调光式荧光灯电子镇流器研究

提出了一种由Buck-Boost功率因数校正电路和Class-D谐振逆变器组成的单级调光式荧光灯电子镇流器的实现和控制新方案,并由40W荧光灯的实验样机得出分析结论和设计方法。结果表明,这种镇流器结构简单,直流母线电压低于300V,适合于220V/50Hz电网工作,功率因数达到0.98,THD低于13%,并且能够实现平滑调光。

红外动态图象转换器

本文描述了一种新颖的空间光调器——液晶光阀(LCLV),介绍了它的结构、工作原理和性能。及其在军事和商业领域中的应用.它是实现红外成象制导仿真、可见光/红外动态图象转换、光信息处理和光计机的关键设备.液晶光阀以其性能和结构上许多优点,而成为实际应用最多最有前途的器件之一.

Widely-wavelength-tunable brillouin fiber laser with improved optical signal-to-noise ratio based on parity-time symmetric and saturable absorption effect

A widely-wavelength-tunable Brillouin fiber laser(BFL)with improved optical signal-to-noise ratio(OSNR)based on parity-time(PT)symmetric and saturable absorption(SA)effect is present.This novel BFL realizes PT symmetry and SA effect through polarization-maintaining erbium-doped fiber(PM-EDF)Sagnac loop,which is composed of a PM-EDF,a coupler and two polarization controllers(PCs).By using the inherent birefringence characteristic of PM-EDF,two feedback loops in orthogonal polarization state are formed when the Strokes signal in injected.One of these loops provides gain in the clockwise direction with in the Sagnac loop,while the other loop generates loss in the counterclockwise direction.By adjusting the PCs to control the polarization state of the PM-EDF,a single-longitudinal-mode(SLM)BFL can be achieved,as the PT symmetry is broken when the SA participating stimulated Brillouin scattering(SBS)gain and loss are well-matched and the gain surpasses the coupling coefficient.Compared to previous BFLs,the proposed BFL has a more streamlined structure and a wider wavelength tunable range,at the same time,it is not being limited by the bandwidth of the erbium-doped fiber amplifier while still maintaining narrow linewidth SLM output.Additionally,thanks to SA effect of the PM-EDF,the PT symmetric SBS gain contract is enhanced,resulting in a higher optical signal-to-noise(OSNR).The experimental results show that the laser has a wide tunable range of 1526.088 nm to 1565.498 nm,an improved OSNR of 77 dB,and a fine linewidth as small as 140.5 Hz.

10Gb/s EML Module Based on Identical Epitaxial Layer Scheme

A 10Gb/s transmitter module containing an electroabsorption modulator monolithically integrated with a distributed feedback (DFB) semiconductor laser is fabricated using the identical epitaxial layer scheme.Gain-coupling mechanism is employed to improve the single mode yield of the DFB laser,while inductively coupled plasma dry etching technique is utilized to reduce the modulator capacitance.The integrated device exhibits a threshold current as low as 12mA and an extinction ratio over 15dB at -2V bias.The small signal modulation bandwidth is measured to be over 10GHz.The transmission experiment at 10Gb/s indicates a power penalty less than 1dB at a bit-error-rate of 10 -12 after transmission through 35km single mode fiber.

Ridge Waveguide Electro-Optic Polymer Modulator with a New Kind of Corona Poled Crosslinkable Polyurethane

A polymer electro optic modulator has been fabricated with the functional layer acting as a kind of corona poled crosslinkable polyurethane. The three optical layers, namely waveguide, photolithography and oxygen are fabricated by spin coating. With the Reactive Ion Etching method, the ridge of the waveguide is constructed. With light at 1 31μm being fiber coupled to waveguide, the mode and the modulation properties of these devices are demonstrated in a micron control system.

A High-Performance Silicon Electro-Optic Phase Modulator with a Triple MOS Capacitor

We propose and analyze a novel Si-based electro-optic modulator with an improved metal-oxide-semiconductor （MOS） capacitor configuration integrated into silicon-on-insulator （SOl）. Three gate-oxide layers embedded in the silicon waveguide constitute a triple MOS capacitor structure, which boosts the modulation efficiency compared with a single MOS capacitor. The simulation results demonstrate that the Vπ Lπ product is 2. 4V · cm. The rise time and fall time of the proposed device are calculated to be 80 and 40ps from the transient response curve, respectively,indicating a bandwidth of 8GHz. The phase shift efficiency and bandwidth can be enhanced by rib width scaling.

