the time of forming the converged light spot on the N-th layer (the furthest layer from the surface of the recording medium) is DIS (N) and the neutral point of the spherical-aberration correcting mechanism is set at a position satisfying the following expression: lens group gap dst (3)=((DIS (1)+DIS (N))/2.

Optical recording/reproducing apparatus

An optical pickup includes: a first projector for projecting a first light beam of a first wavelength so as to record and reproduce information with respect to an optical disk having a first light transmissive layer; a second projector for projecting a second light beam of a second wavelength longer than the first wavelength so as to record and reproduce information with respect to an optical disk having a second light transmissive layer; an objective lens common to the first and second light beams; and a diffraction optical element made of a lens with a diffraction grating and a refracting face and disposed in an optical path between the first and second projectors and the objective lens. The diffraction optical element is set to satisfy a predetermined equation. As a result, an optical pickup is realized that uses a single focusing means to focus light beams of different wavelengths, so as to record and reproduce information with respect to different kinds of optical disks (recording media) respectively having light transmissive layers of different thicknesses and respectively using different optimum wavelengths of light for reproducing.

Optical pickup

Optical pickup that uses light sources with different wavelengths for each of multiple recording mediums

An aberration detection device which can detect a spherical aberration sensitively by separating a light beam appropriately so as to enlarge a difference in the positions where the respective separated light beams have the minimum spot diameters, and thus to enlarge a deviation amount of the focus positions of the separated light beams, is provided. A hologram for separating a light beam reflected from an optical disk and passing through a dual element objective lens into a first light beam and a second light beam, and a detection device for receiving the first and the second light beams and detecting the deviation of focus positions of the first and the second light beams, are equipped. The light beam directed to the hologram is separated into the first light beam and the second light beam, by a first region and a second region of the hologram which are obtained by being separated at a boundary drawn at an extreme value of a curve representing a wave front when the light beam has a minimum beam diameter on an information recording layer of the optical disk.

Aberration detection device, aberration detection method, and optical pick-up device for controlling spherical aberration

A lens includes a plane surface whose normal direction virtually conforms to an optical axis direction, and a reflecting part is provided on the plane surface to reflect only light within a predetermined waveband. Consequently, inclination of the lens can be detected with high accuracy.

Lens, optical pickup device, and method for detecting lens inclination

An optical recording/reproducing apparatus is arranged so that, upon recording or reproducing a recording medium having a plurality of recording layers, the gap of the lens groups at the time of forming a converged light spot on this first recording layer is DIS(), the gap of the lens groups at the time of forming the converged light spot on the N-th layer (the farthest layer from the surface of the recording medium) is DIS(N) and the neutral point of the spherical-aberration correcting mechanism is set at a position satisfying the following expression: lens group gap dst()=((DIS ()+DIS(N))/2.

Growing community of inventors

Nara, Japan

Ikuo Nakano