White lamps with enhanced color contrast
AssigneeLumination LLC
InventorEmil Vergilov Radkov
Life of this patent
Estimating the term…
Abstract
A lighting apparatus for emitting white light including a semiconductor light source emitting radiation with a peak at from about 250 nm to about 500 nm; a first phosphor having a peak emission between about 450 and 550 nm; and a second phosphor having a peak emission between about 615 and 670 nm; wherein the overall emission spectrum of the lighting apparatus has a depression between about 550 and 615 nm, said depression extending to between about 5% and 25% of the highest intensity of the emission spectrum of the lighting apparatus in the region from 400 to 700 nm. In this apparatus, the red-green color contrast is increased versus the referent illuminant.
Claims22
A lighting apparatus for emitting white light having enhanced red-green color contrast and comprising:
- a light source emitting radiation having a peak emission at from about 250 to 500 nm;
- and
- a phosphor blend radiationally coupled to said light source comprising:
- a first phosphor material having a peak emission between about 450 and 550 nm and a second phosphor material having a peak emission between about 615 and 670 nm;
- wherein an overall emission spectrum of the lighting apparatus has a depression between about 550 and 615 nm, said depression extending to between about 5% and 25% of the highest intensity of the emission spectrum of the lighting apparatus in the region from 400 to 700 nm;
- and said second phosphor is free of (Mg,Ca,Sr,Ba,Zn)4Si2O8:Eu2+,Mn2+.
A method for making a lighting apparatus for emitting white light having enhanced red-green color contrast, the method including the steps of:
- providing a light source emitting radiation having a peak emission at from about 250 to 500 nm;
- providing a phosphor blend comprising:
- a first phosphor material having a peak emission between about 450 and 550 nm and a second phosphor material having a peak emission between about 615 and 670 nm;
- and
- radiationally coupling said phosphor blend to said light source, wherein an overall emission spectrum of the lighting apparatus has a depression between about 550 and 615 nm, said depression extending to between about 5% and 25% of the highest intensity of the emission spectrum of the lighting apparatus in the region from 400 to 700 nm;
- and said second phosphor is free of (Mg,Ca,Sr,Ba,Zn)4Si2O8:Eu2+,Mn2+.
Dependencies are inferred from the claim text.