Abstract: Illumination devices (20, 20', 20", 20'") for delivering ultraviolet light to an in vivo treatment site comprise an optical fiber (22) having an illumination window (40, 40', 40", 40'"). A circumferential contour (46, 46', 46", 46'") of the core is shaped along the illumination window so that, for an internally reflected ray travelling in the core, the internally reflected ray has differing angles of incidences along the illumination window. In addition, the contour of the circumferential core causes rays travelling parallel to a major axis of the optical fiber to strike the core-scattering layer interface, thereby resulting in greater irradiance. In one embodiment, in the illumination window (40') a circumferential contour (46') of the core is shaped by etching to have an essentially semi-conical shape.

Abstract: A coagulating scalpel including a cutting and coagulating element and a dissecting element. The dissecting element and cutting and coagulating element is positioned and configured and of such size that tissue to be cut can pass over or along a surface of the dissecting element and into the cutting zone of the scalpel. The surface of the dissecting element is adapted to permit substantially free passage of the tissue over or along the surface of the dissecting element upon movement of the scalpel.

Abstract: A narrow divergence, single quantum well, separate confinement, AlGaAs laser of the type which includes the following sequentially grown epitaxial layers: (a) an n-AlGaAs cladding layer; (b) an AlGaAs waveguide layer; (c) a GaAs quantum well layer; (d) an AlGaAs waveguide layer; (e) a p-AlGaAs cladding layer; and is improved to provide a far-field angular divergence in the order of thirty degrees (30.degree.), full width at half maximum (FWHM) with a reduced threshold current temperature sensitivity for use in electronic imaging printers.