Semiconductor light emitting device

Abstract

A semiconductor light emitting device includes a mount section having an insulating property connected to a heat sink, a plurality of semiconductor laser elements disposed on the mount section, and a heat radiation block having an insulating property disposed on the plurality of semiconductor laser elements. A first wiring made of a metal is disposed on an upper surface of the mount section, and a second wiring made of a metal is disposed on a lower surface of the heat radiation block, a part of the second wiring being electrically connected to the first wiring. By electrically connecting the first wiring and the second wiring to each of the plurality of semiconductor laser elements, the plurality of semiconductor laser elements are connected in series, and have a same polarity with each other at a side that each of the plurality of semiconductor laser elements is connected to the first wiring.

What is claimed is: 
     
         1 . A semiconductor laser device comprising:
 a mount section;   a first wiring, a second, and a third wiring connected to an upper surface of the mount section;   a first semiconductor laser element having an electrode at an upper side and an electrode at a lower side; and   the electrode at the lower side of the first semiconductor laser element is joined to an upper surface of the first wiring; wherein:   the first semiconductor laser element has a front side which is a laser emission end surface, a back side opposite to the front side and sides between the front side and the back side,   the second wiring includes a first L shape portion in which a part thereof is cut out in plan view,   the first L shape portion has a portion opposite to the side of the first semiconductor laser element and a portion opposite to the back side of the first semiconductor laser element,   the third wiring includes a second L shape portion in plan view, and   the second L shape portion has a portion opposite to a side of first L shape portion.   
     
     
         2 . The semiconductor laser device according to  claim 1 , wherein the second L shape portion has a portion overlapping the cut out. 
     
     
         3 . The semiconductor laser device according to  claim 1 , further comprising a second semiconductor laser element having an electrode at an upper side and an electrode at a lower side, wherein the electrode at the lower side of the second semiconductor laser element is joined to an upper surface of the second wiring. 
     
     
         4 . The semiconductor laser device according to  claim 3 , wherein the first semiconductor laser element and the second semiconductor laser element are connected in series. 
     
     
         5 . The semiconductor laser device according to  claim 3 , wherein the first semiconductor laser element and the second semiconductor are placed parallel to each other. 
     
     
         6 . The semiconductor laser device according to  claim 1 , further comprising a third semiconductor laser element having an electrode at an upper side and an electrode at a lower side, wherein the electrode at the lower side of the third semiconductor laser element is joined to an upper surface of the third wiring. 
     
     
         7 . The semiconductor laser device according to  claim 6  wherein, the first semiconductor laser element and the third semiconductor laser element are connected in series. 
     
     
         8 . The semiconductor laser device according to  claim 6 , wherein the first semiconductor laser element and the third semiconductor are placed parallel to each other. 
     
     
         9 . The semiconductor laser device according to  claim 1 , wherein a width of the second wiring on the back side is larger than a width of the second wiring on the front side along a direction perpendicular to a longitudinal direction of the first semiconductor laser element. 
     
     
         10 . The semiconductor laser device according to  claim 1 , wherein a width of the third wiring on the back side is larger than a width of the third wiring on the front side along a direction perpendicular to a longitudinal direction of the first semiconductor laser element. 
     
     
         11 . The semiconductor laser device according to  claim 1 , wherein a first wiring is a rectangular shape in plan view. 
     
     
         12 . The semiconductor laser device according to  claim 1 , wherein a first wiring and the first semiconductor laser element are joined via a solder layer.