3.7～4.8μm中红外带通滤光膜研制

以光学薄膜理论为出发点,系统介绍了3.7～4.8 m带通滤光膜的理论设计与优化、实际生产制备以及成品测试方法。考虑到膜料性能及膜层匹配等问题,分别选用锗和一氧化硅作为高低折射率材料,并以氧化铝作为薄膜基底。确定了滤光膜的基础膜系,并使用Filmaster软件对膜系进行了设计和优化计算。在薄膜蒸镀过程中,根据材料选取合适的镀制工艺。通过温度控制、离子辅助等方法研制出了可靠性与光谱特性皆优的带通滤光膜,并对其光谱特性及膜层质量等进行了测试。根据设计目标修改工艺参数,最终确定可行的工艺流程,从而研制出了符合光学性能设计指标的3.7～4.8 m带通滤光膜。     

中红外3.9 μm长波通截止滤光膜研制

以薄膜光学和激光红外技术为背景,介绍了3.9 μm长波通截止滤光膜的用途、设计与制备方法。基于波动光学原理,首先分析了滤光膜设计方面的难点,其次讨论了薄膜选材、通带展宽、工艺制备等研究过程中的主要技术问题。利用计算机优化软件进行优化计算后,结合离子辅助工艺得到了吸收小、透过率高、光洁度与附着力良好的薄膜。目前相关的技术应用在中红外系统中有效改善了信噪比和响应度。     

氧化铝基体3.7 μm与4.8 μm双波段带通滤光膜研制

以红外光学和薄膜技术为理论背景,详细介绍了氧化铝基体表面3.7 m与4.8 m双波段带通滤光膜的特性、制备及测试方法。氧化铝（Al2O3）由于其透光区域较宽,牢固度好,便于光学系统使用而被经常应用于中波红外光学系统中。采用软件优化计算和双面镀制截止带通滤光膜的方案,通过速率控制、离子辅助等工艺方法研制成功了可靠性和光谱特性皆优的双波段带通滤光薄膜。分析认为设计结构和优化算法对于薄膜通带平坦度、截止深度以及透过率有着明显的影响。制备工艺方面,除了合适的蒸发速率外,采取缓慢蒸发和弱离子能量辅助也是很重要的关键技术,最终光谱透过率测试平均大于87%,通过了环境测试,符合使用要求。     

用于红外焦平面探测器的2.95～5.05 μm带通滤光膜

中波红外焦平面探测器因在红外制导导弹、红外夜视仪等军事领域的重要性而被广泛关注，其中带通滤光膜具有滤除杂散光和保护探测器的作用。本研究的目的是针对中波红外焦平面探测器滤光膜的关键技术问题，通过分析、选材、优化等方法，制备出性能良好的中波红外带通滤光膜。以Ge为高折射率材料和基底，以SiO为低折射率材料，设计了带通膜系结构。不仅实现了在0°入射角下对2.95～5.05 μm波段大于92%的高透过率、通带宽度优于3.7～4.8 μm的常规应用，而且对2.95～5.05 μm之外的其它波段也能达到良好的截止效果。经测试，其光洁度、牢固性等各方面性能良好，可以很好地应用于中波红外焦平面探测器。     

水蒸气分压强对ITO薄膜均匀性和光电性能的影响

直流磁控溅射法低温制备ITO透明导电薄膜的过程中,在衬底温度为60°C其它工艺参数不变的情况下,通过改变通入的水蒸气分压0~6.67×10-3Pa制备了不同结构的薄膜,研究了水蒸气分压对ITO薄膜电阻率和膜厚的均匀性,光电特性,以及晶体结构的影响。水蒸气的引入可以改善ITO薄膜的电阻率均匀性和膜厚均匀性,增加了ITO薄膜的导电性,对ITO膜可见光透过率也有所提高。     

1.3～2.7 μm带通滤光膜研制与分析

光学薄膜技术广泛应用于几乎所有的光学系统、光电系统和光电仪器。新型探测器的发展对1～3 μm近红外波段附近的能量响应提出了滤波的要求。从电磁场理论和麦克斯韦方程出发,介绍了光学薄膜的设计理论,论述了带通滤光膜的设计方法。基于Optilayer软件,以氧化铝为基底,设计了一种工作波段为1.3～2.7 μm的近红外带通滤光膜。考虑到镀膜材料的匹配性问题,选择硫化锌和氟化镱作为高、低折射率材料。采用长波通与短波通相结合的设计方法,并用Optilayer软件完成了膜系的计算和优化。在氧化铝基底双面镀制膜,用电子束蒸发和离子束辅助沉积的制备工艺完成了膜系镀制。用分光光度计对制备样品进行了透过率测试。结果表明,在1.3～2.7 μm设计波段,样品的平均透过率大于95%,符合带通滤光膜的设计要求。     

