Cree Gmbh

David Clatterbuck

Michael John Bergmann

Brian Thomas Collins

Jasper S Cabalu

Florin A Tudorica

Iliya Todorov

James Ibbetson

Nalini Gupta

Harry A Seibel, Ii

Charles Draper

Douglas E Kinkenon

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.

Light-emitting devices having closely-spaced broad-spectrum and narrow-spectrum luminescent materials and related methods

Light emitting devices having closely-spaced broad-spectrum and narrow-spectrum luminescent materials and related methods

A light emitting diode (LED) component comprises an LED having a dominant wavelength in a range of from about 425 nm to less than 460 nm and a phosphor in optical communication with the LED. The phosphor includes a host lattice comprising yttrium aluminum garnet (YAG), and may include an activator comprising Ce and a substitutional dopant comprising Ga incorporated in the host lattice. An emission spectrum of the phosphor has a maximum intensity in a wavelength range of from about 540 nm to about 570 nm, and an excitation spectrum of the phosphor comprises an intensity at 440 nm equivalent to at least about 85% of a maximum intensity of the excitation spectrum.

Light emitting diode (LED) component comprising a phosphor with improved excitation properties

A light emitting diode (LED) component comprises an LED having a dominant wavelength in a range of from about 425 nm to about 475 nm, and a first phosphor and a second phosphor are in optical communication with the LED. The first phosphor has a peak emission wavelength in the range of from about 600 nm to about 700 nm, and the second phosphor has a peak emission wavelength in the range of from about 500 nm to about 600 nm. An excitation spectrum of the first phosphor includes, at excitation wavelengths longer than 530 nm, no intensities greater than about 60% of a maximum intensity of the excitation spectrum.

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., &#x2267;1.95) and high color rendering values (e.g., &#x2267;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.

Solid state lighting apparatus with high scotopic/photopic (S/P) ratio

Provided herein are phosphor compositions that include a YAG phosphor that is substituted with gallium, such as YCeAlGaO, wherein a, b, c, d and z are positive numbers. Also provided are solid state light emitting devices that include a YAG phosphor that is substituted with gallium.

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Raleigh, NC, United States of America

David Clatterbuck