Sharp Kabushiki Kaisha Corporation

Shigehiro Yamada

Toshiya Nagahama

Naruichi Yokogawa

Kazunori Matsubara

Katsushige Masui

Kazuhiro Tsuchida

Takahide Ishiguro

Koji Yoshifusa

Nobumasa Kaneko

Takashi Itoh

Naotaka Ohtsuka

Yasushi Seike

An optical pick-up apparatus and a semiconductor laser apparatus which can suppress reduction of optical utilization efficiency for the laser light emitted from the semiconductor laser element. When a laser light which is emitted from a laser element for DVD and whose polarization direction is perpendicular to a direction of a groove of the polarization grating is incident on the polarization grating, the polarization grating does not diffract the laser light and transmits the laser light as zero-order diffraction light. Consequently, all of the laser light emitted from the laser element for DVD can be used for reading information signal of DVD and detecting FES and TES. This enables reduction of optical utilization efficiency arising by diffracting action of a grating used for detecting TES of CD in a conventional optical pick-up apparatus to be suppressed.

Optical pick-up apparatus and semiconductor laser apparatus

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.

Semiconductor laser device and method for producing the same

An optical pickup using a holographic optical element includes a light source, a lens system for converting an optical beam outputted from the light source onto a recording carrier, a photodetector for detecting reflected light from the recording carrier and a diffraction grating for introducing the reflected light from the recording carrier to the photodetector in a light path connecting the recording carrier and the light receiving element. The photodetector includes a photodiode and a signal processing circuit which at least amplifies the output signal of the photodiode.

Optical pickup device using a holographic optical element and an

Growing community of inventors

Yamatokooriyama, Japan

Shigehiro Yamada