Abstract: An optical monitoring apparatus based on the scanning of the gain profile of erbium-doped fiber amplifiers (EDFA) and applied in a wavelength division multiplexing network has been proposed and experimentally demonstrated. The EDFA with an injected saturated tone can provide variable gain or loss profile by controlling the pump power. The components used in the present optical monitoring apparatus for use in a wavelength division multiplexing network are easily available and cost-effective, valuable for monitoring frequency and power of a WDM optical communication system, and capable of greatly enhancing resolution of monitoring frequency spectrum for the optical fiber network system.

Abstract: The invention relates to a laser system using a multi-longitudinal-mode Fabry-Perot laser diode as an inter-injection light source and a gain cavity formed by other laser diodes of such type so as to achieve the function of fast wavelength switching, so that it is possible to achieve repetitively fast switching of wavelength by varying and controlling the bias voltage of maximum optical gain in said inter-injection type multi-longitudinal-mode Fabry-Perot laser diode so as to achieve three different wavelengths with tuning range of 3.5 nm for a side-mode suppression ratio (SMSR) greater than 19 dB and a response time of wavelength switching in the order of nanosecond.

Abstract: An optical monitoring apparatus based on the scanning of the gain profile of erbium-doped fiber amplifiers (EDFA) and applied in a wavelength division multiplexing network has been proposed and experimentally demonstrated. The EDFA with an injected saturated tone can provide variable gain or loss profile by controlling the pump power. The components used in the present optical monitoring apparatus for use in a wavelength division multiplexing network are easily available and cost-effective, valuable for monitoring frequency and power of a WDM optical communication system, and capable of greatly enhancing resolution of monitoring frequency spectrum for the optical fiber network system.

Abstract: A method for producing metal sputtering target, comprising a step of double V melting process, and a step of high temperature forging. The step of double V melting process produces a single metal of aluminum, titanium, or copper, or an alloy of the single metal associated with at least a different metal selecting from one of copper, silicon, titanium, zirconium, osmium, molybdenum, tungsten, platinum, gold, niobium, tantalum, cobalt, rhenium, and scandium. The step of high temperature forging treats the single metal or the alloy to form the metal sputtering target material with small crystal grains and a secondary phase of fineness and high homogeneity suitable for using in semiconductor and photoelectric industries.