Abstract: A visual (e.g. liquid crystal) screen displays a sequence of graphics presentations and a specific event. The graphics sequence (e.g. visual representations of products in a market) has a display priority except when the specific event occurs. The specific event may be in graphics or alphanumeric form and related or unrelated to the graphics sequence. When the specific event has been displayed, the graphics sequence has priority again. In one embodiment, the specific event may be products identified and priced at a checkout counter by a bar code scanner or a keyboard. This information is processed alphanumerically. The processed information is displayed on the screen until the transaction completion (e.g. total purchase price is displayed). After a designated (e.g. 30 seconds) time following the purchase price display, the sequence of graphics presentations resumes display priority.

Abstract: An optically pumped mid-infrared solid-state laser with high pulse repetition rate is described for use in laser surgery. The laser produces a wavelength between 1.7 and 4.0 microns, and is optically pumped. The rise and fall times of the pump pulses are sufficiently short to avoid thermal lensing induced instability. The laser provides an increased rate of tissue cutting without necessitating an increase in the pulse energy.

Abstract: A laser surgery apparatus including a contact tip comprising an input face having a surface for receiving laser energy from an optical waveguide directed along an axis of propagation. The surface is inclined relative to the axis of propagation such that an angle of incidence between the laser light and the surface is approximately equal to Brewster's angle. Another aspect of the invention includes coating a portion of the tip body with a coating that is reflective to the laser energy. One preferred embodiment comprises a tip body coated with a single coating consisting essentially of a material which is biologically compatible with tissue to prevent generation of a toxic tissue response. A further aspect of the invention includes a tip configuration having a generally conical exterior with a substantially flat surface disposed obliquely to a core axis of the tip body.

Abstract: A corneal sculpting system utilized for performing surgery to reshape the cornea of the eye. The system includes a laser delivery system that is coupled to a filter positioning system and a corneal topography system. The filter positioning system suspends a sculpting filter above the surface of the cornea. The sculpting filter controls the level of tissue removal that occurs in each area of the cornea by absorbing a certain percentage of the incident laser energy in various areas of the filter. The positioning system also has a conduit for delivering water to the corneal surface. A thin layer of water is heated by the application of the laser to cause microexplosions that dislodge and propel the tissue to ablate the cornea. The corneal topography system provides real time feedback on the curvature of the cornea, before during and after the surgery.

Abstract: A laser surgery apparatus including a contact tip comprising an input face having a surface for receiving laser energy from an optical waveguide directed along an axis of propagation. The surface is inclined relative to the axis of propagation such that an angle of incidence between the laser light and the surface is approximately equal to Brewster's angle. Another aspect of the invention includes coating a portion of the tip body with a coating that is reflective to the laser energy. One preferred embodiment comprises a tip body coated with a single coating consisting essentially of a material which is biologically compatible with tissue to prevent generation of a toxic tissue response. A further aspect of the invention includes a tip configuration having a generally conical exterior with a substantially flat surface disposed obliquely to a core axis of the tip body.

Abstract: A medical system for transmitting and delivering to a tissue site multiwavelength therapeutic radiant energy along a common optical pathway. Also included is a laser catheter suitable for engaging multiple sources of laser energy and transmitting multiwavelength therapeutic laser energy along a common optical path for delivery to a worksite.

Abstract: An optically pumped mid-infrared solid-state laser with high pulse repetition rate is described for use in laser surgery. The laser produces a wavelength between 1.7 and 4.0 microns, and is optically pumped. The rise and fall times of the pump pulses are sufficiently short to avoid thermal lensing induced instability. The laser provides an increased rate of tissue cutting without necessitating an increase in the pulse energy.

Abstract: A medical laser apparatus which comprises a medical laser and a waveguide is used to deliver infrared energy to a treatment site. The medical laser preferably delivers electromagnetic radiation at a wavelength of about 3.0 microns such as an Er:YAG laser (wavelength of 2.94 microns). The waveguide comprises a fluoride-based guiding structure surrounding an outer protective structure, and is capable of transmitting invisible infrared light at a wavelength of about 3 microns at a power density of at least about 4 kilowatts per square centimeter. The guiding structure has a core and at least one cladding. The protective structure comprises a jacket of material, preferably polyimide, which is substantially impermeable to moisture and has a moisture resistance significantly higher than that of the guiding structure.

Abstract: A medical system for transmitting and delivering to a tissue site multiwavelength therapeutic radiant energy along a common optical pathway. Also included is a laser catheter suitable for engaging multiple sources of laser energy and transmitting multiwavelength therapeutic laser energy along a common optical path for delivery to a worksite.

Abstract: An optical apparatus functions as a laser catheter for removal, penetration or treatment of human tissue or other biotic material. The arrangement of the optical components, including the focal length of the lens and the spacing between the lens and the source of light is selected to yield an output beam having advantageous characteristics which are particularly suitable for medical laser treatment. Such characteristics include a relatively long beam throw, a long focal range, and a small output beam waist. A hollow tip, preferably conical in shape, is utilized to provide a tactile indicator as to the cutting action of the output beam.

