Abstract: A method of transferring energy in an optical fiber (12) from the fiber's cladding element (16) of the fiber's core element (14) is disclosed. The core element (14) includes an active gain component and an energy migration component, and the cladding element (16), which surrounds the core element (14), includes the energy migration component. The method includes the steps of providing a pump (22) for producting energy and optically coupling the pump with the cladding element (16), such that the energy is absorbed and stored in the cladding element (16) by its energy migration component. A further step includes the active gain component in the core element (14) lasing or providing gain, when the transferring of energy from the cladding element's energy migration component to the core element's energy migration component takes place.

Abstract: An optical fiber laser structure and system are disclosed. The fiber laser structure includes a core, an inner cladding, and an outer cladding. The core has a first and second end and includes a combination of ytterbium and erbium as a first active gain component. The inner cladding, having a length defined between the first and second ends, surrounds the core. The inner cladding includes neodymium as a second active gain component that is different from the first active gain component. The system includes a pumping source coupled to the inner cladding to provide energy to the neodymium in the inner cladding. Upon being pumped, the neodymium achieves amplified spontaneous emission in the inner cladding along the length between the first and second ends. As a result, energy is efficiently transferred from the neodymium to the combination of the ytterbium and erbium in the core thereby providing laser activity at an eye-safe laser wavelength of 1535 nanometers.

Abstract: A high-gain phosphate glass composition, which can be used to produce ultra-short gain length lasers and optical amplifiers is described wherein the composition of the glass in addition to exhibiting high gain for lasers and amplifiers, also exhibits high thermal shock resistance, high cross section, insignificant concentration quenching, and high solubility for rare earth ions and other properties which enable the material to be fabricated into a new class of ultra-short length micro-laser, fiber laser and amplifier configurations and designs.

Abstract: A composition of phosphate-based glass fiber capable of being fused directly to a silica-based glass fiber includes from about 60 mole % to about 75 mole % P2O5, from about 8 mole % to about 30 mole % X203, from about 0.01 mole % to about 25 mole % of R2O. X is selected from the group of Al, B, La, Sc, Y and combinations thereof. R is selected from the group of Li, Na, K and combinations thereof. Optionally, the phosphate-based glass fiber may include 0.5 to 10 mole % MO, where M is selected from Mg, Ca, Sr, Ba, Zn, and combinations thereof. The composition preferably further includes from about 0.5 mole % to about 15 mole % of an additional component from the group of Si, Ge, Pb, Te and combinations thereof.

Abstract: A new multi-component optical amplifier glass, composed of multiple glass formers has been developed which displays bandwidths significantly larger than currently possible using silica-based or phosphate based, erbium doped fibers. Initial results indicate that using this material, one could double the bandwidth of existing optical amplifiers. This greatly increased spectrum combined with higher emission cross sections and the ability to go to higher doping concentrations, compared with silica-based fibers, make this new optical amplifier very attractive for increasing the transmission capacity of wavelength-division-multiplexing (WDM) transmission systems using optical fibers.

Abstract: An optical fiber laser structure and system are disclosed. The fiber laser structure includes a core, an inner cladding, and an outer cladding. The core has a first and second end and includes a combination of ytterbium and erbium as a first active gain component. The inner cladding, having a length defined between the first and second ends, surrounds the core. The inner cladding includes neodymium as a second active gain component that is different from the first active gain component. The system includes a pumping source coupled to the inner cladding to provide energy to the neodymium in the inner cladding. Upon being pumped, the neodymium achieves amplified spontaneous emission in the inner cladding along the length between the first and second ends. As a result, energy is efficiently transferred from the neodymium to the combination of the ytterbium and erbium in the core thereby providing laser activity at an eye-safe laser wavelength of 1535 nanometers.

Abstract: A system for determining the optimal circuit design simulator schedule for debugging a digital electronic circuit design. The system characterizes all available circuit design simulators in terms of several parameters reflecting simulator speed and the time required to discover, isolate and fix a design error (bug). A cutover point is established for any pair of available simulators on the basis of these parameters. One simulator is progressively more efficient than the other beyond this cutover point, which is the desired time for scheduling substitution of the more efficient simulator during the debugging process. The system also permits "what-if" evaluation of alternative debugging strategies in advance by creating alternative schedules in response to various characteristic parameters.

