Novel Grating Design for Out-of-Plane Coupling With Nonuniform Duty Cycle

We propose a waveguide grating coupler with nonuniform duty cycle for the out-of-plane coupling of light from a planar waveguide to an optical fiber, and evaluate the optical performances based on Bloch-wave analysis. The mode profile and focusing performance of the diffracted output beam are investigated in terms of the duty cycle to improve optical coupling efficiency.     

Design and performance of FSK-direct detection scheme for opticalFDM systems

The authors describe the design and performance of an optical frequency-division-multiplexing (FDM) system that uses a frequency-shift-keying (FSK) direct detection scheme. This system utilizes a Mach-Zehnder type periodic filter as a channel selective filter and optical frequency discriminator. Requirement conditions for laser diode linewidth, frequency deviation, channel frequency spacing, detuning of optical filters, and signal power variance are discussed. These characteristics are experimentally confirmed using planar waveguide type filters     

基于微环延时的宽带相控阵天线系统

微环作为一种典型的平面光波导回路,具有结构紧凑、性能可靠等特点,而用其制成的波导延时芯片集成度高、体积小,与其他光延时器件相比,更适合于贴近阵面安装。因此提出了一种基于阵元级微环延时、子阵级光纤延时的宽带相控阵天线系统,并在均匀线阵的情况下,对所提天线系统进行了数学建模和性能仿真。由仿真结果可知,与一般的阵元级移相、子阵级光纤延时的相控阵系统相比,所提系统能够更有效地满足电子对抗宽带宽角扫描的需求。     

Theoretical analysis of integrated collimating waveguide lens

An integrated collimating waveguide lens is analyzed for applications which require the focusing of an optical beam onto the waveguide of a planar lightwave circuit. The lens has a refractive index profile which is parabolically graded as a function of height to focus light in the vertical plane, and has a convex front face to focus light in the horizontal plane. Analysis based on the propagation of a Gaussian field is used to design a lens pair which minimizes the optical loss for a given propagation length. The beam propagation method is used to identify fabrication tolerances which may have impact on the performance of the lens pair. The lens pair has application in micro-optoelectromechanical (MOEM) switches based on planar optical waveguide circuits.     

Waveguide grating-based spectrometric transducers

A spectrometric transducer is a basic element of an optical measurement microsystem. This article explains the principle of operation of waveguide grating-based spectrometric transducers developed for telecommunication applications, their technological limits, and performance. These issues include optical loss (both total loss and the uniformity of loss as a function of channel number), crosstalk (both from adjacent or nearby channels and from those far away, called "background" in this article), polarization sensitivity (inherent in planar waveguide devices), and wavelength accuracy. The article also looks at commercialization issues such as long-term reliability, packaging, and cost. Even though the focus of this article is InP-based etched echelle grating demultiplexers, all of the lessons learned are independent both of the material system and the nature of the planar demultiplexer whether phasar or echelle grating.     

从OFC 2003看平面光波导器件的发展动向

概述了2003年OFC会议上报道的平面光波导器件，着重介绍了平面光波导器件在新材料、新工艺、新结构方面的新进展和发展方向。     

Optical frequency-selective filters in ion-exchanged waveguides

A narrow-band reflection (stop-band) optical filter has been constructed in a planar optical waveguide made by ion exchange of silver in soda-lime glass. A comparison of the measured and computed performance of this optical filter is given. The filter has a bandwidth of 0.35 nm at a centre wavelength of 611 nm.     

利用时域有限差分法进行光波导器件的仿真

将理想匹配层（PML）吸收边界条件用于平面光波导结构的时域有限差分法（FDTD）分析，并对微腔体谐振环进行了数值计算模拟。证明了采用PML吸收边界条件的FDTD法应用于平面光波导结构分析的有效性。本方法对平面光波导的计算机辅助设计（CAD）具有实际意义，可用于分析任意复杂结构的平面光波导。     

Waveguide properties of optical thin films grown by pulsed laser deposition

The propagation of optical beams in optical thin films grown by pulsed laser deposition is studied numerically in order to predict the influence of the film curvature on the performance of planar waveguide lasers. Several waveguiding structures are considered. The confinement of both the pump and the signal fields as well the overlap between the beams during propagation are examined.     

Monolithically integrated optical channel monitor for DWDM transmission systems

The design, fabrication, and performance of an InP-based monolithically integrated optical power monitor are presented. It contains 44 wavelength channels separated by 100 GHz and demonstrates record small footprint size. The device's major components, which include the echelle diffractive grating demultiplexer, passive waveguide circuitry and single-mode vertically integrated waveguide PIN photodetectors, are characterized and discussed as generic building blocks of InP-based planar lightwave technology for DWDM.     

