Optical pickup device, semiconductor laser device and housing usable for the optical pickup device, and method of manufacturing semiconductor laser device

Abstract

A semiconductor laser device includes a first lead having a plate-like mounting portion on which a semiconductor laser chip is mounted and a lead portion extending from the mounting portion, a second lead extending along the lead portion of the first lead, and a retention portion made of an insulative material that integrally retains the first lead and the second lead. The mounting portion of the first lead has a back surface exposed from the retention portion, and the first lead further has a tie bar portion projecting from the mounting portion along the back surface of the mounting portion.

1 . A semiconductor laser device comprising: 
 a first lead having a plate-like mounting portion on which a semiconductor laser chip is mounted and a lead portion extending from the mounting portion;    a second lead extending along the lead portion of the first lead; and    a retention portion made of an insulative material that integrally retains the first lead and the second lead,    wherein the mounting portion of the first lead has a back surface exposed from the retention portion, and the first lead further has a tie bar portion projecting from the mounting portion along the back surface of the mounting portion.    
   
   
       2 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the tie bar portion projects in a direction perpendicular to an optical axis of the semiconductor laser chip.    
   
   
       3 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the tie bar portion has an end in a projecting direction thereof, the end being located farther away from the semiconductor laser chip than any portion of the mounting portion.    
   
   
       4 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the tie bar portion has a width equal to or greater than a width of the semiconductor laser chip.    
   
   
       5 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the second lead has an anti-fall portion for restraining movement of the second lead relative to the retention portion.    
   
   
       6 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the first lead has a recess portion at a front edge of the mounting portion, the recess portion receding so as to indicate a position in which the semiconductor laser chip is mounted; and    an inner edge of the recess portion corresponding to a portion just ahead of the semiconductor laser chip is inclined with respect to an optical axis of the semiconductor laser chip.    
   
   
       7 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the first lead comprises an odd-shaped frame of a partially varied thickness.    
   
   
       8 . The semiconductor laser device as claimed in  claim 7 , wherein 
 the mounting portion of the first lead has a thickness that is smaller in a part on which the semiconductor laser chip is positioned than in remainder of the mounting portion.    
   
   
       9 . The semiconductor laser device as claimed in  claim 7 , wherein 
 a thickness of the lead portion of the first lead is greater than a thickness of the mounting portion so that a difference in level between an upper surface of the semiconductor laser chip and an upper surface of the lead portion of the first lead is reduced.    
   
   
       10 . The semiconductor laser device as claimed in  claim 9 , wherein 
 the mounting portion and the lead portion of the first lead are welded together.    
   
   
       11 . The semiconductor laser device as claimed in  claim 9 , wherein 
 the upper surface of the semiconductor laser chip and the upper surface of the lead portion of the first lead are electrically connected together via a wire.    
   
   
       12 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the mounting portion of the first lead has a through hole in a region other than a mounting region in which the semiconductor laser chip is located, said through hole connecting a top surface and a back surface of the mounting portion;    the back surface of the mounting portion has a recess, which is continuous from the through hole and surrounds a periphery of the through hole; and    the recess is filled with a material of the retention portion supplied from a top surface side of the mounting portion through the through hole.    
   
   
       13 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the mounting portion of the first lead has a cut-and-raised portion in a region other than a mounting region in which the semiconductor laser chip is located, said cut-and-raised portion defining a through-hole connecting a top surface and a back surface of the mounting portion; and    a space on a back side of the cut-and-raised portion is filled with a material of the retention portion supplied from a front surface side of the mounting portion through the through hole.    
   
   
       14 . The semiconductor laser device as claimed in  claim 1 , wherein 
 each of the lead portion of the first lead and the second lead has a local thin neck at an outer lead portion projecting from the retention portion.    
   
   
       15 . The semiconductor laser device as claimed in  claim 14 , wherein 
 each of the leads comprises a core material plated with a metal having good solder wettability to the core material.    
   
   
       16 . The semiconductor laser device as claimed in  claim 15 , wherein 
 the core material comprises Cu, and an outermost surface of the plating metal is made of Sn or Au.    
   
   
       17 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the retention portion is made of a resin.    
   
   
       18 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the retention portion is made of ceramics.    
   
