Denso Corporation

Toyota Jidosha Kabushiki Kaisha

Mirise Technologies Corporation

Qd Laser, Inc.

Kyushu University

Yuki Kamata

Koichi Oyama

Kenichi Nishi

Keizo Takemasa

Yutaka Ohnishi

Toshihiro Oda

Hiroyuki Tarumi

Kiichi Hamamoto

Yutaka Onishi

Haisong Jiang

Hitoshi Yamada

A beam deflection system includes 2M laser light sources configured to emit laser lights, each laser light source being configured to switch two different center wavelengths to each other. The 2M laser light sources are divided into two sets of M types. The laser lights emitted from the two sets of M types of laser light sources are combined and input to a beam deflector. When (i) N is defined as an integer satisfying an expression of '1≤N≤M', and (ii) center wavelengths of Nth laser light sources of the two sets of M laser light sources are defined as λN and λM+N, an expression of “λ1< . . . <λN< . . . <λM<λM+1< . . . <λM+N< . . . <λ2M” is satisfied.

Beam deflection system

An optical semiconductor device includes an active layer having a plurality of quantum dot layers. The plurality of quantum dot layers include: a first quantum dot layer doped with a p-type impurity; and a second quantum dot layer doped with an n-type impurity and having an emission wavelength different from that of the first quantum dot layer.

Optical semiconductor device

An optical transceiver includes a plurality of light sources having a ring resonator, a reception antenna to receive light, and a wavelength-separating filter to separate, from the light received by the reception antenna, light of a same wavelength as the light output from a part of the plurality of light sources. The wavelength-separating filter is composed of the ring resonator included in the light source.

Optical transceiver

In a semiconductor device, a quantum dot group includes a stack of plural quantum dot layers having different central wavelengths at which respective gains are maximum. A part of or all of the quantum dot layers are stacked so that the central wavelengths sequentially shifts along a stacking direction. The quantum dot group includes a longest wavelength layer group composed of some quantum dot layers including a longest wavelength layer having a longest central wavelength and at least one quantum dot layer stacked on the longest wavelength layer. The longest wavelength layer or the longest wavelength layer group has a larger gain at the central wavelength than the gain at the central wavelength of each of the other quantum dot layers.

Semiconductor device

A semiconductor light emitting element includes an optical waveguide having a first and second waveguide provided with a width that allows propagation of light in a second-order mode or higher and a multimode optical interference waveguide provided with a wider width than the first and second waveguide and arranged at a position therebetween. The semiconductor light emitting element further includes a first optical loss layer facing the first waveguide in an active-layer crossing direction for causing a loss of light that is propagating in the first waveguide in the second-order mode or higher and a second optical loss layer facing the second waveguide in an active-layer crossing direction for causing a loss of light that is propagating in the second waveguide in the second-order mode or higher, the active-layer crossing direction being orthogonal to a surface of an active layer.

Semiconductor light emitting element

The semiconductor laser device includes: an activation layer having at least one first quantum dot layer and at least one second quantum dot layer having a longer emission wavelength than the first quantum dot layer. The gain spectrum of the active layer has the maximum values at the first wavelength and the second wavelength longer than the first wavelength corresponding to the emission wavelength of the first quantum dot layer and the emission wavelength of the second quantum dot layer, respectively. The maximum value of the gain spectrum at the first wavelength is defined as the first maximum value, and the maximum value of the gain spectrum at the second wavelength is defined as the second maximum value. The first maximum value is larger than the second maximum value.

Semiconductor laser device

A first optical waveguide is formed on a semiconductor substrate in such a way that the first optical waveguide is surrounded by clad layers. An outside portion of the first optical waveguide is formed as a terminator, which includes a taper portion and a bending structure portion. The taper portion has a width, which is gradually reduced in a direction to a forward end of the first optical waveguide. The taper portion coverts a light confinement condition from a strong condition to a weak condition in the direction to the forward end of the first optical waveguide. The bending structure portion has an arc shape extending from an outside end of the taper portion on a plane parallel to a surface of the semiconductor substrate.

Growing community of inventors

Nisshin, Japan

Yuki Kamata