新型对称分束偏光棱镜

采用方解石——玻璃二元结构,提出了一类新型对称分束偏光棱镜;给出了棱镜结构及特性参数的理论分析和实验结果。结果表明,该类棱镜既具对称分束特点,又具良好的偏光性能。     

微角分束偏光棱镜分束角的特性研究

为了了解微角分束偏光棱镜的分束特性,根据冰洲石晶体的光学性质以及光在棱镜入射与出射介面和棱镜中的传播方向,在光正入射的条件下,分析了棱镜的分束角随工作波长的变化关系; 在工作波长一定的条件下,分析了入射角对棱镜分束角大小的影响及规律; 设计了实验,对制作的棱镜样品进行了实验测试。结果表明,微角分束偏光棱镜的分束角随工作波长而变,且波长越短,分束角越大; 在棱镜的主截面内,入射角由-20°~20°变化时,分束角呈非线性由小变大。这一结果对于微角分束偏光棱镜的设计和使用具有实际价值。     

一种新型的90o分束偏光棱镜

为了节省稀有昂贵的冰洲石晶体材料,且在保证偏光棱镜高透射比和消光比的情况下实现光路的90o分束,采用在两块ZBaF3玻璃中间胶合冰洲石晶体薄片的三元结构方案,设计了一种新型的90o分束偏光棱镜。实验测试表明：该分束偏光棱镜的透射比近90%,消光比优于10-3,而且很好的实现了光路的90o分束,在一定情况下能够取代冰洲石晶体式的设计。     

一种新型的90°分束偏光棱镜

为了节省冰洲石晶体材料,并且在保证偏光棱镜高透射比和消光比的情况下实现光路的90°分束,采用在两块ZBaF₃玻璃中间胶合冰洲石晶体薄片的三元结构方案,设计了一种新型的90°分束偏光棱镜。实验测试表明,该分束偏光棱镜的透射比近90%,消光比优于10^－3,而且实现了光路的90°分束。可在一定情况下实现取代冰洲石晶体式设计的目的。     

一种冰洲石-氟化钡紫外直角分束棱镜设计

为了节省冰洲石晶体材料、并实现偏光棱镜光路的直角分束，采用冰洲石晶体与氟化钡晶体二元复合的方案，设计了一种冰洲石-氟化钡紫外直角分束偏光镜。以波长为265.6nm的紫外光为例给出了设计实例。从理论上分析了入射光经过该偏光棱镜后，e光、o光的分束角和光强分束比随入射角及入射光波长的关系，并通过计算软件作出关系曲线图。结果表明，该偏光棱镜分束角与直角偏差小，e光、o光的光强分束比约为1:1；在240nm~400nm的波段范围内，垂直入射对应的直角分束偏差小于1.0°，光强分束比与1的偏差在0.02以内，具有较宽的光谱适用范围。该研究对直角分束棱镜的设计、制作以及实际使用提供了有价值的参考。     

单元大分束角双反射偏光分束镜

双反射偏光分束镜是利用晶体的双反射原理设计而成。就单元结构的该类棱镜而言,不仅在偏光分束镜的主要技术指标——消光比、总透射比、抗光损伤阈值等优于双折射型偏光分束镜,且可同时实现光束转向,这一特点是对偏光分束棱镜应用范围的重要开拓。该类冰     

双反射可调剪切差平行分束偏光器研制

详细分析了由两只双反射偏光分束镜组成的平行分束偏光系统的平行分束原理,以及所必备的条件。当组成系的两只直角双反射偏光分束镜的结构角相同且平行放置时,所组成的系统可将输入的非偏振光分成两偏振面相互平行的线偏振光,并平行地从系统中输出。当调节一只棱镜与另一只棱镜的相对位置时,剪切差可连续变化。     

Wollaston式对称分束偏光棱镜

基于Wollaston棱镜的结构,给出了对称分束偏光棱镜的一种新的设计,即通过修正光束的出射端而来实现对称分束.给出了出射端面的修正角与棱镜的结构角之间的关系式.以632.8nm波长为例分析了出射端面的修正角与棱镜的结构角之间的关系曲线,并且分析了此修正角与波长的关系曲线.     

