Abstract: A cladding-pumped fiber structure, suitable for use as a laser, provides for efficient clad-to-core energy transfer. The outside interface of the pump-clad is constructed from a rod-shaped preform by local melt-displacement using an open flame.

Abstract: A suture anchor is described which in one form may be easily fabricated from extruded material by angular cuts and bore holes which provide an offset pulling force to the suture. In an alternate and preferred embodiment the suture anchor is injection molded having an annular displaced corner and abutment wall which act to seat the suture anchor firmly within a bore hole. Novel application means are also disclosed which hold the suture anchor on a frangible shaft for insertion and upon completion of the insertion permit fracture of the frangible portion and removal of the instrument.

Abstract: A cladding-pumped fiber structure is disclosed in which mode mixing of pump light injected into the fiber is induced by index modulation. In one embodiment, the index modulation is created by a stress-inducing region disposed in the cladding which simultaneously maintains the polarization within the core to produce a polarization-maintaining fiber useful for multi-mode and laser applications.

Abstract: The specification describes fiber laser devices with cores containing aluminum in which the composition of the core is modified to minimize the core .DELTA., thereby allowing a larger core diameter, and a reduction in the fiber laser length by a factor equal to the square of the diameter difference. This result is achieved by compensation doping the core with phosphorus to offset the index-modifying contribution of aluminum.

Abstract: An optical fiber amplifier is pumped by a fiber pump laser which has a pair of separate active media within a common resonator. The fiber gain section of the amplifier is also located within the resonator.

Abstract: Optical fiber according to the invention comprises a core, with an inner cladding surrounding the core, and an outer cladding surrounding the inner one. The fiber comprises preform-derived glass. The outer cladding comprises a first outer cladding region between the inner cladding region and a second outer cladding region. The first outer cladding region is selected to have an effective refractive index less than 1.35, and such that the optical characteristics of the optical fiber are essentially independent of the second outer cladding, and/or such that the fiber is re-coat insensitive. The first outer cladding typically comprises elongate features extending in the fiber axial direction, with a web material joining the inner cladding to the second outer cladding. The elongate features are filled with a low-index material, exemplarily air, but could of course be evacuated. Fibers according to the invention have many uses, e.g., cladding-pumped optical fiber or fiber with a long period grating.

Abstract: A cladding-pumped fiber structure, suitable for use as a laser, provides for efficient clad-to-core energy transfer. The outside interface of the pump-clad is constructed from a rod-shaped preform by local melt-displacement using an open flame.

Abstract: The specification describes a process and apparatus for monitoring and controlling the ellipticity of preform tubes during Modified Chemical Vapor Deposition. In response to computer generated signals from the monitoring device, the tube collapse rate is adjusted dynamically by locally changing the temperature of the glass tube, or by changing the physical force acting to collapse the tube.

Abstract: In accordance with the invention, light is coupled from a plurality of semiconductor emitters to a cladding-pumped fiber via tapered fiber bundles fusion spliced to the cladding-pumped fiber. Individual semiconductor broad stripe emitters can be coupled to individual multimode fibers. The individual fibers can be bundled together in a close-packed formation, heated to melting temperature, drawn into a taper and then fusion spliced to the cladding-pumped fiber. Advantageously, the taper is then overcoated with cladding material such as low index polymer. In addition, a fiber containing a single-mode core can be included in the fiber bundle. This single-mode core can be used to couple light into or out of the single-mode core of the cladding-pumped fiber.

Abstract: Disclosed are non-periodic microstructured optical fibers that guide radiation by index guiding. By appropriate choice of core region and cladding region, the effective refractive index difference .DELTA. between core region and cladding can be made large, typically greater than 5% or even 10 or 20%. Such high .DELTA. results in small mode field diameter of the fundamental guided mode (typically<2.5 .mu.m), and consequently in high radiation intensity in the core region. Exemplarily, a fiber according to the invention has a solid silica core region that is surrounded by an inner cladding region and an outer cladding region. The cladding regions have capillary voids extending in the axial fiber direction, with the voids in the outer cladding region having a larger diameter than those in the inner cladding region, such that the effective refractive index of the outer cladding region is greater than that of the inner cladding region. Non-periodic microstructured fiber potentially has many uses, e.g.

Abstract: Multistage Er-doped fiber amplifiers (EDFAs) are disclosed. They comprise a first stage that comprises Er and Al, and further comprise a second stage that comprises Er and a further rare earth element, exemplary Yb. Such multistage EDFAs can have advantageous characteristics e.g., a relatively wide flat gain region (e.g. 1544-1562 nm), and relatively high output power, without significant degradation of the noise figure. Exemplary, the amplifiers are used in WDM systems and in analog CATV systems.