   
       19 . The semiconductor laser device as claimed in  claim 1 , wherein 
 the retention portion has a black color.    
   
   
       20 . The semiconductor laser device as claimed in  claim 1 , wherein 
 a cover for protecting the semiconductor laser chip is provided on the retention portion.    
   
   
       21 . An optical pickup device comprising: 
 a housing; and    the semiconductor laser device as claimed in  claim 1 ,    wherein the semiconductor laser device is mounted to the housing with both the mounting portion of the first lead and the tie bar portion being in contact with the housing.    
   
   
       22 . An optical pickup device comprising: 
 a semiconductor laser device having a metallic heat sink and a semiconductor laser chip fixed to a top surface of the heat sink; and    a housing to support the semiconductor laser device;    the housing having a metallic contact surface put in surface contact with a greater part of a back surface of the heat sink.    
   
   
       23 . The optical pickup device as claimed in  claim 22 , wherein 
 roughly entirety of the back surface of the heat sink is put in surface contact with the contact surface of the housing.    
   
   
       24 . The optical pickup device as claimed in  claim 22 , wherein 
 the back surface of the heat sink is fixed to the contact surface of the housing with a metallic brazing material.    
   
   
       25 . The optical pickup device as claimed in  claim 22 , wherein 
 the housing has side surfaces which are curved surfaces.    
   
   
       26 . The optical pickup device as claimed in  claim 22 , wherein 
 the heat sink is provided with a recess portion or a through hole.    
   
   
       27 . The optical pickup device as claimed in  claim 22 , wherein 
 the semiconductor laser device has a resin provided only on a top surface side of the heat sink.    
   
   
       28 . The optical pickup device as claimed in  claim 24 , wherein 
 at least one of the back surface of the heat sink or the contact surface of the housing has been surface-treated to improve wettability of the metallic brazing material.    
   
   
       29 . An optical pickup device comprising: 
 a semiconductor laser device having a metallic heat sink and a semiconductor laser chip fixed to a top surface of the heat sink;    a housing to support the semiconductor laser device; and    a substrate disposed between the back surface of the heat sink and the housing,    the substrate having a top surface put in surface contact with a greater part of a back surface of the heat sink, and    the housing having a metallic contact surface put in surface contact with a greater part of a back surface of the substrate.    
   
   
       30 . The optical pickup device as claimed in  claim 29 , wherein 
 roughly entirety of the back surface of the substrate is put in surface contact with the top surface of the heat sink, and    roughly entirety of the back surface of the substrate is put in surface contact with the contact surface of the housing.    
   
   
       31 . A semiconductor laser device comprising: 
 a first lead including a plate-like mounting portion;    a second lead which is separate from the first lead;    a retention portion made of an insulative material that integrally retains the first lead and the second lead;    a semiconductor laser chip that is mounted in a front part of the mounting portion and emits laser light forward and backward;    a monitoring photodetector provided at the mounting portion such that the monitoring photodetector is disposed behind the semiconductor laser chip; and    a light reflector which is separate from the retention portion and disposed behind the monitoring photodetector on the mounting portion, wherein the light reflector, upon receipt of at least part of laser light emitted backward from the semiconductor laser chip, reflects the light toward the monitoring photodetector.    
   
   
       32 . The semiconductor laser device as claimed in  claim 31 , wherein 
 the light reflector is made of a white resin.    
   
   
       33 . The semiconductor laser device as claimed in  claim 31 , wherein 
 the light reflector is made of a resin plated with metal.    
   
   
       34 . The semiconductor laser device as claimed in  claim 31 , wherein 
 the light reflector is made of a metal.    
   
   
       35 . The semiconductor laser device as claimed in  claim 31 , wherein 
 the light reflector has a reflection surface inclined with respect to a laser light emitting direction of the semiconductor laser chip so as to reflect the laser light from the semiconductor laser chip toward the monitoring photodetector.    
   
   
       36 . The semiconductor laser device as claimed in  claim 31 , wherein 
 the semiconductor laser chip is mounted on the mounting portion via a plate-like submount, and the monitoring photodetector is housed in a portion, of the submount, which is located behind the semiconductor laser chip.    
   
