Patent attributes
An elongated LED lighting arrangement comprises an elongated light pipe with homogeneous optical material between first and second ends. In an exemplary embodiment, an LED provides blue light to the light pipe via a first dichroic mirror tuned to pass blue light. Down-converting means on sidewall of the light pipe, tuned to receive blue light, absorbs blue light from the LED and to emit lower-energy light outside of the light pipe at respectively higher wavelengths. Light-extracting means on the sidewall extract from the light pipe some blue light without changing the wavelengths of the foregoing light. Light from the down-converting means and the light-extracting means are combined to provide a composite color. The first dichroic mirror receives some light emitted by the down-converting means and reflects back into the light pipe more than 80 percent of the light received by the mirror.
