摘要:
The present invention relates generally to optical waveguides, and more particularly to optical fibers suitable for use with high optical energies, and to devices using them. One aspect of the invention is an optical fiber having a cross-sectional profile comprising a base glass material; a first ring of first low refractive index glass features disposed in the base glass material; and a second ring of second low refractive index glass features disposed in the base glass material outside of and substantially concentric with the first ring, wherein the optical fiber has a loss of less than about 0.7 dB/m for the fundamental mode and a loss greater than about 10 dB/m for all other modes in a coiled configuration having a coil diameter in the range of about 20 cm to about 200 cm.
摘要:
Optical apparatus (110, 500, 600, 800, 1000) for providing light having a selected linear polarization having a polarization ratio, the apparatus (110, 500, 600, 800, 1000) comprising a length of optical fiber (120, 504, 604, 804, 1001) comprising a rare earth for providing light having a first wavelength responsive to receiving pump light having a second wavelength that is different than said first wavelength, wherein if the length of optical fiber (120, 504, 604, 804, 1004) were placed in a first position between the length of fiber (120, 504, 604, 804, 1004) is substantially linearly oriented (20) the fiber (120, 504, 604, 804, 1004) could propagate at the first wavelength a fundamental mode and a plurality of higher order modes and the apparatus (110, 500, 600, 800, 1000) could provide light having a first polarization ratio for the selected linear polarization and an M2 parameter, and wherein the length of fiber (120, 504, 604, 804, 1004) is positioned in a second position that increases the bend loss of the fiber relative to the first position such that, responsive to the increased bend loss, the apparatus (110, 500, 600, 800, 1000) can provide light having a reduced M2 parameter as well as a second polarization ratio for the selected polarization that is increased relative to the first polarization ratio, the increase being at least 6 dB greater than the first polarization ratio, and wherein when the length of fiber (120, 504, 604, 804, 1004) is in the second position the apparatus (110, 500, 600, 800, 1000) can provide a slope efficiency that is at least 50% of the ratio of the second wavelength to the first wavelength.
摘要:
An optical transmission system is provided comprising a thulium doped optical fiber, a light emitting pump device optically coupled to the thulium doped fiber, and a Raman amplifier fiber optically coupled to the thulium doped optical fiber. The light emitting pump device in combination with the thulium doped fiber generates a first amplification pump wavelength and the Raman amplifier receives the first amplification pump wavelength. The first pump wavelength amplifies an optical signal in the Raman amplifier, the Raman amplifier operating at a signal wavelength in the range of about 1530 nm to about 1625 nm.
摘要:
An apparatus and method for thermally tuning an optical amplifier comprises an optical waveguide doped with a fluorescent material, a thermal device for either heating or cooling the optical waveguide, and a pump light for exciting the fluorescent material. The apparatus shapes, shifts, and/or flattens the gain curves of the doped optical amplifier. Thulium doped fiber is cooled to shift the gain curve into the C-band. Erbium doped fiber is heated to flatten the gain curve in the C-band and is cooled to shift the gain curve above the L-band. The apparatus similarly shapes the gain curves of other fluorescent materials. The thermal device comprises three types of optical cooling devices. The apparatus is a component in communications systems, lasers, medical lasers and the like. The method comprises either heating or cooling optical waveguides doped with fluorescent materials to achieve the desired shaping, shifting, and flattening of the gain curves.
摘要:
Disclosed is a substantially transparent glass-ceramic ceramic, and a method for making a glass-ceramic, exhibiting an aluminogallate spinel crystal phase and having a glass-ceramic composition that lies within the SiO2—Ga2O3—Al2O3—K2O—Na2O— system and particularly consisting essentially, in weight percent on an oxide basis, of 25-55% SiO2, 9-50% Ga2O3, 7-33% Al2O3, 0-20% K2O, 0-15% Na2O, 0-6 Li2O and 5-30% K2O+Na2O, the glass ceramic microstructure containing a crystal phase comprising at least 5%, by weight, of aluminogallate spinel crystals. Another aspect disclosed is optical element selected from the group consisting of an optical fiber, a gain or laser medium, and an amplifier component, a saturable absorber, with the element comprising a transparent glass-ceramic of the same composition and containing a crystallinity of at least about 5% by weight of aluminogallate spinel crystals.
摘要:
A Tm-doped germanate glass composition comprises GeO2 having a concentration of at least 20 mole percent, Tm2O3 having a concentration of about 0.001 mole percent to about 2 mole percent, and Ga2O3, having a concentration of about 2 mole percent to about 40 mole percent. The composition can further include an alkaline earth metal compound selected from the group consisting of MgO, CaO, SrO, BaO, BaF2, MgF2, CaF2, SrF2, BaCl2, MgCl2, CaCl2, SrCl2, BaBr2, MgBr2, CaBr2, SrBr2, and combinations thereof, and having a non-zero concentration of less than about 40 mole percent. The composition can further include an alkali metal compound selected from the group consisting of Li2O, Na2O, K2O, Rb2O, Cs2O, Li2F2, Na2F2, K2F2, Rb2F2, Cs2F2, Li2Cl2, Na2Cl2, K2Cl2, Rb2Cl2, Cs2Cl2, Li2Br2, Na2Br2, K2Br2, Rb2Br2, Cs2Br2 and combinations thereof, and having a non-zero concentration of less than about 20 mole percent. The emission bandwidth of the composition in the 1450 nm to 1530 nm range can be varied on the basis of one or more composition ratios. A Tm-doped germanate optical amplifier can amplify optical signals in the S-band region of the electromagnetic spectrum.
摘要翻译:Tm掺杂的锗酸盐玻璃组合物包含浓度为至少20摩尔%的GeO 2,浓度为约0.001摩尔%至约2摩尔%的Tm 2 O 3和浓度为约2摩尔%至约40摩尔%的Ga 2 O 3 。 所述组合物还可以包含选自MgO,CaO,SrO,BaO,BaF 2,MgF 2,CaF 2,SrF 2,BaCl 2,MgCl 2,CaCl 2,SrCl 2,BaBr 2,MgBr 2,CaBr 2,SrBr 2和组合的碱土金属化合物 并且具有小于约40摩尔%的非零浓度。 所述组合物可以进一步包括选自Li 2 O,Na 2 O,K 2 O,Rb 2 O,Cs 2 O,Li 2 F 2,Na 2 F 2,K 2 F 2,Rb 2 F 2,Cs 2 F 2,Li 2 Cl 2,Na 2 Cl 2,K 2 Cl 2,Rb 2 Cl 2,Cs 2 Cl 2,Li 2 Br 2,Na 2 Br 2,K 2 B 2 ,Rb2Br2,Cs2Br2及其组合,并且具有小于约20摩尔%的非零浓度。 1450nm至1530nm范围内的组合物的发射带宽可以基于一种或多种组成比来改变。 Tm掺杂的锗酸盐光放大器可以放大电磁光谱的S带区域的光信号。
摘要:
A method for creating refractive index changes in a substrate is provided by irradiating the substrate with infrared (IR) or visible light radiation. Ultra-violet (UV) radiation is generated in the substrate responsive to the IR or visible light radiation such that the change in the refractive index of the substrate is generated responsive to the UV radiation. Preferably, the substrate comprises a glass doped with rare earth ions.