Sony Corporation

Shoji Hirata

Tsunenori Asatsuma

Yoshiro Takiguchi

Keigo Aga

Hironobu Narui

Koji Iwamoto

Hiroki Nagasaki

Shiro Uchida

Yoshifumi Mori

Koshi Tamamura

Kazuo Honda

Takayuki Kawasumi

Masafumi Ozawa

Kazutoshi Nomoto

Hiroshi Yoshimatsu

Tsuyoshi Nagatake

Seiji Ijuin

Tsuyoshi Tojyo

Atsushi Ogasawara

Hironobu Harui

Shoichiro Matsunaga

A laser diode which realizes NFP with a stable and uniform shape. The laser diode includes, on a semiconductor substrate, an active layer, one or a plurality of strip-shaped current confinement structures confining a current which is injected into the active layer, and a stacked structure including one or a plurality of strip-shaped convex portions extending in an extending direction of the current confinement structure.

Laser diode and method of manufacturing the same

Provided is a laser diode which realizes NFP with a stable and uniform shape. The laser diode includes, on a semiconductor substrate, an active layer, one or a plurality of strip-shaped current confinement structures confining a current which is injected into the active layer, and a stacked structure including one or a plurality of strip-shaped convex portions extending in an extending direction of the current confinement structure.

A laser diode capable of effectively inhibiting effects of feedback light is provided. A laser diode includes a substrate, and a laminated structure including a first conductive semiconductor layer, an active layer having a light emitting region, and a second conductive semiconductor layer having a projecting part on the surface thereof, on the substrate, wherein a feedback light inhibition part is provided on a main-emitting-side end face, and effects of feedback light in the vicinity of lateral boundaries of the light emitting region are inhibited by the feedback light inhibition part.

Laser diode

This semiconductor laser device has the same structure as the conventional broad-area type semiconductor laser device, except that both side regions of light emission areas of active and clad layers are two-dimensional-photonic-crystallized. The two-dimensional photonic crystal formed on both side regions of the light emission area is the crystal having the property that 780 nm laser light cannot be wave-guided in a resonator direction parallel to a striped ridge within the region. The light traveling in the direction can exist only in the light emission area sandwiched between two photonic crystal regions, which results in the light laterally confined by the photonic crystal region. The optical confinement of the region suppresses the loss in the light at both edges of the stripe serving as the boundary of the optical confinement, which reduces the curve of wave surface and uniforms the light intensity distributions of NFP and FFP.

Semiconductro laser device

A vibration detection device that includes a light source that emits a laser beam; an interferometer, which includes two vibrating bodies that are capable of reflecting the laser beam, that splits the laser beam to cause interference patterns; and a detector that detects vibrations on the basis of the interference patterns.

Vibration detection device and vibration detector

A laser beam multiplexer capable of easily multiplexing a plurality of laser beams is provided. A laser beam multiplexer includes a multiplexing element having a hollow portion with a sectional elliptical shape, in which the multiplexing element includes: a plurality of light-incident apertures guiding laser beams from outside toward one of two focal points of the hollow portion, a reflective layer arranged on a wall surface of the hollow portion, and multiplexing a plurality of incident laser beams while reflecting the plurality of laser beams, and a light-emitting aperture guiding laser beams multiplexed by the reflective layer toward outside.

Laser beam multiplexer

A laser diode device capable of obtaining high light efficiency and improving output by using an AlGaInN compound semiconductor as a material is provided. The laser diode device includes semiconductor layer which has an active layer and is made of a nitride Group III-V compound semiconductor containing at least one of aluminum (Al), gallium (Ga), and indium (In) among Group 3B elements and nitrogen (N) among Group 5B elements. The active layer has a strip-shaped light emitting region whose width W is from 5 &#x3bc;m to 30 &#x3bc;m, length L is from 300 &#x3bc;m to 800 &#x3bc;m, and output of laser light from the active layer is 200 mW or more.

Laser diode device

A laser diode capable of effectively inhibiting effects of return light is provided. A laser diode includes a substrate, and a laminated structure including a first conductive semiconductor layer, an active layer having a light emitting region, and a second conductive semiconductor layer having a projecting part on the surface thereof, on the substrate, wherein a return light inhibition part is provided on a main-emitting-side end face, and effects of return light in the vicinity of lateral boundaries of the light emitting region are inhibited by the return light inhibition part.

Semiconductor laser device

Semiconductor laser device with multi-dimensional-photonic-crystallized region

A semiconductor laser device is one of AlGaInAs semiconductor laser devices, and has a multi-layer structure with a n-GaAs substrate on which a n-AlGaAs buffer layer, a n-AlGaAs clad layer, active layer portion, p-AlGaAs clad layer and p-GaAs cap layer are formed. The active layer portion is configured as a multi-layer structure including (AlGa)InAs light guide layer, AlGaAs active layer and (AlGa)InAs light guide layer. By using the AlGaInAs layer to which In is added is used as the light guide layers, the active layer is under compressive strain. Accordingly, the lattice constant of the active layer at the laser emitting edge becomes smaller due to a force from the adjacent light guide layers. The band gap energy of the active layer near the laser emitting edge becomes larger than the inside of laser device, thereby forming the window structure.

The present invention provides a semiconductor laser including a plurality of light emission portions provided on the same substrate, each of which is adapted to emit laser beams with a multi-mode. A part of the plurality of light emission portions constitute a main light emission group, and the rest of the plurality of light emission portions constitute a sub-light emission group. A main electrode for supplying a current to the main light emission group and a sub-electrode for supplying a current to the sub-light emission group are separately provided. With this configuration, it is possible to keep the entire quality of laser beams of the semiconductor laser constant.

Semiconductor laser

A method of fabricating a semiconductor light-emitting device in which the window structure can readily be obtained without relying upon an advanced process technology. In the method of the present invention, a first multi-layered film formed on a substrate is patterned into a groove pattern having a widened portion and narrowed portions provided on both sides of such widened portion. A second multi-layered film is then epitaxially grown on the substrate so as to cover the groove pattern, by successively growing an n-type second lower clad layer, a second active layer, a p-type second upper clad layer and a p-type cap layer. The cap layer is then patterned to thereby form a current injection layer on the second multi-layered film within the groove pattern so as to be extended along the longitudinal direction of such groove pattern.

Method of fabricating a semiconductor light-emitting device and the semiconductor light-emitting device

A semiconductor laser driving method, which is usable in an optical disc apparatus, for example, makes it possible to use a semiconductor laser in a low noise condition when the semiconductor laser is RF-modulated, by driving the semiconductor laser under a conditions where the average optical output is offset from peaks appearing in a curve representing the relative intensity of noise to average optical output characteristics of the semiconductor laser. More specifically, RF modulating conditions (frequency, amplitude and waveform) are selected so that the peaks do not enter the range of P*&plusmn;0.5 mW relative to the practically used average optical output P*, for example.

Growing community of inventors

Kanagawa, Japan

Shoji Hirata