Light emitting device
AssigneeNichia Corporation
InventorKenji Asai
Life of this patent
Estimating the term…
Abstract
A light emitting device includes a light emitting element having a peak emission wavelength of 410 nm to 440 nm and a phosphor member. The phosphor member includes a first phosphor having a peak emission wavelength of 430 nm to 500 nm and containing an alkaline-earth phosphate, a second phosphor having a peak emission wavelength of 440 nm to 550 nm and containing at least one of an alkaline-earth aluminate and a silicate containing Ca, Mg, and Cl, a third phosphor having a peak emission wavelength of 500 nm to 600 nm and containing a rare-earth aluminate, a fourth phosphor having a peak emission wavelength of 610 nm to 650 nm and containing a silicon nitride containing Al and at least one of Sr and Ca, and a fifth phosphor having a peak emission wavelength of 650 nm to 670 nm and containing a fluorogermanate.
Claims20
A light emitting device comprising:
- a light emitting element having a peak emission wavelength in a range of 410 nm to 440 nm;
- and
- a phosphor member, the phosphor member containing a phosphor comprising:
- a first phosphor having a peak emission wavelength in a range of 430 nm to 500 nm and having a half value width of a emission spectrum in a range of 29 nm to 49 nm;
- a second phosphor having a peak emission wavelength in a range of 440 nm to 550 nm and having a half value width of a emission spectrum in a range of 58 nm to 78 nm or 50 nm to 75 nm;
- a third phosphor having a peak emission wavelength in a range of 500 nm to 600 nm and having a half value width of a emission spectrum in a range of 95 nm to 115 nm;
- a fourth phosphor having a peak emission wavelength in a range of 610 nm to 650 nm and having a half value width of a emission spectrum in a range of 80 nm to 100 nm;
- and
- a fifth phosphor having a peak emission wavelength in a range of 650 nm to 670 nm and having a half value width of a emission spectrum in a range of 45 nm or less,
- wherein a percentage content of the first phosphor to a total content of the phosphor is in a range of 20 mass % to 80 mass %, and wherein
- when the light emitting device is configured to emit light of correlated color temperature in a range of 5,500 K to 7,500 K, and a ratio of peak optical intensity of the first phosphor to the light emitting element is in a range of 0.4 to 1.5;
- when the light emitting device is configured to emit light of correlated color temperature in a range of 4,500 K to 5,500 K, and a ratio of peak optical intensity of the first phosphor to the light emitting element is in a range of 0.4 to 1.5;
- when the light emitting device is configured to emit light of correlated color temperature in a range of 3,500 K to 4,500 K, and a ratio of peak optical intensity of the first phosphor to the light emitting element is in a range of 0.3 to 1.3;
- and
- when the light emitting device is configured to emit light of correlated color temperature in a range of 2,500 K to 3,500 K, and a ratio of peak optical intensity of the first phosphor to the light emitting element is in a range of 0.2 to 1.4;
- and
- wherein the light emitting device is configured to emit light with a sum of special color rendering Indices R9 to R15 of 600 or greater.
Dependencies are inferred from the claim text.