Low operating current and low noise semiconductor laser device for optical disk memories

U.S. Patent Number: 5386429

Abstract: A semiconductor laser device suitable as a light source for an optical disk may be operated at a low operating current with low noise for the 780 nm band. The device comprises: a certain conduction type Ga.sub.1-Y1 Al.sub.Y1 As first light guide layer, a Ga.sub.1-Y2 Al.sub.Y2 As second light guide layer of said certain conduction type, or an In.sub.0.5 Ga.sub.0.5 P or an In.sub.0.5 (GaAl).sub.0.5 P or an InGaAsP second light guide layer, successively formed one upon another at least in one side of the principal plane of an active layer; an opposite conduction type Ga.sub.1-Z Al.sub.Z As current blocking layer formed on the second light guide layer and provided with a stripe-like window; and a Ga.sub.1-Y3 Al.sub.Y3 As cladding layer of the same conduction type as the light guide layers formed on the stripe-like window. The relations of Z>Y3>Y2 and Y1>Y2 define the AlAs mole fractions.

Inventors: Naito; Hiroki (Suita, JP), Kume; Masahiro (Ohtsu, JP), Sugiura; Hideyuki (Takatsuki, JP), Takayama; Toru (Nara, JP), Itoh; Kunio (Uji, JP), Ohta; Issei (Fujiidera, JP), Shimizu; Hirokazu (Suita, JP)

Assignee: Matsushita Electric Industrial Co., Ltd. (Osaka, JP)

Application Number: 08/040,655

Issued: 1995-01-31

Expired: 2007-01-31

Classes: 372/46.01 ; 372/45.01

Field of search: 372/46,45,44

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