Abstract: A scanning optical system for delivering electromagnetic radiation onto tissue to be treated is cooperative with a lightguide or optical fiber. Radiation to be delivered is provided by a source thereof via the optical fiber. The optical system includes an optical projection arrangement comprising a plurality of lenses cooperatively arranged with the lightguide. A first of the lenses is arranged to receive radiation emerging from the lightguide. The beam of radiation is passed through the projection arrangement to form a treatment spot the radiation on the tissue. Scanning is effected by causing relative motion between the exit-end of said lightguide and at least the first lens, transverse to the optical axis of the projection arrangement. The treatment spot undergoes a related transverse motion over the tissue. In one example scanning is effected by moving the first lens with the lightguide fixed. The first lens is moved using an arrangement of piezo-electric actuators.

Abstract: An optical system is arranged to deliver electromagnetic radiation in first and second different wavelengths to tissue to be treated therewith. The optical system forms the different-wavelength radiations into beams of different sizes and combines the beams on a common optical path. The different-wavelength radiations on the common optical path are projected by the optical system onto the tissue to be treated to form overlapping treatment spots of different sizes. In one example, the treatment spots are concentric and the size of the treatment spots and the ratio of the treatment-spot sizes can be selectively varied.

Abstract: A method for delivering electromagnetic radiation onto tissue to be treated with the radiation includes delivering the radiation onto the tissue in a treatment-spot having a polygonal shape such as a rectangle or a hexagon. The polygonal shape is selected such that a region of the tissue to be treated can be completely covered by a plurality of such shapes essentially without overlapping the shapes. The radiation to be delivered is passed through a lightguide having a cross-section of the polygonal shape. Radiation exiting the lightguide is projected onto the tissue via a plurality of optical elements to provide the treatment-spot.

Abstract: A scanning optical system for delivering electromagnetic radiation onto tissue to be treated is cooperative with a lightguide or optical fiber. Radiation to be delivered is provided by a source thereof via the optical fiber. The optical system includes an optical projection arrangement comprising a plurality of lenses cooperatively arranged with the lightguide. A first of the lenses is arranged to receive radiation emerging from the lightguide. The beam of radiation is passed through the projection arrangement to form a treatment spot the radiation on the tissue. Scanning is effected by causing relative motion between the exit-end of said lightguide and at least the first lens, transverse to the optical axis of the projection arrangement. The treatment spot undergoes a related transverse motion over the tissue. In one example scanning is effected by moving the first lens with the lightguide fixed. The first lens is moved using an arrangement of piezo-electric actuators.

Abstract: A laser includes an asymmetrical laser-resonator formed between a concave maximally-reflecting mirror and a plane output-coupling mirror. The laser-resonator includes a transversely optically-pumped gain-medium rod asymmetrically located in the laser-resonator closer to the output-coupling mirror than to the maximally-reflecting mirror. Components of the laser-resonator are configured, dependent upon the thermal-lensing coefficient of the gain-medium and optical pumping power, such that the laser-resonator operates as a stable resonator generating a multimode circulating laser-beam. The beam has a width at the maximally-reflecting mirror greater than its width at the output-coupling mirror for reducing laser-damage to the maximally-reflecting mirror. The beam symmetrically fills the gain-medium thereby providing optimum laser-energy extraction from the gain-medium.