A GaAs-Based MOEMS Tunable RCE Photodetector with Single Cantilever Beam

A GaAs-based micro-opto-electro-mechanical-systems(MOEMS) tunable resonant cavity enhanced(RCE) photodetector with a continuous tuning range of 31nm under a 6V tuning voltage is demonstrated.The single cantilever beam structure is adopted for this MOEMS tunable RCE photodetector.The maximum and minimum peak quantum efficiency during the tuning are 36.9% and 30.8%,respectively.The maximum and minimum full-width-at-half-maximum (FWHM) are 20nm and 14nm,respectively.The dark current density is 7.46A/m2 without bias.

A Wavelength Tunable DBR Laser Integrated with an Electro-Absorption Modulator by a Combined Method of SAG and QWI

We report a wavelength tunable electro-absorption modulated DBR laser based on a combined method of SAG and QWI. The threshold current is 37mA and the output power at 100mA gain current is 3.5mW. When coupled to a single-mode fiber with a coupling efficiency of 15% ,more than a 20dB extinction ratio is observed over the change of EAM bias from 0 to -2V. The 4.4nm continuous wavelength tuning range covers 6 channels on a 100GHz grid for WDM telecommunications.

Monolithically Integrated Laser Diode and Electroabsorption Modulator with Dual-Waveguide Spot-Size Converter Output

A 1.60μm laser diode and electroabsorption modulator monolithically integrated with a novel dual-waveguide spot-size converter output for low-loss coupling to a cleaved single-mode optical fiber are demonstrated.The devices emit in a single transverse and quasi single longitudinal mode with an SMSR of 25.6dB.These devices exhibit a 3dB modulation bandwidth of 15.0GHz,and modulator DC extinction ratios of 16.2dB.The output beam divergence angles of the spot-size converter in the horizontal and vertical directions are as small as 7.3°×18.0°,respectively,resulting in a 3.0dB coupling loss with a cleaved single-mode optical fiber.

Butt-Joint Monolithically Integrated DFB-LD/EA-MD Light Source for 10Gbit/s Transmission

This paper reports on the design,fabrication,and performance of an integrated electro-absorptive modulated laser based on butt-joint configuration for 10Gbit/s application.This paper mainly aims at two aspects.One is to improve the optical coupling between the laser and modulator;another is to increase the bandwidth of such devices by reducing the capacitance parameter of the modulator.The integrated devices exhibit high static and dynamic characteristics. Typical threshold current is 15mA,with some value as low as 8mA.Output power at 100mA is more than 10mW.The extinction characteristics,modulation bandwidth,and electrical return loss are measured.3dB bandwidth more than 10GHz is monitored.

Monolithic Integration of a Widely Tunable Laser with SOA Using Quantum-Well Intermixing

This paper presents an SG-DBR with a monolithically integrated SOA fabricated using quantum-well intermixing （QWI） for the first time in China's Mainland. The wavelength tuning range covers 33nm and the output power reaches 10mW with an SOA current of 50mA. The device can work at available channels with SMSR over 35dB.

1.55μm Fabry-Perot Thermo-Optical Tunable Filter with Amorphous-Si as Cavity

A 1.55μm Fabry-Perot (F-P) thermo-optical t unable filter is fabricated.The cavity is made of amorphous silicon (a-Si) layer grown by electron-beam evaporation technique.Due to the excellent thermo-optical property of a-Si,the refractive index of the F-P cavity will be changed by heating;the transmittance resonant peak will therefore shift substantially.The measured tuning rang is 12nm, FWHM (full-width-at-half-maximum) of the transmissi on peak is 9nm,and heating efficiency is 0.1K/mW.The large FWHM is mainly due to th e non-ideal coating deposition and mirror undulation.Possible improvements to increase the efficiency of heating are suggested.

