The illumination and laser source comprises an illumination source (36) emanating illumination light (11) focused onto an output optical fiber (60) of 400 microns diameter or less thereby forming an illumination spot size which is of sufficient intensity to provide surgically useful illumination through said optical fiber (60) during a surgical procedure. The illumination and laser source further comprises a laser treatment light source providing laser treatment light (14) upon said output optical fiber (60) whereby both said laser treatment light (14) and said illumination light (11) transmit through said optical fiber (60) and an illumination light dimming mechanism capable of dimming said illumination light (11) without affecting said laser treatment light (14). The invention is further directed to a method of transmitting illumination light (11) and laser treatment light (14) through a single optical fibers(60).
