Patent ID: 8657476

Claim:
An elongated LED lighting arrangement, comprising: a) an elongated light pipe extending between first and second ends; the light pipe having a sidewall between said ends facing outwardly of the light pipe; the light pipe comprising homogeneous optical material between said ends, b) a first LED light source comprising at least one LED tuned to efficiently provide to the light pipe, via said first end, light within a first wavelength band; c) a first dichroic mirror interposed between the first LED light source and said first end; the mirror tuned to pass more than 90 percent of light within said first wavelength band from said first LED light source into the light pipe via said first end; d) down-converting means on said sidewall tuned to efficiently absorb light rays from said first LED light source within a wavelength band that includes at least 80 percent of said first wavelength band and to emit lower-energy light rays outside of the light pipe at respectively higher wavelengths; e) light-extracting means on said sidewall for extracting from the light pipe some light rays within said first wavelength band without changing the wavelengths of the foregoing light; f) the down-converting means and the light-extracting means being arranged so that the light emitted by the down-converting means and the light extracted from the light pipe by the light-extracting means intermix to produce light, the majority of which has a composite color determined by the foregoing light emitted and the foregoing light extracted; and g) the first dichroic mirror receiving some light emitted by the down-converting means and reflecting back into the light pipe more than 80 percent of the light received by the mirror, so that the reflected light can be extracted from the side of the light pipe by the light-extracting means.