Mach-Zehnder Electro-Optic Polymer Modulator with C orona Poled Core Layer

A Mach-Zehnder(MZ) electro-optic(EO) modulator are real iz ed,with three optical layers as polymer materials.The functional layer is the co rona poled crosslinkable polyurethane.The ridge waveguide is fabricated by using the spin-coating,poling,photolithography and oxygen reactive ion etching(RIE) techniques.The mode and the modulation properties of these devices are demonstra ted in a micron control system,while the light source works at the wavelength of 1 31 or 1 55 micron.

Experimental comparison between corona and contact poling for EO polymer modulators

Two different poling techniques-corona poling and contact poling in the backdrop of electro-optic （EO） polymer modulators are compared. A 3-layer structure EO polymer modulator is prepared for the poling. The poling setups and procedures of these two different methods are given. It is found that a well-controlled precure step is very critical, otherwise it will result in either lower poling efficiency or damaged film. Experimental results show that contact poling does not create severe surface damage as corona poling and poling voltage is much lower, but corona poling provides higher EO effect than contact poling. Besides, contact poling can provide poling size as large as the substrate size.

Widely Tunable Sampled-Grating DBR Laser

The 3-section SG-DBR tunable laser is fabricate d using an ion implantation quantum-well intermixing process.The over 30nm discontinuous tuning range is achieved with the SMRS greater than 30dB.

An Electroabsorption Modulator Monolithically Integrated with a Semiconductor Optical Amplifier and a Dual-Waveguide Spot-Size Converter

A semiconductor optical amplifier and electroabsorption modulator monolithically integrated with a spotsize converter input and output is fabricated by means of selective area growth,quantum well intermixing,and asymmetric twin waveguide technology. A 1550-1600nm lossless operation with a high DC extinction ratio of 25dB and more than 10GHz 3dB bandwidth are successfully achieved. The output beam divergence angles of the device in the horizontal and vertical directions are as small as 7.3°× 18.0°, respectively, resulting in a 3.0dB coupling loss with a cleaved single-mode optical fiber.

An Integratable Distributed Bragg Reflector Laser by Low-Energy Ion Implantation Induced Quantum Well Intermixing

An integratable distributed Bragg reflector laser is fabricated by low energy ion implantation induced quantum well intermixing.A 4 6nm quasi continuous wavelength tuning range is achieved by controlling phase current and grating current simultaneously,and side mode suppression ratio maintains over 30dB throughout the tuning range except a few mode jump points.

Tunable Distributed Bragg Reflector Laser Fabricated by Bundle Integrated Guide

The tunable BIG RW distributed Bragg reflector lasers with two different coupling coefficient gratings are proposed and fabricated.The threshold current of the laser is 38mA and the output power is more than 8mW.The tunable range of the laser is 3 2nm and the side mode suppression ratio is more than 30dB.The variation of the output power within the tunable wavelength range is less than 0 3dB.

An Open-Loop Test of a Resonator Fiber Optic Gyro

The resonator fiber optic gyro （R-FOG） ,which utilizes a resonance frequency change due to the Sagnac effect,is a promising candidate for the next generation inertial rotation sensor. In this study, an open-loop R-FOG is set up using phase modulation spectroscopy. First,the demodulation curve is obtained using a lock-in amplifier. From the demodulation signal,a gyro dynamic range of ± 4.2rad/s is obtained. Then,using different phase modulation frequencies,the open-loop gyro output signal is measured when the gyro is rotated clockwise or counterclockwise. The bias drift as a function of time is also measured. The fluctuation of the output over 5s is about 0.02rad/s. The drift can be reduced by taking countermeasures against system noise.

A Novel Optical Gate by Integration of a Photodiodeand an Electroabsorption Modulator

A compact and stable three-port optical gate has been successfully fabricated by monolithically integrating a simple photodiode and an electroabsorption modulator. The gate shows an excellent DC logic ＂and＂ function with different load resistors. Its dynamical characteristics without packaging have also been measured. We observed a dynamic extinction ratio of over 7dB with a 95012 load resistor and a 7mW control light power at 622Mbit/s.