对向靶溅射AIN薄膜的研究

本文介绍了采用对向靶溅射装置,在较低的基片温度下(<70℃)制备AlN薄膜的方法。通过控制溅射气氛和成膜速率,可以得到符合化学式量比的优质AlN薄膜。将该AlN薄膜作为磁光薄膜的光学匹配膜,使磁光克尔旋转角从0.32°增加到0.72°。     

多角度光谱测量法制备短波通滤光膜技术

详细论述了短波通滤光膜的理论设计与实际制备结果,光谱曲线偏离的原因及修正方法。首先选择高、低折射率膜料设计短波通滤光膜系,然后进行实际膜系制备。由于镀膜机存在控制误差,使得实际膜层制备厚度偏离理论厚度,导致实际制备光谱曲线超差。通过利用多角度光谱测量法对制备结果进行测量,依据多次测量结果的曲线偏离量,判断产生膜层厚度误差的膜料、膜层厚度误差的偏差大小及方向。在修正膜层厚度误差后,制备了光谱曲线平坦变化的短波通滤光膜。这种光谱性能更好的短波通滤光膜可以避免光学系统的偏色效应,此项技术为短波通滤光膜的设计与加工提供了新的理论依据与制备方案。     

光纤通信中帯通滤光膜的研制

光通信以光纤作为信号传输的媒介,由于其传输容量大、速率快、成本低等优点,因此在通信领域得到了广泛应用。随着科学技术的发展,以及5G通信技术的到来,为满足系统的需求,对通信系统中的帯通滤光膜进行研制。此次研究,以SiO2和Ta2O5作为膜层制备材料。然后,使用IBS镀膜设备制备了在13.5度大角度下使用的带通滤光膜,分析并解决了耦合层膜厚监控的问题。制备的帯通滤光膜在861～901 nm处插入损耗小于0.4 dB,透射隔离度大于25 dB,截止带宽小于40 nm,满足该系统使用要求。     

Ge基底8～11.5μm长波通滤光膜的研制

论述了在Ge基底上镀制8～11.5 μm红外长波通滤光膜.通过对Ge基底和Ge、ZnS膜料的色散计算,优化膜系设计,进行工艺实验以及膜层的光学及耐环境实验,制备出满足应用条件的红外长波通滤光片,并已批量生产.     

满足双视场需求的红外模拟光学系统的设计

简述了红外场景产生的技术背景以及基于液晶光阀实现可见光到红外视频图像转换的模拟器的总体结构。重点介绍了一种适用于两种不同视场的红外光电系统测试与评估的动态红外场景模拟器光学系统的设计，其中包括变倍透镜的选择和准直投射光学系统的设计。从理论上分析了利用变倍透镜的变化写入不同放大倍率的可见光图像，来满足视场变化需要的方法；从光学指标的确定，结构、材料的选取到最终光学性能，阐述了准直投射光学系统的设计。此投射光学系统工作在8～ 12 μm , 焦距271.69 mm，视场为±4°，入瞳距150 mm，后工作距离139.2 mm，点列图和传递函数曲线表明此投射光学系统像质达到理想状态。最后分析了光学系统性能参数与指标要求的符合。在满足设计指标的前提下，和变焦系统相比，该光学系统结构简单、成本低、可行性高。     

光子晶体绿光滤波器的研究

利用传输矩阵法设计了一种适用于绿光波段的光子晶体窄带滤波器,并研究了影响滤 波器特性的多种因素。结果表明:适当选取光子晶体结构参数,可将滤波器的中心波长移到绿光波段的532nm处,谱线线宽可达0. 0131nm。此外,随着光子晶体周期层数的增加,线宽进一步变窄;当缺陷层厚度减小时,滤波器的中心波长向短波段移动而谱线宽度几乎保持不变;当入射角增大时,滤波器的谱线宽度变窄但变化幅度不大且在小角度范围( 0～3°)内宽度几乎保持不变。这种绿光窄带滤光器有望在蓝绿光通信中得到应用。     

Porous Nanostructured Optical Filters Rendered Insensitive to Humidity by Vapor‐Phase Functionalization

Water adsorption in many porous optical coatings can cause a detrimental red‐shift in the optical properties. In this study, a porous nanostructured rugate filter is fabricated using the glancing‐angle deposition (GLAD) technique, and rendered insensitive to large changes in ambient humidity by post‐deposition vapor‐phase functionalization. A central defect mode is added to the stop band of the filter by integrating a phase shift into the sinusoidal refractive‐index profile of the film. By monitoring the wavelength of the defect mode under variable humidity conditions, a six‐times reduction in sensitivity to water vapor is observed upon functionalization with 3,3,3‐trifluoropropyltrichlorosilane. Electrical characterization and advancing aqueous contact‐angle measurements are used to verify the hydrophobic properties of the functionalized thin films.     

