Light emitting device package and backlight unit comprising the same

Abstract

Disclosed is a light emitting element package having excellent heat radiation performance and high luminance, and a backlight unit including the same. The light emitting element package includes a package including a lead frame, a light emitting element provided on the lead frame, and a molded material combined with the lead frame and having an opening for emitting light generated by the light emitting element, and a reflection structure having an opening corresponding to the opening of the molded material, and contacting the molded material.

The invention claimed is: 
     
       1. A light emitting element package, comprising:
 a lead frame;   a light emitting element on the lead frame;   a molded material combined with the lead frame and having an opening for emitting light generated by the light emitting element;   a reflection structure having an opening that corresponds to the opening of the molded material and contacting the molded material; and   an adhesive layer provided in at least part of a region between the molded material and the reflection structure to fix the reflection structure onto the molded material,   wherein the adhesive layer has a first thickness in an area adjacent to the light emitting element and a second thickness in an area away from the light emitting element, and wherein the first thickness is greater than the second thickness.   
     
     
       2. The light emitting element package according to  claim 1 , wherein the reflection structure comprises:
 a supporting portion contacting the molded material and provided continuously or discretely along a circumference of the opening of the molded material; and   a radial portion contacting the supporting portion and extending radially from the molded material relative to a direction along which light generated by the light emitting element emits.   
     
     
       3. The light emitting element package according to  claim 1 , wherein the molded material comprises a supporting portion provided continuously or discretely along a circumference of the opening of the molded material, and
 wherein the reflection structure comprises a radial portion contacting the supporting portion and having a radial shape extending radially from the molded material relative to a direction along which light generated by the light emitting element emits.   
     
     
       4. The light emitting element package according to  claim 1 , wherein the molded material comprises a supporting portion provided continuously or discretely along a circumference of the opening of the molded material, and
 wherein the reflection structure has a shape that corresponds to the supporting portion of the molded material, and contacts the molded material.   
     
     
       5. The light emitting element package according to  claim 1 , wherein recesses or concave and convex portions are provided on the molded material, and
 wherein the reflection structure is fitted into the recesses or concave and convex portions.   
     
     
       6. The light emitting element package according to  claim 1 , wherein the thickness of the adhesive layer is gradually reduced away from the light emitting element. 
     
     
       7. A light emitting element package, comprising:
 a lead frame;   a light emitting element on the lead frame;   a molded material combined with the lead frame and haying an opening for emitting light generated by the light emitting element; and   a reflection structure having an opening that corresponds to the opening of the molded material and contacting the molded material,   wherein the reflection structure comprises a radial surface formed in a radial shape extending radially from the molded material relative to a direction along which light generated by the light emitting element emits, and   wherein the radial surface of the reflection structure forms a first angle with a main emission direction of light generated by the light emitting element, from a point where the radial surface contacts the molded material to a first point away from the molded material, and forms a second angle with the main emission direction from the first point to a second point further away from the molded material compared to the first point, wherein the second angle is greater than the first angle.   
     
     
       8. The light emitting element package according to  claim 7 , further comprising a first resin layer that includes a fluorescent material and is provided in the opening of the molded material to cover the light emitting element. 
     
     
       9. The light emitting element package according to  claim 8 , further comprising a light-transmitting second resin layer that covers the first resin layer and contacts the radial surface. 
     
     
       10. The light emitting element package according to  claim 7 , further comprising:
 a light-transmitting second resin layer provided in the opening of the molded material to cover the light emitting element; and   a first resin layer that includes a fluorescent material, covers the second resin layer, and contacts the radial surface.   
     
     
       11. The light emitting element package according to  claim 1 , wherein the reflection structure comprises metal. 
     
     
       12. The light emitting element package according to  claim 1 , wherein a surface of the supporting portion facing the opening of the molded material has a radial shape extending radially relative to a direction along which light generated by the light emitting element emits. 
     
     
       13. The light emitting element package according to  claim 1 , wherein part of the reflection structure is inserted into the opening of the molded material, and
 Wherein the other part of the reflection structure, protruding from the opening of the molded material has a radial shape extending radially from the molded material relative to a direction along which light generated by the light emitting element emits.   
     
     
       14. A light emitting element package, comprising:
 a lead frame;   a light emitting element on the lead frame;   a molded material combined with the lead frame and having an opening for emitting light generated by the light emitting element;   a reflection structure having an opening that corresponds to the opening of the molded material, and contacting the molded material;   a supporting portion provided discretely or continuously on the molded material to fix the reflection structure onto the molded material; and   an adhesive layer provided in at least part of a region between the molded material and the reflection structure, and having a first thickness in an area adjacent to the light emitting element and a second thickness in an area away from the light emitting element, wherein the first thickness is greater than the second thickness.   
     
     
       15. A backlight unit, comprising:
 a reflective sheet;   a light guide plate on or above the reflective sheet; and   alight emitting element package according to  claim 1 , configured to illuminate the light guide plate.   
     