Abstract: A cladding pumped optical fiber laser comprises a length of optical fiber having a rare earth-doped region of diameter d.sub.RE >d.sub.01 where d.sub.01 is the mode diameter of the LP.sub.01 mode of the fiber at the laser radiation at wavelength .lambda.. In one embodiment the fiber has a core diameter d.sub.c selected such that the LP.sub.01 mode is the only guided spatial mode of the fiber, and d.sub.RE is greater than d.sub.c. In another embodiment the fiber supports at least one higher order guided spatial mode, typically LP.sub.11 or LP.sub.02, and d.sub.RE is approximately equal to or larger than d.sub.c. Currently preferred embodiments comprise a grating-defined laser cavity that comprises a mode-coupling refractive index grating. Cladding pumped lasers according to the invention will typically have efficient conversion of pump radiation to laser radiation, and consequently can typically be shorter than analogous prior art cladding pumped lasers.

Abstract: Applicants have determined that the temperature sensitivity of long-period grating devices is due to differential variation with temperature of the refractive indices of the core and cladding. They have further determined that the cladding profile and fiber composition can be redesigned to substantially reduce this differential variation, thereby reducing the temperature sensitivity of long-period gratings of less than 4 nm per 100.degree. C. and preferably less than 2 nm per 100.degree. C. This design permits the use of long-period grating devices without temperature control or compensation.

Abstract: In an optical fiber light source a section of multimode fiber is interposed between an energizing laser (e.g,, a diode laser) and a single mode fiber active medium. In a preferred embodiment the single mode fiber active medium is surrounded by a multimode cladding coupled to the multimode fiber. The source may serve as a pump laser for a fiber amplifier or as an amplified spontaneous emission source. Arrangements for coupling several energizing lasers to the active medium are also described.

Abstract: A suture anchor having an anchor member, a central shaft and outwardly extending wing members. A suture mounting hole is provided in the suture anchor for receiving a surgical suture. The suture anchor is inserted into a bore hole in a bone as part of an orthopedic surgical procedure wherein soft tissue such as a tendon is attached to the surface of the bone. Optionally, bone tissue may be attached to the surface of the bone. The wings may have cutting edges or piercing points. The suture anchors may have screw threads on their outer surfaces.

Abstract: An intracorporeal knot tying device. The knot tying device comprises a cannula tube having a proximal end and a distal end and passage therethrough. A suture is movably mounted within the tubular passage. A needle is mounted to the distal end of the suture. The cannula has in its distal end a slit or a distally extending arm for retaining the suture and maneuvering the suture while tying an intracorporeal knot.

Abstract: An apparatus for housing, feeding and applying multiple ligating clips, including a handle which houses a delivery and feeding mechanism, and a cartridge which holds the clips. The handle employs a scissors-type action to set a clip which has been delivered to the jaws by the feeding and ratcheting mechanism. The feeding mechanism provides a relatively long stroke motion to deliver a clip from the end of a cartridge to the end of the nose. The mechanism also provides a relatively short stroke motion for operating the ratchet mechanism of the cartridge for feeding clips through the cartridge. The feeding, ratcheting and setting of the clip is all done by a single, scissors-type action employing only a small motion envelope so that the overall shape of the handle may be small and compact and readily adaptable for use deep in an incision site. The cartridge includes a fixed and moving ratchet rack which are operated by the short stroke ratcheting mechanism of the handle.

Abstract: An actuating mechanism is provided for a hand-operated surgical instrument having at least one operating member. The operating member is engaged by or extends from a flexible pusher member wound at least partially around the circumference of a drum and secured thereto. A pinion is connected to the drum for rotation therewith and is driven by a gear segment on a handle that is pivotally monted to the instrument. A full stroke compelling mechanism is associated with the drum for preventing return of the handle to the unactuated position unless and until the operating member has been moved through the full design range of movement.

Abstract: An apparatus for housing, feeding and applying multiple ligating clips, including a handle which houses a delivery and feeding mechanism, and a cartridge which holds the clips. The handle employs a scissors-type action to set a clip which has been delivered to the jaws by the feeding and ratcheting mechanism. The feeding mechanism provides a relatively long stroke motion to deliver a clip from the end of a cartridge to the end of the nose. The mechanism also provides a relatively short stroke motion for operating the ratchet mechanism of the cartridge for feeding clips through the cartridge. The feeding, ratcheting and setting of the clip is all done by a single, scissors-type action employing only a small motion envelope so that the overall shape of the handle may be small and compact and readily adaptable for use deep in an incision site. The cartridge includes a fixed and moving ratchet rack which is operated by the short stroke ratcheting mechanism of the handle.