Abstract: Disclosed are a device and a method for microelectrodeposition through a laser assisted flexible following tool electrode. Localization of electrodeposition and dimensional precision of members are enhanced by using the flexible following tool electrode to restrict a dispersion region of an electric field and a reaction region of electrodeposition, and a complex-shaped member can be deposited by controlling a motion path of the flexible following tool electrode. Since a laser has a high power density, introducing laser irradiation changes an electrode state in a radiated region, accelerates ion diffusion and electron transfer speeds, and increases a deposition rate, thus reducing defects such as pitting and cracking in a deposit, enhancing deposition quality, and achieving fabrication of a micro-part by a synergistic action of both electrochemical energy and laser energy.

Abstract: An apparatus for micromachining a semiconductor material from opposing sides through synchronous coordination of laser and electrochemistry includes an optical path system, a stable low-pressure jet generation system, and an electrolytic machining system. The optical path system includes a laser generator, a beam expander, a reflector, a galvanometer, and a lens. The electrolytic machining system includes a direct-current pulsed power supply, an adjustable cathode fixture, an electrolyte tank, a current probe, and an oscilloscope. The stable low-pressure jet generation system provides an electrolyte flow into a metal needle. The electrolyte flow forms an electrolyte layer between a semiconductor material and a cathode copper plate, such that the cathode and the anode are in electrical contact with each other. In a method employing the apparatus, a laser beam is irradiated onto the semiconductor material to form a local high-temperature region, which leads to a localized increase in electrical conductivity.

Abstract: Disclosed are a device and a method for microelectrodeposition through a laser assisted flexible following tool electrode. Localization of electrodeposition and dimensional precision of members are enhanced by using the flexible following tool electrode to restrict a dispersion region of an electric field and a reaction region of electrodeposition, and a complex-shaped member can be deposited by controlling a motion path of the flexible following tool electrode. Since a laser has a high power density, introducing laser irradiation changes an electrode state in a radiated region, accelerates ion diffusion and electron transfer speeds, and increases a deposition rate, thus reducing defects such as pitting and cracking in a deposit, enhancing deposition quality, and achieving fabrication of a micro-part by a synergistic action of both electrochemical energy and laser energy.

Abstract: An apparatus for micromachining a semiconductor material from opposing sides through synchronous coordination of laser and electrochemistry includes an optical path system, a stable low-pressure jet generation system, and an electrolytic machining system. The optical path system includes a laser generator, a beam expander, a reflector, a galvanometer, and a lens. The electrolytic machining system includes a direct-current pulsed power supply, an adjustable cathode fixture, an electrolyte tank, a current probe, and an oscilloscope. The stable low-pressure jet generation system provides an electrolyte flow into a metal needle. The electrolyte flow forms an electrolyte layer between a semiconductor material and a cathode copper plate, such that the cathode and the anode are in electrical contact with each other. In a method employing the apparatus, a laser beam is irradiated onto the semiconductor material to form a local high-temperature region, which leads to a localized increase in electrical conductivity.

Abstract: The disclosure relates to a fast, stable method of output wavelength control in a DWDM optical device, and a circuit configured to perform the method. The method and circuit can control timing and overshoot during conditions of rapid operational changes, such as during power-on or restart of the device. The method and circuit includes optimized APC, TEC and electro-absorption (EA) modulator control hardware and algorithms, to effectively control transient processes. Software and circuitry based on the method(s) are achieved in part by optimizing APC, EA and TEC control algorithms. In combination with hardware/circuit optimization, one can achieve fast turn-on of an optical output signal at a stable wavelength. The method and circuit provides a stable power-up process in which a change of wavelength is small enough to meet DWDM specification requirements, to ensure the elimination and avoidance of crosstalk in adjacent channels in dense wave (sub)systems.

Abstract: The disclosure relates to a fast and stable method of output wavelength control in a DWDM optical device, and a circuit configured to perform the method. The method and circuit can control of timing and overshoot during conditions of rapid operational changes, such as during power-on or restart of the device. The method and circuit includes optimized APC, TEC and electro-absorption (EA) modulator control hardware and algorithms, to effectively control transient processes. In the present disclosure, software and circuitry based on the method(s) are achieved in part by optimizing APC, EA and TEC control algorithms. The present disclosure combines low-cost methodology and hardware. In combination with hardware/circuit optimization, one can achieve fast turn-on of an optical output signal at a stable wavelength.

Abstract: A tuned absorber (5A, 5B) for attachment to a railway rail (1) comprises a body (6) formed of elastomeric material and of at least one region of a first material, denser than the elastomeric material, located within the elastomeric material and forming an active mass (7m1, 7m2, 7m3). A member (8) of a second material denser than the elastomeric material is also located within the elastomeric material, adjacent to the active mass (7m1, 7m2, 7m3), for coupling to the rail (1) so as to provide a resonant surface against which the active mass (7m1, 7m2, 7m3) can vibrate. Alternatively, or in addition, a tuned absorber (5A, 5B) has a first active mass (7m1) and at least one further active mass (7m2, 7m3) arranged so as to be effectively coupled for vibration in a first frequency range and such that the or each further active mass (7m2, 7m3) is decoupled from the first active mass (7m1) for vibration in a second frequency range higher than the first.