Nec Corporation

Takayoshi Anan

Naofumi Suzuki

Masayoshi Tsuji

Kenichiro Yashiki

Hiroshi Hatakeyama

Kimiyoshi Fukatsu

Takeshi Akagawa

The present invention provides a surface-emission type semiconductor laser wherein an effective length of a cavity is reduced, thereby enabling to realize a higher-speed direct modulation. In the surface-emission type semiconductor laser according to the present invention, when supposing the optical path length (L) of a resonator part relative to a lasing wavelength &#x3bb;to be given as 0.9&#xd7;&#x3bb;&#x2266;L&#x2266;1.1&#xd7;&#x3bb;, and denoting the refractive indexes of a high refractive index layer and a low refractive index layer of a dielectric DBR by nand n; the average refractive index within an optical path length &#x3bb;/4 in the semiconductor in contact with the dielectric DBR by n; and the refractive indexes of the high refractive index layer and the low refractive index layer of a semiconductor DBR by nand n, respective materials to be used are selected so as to satisfy the following conditions (1) and (2):()()(),&#x2003;&#x2003;(1)

Surface-emission type semiconductor laser

An optical communication system for performing data transmission with optical signals comprises a first optical transmitter and a first optical receiver. The first optical transmitter has a first surface-emitting laser including an active layer of a multiple quantum well structure having a quantum well layer of InGaAs (0.15&#x2266;x&#x2266;0.35), the first surface-emitting laser having an oscillation wavelength ranging from 1000 nm to 1100 nm inclusive. The first optical transmitter transmits an optical signal generated by the first surface-emitting laser. The first optical receiver is connected to the first optical transmitter by a first optical transfer path, and receives the optical signal transmitted from the first optical transmitter through the first optical transfer path.

Optical communication system and optical transmitter

A surface emitting laser is provided with a first multilayer Bragg reflecting mirror including a first layer, a second multilayer Bragg reflecting mirror including a second layer, and an optical resonator unit that is held between these multilayer Bragg reflecting mirrors and includes an active layer. Further, the optical resonator unit contacts with the first layer and second layer respectively. The effective refraction index nof the resonator unit is larger than either the first layer or the second layer, and an optical length nL of the optical resonator unit has a relationship with an oscillating wavelength &#x3bb; of the surface emitting laser to satisfy the following relationship: 0.5&#x3bb;&#x3c;nL&#x2266;0.7&#x3bb;.

Growing community of inventors

Tokyo, Japan

Takayoshi Anan