Abstract: H.sub.2 S is removed from a fluid stream by contacting the stream with an aqueous solution having at least two components: an effective amount of an iron (III) chelate to oxidize H.sub.2 S to sulfur and, an amount of a water soluble anionic polymer containing sulfonic acid groups, carboxyl groups or mixtures thereof which is effective to stabilize the chelate. During the removal process the iron chelate is reduced to iron(II) chelate, and sulfur particles are produced.

Abstract: Phosphate glass compositions which exhibit both athermal behavior under high thermal loading and high thermal shock resistance without special conditioning. High gain, laser rods, discs and other optical elements formed of these phosphate glass compositions are also described.

Abstract: Ion-exchangeable phosphate glass compositions containing in mole percent from about 50 to 70% P.sub.2 O.sub.5, from about 5 to 30% Li.sub.2 O, from about 5 to 25% MO, where M is selected from the group consisting of Be, Mg, Ca, Sr, Ba, and Zn, and about 5 to 30% X.sub.2 O.sub.3, where X is selected from the group consisting of Al, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu are provided. In another aspect, the phosphate glass compositions of the present invention also contain in mole percent up to 10% R.sub.2 O, where R is selected from the group consisting of Na, K, Rb and Cs. Solarization inhibitors and minor amounts of anhydrous fluorides and chlorides are also included in some embodiments. Optical quality phosphate glass articles formed of the phosphate glass compositions of the present invention are readily ion- exchangeable when contacted with certain salts. Optical quality phosphate glass articles are also provided having good thermal shock resistance.

Abstract: Ion-exchangeable phosphate glass compositions containing in mole percent from about 50 to 70% P.sub.2 O.sub.5, from about 5 to 30% Li.sub.2 O, from about 5 to 25% MO, where M is selected from the group consisting of Be, Mg, Ca, Sr, Ba, and Zn, and about 5 to 30% X.sub.2 O.sub.3, where X is selected from the group consisting of Al, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu are provided. In another aspect, the phosphate glass compositions of the present invention also contain in mole percent up to 10% R.sub.2 O, where R is selected from the group consisting of Na, K, Rb and Cs. Solarization inhibitors and minor amounts of anhydrous fluorides and chlorides are also included in some embodiments. Optical quality phosphate glass articles formed of the phosphate glass compositions of the present invention are readily ion-exchangeable when contacted with certain salts. Optical quality phosphate glass articles are also provided having good thermal shock resistance.

Abstract: Phosphate laser glass compositions which include erbium ions as the active laser ion material. In one aspect, ytterbium, chromium and cerium ions are present as auxiliary dopants. The ytterbium, chromium and cerium additives serve to sensitize the erbium-doped phosphate glasses of the present invention. The glasses are particularly useful in applications where an "eye-safe" wavelength is desirable.

Abstract: Ion-exchangeable phosphate glass compositions containing in mole percent from about 50 to 70% P.sub.2 O.sub.5, from about 5 to 30 % Li.sub.2 O, from about 5 to 25% MO, where M is selected from the group consisting of Be, Mg, Ca, Sr, Ba, and Zn, and about 5 to 30% X.sub.2 O.sub.3, where X is selected from the group consisting of Al, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu are provided. In another aspect, the phosphate glass compositions of the present invention also contain in mole percent up to 10% R.sub.2 O, where R is selected from the group consisting of Na, K, Rb and Cs. Solarization inhibitors and minor amounts of anhydrous fluorides and chlorides are also included in some embodiments. Optical quality phosphate glass articles formed of the phosphate glass compositions of the present invention are readily ion- exchangeable when contacted with certain salts. Optical quality phosphate glass articles are also provided having good thermal shock resistance.

