Abstract: The laser surgical applicator according to the invention is used for contact vaporization of tissue and has a light guide with a quartz glass core at whose distal end a contact tip made of an optically transparent solid material is located. The contact tip has a quartz glass sheath in which at least the quartz glass core of the light guide runs coaxially at a distance from the inside wall and the distal end of the quartz glass core is molten with the distal end of the quartz glass sheath to form an optically transparent tip.

Abstract: For an interstitial thermotherapeutic treatment of biological tissue in which, for generating a coagulation necrosis, the radiation of the laser within a radiation period is guided into the tissue by way of a fiber optic waveguide, the laser power is reduced continuously or in steps during the radiation period.

Abstract: A surgical laser instrument suitable for the alternate contant cutting and no-contact coagulating of biological tissue by means of a fiber-optically guided irradiation of a laser. Radiation which is emitted by the pyrolytic glowing of at least partially carbonized biological tissue, is received by the distal end of the fiber-optic light guide, guided back to a radiation detector, and is detected in a spectral region between 0.3 and 0.9 .mu.m, while the laser radiation is filtered out. The radiation output of the laser is controlled by means of the detector output signal, to a value under the destruction threshold of the fiber-optic light guide in such a manner that the radiation emitted during the burning of the biological tissue to be cut as well as of the tissue residues adhering to the distal end of the fiber-optic light guide and burnt into it, does not exceed a predetermined value.

Abstract: An ink ribbon device having a holder for a ribbon spool which is pivotably mounted on a frame which supports the spool drive device. When the spool is inserted into the holder, a slide on the holder top is operated against the force of a spring, and engages guide slots. The holder then automatically is guided to the operating position and the spool engages the drive device. Upon movement of the holder for unloading, the spool is ejected by the spring.