Planar light-emitting device
A planar light-emitting device includes a plurality of light-emitting elements arranged at same intervals in a planar configuration, and a wavelength conversion member located above the plurality of light-emitting elements. The plurality of light-emitting elements is configured to emit blue light. The wavelength conversion member contains a phosphor that emits light when being excited by light emitted from the light-emitting elements. The plurality of light-emitting elements includes a first light-emitting element located in an outer perimeter region in a plan view, and a second light-emitting element located in a central region in the plan view. The central region is positioned inward of the outer perimeter region in the plan view. A peak wavelength of light emitted from the first light-emitting element is less than a peak wavelength of light emitted from the second light-emitting element.
1 . A planar light-emitting device, comprising:
a plurality of light-emitting elements arranged at same intervals in a planar configuration, the plurality of light-emitting elements configured to emit blue light; and
a wavelength conversion member located above the plurality of light-emitting elements, the wavelength conversion member containing a phosphor that emits light when being excited by light emitted from the plurality of light-emitting elements,
the plurality of light-emitting elements including
a first light-emitting element located in an outer perimeter region in a plan view, and
a second light-emitting element located in a central region in the plan view, the central region being positioned inward of the outer perimeter region in the plan view,
a peak wavelength of light emitted from the first light-emitting element being less than a peak wavelength of light emitted from the second light-emitting element, wherein
the plurality of light-emitting elements further includes a third light-emitting element located in an intermediate region positioned between the outer perimeter region and the central region in the plan view,
a peak wavelength of light emitted from the third light-emitting element is greater than the peak wavelength of the light emitted from the first light-emitting element and less than the peak wavelength of the light emitted from the second light-emitting element,
the plurality of light-emitting elements is arranged in a rectangular configuration in the plan view,
the outer perimeter region includes:
a first part including a corner of the rectangular configuration; and
a second part next to the first part,
the intermediate region includes a third part next to the first part,
a first-first light-emitting element and a second-first light-emitting element are located in the first part and the second part, respectively, and
the third light-emitting element is located in the third part, and
another second light-emitting element is located in the intermediate region.
2 . The device according to claim 1 , wherein
the plurality of light-emitting elements further includes an intervening light-emitting element located in the outer perimeter region in the plan view,
the intervening light-emitting element is positioned between adjacent ones of a plurality of the first light-emitting elements, and
a peak wavelength of light emitted from the intervening light-emitting element is equal to the peak wavelength of the light emitted from the second light-emitting element or less than the peak wavelength of the light emitted from the second light-emitting element.
3 . The device according to claim 1 , further comprising:
a substrate at which the plurality of light-emitting elements is disposed; and
a light-transmitting member covering at least one of the plurality of light-emitting elements on the substrate.
4 . The device according to claim 1 , further comprising:
a substrate at which the plurality of light-emitting elements is disposed; and
a demarcation member defining a plurality of regions each surrounding a respective one of the plurality of light-emitting elements on the substrate, the demarcation member being light-reflective.
5 . The device according to claim 1 , wherein
the wavelength conversion member is plate-shaped, and
the wavelength conversion member and the plurality of light-emitting elements are separated from each other.
6 . The device according to claim 1 , wherein
the phosphor contains:
at least one selected from a group consisting of β-sialon, chlorosilicate, silicate, BSON, perovskite, and thiogallate; and
at least one selected from a group consisting of KSF, KSAF, MGF, SCASN, CASN, and β-sialon.
7 . The device according to claim 1 , wherein
the peak wavelength of the light emitted from the first light-emitting element and the peak wavelength of the light emitted from the second light-emitting element are not less than 430 nm and not more than 460 nm.
8 . The device according to claim 7 , wherein
a difference between the peak wavelength of the light emitted from the first light-emitting element and the peak wavelength of the light emitted from the second light-emitting element is not less than 1 nm and not more than 10 nm.
9 . The device according to claim 2 , wherein
the phosphor contains:
at least one selected from a group consisting of β-sialon, chlorosilicate, silicate, BSON, perovskite, and thiogallate; and
at least one selected from a group consisting of KSF, KSAF, MGF, SCASN, CASN, and β-sialon.
10 . The device according to claim 4 , wherein
the phosphor contains:
at least one selected from a group consisting of β-sialon, chlorosilicate, silicate, BSON, perovskite, and thiogallate; and
at least one selected from a group consisting of KSF, KSAF, MGF, SCASN, CASN, and β-sialon.
11 . The device according to claim 2 , wherein
the peak wavelength of the light emitted from the first light-emitting element and the peak wavelength of the light emitted from the second light-emitting element are not less than 430 nm and not more than 460 nm.
12 . The device according to claim 4 , wherein
the peak wavelength of the light emitted from the first light-emitting element and the peak wavelength of the light emitted from the second light-emitting element are not less than 430 nm and not more than 460 nm.
13 . The device according to claim 6 , wherein
the peak wavelength of the light emitted from the first light-emitting element and the peak wavelength of the light emitted from the second light-emitting element are not less than 430 nm and not more than 460 nm.
14 . The device according to claim 9 , wherein
the peak wavelength of the light emitted from the first light-emitting element and the peak wavelength of the light emitted from the second light-emitting element are not less than 430 nm and not more than 460 nm.
15 . The device according to claim 10 , wherein
the peak wavelength of the light emitted from the first light-emitting element and the peak wavelength of the light emitted from the second light-emitting element are not less than 430 nm and not more than 460 nm.
16 . The device according to claim 1 , wherein
the third light-emitting element is located between the another second light-emitting element and a further second light-emitting element in the intermediate region.