Optical technique for broadbanding phased arrays

An optical method for broadbanding a phased array is considered. A narrow band feed-through aperture lens comprised of pick-up elements, radiating elements, and360degtype phase shifters is fed by a small feed array with an intervening passive lens. The lens has fixed frequency-sensitive properties. The feed array has variable time delay compensators which are selected in accordance with the desired scan angle in the far field. Using geometrical optics, design formulas are derived that relate bandwidth and scan angle to the minimum number of variable time delayers. To demonstrate performance, diffraction theory is used to calculate patterns, sidelobe levels, and efficiencies as a function of bandwidth and scan angle out to50degscan for several aperture sizes. In the worst cases, the optical system provides somewhat less gain than the comparable constrained subarray antenna; however, it always provides much better sidelobe levels.     

A non-polarization short-wave-pass thin film edge filter

Multilayer dielectric thin film edge filter has serious polarization sensitivity under oblique incidence. The cutoff-bands of the s-polarization and p-polarization light in conventional edge filter will separate obviously under 45° oblique inci- dence, which limits its application. Based on the two chosen materials TiO2 and SiO2, a novel stack structure is pro- posed to design the non-polarization short-wave-pass thin film edge filter. By using the （4H 4L 4H） as the matching layers, the polarization separation at 3 dB transmittance for the thin film edge filter cutoff-band is less than 1 nm at the incident angle of 45°. In this way, the non-polarization short-wave-pass edge filter is easily designed and fabricated.     

Optical and electrical properties of crystalline indium tin oxide thin film deposited by vacuum evaporation technique

Indium tin oxide (ITO) thin film was deposited on glass substrate by means of vacuum evaporation technique and annealed at 200 °C, 300 °C and 400 °C in air for 1 h. The characterization and properties of the deposited film samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-VIS-NIR spectroscopy techniques. From the XRD patterns, it was found that the deposited thin film was of crystalline at an annealing temperature of 400 °C. The crystalline phase was indexed as cubic structure with lattice constant and crystallite size of 0.511 nm and 40 nm, respectively. The SEM images showed that the films exhibited uniform surface morphology with well-defined spherical grains. The optical transmittance of ITO thin film annealed at 400 °C was improved from 44% to 84% in the wavelength range from 250 nm to 2 100 nm and an optical band gap was measured as 3.86 eV. Hall effect measurement was used to measure the resistivity and conductivity of the prepared film.     

晶体二向色性对波片性能的影响

为了更好地在晶体具有二向色性的波段使用波片,采用矩阵光学的方法,分析了晶体的二向色性对λ/4波片产生圆偏光、λ/2波片使偏振面产生旋转以及出射光振幅的影响,当线偏光光矢量与波片快轴成45°入射时,由于晶体的二向吸收,通过波片后的光不是圆偏光而是椭偏光,只有在满足条件时才能得到圆偏光,而且振幅变小;对于波片,考虑二向吸收后,线偏光光矢量的旋转不再是入射光矢量与波片快轴夹角的2倍关系,光矢量的旋转角度和振幅的变化是二向吸收系数及入射光矢量与晶体光轴夹角的函数。结果表明,晶体的二向色性对波片性能的影响是不容忽视的,在器件使用中应该引起人们的注意。     

Polymer Planar‐Lightwave‐Circuit‐Type Variable Optical Attenuator Fabricated by Hot Embossing Process

A polymer‐based planar‐lightwave‐circuit‐type variable optical attenuator (VOA) was fabricated using a hot embossing process. With an optimized one‐step embossing process, forty micro‐channels for the guidance of light were defined on a polymer thin film with an accuracy of ° 0.5 µm. The fabricated polymeric thermo‐optic VOA shows 30 dB attenuation with 110 mW electrical input power at 1.55 µm. The rise and fall times are less than 5 ms.     

Synthesis and opto-electrical properties of Cu2NiSnS4 nanoparticles using a facile solid-phase process at low temperature

Cu2NiSnS4 nanoparticles were prepared for the first time using a facile solid-phase process at a temperature of 180 °C. The crystalline structure, morphology and optical properties of the Cu2NiSnS4 nanoparticles were characterized by means of X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM) and ultraviolet-visible (UV-vis) spectrophotometer. The band gap and conversion efficiency of Cu2NiSnS4 nanoparticles were studied at various temperature. The results showed that the Cu2NiSnS4 nanoparticles exhibited an optimum band gap of 1.58 eV and a conversion efficiency of 0.64% at 180 °C, indicating that it maybe be useful in low-cost thin film solar cells.