   
       37 . A semiconductor laser device manufacturing method for manufacturing the semiconductor laser device claimed in  claim 31 , wherein at least the monitoring photodetector and the light reflector are concurrently bonded onto the mounting portion.  
   
   
       38 . A semiconductor laser device comprising: 
 a first lead having a plate-like mounting portion on which a semiconductor laser chip is mounted and a lead portion extending from the mounting portion;    a second lead extending along the lead portion of the first lead; and    a retention portion made of an insulative material that integrally retains the first lead and the second lead, wherein the retention portion includes a frame member disposed on a semiconductor laser chip side of the first lead, and the frame member has a window portion for emitting laser light from the semiconductor laser chip;    a cap to be fit in the frame member of the retention portion; and    a pressure contact structure that urges the frame member of the retention portion against the cap, and vice versa, in a direction roughly parallel to an optical axis of the semiconductor laser chip so as to bring the frame member and the cap in pressure contact with each other when the cap is fit in the frame member of the retention portion.    
   
   
       39 . The semiconductor laser device as claimed in  claim 38 , wherein 
 the cap has a projection engaged with the window portion of the frame member of the retention portion.    
   
   
       40 . The semiconductor laser device as claimed in  claim 38 , wherein 
 the cap has one or more projections that project in a direction roughly parallel to the optical axis of the semiconductor laser chip,    the frame member of the retention portion has one or more recess portions receding in the direction roughly parallel to the optical axis of the semiconductor laser chip, and    the pressure contact structure has said one or more projections and said one or more recess portions, and said or each projection is engaged with a corresponding recess portion while being brought in pressure contact therewith when the cap is attached to the frame member of the retention portion.    
   
   
       41 . The semiconductor laser device as claimed in  claim 40 , wherein 
 said or each projection has a hemispherical shape, and    said or each recess portion has a shape complementary to the projection.    
   
   
       42 . The semiconductor laser device as claimed in  claim 40 , wherein 
 the cap has two opposite outer surfaces which extend in a direction roughly perpendicular to the optical axis of the semiconductor laser chip,    the frame member of the retention portion has two opposite inner surfaces which extend in the direction roughly perpendicular to the optical axis of the semiconductor laser chip,    the projections are provided at the two outer surfaces of the cap, two to outer surface, and    the recess portions are provided at the two inner surfaces of the frame member of the retention portion, two to inner surface.    
   
   
       43 . The semiconductor laser device as claimed in  claim 38 , wherein 
 the cap has a handling lug.    
   
   
       44 . The semiconductor laser device as claimed in  claim 43 , wherein 
 the first lead has tie bar portions that project in opposite directions roughly perpendicular to the optical axis of the semiconductor laser chip from respective opposite end edges of the mounting portion that are situated in the directions roughly perpendicular to the optical axis of the semiconductor laser chip, and    the lug of the cap is formed so as to be oriented in a direction roughly parallel to the optical axis of the semiconductor laser chip when the cap is fit in the frame member of the retention portion.    
   
   
       45 . The semiconductor laser device as claimed in  claim 43 , wherein 
 the lug is defined between two lug-forming recess portions that are opposed to each other at an interval on one surface of the cap.    
   
   
       46 . The semiconductor laser device as claimed in  claim 45 , wherein 
 the lug-forming recess portions each have a crescentic shape.    
   
   
       47 . The semiconductor laser device as claimed in  claim 38 , wherein 
 the retention portion and the cap are made of an identical material.    
   
   
       48 . The semiconductor laser device as claimed in  claim 38 , wherein 
 the retention portion and the cap is made of a resin.    
   
   
       49 . The semiconductor laser device as claimed in  claim 38 , wherein 
 the retention portion and the cap have a black color.    
   
   
       50 . A semiconductor laser device which comprises a metal support having a mounting surface and a front surface adjoining the mounting surface, and a semiconductor laser chip mounted on the mounting surface, and which emits laser light from a light-emitting end surface located on the front surface side of the semiconductor laser chip, wherein 
 at least part of the front surface is inclined with respect to the light-emitting end surface and parallel to a plane obtained by rotating the light-emitting end surface around a perpendicular line to the mounting surface.    
   
   
       51 . The semiconductor laser device as claimed in  claim 50 , wherein 
 a submount made of a dielectric substance or a semiconductor is provided between the semiconductor laser chip and the metal support.    
   
