纤维基低发射率隔热材料制备研究

兼具表面低红外发射率和隔热性能的功能纺织材料在工业及军事领域有着广泛用途。从利用低表面发射率和控制物体表面温度两方面,研究制备具有低红外发射率且隔热性能良好的功能材料。选用聚丙烯酸酯(PA)作为成膜粘结物质,研究了铝粉的粒径及用量对涂层红外发射率的影响;以不同的空心微珠为隔热填充剂,并对其用于涂层织物的隔热效果进行探究。最后,将低发射率涂层与隔热涂层进行复合,制备出兼具低发射率与隔热性能的材料。结果表明,采用400目片状铝粉时的发射率比采用600目时更低,20%的400目片状铝粉的涂层胶所制备的涂层表面的红外发射率低至0.237。由于空心微珠是较好的隔热填料,以共混15%的玻璃微珠为隔热层,以共混20%的400目片状铝粉为低红外发射率涂层,所制备的纤维基复合涂层材料的发射率为0.507,热体试样与背景温差为3.75℃,具有较好的隔热性能和低红外发射率。     

微米Al/PS复合粒子的制备及红外发射率性能分析

采用油酸对铝粉表面进行亲油性改性,利用原位分散聚合法制备Al/PS复合粒子.采用SEM、XRD和FTIR对复合粒子的结构进行了表征,同时还测定了复合粒子的红外发射率.研究结果表明:PS包覆后的铝粉经过4个月长时间保存后仍有很好的防氧化能力,而且红外发射率比没包覆的铝粉降低约0.13.     

聚氨酯基红外-激光兼容隐身涂层性能研究

以三氧化二铬包覆片状铝粉粒子(Al/Cr2O3)为填料,聚碳酸酯基水性聚氨酯为粘合剂,涂敷于玻璃片上,自然干燥制得涂层。研究了粘合剂、填料及它们的加入量对涂层红外发射率和激光反射性能的影响。采用红外发射率测量仪和可调谐CO2激光器测试涂层在8～14μm红外发射率和10.6μm激光反射性能。结果表明:使用的粘合剂较普通水性聚氨酯发射率低,固定粘合剂量,改变填料加入量,涂层在8～14μm波段发射率和10.6μm激光的反射性能都随着包覆粒子的增加而减小,当加入量达到30%时,涂层的红外发射率可以降低至0.688,激光反射能量降至初始入射能量的1%,且涂层综合物理性能良好,达到红外—激光兼容隐身的要求。     

石蜡基复合相变材料制备及低红外辐射表征

以石蜡为相变材料,A1粉为填料,制备出在红外波段具有较低辐射能量的复合相变材料,并对复合相变材料的结构、热性能和红外发射率进行了表征.结果表明:添加40%A1粉的石蜡基复合相变材料的红外发射率可低至0.2,此材料的相变温度是49.8℃,其相变潜热是121.47J/g.采用试板法测试了相变材料石蜡控温效果,并将控温结果与理论计算相结合.计算结果表明,添加40%的A1粉得到的复合石蜡相变材料可以在理论上使其辐射能量至少降低85%.     

低发射率材料涂敷区域对排气系统壁温和红外特性的影响

为了研究红外低发射率材料涂敷区域对排气系统壁温和红外特性的影响,在相同实验工况下,实验测量了3种涂敷方案:(1）仅中心锥涂敷;（2）仅混合器内表面涂敷;（3）中心锥与混合器内表面同时涂敷。下轴对称和S弯二元排气系统壁温和红外辐射特性。结果表明:涂敷低发射率材料将导致表面温度升高,同时也影响排气系统非涂敷区域的壁面温度分布。高温部件涂敷低发射率材料时,在涂敷区域可被直接探测的角域内,可有效抑制排气系统的红外辐射,但在涂敷区域不能被直接探测的角域内其影响规律因涂敷方案而变,在3种涂敷方案中,S弯二元排气系统仅涂敷混合器内表面,轴对称排气系统中心锥和混合器内表面同时涂敷低发射率材料时整体红外抑制效果最好。     

红外隐身涂料发射率的影响因素研究

介绍了红外隐身涂料发射率测试的原理及方法,同时,讨论了基底(基底材料和基底颜色)、涂刷次数、涂层表面粗糙度、老化时间对红外发射率值的影响,结果表明:红外隐身涂料的发射率随着基底发射率的增大、涂刷次数的增加和老化时间的延长而增大;光滑表面涂层的红外发射率要低于粗糙表面涂层的红外发射率.     

红外发射率控制方法及机理研究

红外发射率的控制具有广泛的用途,根据电磁波理论,讨论了物体表面的发射率与折射率的关系,折射率大的物体发射率低.电致变色材料是一种可控制其表面折射率和发射率的材料.以氧化钨为例探讨了发射率的控制方法.利用电场对三氧化钨薄膜进行离子和电子的共注入和共抽取,三氧化钨中的载流子浓度发生了变化,折射率和红外发射率也发生了变化.     

基于红外光谱偏振度对比度的涂层材质识别研究

为了降低材质红外识别的正确率,较常用的方法是通过在材质表面涂覆涂层,以改变材质的表面发射率。首先通过基于微面元理论的目标材质表面红外辐射偏振传输模型的Stokes表达式,推导分析了目标材质表面发射率对目标材质表面红外偏振特性的影响,结果表明:目标材质表面发射率的改变不影响其表面的红外线偏振度特征;其次,针对材质表面发射率与红外偏振特性的不相关性,文章提出基于光谱偏振度对比度检测涂层材质的方法,并通过相同基底不同表面发射率的涂层材质、不同基底相同发射率的涂层材质的红外高光谱偏振成像特性进行了验证分析,结果表明:改变涂覆材料表面发射率并不影响材质表面的红外光谱偏振度特征;基底材料不同,即使目标材质表面涂覆相同发射率涂层,其表面的光谱偏振度特性将比光谱辐射亮度具有更明显的差异性,研究成果可为红外伪装材质检测识别提供新的途径和方法。     

红外发射率调制技术研究

物体红外发射率的调制具有广泛的应用前景.从理论上研究了红外发射率的调制机理,给出了三种调制发射率的技术途径:机械式、半导体载流子调制和电化学式.机械式发射率调制技术是利用不同发射率的材料组合来进行调制,通过调整不同材料在表面所占比例来调整发射率.半导体材料可通过调制PN结中的自由电子浓度实现红外发射率的调节.电化学式调制可通过多层薄膜实现.通过电场控制器件中变发射率薄膜层的离子和电子浓度,实现器件红外发射率的调制.     

EPDM基涂层在8～14μm波段红外低发射率的研究

以三元乙丙橡胶(EPDM)为粘合剂,通过优化填料的种类、用量和形貌制备了在8～14 μm波段红外发射率为0.14的EPDM/Cu、EPDM/SS涂层.分别对涂层进行红外发射率、反射率、导电率测试,并采用红外吸收光谱(IR)、扫描电镜(SEM)对其进行结构、形貌表征,从涂层反射、电导率、化学结构、微观形貌等角度分析了涂层低发射率的形成机理.对低发射率涂层样品进行耐温性、附着力,硬度等测试表明该涂层的工程应用性能优良.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.