Ricoh Company, Ltd.

Shigeru Oohchida

Tsuyoshi Suzudo

Masahiko Nakayama

Hiroyoshi Funato

Hiroshi Akiyama

Junichi Kitabayashi

Toshiyuki Kawasaki

Koji Mori

Shin Aoki

Hideaki Hirai

Yasufumi Yamada

Tetsuya Ogata

Nobuhiro Morita

Masahiro Fujimoto

Suguru Douwaki

A stereo camera apparatus includes a first image capturing unit having first and second lens units, a first light synthesis unit, a first area-divided filter, and a first image capturing element. The first light synthesis unit and the first area-divided filter guide S-polarized and P-polarized light components to the first image capturing element. The second image capturing unit includes third and fourth lens units, a second light synthesis unit, a second area-divided filter, and a second image capturing element. The second light synthesis unit and the second area-divided filter guide S-polarized and P-polarized light components to the second image capturing element. The control unit includes first and second controllers to compute three-dimensional data of object using the S-polarized and P-polarized light component images, respectively.

Stereo camera apparatus and vehicle-mountable monitoring apparatus using same

A tilt sensor for detecting information related to a tilt of an object to a reference plane is disclosed. The tilt sensor includes a diffraction element disposed that diffracts an incident light at diffraction efficiency depending on the incident angle, and a photo detector that detects a diffraction light diffracted by said diffraction element and outputs an photoelectric signal. Since the diffraction efficiency of the diffraction element changes as the incident angle changes, the intensity of the diffraction light from the diffraction element changes. As a result, the photoelectric signal output from the photo detector contains the information related to the tilt of the object.

Tilt sensor using diffraction grating

A diffraction grating with periodically arranged protrusions and grooves at a relatively narrow pitch and improved diffraction efficiency is disclosed. The protrusions of the grating are made of a material whose index of refraction is greater than that of the grooves, and the ratio of the width D of the protrusion to the pitch &#x39b; of the protrusion is set equal to or less than 0.4 (D/&#x39b;&#x2266;0.4).

Diffraction grating, method of fabricating diffraction optical element, optical pickup device, and optical disk drive

A polarization diffraction grating includes two media having different orientation states arranged alternately and cyclically, wherein each boundary between the media forms an oblique rectangular shape.

Diffraction grating, light source unit applying the same therein, and optical head device employing the same

An optical pick-up device for recording/reading an optical recording medium is provided, which can efficiently utilize light emitted from the laser light source. The optical pick-up device includes a light source, an optical system, a quarter-wave plate, a diffraction component, and a photodetector unit. The photodetector unit may further include a transmitting portion for transmitting the light beam emitted from the light source, and may be disposed opposite the light source in a vicinity of the light source so that light emitted from the light source is transmitted through the transmitting portion. The transmitting portion may be an aperture provided in the photodetector unit. Alternatively, the optical pick-up device may further include an optical path separator for separating the diffracted returning light beam from the light beam that passes from the light source to the diffraction component.

Optical pick-up device with convergent light diffraction for recording/reading information on optical recording medium

An optical pickup unit includes a light source of semiconductor laser chips of different light-emission wavelengths; a plurality of holograms placed between the light source and an optical recording medium, the holograms including at least one non-polarization hologram having a substantially uniform diffraction efficiency irrespective of the direction of polarization of incident light and at least one polarization hologram having a diffraction efficiency varying depending on the direction of polarization of incident light; and a wave plate provided between the optical recording medium and the polarization hologram. The returning beam of a light beam emitted from a selected one of the semiconductor laser chips is diffracted by the corresponding one of said holograms to be received by a light-receiving element. The wave plate turns the direction of polarization of the returning beam to a different direction from that of the emitted light beam.

Growing community of inventors

Tokyo, Japan

Shigeru Oohchida