双洛匈棱镜的设计及性能分析

设计了一种新型偏光分束棱镜：双洛匈棱镜。给出了双洛匈棱镜分束角的精确表达式,并从理论上分析了分束角随棱镜结构角和入射光光波波长的变化关系,以及棱镜的光强分束比。结果表明：对于确定的单色光,分束角随结构角的增大而增大;对于确定的结构角,分束角则随入射光波长的增加而减小：棱镜的光强分束比近似为1。与常规洛匈棱镜的分束角比较...     

钒酸钇偏光分束棱镜光强分束比的入射角效应

为了分析He-Ne激光斜入射钒酸钇偏光分束棱镜时光强分束比随入射角度的变化关系,根据几何关系、菲涅耳公式及相位匹配条件从理论上推导出光强分束比的数学表达式,通过实验验证,发现理论值和实验值相符合,并对存在的误差进行了分析。这为钒酸钇棱镜在偏光器件中的应用提供了重要的参考价值。     

Art output mirror for fir laser

ATR prism was used firstly as the FIR laser output coupler. Such output mirror possesses good separation of the pump (λ≈10µm) and FIR radiation without losses. Transmittance of this mirror can be simply controlled by adjustment of gap between two output prisms. The dependence of mirror output characteristics on pump radiation polarization, prism refractive index, gap between prisms are under consideration.     

Design and realization of phase retardation-control polarization controllers based on artificial birefringence

Polarization controllers(PCs) are indispensable passive components for state of polarization(SOP) control in optical fiber communication systems.In order to overcome the disadvantages of existing polarization controller(PC),a novel PC based on the artificial birefringence is designed in this paper.The PC results from the concatenation of 3 phase retardation control units each of which consists of two polarization beam splitters,two prisms and one piezoz-lectric transducer(PZT) piezoelectric ceramic.The experimental results show that the proposed PC can convert an arbitrary input SOP to any expected output one with high accuracy under low control voltage.     

棱镜全息干涉法制作二维光子晶体的研究

模拟了Top-cut棱镜全息干涉生成的各种光学晶格结构,为棱镜法制作光子晶体提供参考。用全息干涉理论分析了top-cut六棱镜多光束干涉生成的光学晶格结构,考虑了光束数目、偏振方向以及位相的不同对晶格结构的影响。改变光束数目可以生成不同周期的正六角、斜六角光学晶格;改变光束偏振特性则影响光学晶格格点的形状;改变光束初位相可以生成蜂窝状结构等。另外还模拟了top-cut五棱镜所生成的十重旋转对称光学准晶结构。并且用平面波展开法计算了六角和蜂窝结构的有机光子晶体带隙图,证明了蜂窝结构更容易产生大的光子带隙。     

Reconfigurable wavelength add-drop filtering based on a Banyannetwork topology and ferroelectric liquid crystal fiber-optic switches

This paper presents a modular optical implementation of a Banyan network by using the physical flexibility of the optical fiber to form the interconnections between compact switching stages based on bulk polarization optics. Specifically, these switching stages use total internal reflection (TIR) prisms with ferroelectric liquid crystal (FLC) polarization rotators to form compact modules. Using this Banyan network implementation, a reconfigurable multiwavelength add-drop filter for wavelength division multiplexed (WDM) applications is proposed. Experimental results for our fiber connected 2 in-2 out FLC-based bulk-optic switching stage gives a ~6.7 dB optical insertion loss and a ~-40 dB optical interchannel crosstalk level. A low 2 dB optical insertion loss design number is expected with optimized components, realizing high (e.g., 35 μs) switching speed and low crosstalk switching networks     

