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Lv H.,Huazhong University of Science and Technology | Yu Y.,Huazhong University of Science and Technology | Shu T.,Huazhong University of Science and Technology | Huang D.,Huazhong University of Science and Technology | And 2 more authors.
Optics Express | Year: 2010

Photonic ultra-wideband (UWB) pulses are generated by direct current modulation of a semiconductor optical amplifier (SOA) section of an SOA-integrated sampled grating distributed Bragg reflector (SGDBR) laser. Modulation responses of the SOA section of the laser are first simulated with a microwave equivalent circuit model. Simulated results show a resonance behavior indicating the possibility to generate UWB signals with complex shapes in the time domain. The UWB pulse generation is then experimentally demonstrated for different selected wavelength channels with an SOA-integrated SGDBR laser. ©2010 Optical Society of America.

Accelink Technologies Co | Date: 2012-09-27

A hybrid fiber amplifier and method of adjusting gain and gain slope of thereof. The hybrid fiber amplifier comprises: RFA and EDFA that does not comprise variable optical attenuator. The RFA comprises pump signal combiner, pump laser group, out-of-band narrow-band filter, and photodetector. The EDFA comprises input coupler, erbium-doped fiber, output coupler, input photodetector, and output photodetector that are connected in sequence. The hybrid fiber amplifier also comprises control module that coordinates and controls EDFA and/or RFA to adjust gain and/or the gain slope based on desired amplification requirements. The EDFA and/or RFA can be coordinated and controlled by using the control module to achieve desired amplification effect. In addition, the EDFA does not comprise the variable optical attenuator, which avoids problems caused by the variable optical attenuator. The hybrid fiber amplifier and method of adjusting gain and gain slope thereof are applicable to technical field of optical communications.

Accelink Technologies Co | Date: 2013-03-28

This invention involves and discloses a heat control device for power equipment, which comprises heat source, heat sink base plate, heat insulation layer, dissipation heat sink and thermal control switch, wherein the heat source is placed on and in contact with dissipation heat sink, and its bottom is in direct lap joint with heat sink base plate, wherein the heat insulation layer is set around heat sink base plate, wherein the thermal control switch is placed on heat sink base plate. This invention of heat control device is one that demonstrates excellent low temperature thermal insulation property for key components or heat-sensitive elements of power equipment. The heat control device applying technical solutions described in this invention features easy manufacturing, low cost and reliable performance.

A single-pump multi-wavelength lasing semiconductor Raman pump laser comprises a thermoelectric cooler arranged in a shell; a heat transition bearing platform arranged in the thermoelectric cooler; a semiconductor Raman pump laser tube core arranged on the heat transition bearing platform; and a coupling lens group , a thermistor and a backlight detector that are arranged on the heat transition bearing platform respectively. The pump laser tube core, the backlight detector, the thermistor and the thermoelectric cooler are electrically connected to pins outside a laser tube shell. A pump combination apparatus comprises a first signal transmission fiber, a pump signal combiner and a second signal transmission fiber that are sequentially connected to each other. An input terminal of the pump signal combiner is connected to an output terminal of an isolated polarization beam combiner and depolarizer. Two polarization maintaining fiber input terminals of the isolated polarization beam combiner and depolarizer are correspondingly connected to one single pump multi-wavelength lasing semiconductor Raman pump laser respectively.

Accelink Technologies Co | Date: 2012-10-29

An external-cavity tunable laser with a flexible wavelength grid tuning function comprises a resonant cavity, collimating lenses, an optical isolator, and an output optical fiber. The resonant cavity comprises a semiconductor gain chip, a beam expander collimating lens, a combined liquid crystal tunable filter assembly, and a reflecting mirror. A current injected to the semiconductor gain chip is converted to broadband spontaneously radiating photons through electrical-to-optical conversion, and the photons are spread along a waveguide toward two sides. A part of photons with special frequencies go back and forth multiple times in the resonant cavity to form a laser after a threshold condition is met. The laser is collimated by the collimating lens, passes through the optical isolator, is coupled by the collimating lens, and enters the output optical fiber.

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