Method and apparatus for generating white light from solid state light emitting devices
View Patent ↗An optical device capable of generating warm light using an array of phosphor islands situated over a phosphor layer is disclosed. The device includes a solid state light emitter, a phosphor layer, and phosphor islands. The solid state light emitter, in an aspect, is a light emitting diode (“LED”) capable of converting electrical energy to optical light. The phosphor layer is disposed over the solid state light emitter for generating luminous cool light in response to the optical light. Multiple phosphor islands are disposed on the phosphor layer for converting cool light to warm light, wherein the phosphor islands are evenly distributed over the phosphor layer.
1. A light emitting device, comprising:
a solid state light emitter capable of converting electrical energy to optical light;
a phosphor layer disposed over the solid state light emitter for generating luminous cool white light in response to the optical light, wherein the phosphor layer has a first range of optical wavelengths; and
a plurality of phosphor islands disposed over the phosphor layer for converting the cool white light to warm light, wherein the phosphor islands have a second range of optical wavelengths, wherein each of the plurality of phosphor islands is individually deposited onto the phosphor layer.
2. The device of claim 1 , further comprising a light extracting layer disposed between the phosphor layer and the solid state light emitter for extracting the optical light from the solid state light emitter.
3. The device of claim 2 ,
wherein the light extracting layer is a clear silicone layer; and
wherein the solid state light emitter is a light emitter diode (“LED”).
4. The device of claim 3 , wherein the light extracting layer is structured in a dome shape capable of extracting and scattering the optical light from the LED to the phosphor layer.
5. The device of claim 1 ,
wherein the phosphor islands are arranged in a substantial evenly distributed formation over the phosphor layer; and
wherein the first range of optical wavelengths has shorter optical wavelengths than the second range of optical wavelengths.
6. The device of claim 5 ,
wherein the first range of optical wavelengths is from 490 nanometers (“nm”) to 590 nm; and
wherein the second range of optical wavelengths is from 590 nm to 750 nm.
7. The device of claim 1 ,
wherein the phosphor layer includes yellow phosphor materials; and
wherein the plurality of phosphor islands includes red phosphor materials.
8. The device of claim 1 ,
wherein the phosphor layer includes green phosphor materials; and
wherein the plurality of phosphor islands includes orange phosphor dots.
9. The device of claim 1 , wherein the plurality of phosphor islands is arranged in a substantial evenly distributed array of red phosphor objects capable of emitting red light.
10. The device of claim 9 , wherein each of the plurality of phosphor islands is structured in a dome shape for scattering red light.
11. A light emitting device, comprising:
a light emitter diode (“LED”) able to provide blue light in accordance with electrical energy;
a green phosphor layer disposed over the LED and capable of generating luminous cool white light in response to the blue light, the green phosphor layer having a first side configured to receive the blue light and a second side configured to emit the cool white light, wherein the green phosphor layer has a first range of optical wavelengths; and
a plurality of red phosphor islands disposed on the second side of the green phosphor layer for generating warm light based on the cool white light, wherein the red phosphor islands have a second range of optical wavelengths.
12. The device of claim 11 , further comprising a light extracting layer disposed between the green phosphor layer and the LED for extracting the blue light from the LED.
13. The device of claim 12 ,
wherein the light extracting layer is a clear silicone layer; and
wherein the LED is a solid state light emitter.
14. The device of claim 13 , wherein the light extracting layer is structured in a dome shape capable of extracting and scattering the blue light from the LED to the green phosphor layer.
15. The device of claim 11 ,
wherein the red phosphor islands are arranged in a substantial evenly distributed formation over the green phosphor layer; and
wherein the first range of optical wavelengths has shorter optical wavelengths than the second range of optical wavelengths.
16. The device of claim 15 ,
wherein the first range of optical wavelengths is from 490 nanometers (“nm”) to 590 nm; and
wherein the second range of optical wavelengths is from 590 nm to 750 nm.
17. The device of claim 11 ,
wherein the green phosphor layer includes yellow phosphor materials; and
wherein the plurality of red phosphor islands includes red phosphor materials.
18. The device of claim 11 ,
wherein the green phosphor layer includes green phosphor materials; and
wherein the plurality of red phosphor islands includes orange phosphor dots.
19. The device of claim 11 , wherein the plurality of red phosphor islands is arranged in a substantial evenly distributed array of red phosphor objects capable of emitting red light.
20. The device of claim 11 , wherein each of the plurality of red phosphor islands is individually deposited onto the phosphor layer.