Rohm Co., Ltd.

Soichiro Arimura

Ken Nakahara

Shunsuke Akasaka

Tetsuo Fujii

Koki Sakamoto

Shunsuke Furuse

Two light receiving elements are formed on a support substrate. A first light receiving element is formed of a p-type layer, an n-type layer, a light absorption semiconductor layer, an anode electrode, a cathode electrode, a protection film, etc. A second light receiving element is formed of a p-type layer, an n-type layer, a transmissive film, an anode electrode, a cathode electrode, a protection film, etc. The light absorption semiconductor layer absorbs light in a wavelength range &#x3bb; and disposed closer to the light receiving surface than is the pn junction region. The transmissive film has no light absorption range and disposed closer to the light receiving surface than is the pn junction region. The amount of light in the wavelength range &#x3bb; is measured through computation using a detection signal from the first light receiving element and a detection signal from the second light receiving element.

Optical filter

Photodetection device

A surface emitting laser diode includes a ring-shaped first semiconductor layer including an n-type clad layer, a ring-shaped active layer provided on the first semiconductor layer, and a ring-shaped second semiconductor layer which is provided on the active layer and includes a p-type clad layer and a grating layer including grating units continuously arranged in a circumferential direction, each grating unit including a plurality of regions having different refractive indices and being adjacent to each other in the circumferential direction.

Surface emitting laser diode including grating layer

Growing community of inventors

Kyoto, Japan

Soichiro Arimura