Title:
OPTICAL MODULATOR
Document Type and Number:
Japanese Patent JPH01219717
Kind Code:
A
Abstract:
PURPOSE:To obtain the high-gain optical modulator which has a small spread spectrum and a wide modulation band at the time of modulation by performing n-type doping for the active layer of an LD optical modulator which is made of a semiconductor material and setting the composition wavelength of the active layer on a longer wavelength side than the wavelength of light to be modulated. CONSTITUTION:A semiconductor laser light amplifier is used as the LD optical modulator by modulating an implanted current and the wavelength lambdaS of the light to be modulated is 1.55mum. This optical modulator is constituted by forming an n-InP buffer layer 2, an InGaAsP active layer 3, an InGaAsP attachment back layer 4, and a p-InP clad layer 5 on an n-InP substrate 1 successively by a liquid crystal wavelength method and thus forming a LDH wafer. The band gap wavelength lambdag of this active layer 3 is set to 1.59-1.61mum, preferably, 1.6mum and the n-type doping is carried out by using Te. Thus, the high-gain optical modulator is realized which has the small spread spectrum and wide modulation band at the time of the modulation.
Inventors:
FUJIWARA MASAHIKO
Application Number:
JP4489888A
Publication Date:
September 01, 1989
Filing Date:
February 26, 1988
Export Citation:
Assignee:
NEC CORP
International Classes:
G02F1/025; G02F1/015; (IPC1-7): G02F1/015
Attorney, Agent or Firm:
Uchihara Shin