The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 02, 2009
Filed:
Nov. 09, 2007
Hiroshi Inenaga, Hitachinaka, JP;
Junshin Sakamoto, Hitachinaka, JP;
Hiroshi Inenaga, Hitachinaka, JP;
Junshin Sakamoto, Hitachinaka, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A semiconductor laser device including an edge-emitting type laser chip having at least three emitting points in one light emitting edge, a sub-mount mounted with the laser chip, and a heat sink bonded to the sub-mount through a solder layer. When R designates a linear expansion coefficient ratio of the heat sink to the sub-mount and D designates a distance between light emitting points at opposite ends in the light emitting edge of the laser chip, materials of the sub-mount and the heat sink and the distance D are set to satisfy the following relation:≦5.48×A difference between stress acting on one laser element and another in the laser chip due to shrinkage of the heat sink when melted solder is cooled down is reduced so that a difference in light output characteristics between one light emitting point and another can be reduced.