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自调光路灯控制器
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作者 吴国贤 《电子世界》 2014年第5期70-70,共1页
设计一种自调光路灯控制器,控制器主要包括单片机控制模块、人机交互界面、零点检测模块、光强度采集模块与脉冲触发模块,设计目的:控制器可根据环境光照强度,自动调节路灯亮度,达到节能目的。
关键词 自调光 零点检测模块 照强度采集模块
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基于MP2481和BH1710的自调光LED驱动器设计 被引量:4
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作者 孙颖 侯艳波 +1 位作者 张利利 林战国 《电子器件》 CAS 北大核心 2013年第1期105-108,共4页
调光功能是未来LED驱动器发展的一个方向,具有调光功能的LED驱动器不仅可以调节灯光效果,还能在一定程度上达到节能目的。应用白光LED驱动器芯片MP2481与光照度传感器芯片BH1710FVC设计出一款具有自调光功能的LED驱动器。该驱动器以AT89... 调光功能是未来LED驱动器发展的一个方向,具有调光功能的LED驱动器不仅可以调节灯光效果,还能在一定程度上达到节能目的。应用白光LED驱动器芯片MP2481与光照度传感器芯片BH1710FVC设计出一款具有自调光功能的LED驱动器。该驱动器以AT89C2051为控制核心,接收光传感器数据处理后控制MP2481实现自调光功能。试验证明,驱动器实现了自调光的功能,取得了一定的节能效果。 展开更多
关键词 LED驱动器 自调光 MP2481 BH1710
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Population Change of OH and H2O in Water Vapor Glow Discharge Measured Using Concentration Modulation Spectroscopy 被引量:1
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作者 Bao Li Li Wang +3 位作者 Bo Fang Wei-xiong Zhao Lun-hua Deng Huai-liang Xu 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第4期411-416,I0001,共7页
A distributed feedback laser with a wavelength of 2.8μm was used to measure the species produced by water vapor glow discharge.Only the absorption spectra of OH radicals and transient H2O molecules were observed usin... A distributed feedback laser with a wavelength of 2.8μm was used to measure the species produced by water vapor glow discharge.Only the absorption spectra of OH radicals and transient H2O molecules were observed using concentration modulation(CM)spectroscopy.The intensities and orientations of the absorption peaks change with the demodulation phase,but the direction of one absorption peak of H2O is always opposite to the other peaks.The different spectral orientations of OH and H2O reflect the increase or the decrease of the number of particles in the energy levels.If more transient species can be detected in the discharge process,the dynamics of excitation,ionization,and decomposition of H2O can be better studied.This study shows that the demodulation phase relationship of CM spectrum can be used to study the population change of molecular energy levels. 展开更多
关键词 Glow discharge OH radical Concentration modulation spectroscopy Population change
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Investigation of all-optical regeneration based on self-phase modulation in microstructured fibers 被引量:3
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作者 WEI Yan-fen XU Yong-zhao Zhang Xia HUANG Yong-qing REN Xiao-min 《Optoelectronics Letters》 EI 2007年第1期18-21,共4页
All-optical regeneration based on self-phase modulation in microstructured fibers is studied. The effects of pulse peak power into the fiber, pulse width and filter parameters on the performance of the regenerator are... All-optical regeneration based on self-phase modulation in microstructured fibers is studied. The effects of pulse peak power into the fiber, pulse width and filter parameters on the performance of the regenerator are investigated. The effects of normal dispersion and anomalous dispersion of the microstructured fiber on optical regeneration are compared. The nu- merical results show that optical regeneration can be achieved by using microstructured fibers with normal dispersion or anomalous dispersion, but the normal dispersion decreases the oscillatory structure in the broadened spectra and obtain a better regenerator transfer function. In order to achieve optical regeneration, the input peak power into the microstructured fiber and the filter parameters need to meet certain requirements. By optimizing those parameters, a better regeneration result can be obtained. 展开更多
关键词 微结构 再生 自相位调制 滤波器参数
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A review on spatial self-phase modulation of two-dimensional materials 被引量:2
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作者 ZHANG Xue-jun YUAN Zhen-hua +4 位作者 YANG Rui-xin HE Yi-lin QIN Ying-lin XIAO Si HE Jun 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第9期2295-2306,共12页
Self-diffraction appears when the strong laser goes through two-dimensional material suspension,and this spatial self-phase modulation(SPPM)phenomenon can be used to measure nonlinear optical parameters and achieve op... Self-diffraction appears when the strong laser goes through two-dimensional material suspension,and this spatial self-phase modulation(SPPM)phenomenon can be used to measure nonlinear optical parameters and achieve optical switch.At present,the mechanism of SPPM is still ambiguous.The debate mainly focuses on whether the phenomenon is caused by the nonlinear refractive index of the two-dimensional material or the thermal effect of the laser.The lack of theory limits the dimension of the phase modulation to the radius of the diffraction ring and the vertical imbalance.Therefore,it is urgent to establish a unified and universal SSPM theoretical system of two-dimensional material. 展开更多
关键词 nonlinear optics spatial self-phase modulation two-dimensional materials
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Performance Comparison of WDM Systems with Different Duty Cycle
