Abstract:
A semiconductor light emitting device includes an LED and an associated recipient luminophoric medium that includes respective first through fourth luminescent materials that down-convert respective first through fourth portions of the radiation emitted by the LED to radiation having respective first through fourth peak wavelengths. The first peak wavelength is in the green color range and the second through fourth peak wavelengths are in the red color range. The second and third luminescent materials each emit light having a full-width half maximum bandwidth of at least 70 nanometers, while the fourth luminescent material emits light having a full-width half maximum bandwidth of less than 60 nanometers. Embodiments that only include three luminescent materials are also disclosed.
Abstract:
A semiconductor light emitting device includes an LED and an associated recipient luminophoric medium that includes respective first through fourth luminescent materials that down-convert respective first through fourth portions of the radiation emitted by the LED to radiation having respective first through fourth peak wavelengths. The first peak wavelength is in the green color range and the second through fourth peak wavelengths are in the red color range. The second and third luminescent materials each emit light having a full-width half maximum bandwidth of at least 70 nanometers, while the fourth luminescent material emits light having a full-width half maximum bandwidth of less than 60 nanometers. Embodiments that only include three luminescent materials are also disclosed.
Abstract:
A semiconductor light emitting device includes an LED and an associated recipient luminophoric medium that includes respective first through fourth luminescent materials that down-convert respective first through fourth portions of the radiation emitted by the LED to radiation having respective first through fourth peak wavelengths. The first peak wavelength is in the green color range and the second through fourth peak wavelengths are in the red color range. The second and third luminescent materials each emit light having a full-width half maximum bandwidth of at least 70 nanometers, while the fourth luminescent material emits light having a full-width half maximum bandwidth of less than 60 nanometers. Embodiments that only include three luminescent materials are also disclosed.
Abstract:
Light emitting devices include an LED that emits light having a dominant wavelength in the blue color range and a recipient luminophoric medium that is configured to down-convert at least some of the light emitted by the LED. In these devices, the recipient luminophoric medium may include at least a green phosphor that down-converts the radiation emitted by the LED to radiation having a peak wavelength that is between about 525 nanometers and about 545 nanometers, a yellow phosphor that down-converts the radiation emitted by the LED to radiation having a peak wavelength that is between about 550 nanometers and about 570 nanometers, and a red (Ca1-x-ySrxEu2+y)SiAlN3 phosphor. The red (Ca1-x-ySrxEu2+y)SiAlN3 phosphor may have a europium content of at least 0.025.
Abstract:
Solid state light emitting apparatuses include blue LEDs (e.g., including short wavelength and long wavelength blue LEDs in combination) to stimulate green lumiphors, with supplemental emissions by red lumiphors and/or red solid state light emitters, to provide aggregate emissions with high S/P ratio (e.g., ≧1.95) and high color rendering values (e.g., ≧85), preferably in combination with high brightness and high luminous efficacy. In certain embodiments, a light emitting apparatus may be devoid of a LED having a peak wavelength of from 470-599 nm and/or devoid of lumiphors with peak wavelengths in the yellow range. Multiple LEDs may be arranged in an emitter package. A fabrication method includes mounting multiple solid state emitters (e.g., with a first blue and a second red emitter) to a common substrate, applying a stencil or mask over the second emitter, applying a lumiphoric material over the first emitter, and removing the stencil or mask.
Abstract:
A solid state light emitting device includes a solid state light emitter and a lumiphoric material that are selected for use with one another to provide light emissions with improved (i.e., reduced) thermal droop A solid state emitter having a short peak emission wavelength (e.g., in a visible range at or below 440 nm) seemingly less than optimal at room temperature for use with a particular lumiphor can trigger more efficient stimulation of lumiphor emissions at high temperatures. Enhanced epitaxial structures also inhibit decrease of radiant flux by LEDs at elevated temperatures.
Abstract:
A semiconductor light emitting device includes an LED and an associated recipient luminophoric medium that includes respective first through fourth luminescent materials that down-convert respective first through fourth portions of the radiation emitted by the LED to radiation having respective first through fourth peak wavelengths. The first peak wavelength is in the green color range and the second through fourth peak wavelengths are in the red color range. The second and third luminescent materials each emit light having a full-width half maximum bandwidth of at least 70 nanometers, while the fourth luminescent material emits light having a full-width half maximum bandwidth of less than 60 nanometers. Embodiments that only include three luminescent materials are also disclosed.
Abstract:
Solid state light emitting apparatuses include blue LEDs (including but not limited to a combination of short wavelength and long wavelength blue LEDs) to stimulate green lumiphors, with supplemental emissions by either red lumiphors and/or red solid state light emitters, to provide aggregate emissions with high S/P ratio (e.g., at least 1.95) and favorably high color rendering values (e.g., 85 or greater), preferably in combination with high brightness and high luminous efficacy. In certain embodiments, a solid state light emitting apparatus may be devoid of a LED having a peak wavelength of from 470-599 nm and/or devoid of lumiphors peak wavelengths in the yellow range. Multiple LEDs may be arranged in an emitter package.