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US 7,922,352 B2Granted
Device and method for emitting output light using multiple light sources with photoluminescent material
AssigneeAvago Technologies General IP (Singapore) Pte. Ltd.
InventorsJanet Bee Yin Chua, Yue Hoong Lau
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Abstract
A device and method for emitting output light utilizes multiple light sources to produce original light having different peak wavelengths. A first light source of the device is configured to generate first light having a peak wavelength in the blue wavelength range, while a second light source of the device is configured to generate second light having a peak wavelength in the red wavelength range. Some of the original light emitted from at least the first light source is converted into light having a peak wavelength longer than the peak wavelength of the original light using a photoluminescent material to produce the output light.
Claims15
A semiconductor device for emitting output light,
- the device comprising:
- a mounting structure;
- a first light emitting diode die positioned over the mounting structure, the first light emitting diode die being configured to emit first light having a peak wavelength in the blue wavelength range;
- a second light emitting diode die positioned over the mounting structure, the second light emitting diode die being configured to emit second light having a peak wavelength in the red wavelength range;
- and
- a transparent encapsulant that encapsulates the first and second light emitting diode dies, the transparent encapsulant having first and second portions, the first portion of the transparent encapsulant including a wavelength-shifting region containing a photoluminescent material, the photoluminescent material having a property to convert at least some of the first light emitted by the first light emitting diode die into third light having a peak wavelength in the green wavelength range and longer than the peak wavelength of the first light, the second portion of the transparent encapsulant does not contain photoluminescent material, wherein the first light emitting diode die is situated in the first portion of the transparent encapsulant and the second light emitting diode die is situated in the second portion of the transparent encapsulant;
- wherein the first light, emitted by the first light emitting diode die, having a peak wavelength in the blue wavelength range;
- the second light, emitted by the second light emitting diode die, having a peak wavelength in the red wavelength range;
- and the third light, emitted by the first light emitting diode die and converted by the photoluminescent material into light having a peak wavelength in the green wavelength range are components of the output light emitted by the semiconductor device, and wherein the output light emitted from the semiconductor device having a high color-rendering index.
6 more elements
A method for emitting output light from a light emitting device, said method comprising:
- generating first light having a peak wavelength in the blue wavelength range from a first light emitting diode die of the light emitting device;
- generating second light having a peak wavelength in the red wavelength range from a second light emitting diode die of the light emitting device;
- receiving the first light at a wavelength-shifting region optically coupled to at least the first light emitting diode die, including converting at least some of the first light into third light having a peak wavelength longer than the peak wavelength of the first light using a photoluminescent material contained in the wavelength-shifting region of a transparent encapsulant that encapsulates the first and second light emitting diode dies, wherein the transparent encapsulant having first and second portions, the first portion of the transparent encapsulant including the wavelength-shifting region containing the photoluminescent material, the second portion of the transparent encapsulant does not contain photoluminescent material, wherein the first light emitting diode die is situated in the first portion of the transparent encapsulant and the second light diode die is situated in the second portion of the transparent encapsulant;
- and
- emitting from the light emitting device the first light having a peak wavelength in the blue wavelength range, the second light having a peak wavelength in the green wavelength range and longer than the peak wavelength of the first light, and the third light having a peak wavelength in the red wavelength range as components of the output light.
2 more elements
An apparatus for providing illumination, the apparatus comprising:
- at least one light emitting device, the light emitting device comprising:
- a mounting structure;
- a first light emitting diode die positioned over the mounting structure, the first light emitting diode die being configured to emit the light having a peak wavelength in the blue wavelength range;
- a second light emitting diode die positioned over the mounting structure, the second light emitting diode die being configured to emit second light having a peak wavelength in the red wavelength range;
- and
- a transparent encapsulant that encapsulates the first and second light emitting diode dies, the transparent encapsulant having first and second portions, the first portion of the transparent encapsulant including a wavelength-shifting region containing a photoluminescent material, the photoluminescent material having a property to convert at least some of the first light emitted by the first light emitting diode die into third light having a peak wavelength in the green wavelength range and longer than the peak wavelength of the first light, the second portion of the transparent encapsulant not containing photoluminescent material, wherein the first light emitting diode die is situated in the first portion of the transparent encapsulant and the second light emitting diode is situated in the second portion of the transparent encapsulant that does not contain photoluminescent material;
- wherein the first light, emitted by the first light emitting diode die, having a peak wavelength in the blue wavelength range;
- the second light, emitted by the second light emitting diode die, having a peak wavelength in the red wavelength range;
- and the third light, emitted by the first light emitting diode die and converted by the photoluminescent material in the first portion of the transparent encapsulant into light having a peak wavelength in the green wavelength range being components of output light emitted from the light emitting device, the output light emitted from the light emitting device having a high color-rendering index;
- and
- a light transmitting panel optically coupled to the light emitting device to receive the output light, the light transmitting panel being configured to provide illumination using the output light of the light emitting device.
8 more elements
Dependencies are inferred from the claim text.