Method of producing an LED light source with lens

• US 6,746,295 B2
• Filed: 06/05/2003
• Issued: 06/08/2004
• Est. Priority Date: 04/22/1999
• Status: Expired due to Term

• Current Assignee: OSRAM GmbH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Sorg, Jörg-Erich
• Primary Examiner(s): Ramsey, Kenneth J.
• Assistant Examiner(s): Santiago, Mariceli
• Application Number:
  US10/454,919
• Publication Number:
  US 20030211804A1
• Time in Patent Office: 369 Days
• Field of Search: 340/815.57, 340/815.45, 340/815.54, 340/815.76, 438/22, 438/26, 438/27, 438/29, 445/24, 445/25, 257/95, 257/98, 257/100
• US Class Current: 445/24
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

The light source has an LED, preferably produced for the surface-mounting technique, embedded in a transparent material filling. A converter substance is integrated in the filling for the at least partial wavelength conversion of the light emitted by the LED. A lens is glued onto the transparent material filling. The material filling has a convex surface and the lens has a concave underside entering into a form fit with the convex surface of the material filling.

Claims

1. A method of producing an LED light source, which comprises the following steps:

forming a recess with a planar bottom face in a basic body;

mounting an LED on the bottom face;

filling the recess with a defined amount of a transparent material containing converter material;

providing a lens with a concave underside;

while the transparent material is still in a liquid form, inserting the lens with the concave underside into the transparent material; and

curing the transparent material.

2. The method according to claim 1, wherein the transparent material is a resin material.

3. The method according to claim 1, wherein during the step of curing the transparent material, an upper side of the transparent material enters into a form fit with the concave underside of the lens and the concave underside of the lens causes the upper side of the transparent material to form into a convex surface.

4. The method according to claim 1, wherein the converter material is for at least partially converting a wavelength of light emitted by the LED.

5. The method according to claim 1, which comprises fabricating the lens before performing the step of inserting the lens with the concave underside into the transparent material.

6. The LED light source according to claim 1, wherein the defined amount of the transparent material is less than a free volume of the recess with the LED disposed therein.

7. The method according to claim 1, which comprises:

during the step of curing the transparent material, ensuring that an upper side of the transparent material enters into a form fit with the concave underside of the lens and the concave underside of the lens causes the upper side of the transparent material to form into a convex surface; and

ensuring that the convex surface of the transparent material and the concave underside of the lens have a substantially constant distance from the LED.

8. The method according to claim 1, which comprises:

during the step of curing the transparent material, ensuring that an upper side of the transparent material enters into a form fit with the concave underside of the lens and the concave underside of the lens causes the upper side of the transparent material to form into a convex surface;

providing the LED with an active radiating area; and

ensuring that the convex surface of the transparent material and the concave underside of the lens are formed at a substantially constant distance from a geometrical center point of the active radiating area of the LED.

9. The method according to claim 1, which comprises:

providing the LED as a blue light-emitting LED based on GaN; and

providing the converter material for converting light radiation in a blue spectral range into light radiation in a yellow spectral range.

10. The method according to claim 1, which comprises:

providing the LED as a UV-emitting LED; and

providing the converter material for converting UV light into a visible spectral range.

11. The method according to claim 1, which comprises:

during the step of curing the transparent material, ensuring that an upper side of the transparent material enters into a form fit with the concave underside of the lens and the concave underside of the lens causes the upper side of the transparent material to form into a convex surface; and

setting a distance of the convex surface from the LED such that a degree of conversion along an optical path length of light radiated from the LED is substantially 50%.

12. The method according to claim 1, which comprises:

during the step of curing the transparent material, ensuring that an upper side of the transparent material enters into a form fit with the concave underside of the lens and the concave underside of the lens causes the upper side of the transparent material to form into a convex surface;

providing the LED with an active radiating area; and

setting a distance of the convex surface from a geometrical center point of the active radiating area such that a degree of conversion along an optical path length of the light radiated from the LED is substantially 50%.

13. The method according to claim 1, which comprises providing the LED as a surface-mounted component.

14. The method according to claim 1, which comprises constructing the transparent material from a resin material.

15. The method according to claim 1, which comprises constructing the basic body from a thermoplastic material.

16. The method according to claim 1, which comprises:

mounting the LED on a first leadframe and electrically connecting the first leadframe to a first electrical contact area of the LED;

using a bond wire to electrically connect a second leadframe to a second electrical contact area of the LED; and

producing the basic body by injection molding around the first leadframe and the second leadframe.

17. The method according to claim 1, which comprises providing the basic body with sloping and reflective side walls that define the recess.