Abstract: There is provided an optical transmission control device includes a memory, and a processor coupled to the memory and the processor configured to aggregate information of candidacy sections having a possibility that communication is discontinued among wavelength-multiplexed transmission sections, classify, based on the aggregated information, optical paths set between optical transmission devices into a first optical path on which, when communication in the candidacy sections is discontinued, an optical signal is not transmitted, and a second optical path on which, when the communication in the candidacy sections is discontinued, an optical signal is transmitted, and determine a wavelength allocation in a first wavelength group of the first optical path and a second wavelength group of the second optical path so that a difference in gain wavelength characteristics of the first optical path and the second optical path is equal to or less than a predetermined level.

Abstract: There is provided an optical transmission control device includes a memory, and a processor coupled to the memory and the processor configured to aggregate information of candidacy sections having a possibility that communication is discontinued among wavelength-multiplexed transmission sections, classify, based on the aggregated information, optical paths set between optical transmission devices into a first optical path on which, when communication in the candidacy sections is discontinued, an optical signal is not transmitted, and a second optical path on which, when the communication in the candidacy sections is discontinued, an optical signal is transmitted, and determine a wavelength allocation in a first wavelength group of the first optical path and a second wavelength group of the second optical path so that a difference in gain wavelength characteristics of the first optical path and the second optical path is equal to or less than a predetermined level.

Abstract: An optical transmission device includes: a wavelength allocation detector configured to detect wavelength allocation that indicates allocation of optical signals multiplexed in a WDM optical signal; a power adjusting unit configured to adjust powers of the optical signals multiplexed in the WDM optical signal; an optical amplifier configured to amplify the WDM optical signal output from the power adjusting unit; a power controller configured to generate a power control signal to control the power adjusting unit such that the WDM optical signal has a specified wavelength characteristic; and a correction value generator configured to generate a correction value to correct the power control signal based on the wavelength allocation. The power controller corrects the power control signal with the correction value. The power adjusting unit adjusts powers of the optical signals multiplexed in the WDM optical signal according to the corrected power control signal.

Abstract: A Raman amplifier includes: a pump light generator that provides a plurality of pump light beams with different wavelengths for an optical transmission medium; a gain monitor that monitors an average Raman gain in the optical transmission medium; a storage unit that stores ratio information indicating a ratio of power of the plurality of pump light beams for a specified gain characteristic with respect to an average Raman gain in the optical transmission medium; and a controller that controls the power of the plurality of pump light beams based on the average Raman gain monitored by the gain monitor and the ratio information.

Abstract: Disclosed is an ultraviolet and infrared absorptive glass characterized by that its coloring component contains, based on mass of the ultraviolet and infrared absorptive glass, 0.05-0.9 mass % of CeO2, 0.50-1.20 mass % of of total iron oxide in terms of Fe2O3, 0.08-0.30 mass % of FeO, 0.1-1.5 mass % of TiO2, 10-25 mass ppm of CoO, and 0.1-50 mass ppm of Cr2O3, that mass ratio (Fe2+/Fe3+) of divalent iron to trivalent iron is 0.20-0.45, and that dominant wavelength measured by using illuminant D65 of JIS Z 8701 is 510-560 nm. This glass has satisfactory optical characteristics, even though the content of CeO2 has been reduced.

Abstract: The present invention aims to provide a chemically strengthened glass plate which has a good yield in a cutting process of the chemically strengthened glass plate and has sufficient strength. The chemically strengthened glass plate has a surface compressive stress of not less than 600 MPa at a surface of the chemically strengthened glass plate, and a compressive stress layer containing two types of stress patterns A and B. The stress pattern A is a stress pattern of a surface portion of the glass plate, and the stress pattern B is a stress pattern of an inside of the glass plate. The stress patterns satisfy the formula SA>SB where SA represents a slope of the stress pattern A and SB represents a slope of the stress pattern B when the stress patterns A and B are each approximated by a linear function.

