An arrangement for monitoring the power delivered by a photon channeling element including an integrating chamber to receive an output end of the photon channeling element and an optical surface positioned to reflect a portion of the laser-light exiting the photon channeling element at substantially normal incidence to the beam centerline. The integrating chamber may be adapted to collect substantially all of the laser-light reflected from the optical surface. The arrangement may also include a sensor in optical contact with a portion of the integrating chamber that is out of the path of laser-light reflected from the optical surface.