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作者 YUJianjun GUANKejian 《Semiconductor Photonics and Technology》 CAS 1998年第3期166-173,共8页
The performances of nonlinear WDM systems with different duty cycle are compared by means of numerical simulation.The numerical results show that the optical pulse with duty cycle of 0.5 is superior to the conventiona... The performances of nonlinear WDM systems with different duty cycle are compared by means of numerical simulation.The numerical results show that the optical pulse with duty cycle of 0.5 is superior to the conventional NRZ modulation scheme.The conclusion is different from that of some references.The reason is that inter symbol interference is not included in some references.In fact,inter symbol interference plays an important role in nonlinear WDM system.Although the larger the duty cycle is ,the stronger the effect of the cross-phase modulation and self-phase modulation on nonlinear WDM is,however,the larger the duty cycle is,the stronger the inter symbol interference is. 展开更多
关键词 Cross-phase Modulation Dispersion Compensation Self-phase Modulation Wavelength Division Multiplexing
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Microwave photonic bandpass filter based on spectrum-slicing and phase modulator 被引量:2
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作者 靳胜才 张爱玲 《Optoelectronics Letters》 EI 2011年第2期113-116,共4页
A tunable microwave photonic bandpass filter with high mainlobe-to-sidelobe ratio (MSR) based on a phase modulator and a dispersive device is proposed. The multi-tap characteristics of the filter are realized by slici... A tunable microwave photonic bandpass filter with high mainlobe-to-sidelobe ratio (MSR) based on a phase modulator and a dispersive device is proposed. The multi-tap characteristics of the filter are realized by slicing a broadband source using a Mach-Zehnder interferometer (MZI) which results in a high MSR of 25 dB. The tunability of the filter is realized by an optical variable delay line (OVDL) in one arm of the MZI, which changes the wavelength spacing of the sliced broadband source and results in a tunable free spectrum range (FSR) of the filter. The central frequency of the bandpass filter is tunable from 10.7 GHz to 27 GHz by changing the wavelength spacing from 0.145 nm to 0.054 nm. 展开更多
关键词 Bandpass filters Modulators Phase modulation
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Location-adaptive transmission for indoor visible light communication 被引量:1
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作者 王春悦 王浪 迟学芬 《Optoelectronics Letters》 EI 2016年第1期69-73,共5页
A location-adaptive transmission scheme for indoor visible light communication(VLC) system is proposed in this paper.In this scheme,the symbol error rate(SER) of less than 10-3 should be guaranteed.And the scheme is r... A location-adaptive transmission scheme for indoor visible light communication(VLC) system is proposed in this paper.In this scheme,the symbol error rate(SER) of less than 10-3 should be guaranteed.And the scheme is realized by the variable multilevel pulse-position modulation(MPPM),where the transmitters adaptively adjust the number of time slots n in the MPPM symbol according to the position of the receiver.The purpose of our scheme is to achieve the best data rate in the indoor different locations.The results show that the location-adaptive transmission scheme based on the variable MPPM is superior in the indoor VLC system. 展开更多
关键词 LIGHT Light transmission LOCATION Pulse position modulation Transmissions
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A widely tunable microwave photonic notch filter with adjustable bandwidth based on multi-wavelength fiber laser
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作者 LI Xin-yang CAO Ye +2 位作者 XU Dong TONG Zheng-rong YANG Jing-peng 《Optoelectronics Letters》 EI 2017年第4期259-262,共4页
A widely tunable microwave photonic notch filter with adjustable bandwidth based on multi-wavelength fiber laser is proposed and demonstrated. The multi-wavelength fiber laser generates the multi-taps of the microwave... A widely tunable microwave photonic notch filter with adjustable bandwidth based on multi-wavelength fiber laser is proposed and demonstrated. The multi-wavelength fiber laser generates the multi-taps of the microwave photonic filter (MPF). In order to obtain notch frequency response, a Fourier-domain optical processor (FD-OP) is introduced to con- trol the amplitude and phase of the optical carrier and phase modulation sidebands. By adjusting the polarization con- troller (PC), different numbers of taps are got, such as 6, 8, 10 and 121 And the wavelength-spacing of the multi-wavelength laser is 0.4 nm. The bandwidth of the notch filter is changed by adjusting the number of taps and the corresponding bandwidths are 4.41 GHz, 3.30 GHz, 2.64 GHz and 2.19 GHz, respectively. With the additional phase shift introduced by FD-OP, the notch position is continuously ttmed in the whole free spectral range (FSR) of 27.94 GHz. The center frequency of the notch filter can be continuously tuned from 13.97 GHz to 41.91 GHz. 展开更多
关键词 Bandpass filters BANDWIDTH Fiber lasers Finite difference method Frequency response Microwave filters
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