Abstract: A Raman amplifier includes: a pump light generator that provides a plurality of pump light beams with different wavelengths for an optical transmission medium; a gain monitor that monitors an average Raman gain in the optical transmission medium; a storage unit that stores ratio information indicating a ratio of power of the plurality of pump light beams for a specified gain characteristic with respect to an average Raman gain in the optical transmission medium; and a controller that controls the power of the plurality of pump light beams based on the average Raman gain monitored by the gain monitor and the ratio information.

Abstract: An optical transmission apparatus includes an optical amplifier configured to amplify a wavelength-division multiplexed signal light using an amplifying medium doped with a rare earth ion, a first optical transmitter configured to output a wavelength of a dual-polarization-multiplexed signal to a short wavelength side of an amplification band of the optical amplifier, a second optical transmitter configured to output a wavelength of a non polarization-multiplexed signal to a long wavelength side of the amplification band of the optical amplifier, and an optical multiplexer configured to input a wavelength-division multiplexed signal to the optical amplifier, the wavelength-division multiplexed signal comprising the non polarization-multiplexed signal and the dual-polarization-multiplexed signal.

Abstract: In an optical amplification apparatus an optical amplifier amplifies an optical signal at set gain. An equalizer changes loss of the amplified optical signal according to wavelengths. A processor controls the equalizer so as to make the equalizer have a loss-wavelength characteristic corresponding to a gain tilt of the optical amplifier which occurs according to the set gain.

Abstract: There is provided an optical transmission apparatus including: a transmitter to output an optical signal to be transferred to other optical transmission apparatus; a first dummy light source to generate first dummy light having a wavelength which is not included in an optical signal received from other optical transmission apparatus; a first wavelength-multiplexer to wavelength-multiplex the optical signal received from other optical transmission apparatus, the optical signal output from the transmitter, and an optical signal with a wavelength, of the first dummy light, which is not included in the optical signal received from other optical transmission apparatus and in the optical signal output from the transmitter; and an optical amplifier to amplify an optical signal multiplexed by the first wavelength-multiplexer.

Abstract: The present invention aims to provide a chemically strengthened glass with cutting easiness and a higher compressive residual stress than the conventional one, made of soda-lime glass. The chemically strengthened glass of the present invention is a chemically strengthened glass manufactured by ion exchange of a surface layer of a glass article to replace alkali metal ions A which are the largest in amount among all the alkali metal ion components of the glass article with alkali metal ions B having a larger ionic radius than the alkali metal ions A, wherein the glass article before the ion exchange is made of soda-lime glass substantially composed of SiO2: 65 to 75%, Na2O+K2O: 5 to 20%, CaO: 2 to 15%, MgO: 0 to 10%, and Al2O3: 0 to 5% on a mass basis, the chemically strengthened glass after the ion exchange has a surface compressive stress of 600 to 900 MPa, and has a compressive stress layer with a depth of 5 to 20 ?m at a surface of the glass.

Abstract: The present invention aims to provide a chemically strengthened glass plate which has a good yield in a cutting process of the chemically strengthened glass plate and has sufficient strength. The chemically strengthened glass plate has a surface compressive stress of not less than 600 MPa at a surface of the chemically strengthened glass plate, and a compressive stress layer containing two types of stress patterns A and B. The stress pattern A is a stress pattern of a surface portion of the glass plate, and the stress pattern B is a stress pattern of an inside of the glass plate. The stress patterns satisfy the formula SA>SB where SA represents a slope of the stress pattern A and SB represents a slope of the stress pattern B when the stress patterns A and B are each approximated by a linear function.

Abstract: The present invention aims to provide a cover glass for display devices, made of soda-lime glass, excellent in cutting easiness and reliability of surface strength. The cover glass for display devices of the present invention includes a chemically strengthened glass, and has a compressive stress layer having a depth of 6 to 15 ?m. In the cover glass, a shape parameter determined in accordance with JIS R 1625 (1996) based on analysis of a facture stress of the cover glass measured by a coaxial double ring test is not less than 7, and strength of the cover glass when a cumulative fracture probability is 1% is not less than 450 MPa. The glass plate before the ion exchange is made of soda-lime glass.

