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US 10,312,417 B2Granted
Wavelength converted light emitting device
AssigneeKoninklijke Philips N.V.
InventorsGerd Mueller, Regina Mueller-Mach, Peter Josef Schmidt, Danielle Russell Chamberlin, Oleg Borisovich Shchekin, Hans-Helmut Bechtel
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Abstract
In a method according to embodiments of the invention, for a predetermined amount of light produced by a light emitting diode and converted by a phosphor layer comprising a host material and a dopant, and for a predetermined maximum reduction in efficiency of the phosphor at increasing excitation density, a maximum dopant concentration of the phosphor layer is selected.
Claims10
A method comprising:
- providing a phosphor layer overlying a light emitting diode for converting a wavelength emitted by the light emitting diode to a longer wavelength, the step of depositing the phosphor layer comprising:
- depositing a first region of the phosphor layer having a first dopant with a first dopant concentration, the first region emitting light of a first wavelength;
- and
- depositing a second region of the phosphor layer adjacent to the first region, the second region having the first dopant with a second dopant concentration, wherein the second dopant concentration is less than the first dopant concentration, the second region also emitting light of the first wavelength,
- wherein light emitted by the light emitting diode reaches the second region before the first region.
2 more elements
A structure comprising:
- a light emitting diode emitting light having a first peak wavelength;
- a phosphor layer disposed in a path of light emitted by the light emitting diode, the phosphor layer for absorbing light emitted by the light emitting diode and emitting light having a second peak wavelength;
- wherein the phosphor layer comprises a host material and a dopant, wherein the phosphor layer comprises:
- a first region having a first dopant with a first dopant concentration, the first region emitting light having the second peak wavelength;
- a second region having the first dopant with a second dopant concentration, wherein the second dopant concentration is less than the first dopant concentration, the second region also emitting light of the second peak wavelength;
- and
- the first region and the second region are arranged such that light emitted by the light emitting diode reaches the second region before the first region.
4 more elements
Dependencies are inferred from the claim text.