Manufacture of optical diffusers composed of reflowable materials
A method of making optical diffuser elements ( 20 ) includes providing a substrate ( 100 ) composed of a polymer material and having openings ( 102 ) therein. An optical diffuser material ( 110 ) is dispensed into the openings ( 102 ), and the optical diffuser material ( 110 ) is hardened to form a sheet ( 200 ) composed of regions of the optical diffuser material ( 110 ) surrounded laterally by the polymer material. The method includes separating the sheet ( 200 ) into multiple optical diffuser elements ( 30 ) that retain their mechanical stability and optical properties when subjected to a reflow process.
1. A method comprising:
providing a substrate composed of a polymer material and having openings therein;
dispensing an reflowable optical diffuser material into the openings;
hardening the optical diffuser material to form a sheet composed of regions of the optical diffuser material surrounded laterally by the polymer material; and
separating the sheet into a plurality of optical diffuser elements,
wherein the optical diffuser elements retain their mechanical stability and optical properties when subjected to reflow processes at a temperature of more than 270° C.
2. The method of claim 1 wherein the substrate is composed of a black epoxy.
3. The method of claim 2 wherein the substrate is formed by a vacuum injection molding process.
4. The method of claim 1 wherein the optical diffuser material is dispensed by jetting.
5. The method of claim 1 wherein the optical diffuser material is an epoxy material.
6. The method of claim 1 wherein the optical diffuser material is operable to diffuse light in the visible range part of the electromagnetic spectrum.
7. The method of claim 1 further including removing excess optical diffuser material that is present outside the openings.
8. The method of claim 7 wherein the excess optical diffuser material is removed by polishing.
9. The method of claim 7 wherein the excess optical diffuser material is removed by lapping.
10. The method of claim 1 including subjecting one or more of the optical diffuser elements to a reflow process.
11. The method of claim 1 including subjecting one or more of the optical diffuser elements to a process at a temperature of at least 270° C.
12. An optical diffuser element comprising:
a first epoxy operable to diffuse light in the visible range part of the electromagnetic spectrum; and
a black epoxy material laterally surrounding the first epoxy material,
wherein the optical diffuser element retains its mechanical stability and optical properties when subjected to a reflow process,
wherein the optical diffuser elements retains its mechanical stability and optical properties when subjected to a temperature of higher than 270° C.