Kokusai Denshin Denwa Kabushiki Kaisha

Yasuyuki Okamura

Shigeyuki Akiba

Yoshinori Mimura

Chuichi Ota

Yukitoshi Kushiro

Fujio Tanaka

Yoshihisa Komazawa

A semiconductor laser, which comprises a substrate of InP, an active layer, and two clad layers holding therebetween the active layer, and which is constructed so that the refractive index of the active layer may be larger than the refractive indexes of the two clad layers. In one of the two clad layers, the refractive index of a region adjacent to a radiation region in the active layer is larger than the refractive index of a region adjacent to a non-radiation region in the active layer. The refractive index of the other clad layer is equal to the refractive index of that region of said on clad layer adjoining the radiation region or the non-radiation region. The thickness and width of the radiation region of the active layer are selected so that the semiconductor laser may oscillate in the fundamental transverse mode. A buffer layer may be further provided between the active layer and one of the two clad layers.

Semiconductor laser

A single crystal manufacturing device, in which there are provided a crucible having a melting part for holding a molten liquid of a raw material and a nozzle part for continuously taking out a predetermined amount of the molten liquid by the action of gravity; a heater for heating the raw material to melt it in the melting part; and temperature control means for heating the nozzle part to take out the molten liquid of the raw material from the nozzle part and for providing as large a thermal gradient as possible in the solid-liquid interface between the molten liquid taken out from the nozzle part and a grown single crystal continuous to the molten liquid. The crucible can be double-structured. A guide pipe filled with fibrous material may be provided between the nozzle and the rollers of the grown single crystal.

Single crystal manufacturing device

Growing community of inventors

Tokyo, Japan

Yasuyuki Okamura