     
       16. A method of manufacturing a light emitting element package, comprising:
 providing a lead frame, a light emitting element, and a molded material in a package, the molded material having an opening for emitting light generated by the light emitting element;   aligning a reflection structure in contact with the molded material, the reflection structure having an opening that corresponds to the opening of the molded material; and   fixing the reflection structure onto the molded material with an adhesive layer provided between the molded material and the reflection structure, the adhesion layer having a first thickness in an area adjacent to the light emitting element and a second thickness less than the first thickness in an area away from the light emitting element.    
     
     
       17. The method of claim 16, further comprising providing a supporting portion that contacts the molded material continuously or discretely along a circumference of the opening of the molded material.  
     
     
       18. The method of claim 17, wherein the support portion extends along the circumference of the opening of the molded material and protrude from corners of the molded material along a z-axis generally parallel to a direction of light emitted by the light emitting element.  
     
     
       19. The method of claim 16, wherein recesses or concave and convex portions are provided on the molded material, and at least a portion of the reflection structure is fitted into the recesses or concave and convex portions.  
     
     
       20. The method of claim 16, wherein the reflection structure comprises a radial surface formed in a radial shape extending radially from the molded material relative to a direction along which light generated by the light emitting element emits.  
     
     
       21. The method of claim 20, wherein the radial surface of the reflection structure forms a first angle with a main emission direction of light generated by the light emitting element from a point where the radial surface contacts the molded material to a first point away from the molded material and forms a second angle with the main emission direction from the first point to a second point further away from the molded material compared to the first point, wherein the second angle is greater than the first angle.  
     
     
       22. The method of claim 16, further comprising filling a first resin layer comprising a fluorescent material in the opening of the molded material to cover the light emitting element.  
     
     
       23. The method of claim 22, further comprising covering the first resin layer with a second resin layer, wherein the second resin layer contacts a radial surface of the reflective structure.  
     
     
       24. The method of claim 16, further comprising filling a light-transmitting second resin layer in the opening of the molded material to cover the light emitting element and covering the second resin layer with a first resin layer comprising a fluorescent material, wherein the first resin layer contacts a radial surface of the reflective structure.  
     
     
       25. A method of manufacturing a light emitting element package, comprising:
 providing a lead frame, a light emitting element, and a molded material in a package, the molded material having a first opening for emitting light generated by the light emitting element, the first opening being defined by a first inner surface having a first slope line;   aligning a reflection structure in contact with the molded material, the reflection structure having a second opening that corresponds to the first opening of the molded material, the second opening being defined by a second inner surface having a second slope line; and   fixing the reflection structure onto the molded material, such that the first slope line and the second slope line form a continuous straight line,   wherein fixing the reflection structure onto the molded material comprises providing an adhesive layer between the molded material and the reflection structure,   wherein the adhesive layer has a first thickness in an area adjacent to the light emitting element and a second thickness in an area away from the light emitting element, and   wherein the first thickness is greater than the second thickness.    
     
     
       26. The method of claim 25, wherein the first inner surface and the second inner surface define a common circumference when the reflection structure is fixed onto the molded material.  
     
     
       27. The method of claim 25, wherein the lead frame is exposed to an exterior of the molded material.  
     
     
       28. The method of claim 27, wherein the second inner surface is in flush with the first inner surface along all circumferential direction of the first opening of the molded material.  
     
     
       29. The method of claim 25, wherein the adhesive layer is not exposed either to the first opening and the second opening.  
     
     
       30. The method of claim 25, further comprising providing recesses or concave and convex portions on the molded material and fitting a portion of the reflection structure into the recesses or concave and convex portions.  
     
     
       31. A method of manufacturing a light emitting element package, comprising:
 providing a lead frame, a light emitting element, and a molded material in a package, the molded material having a first inner surface defining a first opening for emitting light generated by the light emitting element;   aligning a reflection structure in contact with the molded material, the reflection structure having a second inner surface defining a second opening that corresponds to the first opening of the molded material; and   fixing the reflection structure onto the molded material,   wherein the molded material comprises a plurality of recesses along a circumference of the first opening of the molded material, and the reflection structure comprises a plurality of protrusions along a circumference of the second opening of the reflection structure, and   wherein fixing the reflection structure onto the molded material comprises mating the plurality of protrusions of the reflection structure with the plurality of recesses of the molded material and providing an adhesive layer between the molded material and the reflection structure,   wherein the adhesive layer has a first thickness in an area adjacent to the light emitting element and a second thickness in an area away from the light emitting element, and   wherein the first thickness is greater than the second thickness.    
     
     
       32. The method of claim 31, wherein the molded material has a substantially rectangular outer shape.  
     
     
       33. The method of claim 32, wherein at least two opposing sides of the molded material comprises each of the plurality of recesses.