   
       52 . The semiconductor laser device as claimed in  claim 51 , wherein 
 an end surface located on the front surface side of the submount is inclined with respect to the light-emitting end surface and parallel to a plane obtained by rotating the light-emitting end surface around the perpendicular line to the mounting surface.    
   
   
       53 . The semiconductor laser device as claimed in  claim 50 , wherein 
 the metal support is a frame made of a metal thin plate.    
   
   
       54 . The semiconductor laser device as claimed in  claim 51 , wherein 
 an end surface located on the front surface side of the submount is roughly parallel to said at least part of the front surface.    
   
   
       55 . A semiconductor laser device comprising: 
 a main body;    a semiconductor laser chip fixed to the main body; and    a first rotation guide mechanism that is provided at the main body and allows the main body to be rotatably supported so that a laser light emitting direction of the semiconductor laser chip is adjustable.    
   
   
       56 . The semiconductor laser device as claimed in  claim 55 , wherein 
 the first rotation guide mechanism enables the main body to rotate around a neighborhood of a light-emitting point of the semiconductor laser chip.    
   
   
       57 . The semiconductor laser device as claimed in  claim 55 , wherein 
 the main body is made of a metal plate.    
   
   
       58 . The semiconductor laser device as claimed in  claim 55 , wherein 
 the first rotation guide mechanism has a curved portion provided at an edge of the main body.    
   
   
       59 . The semiconductor laser device as claimed in  claim 55 , wherein 
 the first rotation guide mechanism comprises a recess portion provided at the main body.    
   
   
       60 . The semiconductor laser device as claimed in  claim 59 , wherein 
 the recess portion consists of a cut provided at an edge of the main body.    
   
   
       61 . The semiconductor laser device as claimed in  claim 58 , wherein 
 an inner wall surface of the recess portion is a conical surface.    
   
   
       62 . The semiconductor laser device as claimed in  claim 55 , wherein 
 the first rotation guide mechanism comprises a groove provided at the main body in such a manner that the groove roughly coincides with a circumference of a circle centered on a neighborhood of the light-emitting point of the semiconductor laser chip.    
   
   
       63 . The semiconductor laser device as claimed in  claim 55 , wherein 
 the main body comprises a metal plate and a resin member integrated with the metal plate, and    the first rotation guide mechanism comprises a groove provided at the resin member in such a manner that the groove roughly coincides with a circumference of a circle centered on the semiconductor laser chip.    
   
   
       64 . A housing comprising: 
 a housing main body; and    a second rotation guide mechanism that is provided at the housing main body and rotatably supports a semiconductor laser device so that a laser light emitting direction of the semiconductor laser device is adjustable.    
   
   
       65 . The housing as claimed in  claim 64 , wherein 
 the second rotation guide mechanism enables the semiconductor laser device to rotate around a neighborhood of the light-emitting point of the semiconductor laser device.    
   
   
       66 . The housing as claimed in  claim 64 , wherein 
 the second rotation mechanism comprises a guide portion provided at the housing main body and having a curved surface.    
   
   
       67 . The housing as claimed in  claim 64 , wherein 
 the second rotation mechanism comprises at least one projection.    
   
   
       68 . The housing as claimed in  claim 67 , wherein 
 the projection has a conical shape.    
   
   
       69 . The housing as claimed in  claim 67 , wherein 
 the projection has a circular arc shape.    
   
   
       70 . The housing as claimed in  claim 67 , wherein 
 the second rotation mechanism has one projection.    
   
   
       71 . The housing as claimed in  claim 67 , wherein 
 the second rotation mechanism has two projections.    
   
   
       72 . An optical pickup device comprising a semiconductor laser device and a housing, wherein 
 the semiconductor laser device comprises: 
 a main body;  
 a semiconductor laser chip fixed to the main body; and  
 a first rotation guide mechanism that is provided at the main body and allows the main body to be rotatably supported so that a laser light emitting direction of the semiconductor laser chip is adjustable, and  
   the housing comprises: 
 a housing main body; and  
 a second rotation guide mechanism that is provided at the housing main body and rotatably supports the semiconductor laser device so that the laser light emitting direction of the semiconductor laser device is adjustable.