Light emitting device with molded wavelength converting layer
View Patent ↗A flexible film comprising a wavelength converting material is positioned over a light source. The flexible film is conformed to a predetermined shape. In some embodiments, the light source is a light emitting diode mounted on a support substrate. The diode is aligned with an indentation in a mold such that the flexible film is disposed between the support substrate and the mold. Transparent molding material is disposed between the support substrate and the mold. The support substrate and the mold are pressed together to cause the molding material to fill the indentation. The flexible film conforms to the shape of the light source or the mold.
1. A method comprising:
disposing a first wavelength converting material over a light source;
aligning the light source with an indentation in a mold so that the light source is facing the indentation and the first wavelength converting material is between the light source and the mold;
positioning a flexible film comprising a second wavelength converting material between the first wavelength converting material and the mold;
disposing a transparent molding material between the light source and the mold; and
pressing the light source and the mold together to cause the transparent molding material to fill the indentation and to cause the flexible film to conform to a predetermined shape.
2. The method of claim 1 wherein the light source comprises a III-nitride light emitting diode mounted on a support substrate.
3. The method of claim 1 wherein the flexible film comprises a powder phosphor disposed in a silicone film.
4. The method of claim 3 wherein the silicone film is fully cured prior to said positioning.
5. The method of claim 3 wherein the silicone film is partially cured prior to said positioning.
6. The method of claim 3 wherein the flexible film further comprises a non-wavelength converting material, wherein the non-wavelength converting material changes an index of refraction of the flexible film.
7. The method of claim 3 wherein the first wavelength converting material is disposed in a first flexible film in direct contact with the light source, the method further comprising:
positioning the second flexible film in direct contact with the mold, wherein the transparent molding material is disposed between the first flexible film and the second flexible film.
8. The method of claim 1 wherein pressing the light source and the mold together to cause the transparent molding material to fill the indentation and to cause the flexible film to conform to a predetermined shape comprises creating a reduced pressure environment which draws the molding material into the indentation.
9. The method of claim 1 wherein disposing a first wavelength converting material over a light source comprises bonding a pre-formed layer to the light source.
10. The method of claim 9 wherein the pre-formed layer is a ceramic phosphor.
11. The method of claim 1 wherein disposing a first wavelength converting material over a light source comprises one of stenciling and screen printing the first wavelength converting material over the light source.
12. The method of claim 1 wherein disposing a first wavelength converting material over a light source comprises one of spraying, sedimenting, evaporating, and sputtering the first wavelength converting material over the light source.