Abstract: Disclosed is a glass with low solar transmittance, which is characterized by that it has a basic composition of soda-lime-silica glass, that it contains as coloring components 0.70-1.70 mass % of Fe2O3 (total iron in terms of ferric iron), 0.15-0.45 mass % of FeO (ferrous iron), 0-0.8 mass % of TiO2, 100-350 ppm of CoO, 0-60 ppm of Se, 100-700 ppm of Cr2O3, and 3-150 ppm of MnO, that it has a ratio (Fe2+/Fe3+) of ferrous iron to ferric iron of 0.20-0.80. This glass has superior ultraviolet absorbing performance and infrared absorbing performance (heat insulation performance) and an appropriate transparency.

Abstract: Disclosed is an ultraviolet and infrared absorptive glass characterized by that its coloring component contains, based on mass of the ultraviolet and infrared absorptive glass, 0.05-0.9 mass % of CeO2, 0.50-1.20 mass % of of total iron oxide in terms of Fe2O3, 0.08-0.30 mass % of FeO, 0.1-1.5 mass % of TiO2, 10-25 mass ppm of CoO, and 0.1-50 mass ppm of Cr2O3, that mass ratio (Fe2+/Fe3+) of divalent iron to trivalent iron is 0.20-0.45, and that dominant wavelength measured by using illuminant D65 of JIS Z 8701 is 510-560 nm. This glass has satisfactory optical characteristics, even though the content of CeO2 has been reduced.

Abstract: A dispersion compensating apparatus includes a tunable dispersion compensator that dispersion-compensates an optical signal using a group delay property that is asymmetrical in bands outside an effective band; a set device that sets a dispersion compensation amount in the tunable dispersion compensator; and a shifter that shifts a central frequency of the effective band of the tunable dispersion compensator, based on the dispersion compensation amount set by the set device.

Abstract: Disclosed is a glass with low solar transmittance, which is characterized by that it has a basic composition of soda-lime-silica glass, that it contains as coloring components 0.70-1.70 mass % of Fe2O3 (total iron in terms of ferric iron), 0.15-0.45 mass % of FeO (ferrous iron), 0-0.8 mass % of TiO2, 100-350 ppm of CoO, 0-60 ppm of Se, 100-700 ppm of Cr2O3, and 3-150 ppm of MnO, that it has a ratio (Fe2+/Fe3+) of ferrous iron to ferric iron of 0.20-0.80. This glass has superior ultraviolet absorbing performance and infrared absorbing performance (heat insulation performance) and an appropriate transparency.

Abstract: In an optical amplification apparatus an optical amplifier amplifies an optical signal at set gain. An equalizer changes loss of the amplified optical signal according to wavelengths. A processor controls the equalizer so as to make the equalizer have a loss-wavelength characteristic corresponding to a gain tilt of the optical amplifier which occurs according to the set gain.

Abstract: There is provided an optical transmission apparatus including: a transmitter to output an optical signal to be transferred to other optical transmission apparatus; a first dummy light source to generate first dummy light having a wavelength which is not included in an optical signal received from other optical transmission apparatus; a first wavelength-multiplexer to wavelength-multiplex the optical signal received from other optical transmission apparatus, the optical signal output from the transmitter, and an optical signal with a wavelength, of the first dummy light, which is not included in the optical signal received from other optical transmission apparatus and in the optical signal output from the transmitter; and an optical amplifier to amplify an optical signal multiplexed by the first wavelength-multiplexer.

Abstract: An optical amplifier includes an optical signal path that optically couples an input port and an output port, and transmits an optical signal input from the input port to the output port; an optical amplification medium that is arranged in the optical signal path, and amplifies the optical signal in a predetermined amplification wavelength band; and an optical filter that is arranged between the optical amplification medium and the output port in the optical signal path, flattens gain wavelength characteristics of the optical amplification medium in the amplification wavelength band, and attenuates amplified spontaneous emission (ASE) at a center of the amplification wavelength band more greatly than ASE at both sides of the amplification wavelength band among ASE that occurs in the optical amplification medium on the optical signal amplified by the optical amplification medium.