Sharp Kabushiki Kaisha Corporation

Kazuhiro Tsuchida

Katsushige Masui

Tetsuo Ueyama

Keiji Sakai

Kazunori Matsubara

Toshiya Nagahama

Yukio Watanabe

Shinzoh Murakami

Osamu Miyazaki

Masahiro Ikehara

Shin Itoh

Takahide Ishiguro

Naotaka Otsuka

Shigehiro Yamada

Tohru Murata

Naotaka Ohtsuka

Image capturing accuracy is improved while a simple optical system is used. An image capture device includes: a polarizing filter that blocks non-transmitted light that has been in polarized light of an infrared ray radiated from a light source and has not been transmitted through an image capturing target and transmitted light that has been in the polarized light and has been transmitted through the image capturing target without diffusion inside the image capturing target, and transmits transmitted light that has been in the polarized light and has been diffused inside the image capturing target and transmitted therethrough; and an image sensor that receives the light that has been transmitted through the polarizing filter and captures an image of the image capturing target.

Image capture device and biometric authentication device

There is provided an optical pickup apparatus that can obtain a stable servo signal by reducing stray light generated by diffraction in a recording layer other than a recording layer on which light is condensed. A hologram element provided in an optical pickup apparatus for recording information onto a recording medium and/or reproducing information on the recording medium by use of light includes fourth and fifth divisions where at least first-order diffracted light among diffracted light beams obtained by reflection and diffraction on a recording layer other than a light-condensed recording layer on which light is condensed by an objective lens so as not to be directed toward first and second light-receiving elements for detecting focus position information and third to eighth light-receiving elements for detecting track position information.

Optical pickup apparatus

An object of the invention is to provide a splitter, a light emitter, and an optical pickup apparatus which can realize a stable track servo. Because of the structure of an optical system including an objective lens () and a hologram pattern (), even when the hologram pattern () is irradiated with a reflected light from one recording layer other than another recording layer in a focused state, first and second TES splitting portions () are not irradiated with the reflected light from the one recording layer, but the reflected light is led to an axis vicinity portion () only. Accordingly, light reception by first and second TES light receiving portions () is prevented, accurate track position information and deviation information can be positively acquired, and troubles such as the objective lens () being driven beyond a movable range can be eliminated.

Splitting element, light emitter, and optical pickup apparatus

An optical pickup includes a hologram element. The hologram element is provided with a hologram pattern including a splitting section for focus which splits light used for the detection of an FES and a splitting section for tracking which splits light used for the detection of a TES. The splitting section for tracking is formed in a region excluding a region interposed between a first virtual straight line and a second virtual straight line. The first virtual straight line is drawn on the hologram element in parallel to an X direction and passes through an optical axis of reflected light entering the hologram element in a state where the objective lens is in a neutral position, and the second virtual straight line is drawn in parallel to the first virtual straight line, while being spaced at a distance d from the first virtual straight line.

Optical pickup

To read information from a target information recording surface reliably by canceling DC offsets in tracking-signal detection signals is provided. In effecting tracking servo by 3-beam method, auxiliary light receiving domains D, D, D, Dare provided. The auxiliary light receiving domain receives images formed by the light returned from a different information recording surface from the one targeted for reading. Sub beams of &#xb1; first-order diffracted light enter the light receiving domains D, D, D, D. With respect to the diffraction direction of the hologram, the auxiliary light receiving domains D, D(D, D) are provided on both sides of the light receiving domain D(D). Since signals are computed as: D&#x2212;(D+D); and D&#x2212;(D+D) with the internal connection, DC offsets can be canceled in RES signals (D+D, D+D) used in the DPP method.

Optical pickup device using polarizing hologram element and hologram laser therefor

In this semiconductor laser device, a polarization hologram transmits an outgoing beam directed from a semiconductor laser chip to an optical disk as a forward beam without diffracting the beam, and diffracts a backward beam of the laser beam, which is a return beam of the forward beam that has been reflected by the optical disk, so that the backward beam is deflected from a direction directed toward the semiconductor laser chip part and further directed toward first, second photoreception parts. Therefore, optical loss on the forward way from the semiconductor laser chip to the optical disk can be reduced, and return light to the semiconductor laser chip can be suppressed, so that a high-power, high-sensitivity semiconductor laser device can be realized.

Semiconductor laser device and optical pickup device

It is an object of the invention to provide a holographic laser and an optical pickup, with which it is possible to read from and write to a plurality of types of optical disks with different read wavelengths, and to achieve a more compact apparatus. The holographic laser includes for example a package, two semiconductor laser elements and a photodiode for reading out signals accommodated within the package, a holographic element positioned proximate to or in close contact with the top of a glass window, and a wavelength separating element positioned proximate to or in close contact with the top of the holographic element. The holographic laser is integrally formed as a single component.

Holographic laser and optical pickup

Not only a semiconductor laser element and a photodetector but also a capacitor connected to the photodetector is housed in a package to thereby reduce the distance from the capacitor to the photodetector so that power source noise is efficiently suppressed by the capacitor and a power source noise suppression effect is improved.

Growing community of inventors

Higashihiroshima, Japan

Kazuhiro Tsuchida