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US 2012/0057325 A1Published application
Illumination device with a phosphor
AssigneeKoninklijke Philips Electronics N.V.
InventorRifat Ata Mustafa Hikmet
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AssigneeKoninklijke Philips Electronics N.V.
InventorRifat Ata Mustafa Hikmet
Estimating the term…
The invention relates to an illumination device and a method adapted for illuminating applications. The illumination device (5) with a phosphor (1) comprising at least one light emitting surface which is adapted for emitting phosphor light in a predefined solid angle, a light source (2) being adapted for emitting optical radiation directed to the phosphor (1), a waveguide (3), and a reflector (4), wherein the phosphor (1) is optically coupled to the waveguide (3), the exit surface of the illumination device (5) from which light is emitted is larger than any single light emitting surface of the phosphor (1), and the reflector (4) is adapted for reflecting at least a part of the optical radiation emitted from the illumination device (5) by a surface different from the exit surface of the illumination device (5). In this way, a high light extraction efficiency from a single surface of a luminescent material and at the same time a high quantum efficiency of the illumination device is achieved.
(canceled)
The illumination device according to claim 16, wherein the waveguide comprises an optical contact with the phosphor from at least one light emitting surface.
The illumination device according to claim 16, wherein the phosphor comprises a low scattering transparent material.
The illumination device according to claim 16, wherein the reflector comprises a diffuse reflector.
The illumination device according to claim 16, wherein the waveguide comprises a flat waveguide coupled from the top surface and/or a side surface to the phosphor.
The illumination device according to claim 16, wherein the waveguide comprises a diffuse reflector.
The illumination device according to claim 16, wherein the optical coupling between the phosphor and the waveguide comprises a material with a refractive index≦1.4 matching the refractive index of the phosphor or the waveguide.
The illumination device according to claim 16, wherein a side surface of the phosphor comprises an inclination angle to the entrance surface of the waveguide different from a perpendicular angle.
The illumination device according to claim 16, further comprising a transparent layer with a transparent material different from the material of the waveguide, wherein the transparent layer is arranged between the phosphor and the waveguide.
The illumination device according to claim 16, wherein an exit surface of the waveguide and/or the exit surface of the illumination device comprises a shape corresponding to a plain shape, a concave shape, a convex shape and/or a zigzag shape.
The illumination device according to claim 16, further comprising at least a film arranged on top of an exit surface of the waveguide for polarizing the optical radiation irradiated from the exit surface of the waveguide.
The illumination device according claim 16, further comprising a selective reflector adapted for selectively transmitting and/or reflecting optical radiation, wherein the selective reflector is arranged in an optical path between the light source and the phosphor.
The illumination device according to claim 16, further comprising a heat sink for cooling the phosphor.
(canceled)
An illumination device comprising
Dependencies are inferred from the claim text.