Patent ID: 8419781

Claim:
A handpiece for treating biological tissue, comprising: a source of electromagnetic radiation; a waveguide positioned to receive electromagnetic radiation from the source, the waveguide comprising: first and second ends, and a wall extending at least partially therebetween, the wall configured to transmit the electromagnetic radiation therethrough; a passage extending along a direction between said first and second ends; a fluorescent substance flowable within the passage; and an input port and an output port in fluid communication with the passage; an optical output element near one of the first and second ends of the waveguide; wherein the fluorescent substance is configured to absorb the electromagnetic radiation from the source through the wall and generate fluorescent light in response to the electromagnetic radiation, wherein the waveguide is configured to guide the fluorescent light emitted by the fluorescent substance towards the optical output element by internally reflecting at least a portion of the fluorescent light, and wherein the optical output element is configured to direct the fluorescent light towards biological tissue; and a fluid conduit in fluid communication with the input and output ports, the fluid conduit further configured to carry the fluorescent substance between the waveguide's passage and a fluid circulation system.