Effects of the Planar Optical Waveguide Thicknes on the Transmision Attenuation

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Study of optical bistability and multistability with optical waveguide modulator

Using a planar optical waveguide electro-optic modulator and simple double beam interfering device, the experimental study of optical bistability and multistability is successfully performed. The waveguide modulator is made by depositing aluminium as electrodes on the Ti-diffused LiNbO₂ planar optical waveguide which is fabricated by ourselves. Laser beam is coupled directly into the end of optical waveguide modulator and out of the Bi₁₂GeO₂₀ prism. Optical rotation arising from Bi₁₂GeO₂₀ crystal is overcome in experiment. In addition to analyzing and discussing optical bistability, the multistabilitical hysteresis curves of different shapes obtained in experiments are particularly investigated.     

Effects of the Planar Optical Waveguide Thickness on the Transmission Attenuation^①

By analyzing and computing,according to the wave theory of planar optical waveguide attenuation,a new opinion is put forward.A series of transmission atteenuation with waveguide film-thickness are given and it illustrates that optical transmission is not carrying out efficiently within some waveguide film-thickness.     

采用光波导调制器进行的光学双稳态和多稳态的研究

采用平面光波导电光调制器及简单的双光束干涉装置成功地进行了光学双稳态和多稳态的实验研究。光波导调制器是在自制的钛扩散铌酸埋平面光波导上蒸镀铝电极制成的。采取激光由调制器端面直接输入,由锗酸铋棱镜耦合输出的方式。实验中消除了锗酸铋晶体旋光性的影响。本文除了对光学双稳性进行了分析讨论外,还着重对不同形态的多稳实验回线进行了探讨。     

平面波导有效折射率数值解及光场分析

提出了一种计算有效折射率（ｎｅｆ）的数值迭代算法,并通过计算得出平面光波导的光场分布,并由此确定平面光波导的厚度。     

Planar 1 × N optical multiplexer with nearly ideal response

It is shown that nearly ideal multiplexing and demultiplexing can be realized in optical networks by using a planar arrangement of two waveguide gratings combined with a reflector (or a waveguide lens). The new arrangement, realized by using a new type of waveguide array, implies higher spectral efficiency and higher capacity for future optical networks     

基于后焦面成像的聚合物平面波导光学参数测量仪

基于后焦面成像确定波导传播特性的基本原理,结合平面波导中的菲涅尔反射理论,设计了一种聚合物平面波导光学参数测量仪.通过MATLAB拟合处理数据实现了对样品局部折射率和厚度高精度、高空间分辨率的实时测量,平面波导厚度测量精度可以达到纳米量级,空间分辨率可达到300 nm.该测量仪结构简单、易于操作,在光学传感和细胞内生物传感领域具有很高的应用价值.     

Birefringent properties of GaAlAs multiple quantum well planaroptical waveguides

Planar GaAlAs optical waveguides in which the waveguide core region is composed of multiple quantum wells are considered. Calculations of optical waveguide dispersion are performed to determine variations in effective refractive indexes for TE and TM modes and in the mode birefringence for large ranges of total waveguide thickness, number, and refractive index of well and barrier layers, and the ratio of well and barrier layer thickness. Ranges of these parameters which yield optical waveguides having unusually high birefringence and optical waveguides supporting single polarization planar propagation only are identified     

基于平板型导光板的太阳能聚光系统

针对传统线性聚光系统聚光光斑辐照度不均匀的问题,提出了一种由曲面线聚焦菲涅耳聚光器阵列及平板型导光板所组成的、系统高度小于40mm的小体积聚光系统方案,建立了曲面线聚焦菲涅耳透镜的一般方程,给出导光板V形槽设计公式,并采用正交试验法和光学仿真实验对聚光器系统的各项结构参数进行优化设计,同时分析了曲面线聚焦菲涅耳的加工误差及导光板安装偏角误差的影响。结果表明:优化后系统在采光面积500mm×200mm、聚光比50倍时,聚光效率可达75%,聚焦光斑均匀性优于88%,且入射太阳光偏角在±7°内聚光效率大于50%。通过拼接可获得不同聚光倍数系统,由仿真实验得出在160倍聚光比内,效率高于50%,均匀性优于85%。     

硅基片上集成二维光控多波束形成的研究

传统雷达系统在当今日益复杂的电磁环境中面临严重挑战,而集成微波光子学技术可突破传统雷达的技术瓶颈,具有大带宽、高分辨率、高复用度、高集成化等技术优势。本文基于集成微波光子技术,研制了一款硅基集成二维光控多波束形成系统样机,提出了一种基于二氧化硅平面光波导的片上集成二维光控多波束形成系统架构,结合流片加工平台完成了关键光芯片的设计流片和封装测试,最终完成系统样机整机联调测试,并对实验结果进行理论计算处理,验证了硅基集成波束形成系统的关键性能指标。系统具有大瞬时带宽、二维同时多波束、各波束多波位独立扫描的能力,与此同时兼具硅基光子集成技术的小型化、轻量化、低成本等优势,试验结果验证了集成微波光子技术应用于雷达系统的先进性和应用潜力。