LED/phosphor-LED hybrid lighting systems

DETAILED DESCRIPTION OF THE INVENTION The hybrid lighting system of the invention generally comprises selectively combining one or more certain LEDs with a phosphor-LED consisting of a blue LED and at least one phosphor which emits at certain light spectral wavelength (color), to produce white light.
FIG.
1A schematically depicts a typical LED 10 used in the invention.
The LED 10 is conventionally constructed using standard AlInGaN or AlInGaP processing and comprises an LED chip II mounted in a reflective metal dish or reflector 12 filled with a transparent epoxy 13.
FIG.
1B schematically depicts a typical phosphor-LED 14 used in the invention.
This LED 14 is substantially identical in construction to the LED of FIG.
1A, except that the epoxy 18 filling the reflector 16 contains grains 19 of one or more types of luminescent phosphor materials mixed homogeneously therein.
The phosphor grains 19 convert a portion of the light emitted by the LED chip 15 to light of a different spectral wavelength.
A primary advantage of the hybrid system of the invention is that it permits different lighting system performance parameters to be addressed and optimized as deemed important by varying the color and number of the LEDs and/or the phosphor of the phosphor-LED.
In particular, the system of the present invention can address and achieve higher available lumens-per-chip averages via balancing red and green and blue light components; smaller integral numbers of LEDs at balance; improved color rendering; and more efficient mixing via the phosphor-LED.
This in turn advantageously permits the manufacture of various types of products which are optimized for various applications using LED chips manufactured with standard AlInGaN and AlInGaP processing.
Each of the following embodiments illustrate how one or more of the above performance advantages can be achieved using the hybrid system of the invention.
FIG.
2 schematically depicts a first embodiment of the hybrid lighting system of the invention denoted by numeral 20