Abstract: A method of removing hydrogen sulfide from a gaseous stream in a contact zone by contacting the gaseous stream with an aqueous alkaline scrubbing solution containing a polyvalent metal chelate at a pH of about 7 to about 10 wherein the polyvalent metal chelate is in one embodiment all or substantially all in the reduced or lower valence state in a contact zone and is oxidized to the oxidized or higher valence state in an oxidation zone so as to convert hydrosulfide and/or sulfide salts present in the contact zone to sulfur. In a second embodiment the aqueous alkaline solution contacting the gaseous stream is a mixture containing higher and lower valence polyvalent metal chelates.

Abstract: A sensitized laser glass which includes a primary lasing dopant and auxiliary dopants which absorb in regions of the flashlamp emission spectrum away from the absorption bans of the primary dopant and transfer the energy absorbed to the primary dopant, thus improving the efficiency and sensitivity of the laser glass. The auxiliary dopant comprises the combination of cerium and chromium as Ce.sub.2 O.sub.3 and Cr.sub.2 O.sub.3 and the primary dopant is a rare earth metal, preferably neodymium or erbium as Nd.sub.2 O.sub.3 or Er.sub.2 O.sub.3. Th auxiliary dopant consists essentially of 0.1 to 5% by weight Ce.sub.2 O.sub.3 and 0.025 to 0.1% by weight Cr.sub.2 O.sub.3, however the preferred concentration of the auxiliary dopant is 2 to 4% by weight Ce.sub.2 O.sub.3 plus 0.03 to 0.07% by weight Cr.sub.2 O.sub.3. The experimental data establishes that such auxiliary dopants are particularly suitable for phosphate laser glasses.

Abstract: A simplified, relatively inexpensive laser device, wherein the laser elements are fixed in a body exoskeleton of electrical insulating material having a low coefficient of thermal expansion. The preferred embodiment includes a shotgun type laser filter having parallel bores which receive the laser flashlamp and laser rod in fixed relation in a body chamber. The reflector surrounds the laser filter and retains the filter within the body chamber. In the preferred method of this invention, several controlled lasing pulses are generated with each illumination pulse of the flashlamp, substantially increasing the efficiency of the laser device. The number of pulses is generally controlled by increasing the voltage to the flashlamp. The rapid multiple lasing pulses generate an elongated plasma in a fluid medium, such as the vitreous fluid body of an eye which makes the laser device extremely efficient for treating glaucoma and other medical treatments.

Abstract: A simplified, relatively inexpensive laser device, wherein the laser elements are fixed in a body exoskeleton of electrical insulating material having a low coefficient of thermal expansion. The preferred embodiment includes a shotgun type laser filter having parallel bores which receive the laser flashlamp and laser rod in fixed relation in a body chamber. The reflector surrounds the laser filter and retains the filter within the body chamber. In the preferred method of this invention, several controlled lasing pulses are generated with each illumination pulse of the flashlamp, substantially increasing the efficiency of the laser device. The number of pulses is generally controlled by increasing the voltage to the flashlamp. The rapid multiple lasing pulses generate an elongated plasma in a fluid medium, such as the vitreous fluid body of an eye which makes the laser device extemely efficient for treating glaucoma and other medical treatments.

Abstract: A phosphate laser glass in which the optical path length is substantially independent of temperature, or "athermal", particularly under rapid pulsing, and chemically stable, while providing high gain. The base glass composition comprises, in mole percent, 55 to 70% P.sub.2 O.sub.5, 3 to 15% of an alkali metal oxide, preferably Li.sub.2 O plus K.sub.2 O, 20 to 30% BaO and 0.5 to 5% Al.sub.2 O.sub.3. Up to 15% of the BaO may be replaced by CaO, SrO or MgO and part of the Al.sub.2 O.sub.3 may be replaced by Nd.sub.2 O.sub.3. The total Al.sub.2 O.sub.3 plus Nd.sub.2 O.sub.3 is 4 mole percent .+-.1.5%. The laser glass composition also includes a laseable component, preferably Nd.sub.2 O.sub.3 and preferably includes a solarization inhibitor.

Abstract: Laser phosphate glass compositions are provided by combining constituent elements at defined amounts to form compositions which provide a balance of properties to the glass, especially high gain and low n.sub.2.