Lamp with enhanced chroma and color preference
AssigneeGeneral Electric Company
InventorsKatalin Tóth, István Károly Deme, Attila Kulcsár, Gáza István Szeghy
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Abstract
Disclosed herein are low pressure discharge lamps having enhanced chroma and color preference. improved color quality scale, especially at elevated color temperatures, is provided. The light generated by the light-emitting elements of the lamp, when the lamp is energized, has Color Preference Scale values, as well as delta chroma values for fifteen color samples of the Color Quality Scale, within select parameters.
Claims18
A low pressure discharge lamp having evenly enhanced chroma and improved color preference, which lamp when energized has a total light emission exhibiting a correlated color temperature (CCT) of between about 2000 kelvin to about 4500 kelvin, the lamp comprising:
- a light-transmissive envelope,
- a fill gas sealed inside said envelope, and
- a phosphor composition having a light emission when energized;
- and
- wherein when said lamp is energized said lamp has a total light emission which:
- (a) has a color point below the Planckian locus in the CIE standard chromaticity diagram;
- (b) exhibits delta chroma values for each of VS1 through VS15 of from about −10.0 to about +12.5, the delta chroma values measured in the CIE LAB space;
- and
- (c) exhibits a Color Preference Scale Qp value of at least about 88.
A low pressure discharge lamp having evenly enhanced chroma and improved color preference, which lamp when energized has a total light emission exhibiting a correlated color temperature of between about 2000 kelvin to about 4500 kelvin, the lamp comprising:
- a light-transmissive envelope,
- a fill gas sealed inside said envelope, and
- a phosphor composition having a light emission when energized;
- and
- wherein when said lamp is energized said lamp has a total light emission which:
- (a) exhibits delta chroma values for each of VS1 through VS15 of from about −10.0 to about +12.5, the delta chroma values measured in the CIE LAB space;
- and
- (b) exhibits a Color Preference Scale Qp value of at least about 88;
- wherein said phosphor composition comprises:
- a first red phosphor having a peak emission in the range of from about 590 to about 630 nm and a half-value width of from about 1 to about 30 nm, and optionally a second red phosphor having a peak emission in the range of from about 590 to about 670 nm and a half-value width of from about 30 to about 100 nm;
- a green phosphor having a peak emission in the range of from about 500 to about 570 nm and a half-value width of from about 1 to about 30 nm;
- and
- a blue phosphor having a peak emission in the range of from about 450 to about 500 nm and a half-value width of from about 30 to about 100 nm;
- wherein each phosphor in the composition may emit one or more colors.
Dependencies are inferred from the claim text.