Abstract: A medical system for transmitting and delivering to a tissue site multiwavelength therapeutic radiant energy along a common optical pathway. Also included is a laser catheter suitable for engaging multiple sources of laser energy and transmitting multiwavelength therapeutic laser energy along a common optical path for delivery to a worksite.

Abstract: An endoscope comprising a body, including an elongated tubular distal section adapted for insertion into a patient and optics for transmitting an image through the distal section so that the image can be viewed at a viewing location. The image-transmitting optics include an elongated image-transmitting rod for transmitting the image to at least a region of the distal section. The image-transmitting rod is subject to breakage by bending forces and is divided longitudinally into discrete elongated rod sections to thereby reduce the likelihood of breakage by bending forces.

Abstract: A standing-wave annular laser resonator providing high energy extraction efficiency and good beam quality without the need for polarization coatings. The resonator includes an axicon, a scraper mirror, and a rear mirror system. A critical feature of the configuration is that the axicon has an inner conical mirror of which the apex is offset from the usual position, such that a radial beam reflected from an outer conical mirror has one portion that bypasses the inner mirror without impinging on it. This portion of the radial beam is reflected back along an annular path and makes two more passes through an annular gain region before becoming available for outcoupling around the scraper mirror. The rear mirror system retroreflects and annular beam back on itself in inverted form, without introducing any polarization mixing.

Abstract: A closed cycle chemical laser adapted for continuous wave operation is disclosed. A first gas such as sulphur hexafluoride is decomposed by an electrical discharge means to provide at least some fluorine atoms which when combined with molecular hydrogen in a mixing chamber located upstream of and proximate to an optical power extraction chamber forms an excited laser species capable of stimulated emission to produce a continuous wave output beam. After passing through the optical cavity the effluent is purified by selective absorption and adsorption processes to eliminate the laser species from the effluent and to separate the hydrogen for recirculation back to the mixing chamber. The remaining effluent has its pressure increased, is supplemented with makeup feed gases and is recycled. The operation of the system using sulphur hexafluoride and hydrogen gases is discussed in detail and various combinations of other suitable reactants are disclosed.

Abstract: A variable output resonator is disclosed having a mode control cavity and a power extraction cavity both capable of being independently optimized to produce a laser beam having high power and good optical quality in the far field. A cone having a conical reflective surface is adapted to be linearly moved along a beam axis of the power extraction cavity in the resonator to intercept a portion of the radiation circulating therein to produce the laser beam. Both the diameter and power level of the laser beam are dependent upon the area of the reflective surface of the cone which interacts with the radiation circulating within the resonator. The insertion of the cone into the resonator does not influence the overall resonator alignment since the cone is external to the optical components defining the resonator.

Abstract: A chemical laser having means for repeatedly circulating the gaseous working medium in a portable, self-contained system is disclosed. An excited laser species is formed by chemical means and after passing through the optical cavity, the working medium is purified by selective absorption and adsorption processes, increased in pressure, supplemented with makeup feed reactants and recycled. The operation of a system using deuterium and sulfur hexafluoride gases is discussed in detail although various combinations of other suitable reactants which provide a halogen and hydrogen or an isotope thereof are disclosed.

Abstract: A modification to the reflective surfaces in unstable resonator assemblies to improve the operating characteristics of such devices and enhance the quality in the far field of the output beam from such resonators is disclosed. Some modifications include the elimination of abrupt discontinuities in the reflective surfaces and the forming of an auxiliary unstable resonator along the centerline axis of the primary resonator and result in increased symmetry in the operating characteristics of the system in the gain region and improved intensity profile in the far field for the output beam. The concept is applicable to axial as well as radial flow resonators having either circular or cylindrical optics.

Abstract: A radial flow laser having an unstable resonator configuration with a standing wave optical path is disclosed. The gain medium forms a cylindrical sheath which is symmetric about a centerline axis through the resonator and the output beam is annular in cross section. The resonator geometry is based on a circular end mirror, an annular end mirror, an annular folding mirror having a reflective surface conforming to the inside of a cone geometry and conical folding mirror conforming to the outside of a cone geometry. Various embodiments are disclosed whereby the width of the resonant mode is either held constant or expanded to accommodate various power density loadings on the mirrors. In one configuration, the standing wave travels in a complete loop through the cylindrical sheath of gain medium.

Abstract: Method and apparatus for providing a large fraction of the energy coupling from an unstable resonator in the central lobe of the far field pattern of the output beam from the resonator are disclosed. The resonator is designed to allow a low order mode pattern to resonate about the optical axis therethrough and radiation is coupled out from both the axial region and the outer region of the mode. The geometry of the systems is formed with transmissive and reflective optics in various configurations of linear and ring lasers.

Abstract: A radial flow ring laser having an unstable resonator configuration with a traveling wave optical path is disclosed. The gain medium forms a cylindrical sheath which is symmetric about a centerline axis through the resonator and the output beam is circular in cross section. The resonator geometry is based on first and second conical mirrors which are positioned symmetrically on the axis centerline and first and second annular mirrors which are symmetric about the axis and complete the ring path. The resonator description also includes an annular stripper mirror to produce the output beam of radiation and a suppression mirror to prevent a traveling wave in the undesired direction through the ring. An alternate embodiment includes a cylindrical folding mirror to cause the optical path to cross the centerline axis after each pass through the gain medium.