高消光比测试系统衰减器的研究

为了提高消光比测试系统的测试精确度,利用偏振干涉原理研究设计了一种用于此系统的衰减器,并对它的工作机理进行了详细分析。此衰减器主要包括3个偏光棱镜,1个λ/4波片(632.8nm),两个步近电机。它可以对光强度进行连续调节,其调节范围在0~60dB之间,插入损耗小于1.5dB,消除了以往更换固定衰减量的衰减器带来的误差。此光衰减器用在高消光比测试系统中可以得到优于10-7量级的消光比,它不仅可以用于高消光比测试系统,同样可用于其它光学测试系统。当用消色差波片代替λ/4波片时,它能对多种波长的光进行衰减,扩大测试系统对光谱区的使用范围。     

High-isolation polarization-independent quasi-optical circulator

A polarization-independent quasi-optical circulator having high isolation over a wide wavelength range is reported. The proposed quasi-circulator is composed of two polarization beam splitters, two pentagonal prisms, two nonreciprocal rotators, and two walkoff polarizing beam splitters. Its structure is very simple. A three-port quasi-circulator has been fabricated with single-mode fibers. Its insertion loss and isolation have been measured to be ⩽1.7 and ⩾48.6 dB, respectively, at the nominal wavelength of 1.3 μm. A loss ratio of over 47.0 dB has been realized. The wavelength range over a 50-dB isolation between two fibers was measured to be about 50 nm     

Direct bandwidth and polarization control of an XeF unstableresonator laser

Several approaches to directly controlling the bandwidth and polarization of an unstable resonator without the use of an injection source are discussed. The techniques are based on the control of oscillations within (and around) the resonator core through the use of small, subaperture optical elements (e.g. etalons, Brewster-angle plates, Glan-air prisms) mounted at select locations within the system. The experiments were performed on a 4-J, e-beam pumped, XeF ( B→X) laser operating at ambient temperature, with output predominantly at 353.2 nm. A spectral linewidth of less than 12 GHz (0.05 Å) and nearly perfect linear polarization were simultaneously achieved at high laser efficiency. Oscillation on a single, dominant transverse mode has been demonstrated. The increased cost and complexity of injection-controlled systems are avoided through the use of these direct, core-control approaches     

成像光谱仪复合色散棱镜支撑设计与试验

复合色散棱镜是高分辨力星载成像光谱仪的关键分光元件,其光机支撑是成像光谱仪工程研制阶段必须解决的重要问题。首先介绍了复合色散棱镜的工作原理,在此基础上给出了复合色散棱镜光机支撑的技术指标要求;接着综合考虑了热匹配、密度、弹性模量、可加工性等因素后选择了棱镜支撑结构材料;然后运用温度补偿法解决了复合色散棱镜中一块棱镜与支撑结构材料线膨胀系数不匹配的问题,采用半运动学安装方法对两块棱镜进行支撑;最后给出了复合色散棱镜组件力学和热学分析结果并进行了相应试验。试验结果表明:复合色散棱镜组件一阶基频达301.5 Hz,在20℃5℃温度范围内组合光程差优于0.021 （=632.8 nm）,能够满足成像光谱仪工程研制需要。     

干涉因素对偏光棱镜消光比测量的影响

为了消除不同角度入射格兰-泰勒棱镜时透射光谱曲线波动干扰产生的影响,提高消光比测量系统的测量精度,以偏光棱镜作为检偏器,采用二次曲线拟合的方法,对透射曲线的极值点实现了精确判定。并采用二次光强测量方法,对棱镜入射端、出射端、胶合层反射及透射情况进行了理论分析,然后用不同角度入射时棱镜透射谱线的变化规律来解释其干扰发生的程度。结果表明,该方法消除了波动干扰影响,提高了测量棱镜消光比的精度。这一结果解决了空气隙型偏光棱镜消光比测量精度问题,同时对偏光棱镜的正确使用提供了参考建议。