红外双色诱饵剂性能测试研究

为了对抗目前广泛应用的红外双色(1~3和3~5μm)制导系统,设计制备了一种能够模拟真实目标红外双波段辐射特性的新型红外双色诱饵剂,采用Imager IR8325中波红外热像仪测试其燃烧过程中的温度变化情况以及特定时刻的火焰温度分布;采用SR5000光谱辐射计、Tensor37遥感红外光谱仪测试红外双色诱饵剂静态光谱辐射特性,获得了其频域和时域特性,分析了双色诱饵剂辐射强度和红外中近颜色比的影响因素;同时为了研究高速飞行状态下双色诱饵剂的辐射强度和颜色比变化规律,采用直路式等速负压气溶胶风洞进行了诱饵剂动态辐射强度测试,解释了红外双色诱饵剂辐射特性在高速气流影响下与传统诱饵剂不同的衰减机理。实验结果表明,该双色诱饵剂火焰温度在850~1 100℃之间,与真实目标具有较为接近的温度特征,该诱饵剂的红外中近比为1I3~5μm∶I1~3μm3,3~5μm红外辐射强度为(1.1±0.1)kW·sr-1,与真实目标具有较为接近的红外光谱辐射特征,是一种性能优良的双色诱饵剂。     

一种新型红外/紫外双色诱饵剂的光谱辐射特性研究

传统MTV型红外诱饵(以镁粉、聚四氟乙烯、氟橡胶为基本组分)的优点是其红外辐射总能量很高,可有效对抗传统热源寻的导引头。依靠燃烧高温产生光谱辐射的MTV诱饵,紫外波段和近红外波段辐射强度很高,红外中波段的辐射强度相对较低,而真实战斗机的紫外波段辐射强度较低,且其红外中近比一般大于1,因此,传统的MTV型诱饵无法对抗红外/紫外双色复合制导系统。根据光谱匹配原理设计制备了一种新型红外/紫外双色诱饵剂,基本组分为45%~75%的氧化剂(A1/A2)、10%~25%的燃料(B1/B2/B3)、25%~50%的含能粘合剂(C1/C2/C3)以及添加剂(D),使用CEA软件对药剂配方的燃烧产物进行了理论计算,通过计算结果初步确定诱饵剂配方中各个组分的含量;采用SR5000光谱辐射计、Tensor37遥感红外光谱仪测试其红外光谱辐射特性,并分别从测试原理和计算方法、测试环境的差异性以及测试结果的稳定性等方面分析了两种仪器测试获得的结果存在差异性的可能原因;采用S2000光纤光谱仪测试其紫外光谱辐射特性,测试结果与通过理论计算获得的战斗机紫外辐射强度较为吻合;采用Imager IR8325中波红外热像仪测试其燃温特性,结果表明该双色诱饵剂与真实目标具有较为接近的温度特征。实验结果表明,该诱饵剂的红外中近比为1I3~5μm∶I1~3μm3,3~5μm红外辐射强度在0.9~2.5kW·sr-1范围内可调,0.3~0.5μm波段紫外辐射强度约为(20±5)W·sr-1,火焰温度在850~1 100℃之间,是一种性能优良的双色诱饵剂。     

红外诱饵的辐射特性及在光电对抗系统中的作用

介绍了红外诱饵的辐射特性及在光电对抗系统中的作用，给出两类诱饵的光谱辐射特性曲线、光谱辐射数据表、红外热辐射特征、时域变化特性曲线等，指出诱饵弹的发展趋势。     

H_2O和CO_2高温混合气体喷流红外辐射特性

利用数值仿真方法研究了H_2O和CO_2高温混合气体喷流的红外辐射特性。根据H_2O和CO_2两种气体的吸收特性,将红外波段划分为1.32~1.69μm、1.56~2.27μm、2.27~3.8μm、3.8~8.3μm和8.3~20μm五个波段。建立了基于某型发动机喷嘴的尾流红外辐射特性模型,并利用此模型分别研究了H_2O和CO_2高温混合气体喷流在这五个波段的辐射特性分布。仿真结果表明,喷流中H_2O含量越高,越有助于能量的扩散,因此喷流温度和辐射能量也越低;在高温喷流的辐射特性中,中波红外波段辐射能量最强,长波红外波段的最弱。     

海天目标三维实时红外场景仿真

提出了一种海天目标三维实时红外场景的仿真方法。首先建立了场景的3D物理模型,然后根据黑体辐射理论分别计算出背景与目标的红外辐射特性。考虑到气温对成像的影响,以及探测器分别对3～5μm与8～12μm波段的响应率,根据物体的表观温度对视场内的红外图像进行显示。最后将背景与目标进行融合得到最终的仿真场景。通过提出的方法对海面...     

涡扇发动机轴对称塞式喷管红外辐射特征计算

用数值模拟的方法研究了3～5μm波段涡扇发动机轴对称塞式喷管的红外辐射特性,并与轴对称收扩喷管进行了对比。结果表明:轴对称塞式喷管红外辐射的空间分布和光谱分布特性方面与轴对称收扩喷管具有相似的特征,但是在红外辐射强度的数值有较大差别;以轴对称喷管为基准,轴对称塞式喷管无冷却措施的情况下尾向0°～15°范围内能够降低红外辐射强度,但在其他方向上的辐射强度有所增强;塞锥后部壁面冷却至400K,在0°～90°方向上塞式喷管均能有效降低红外辐射,且0°方向上降低了40.4%。大气对红外辐射的吸收作用随着探测角度的增大而增强。     

蛋白石型光子晶体红外隐身材料的制备

基于光子晶体的红外隐身材料,主要采取一维层层堆叠结构和三维木堆结构等来实现对红外波段电磁波辐射性能的调控.本文报道了一种操作简易、成本低廉的光子晶体红外隐身材料制备方法.通过优化的垂直沉积法,微米级SiO_2胶体微球自组装成高质量的蛋白石型光子晶体结构.对SiO_2胶体微球进行优选,成功制备了禁带位于2.8—3.5μm,8.0—10.0μm的SiO_2胶体晶体蛋白石型光子晶体材料.该材料可改变目标相应波段的红外辐射特征,具有目标红外波段的隐身效果.     

近中红外与1.06μm和1.54μm激光兼容隐身光子晶体研究

为实现飞行器高温部分的红外与激光兼容伪装,设计了一种基于一维光子晶体的近中红外与1.06μm和1.54μm激光兼容隐身材料。基于薄膜的传输矩阵法和异质结构理论,拓展了光子晶体的禁带宽度,使之覆盖近中红外波段;随后,利用掺杂原理,在光子晶体周期结构中引入了两种缺陷。结果显示,在1~5μm的带隙中出现了波长分别为1.06μm和1.54μm的缺陷模,反射率分别为1.21%和1.79%,这种具有"光谱挖空"特性的光子晶体可以实现近中红外与1.06μm和1.54μm激光兼容隐身。     

高温二氧化碳气体红外辐射实验研究

主要介绍了依托高频等离子体风洞建立的高温气体辐射测量平台,并在此平台上开展了高温二氧化碳气体红外辐射实验测量。介绍了高频等离子体风洞的运行原理、流场特性及工作介质;介绍了实验测量的条件、装置、标定、数据处理方法和结果分析;通过自建的高温气体发射光谱测量平台实验测量了二氧化碳气体在1 500~3 000K范围内4个温度点的红外发射光谱;介绍了Abel变换在测量二氧化碳气体红外辐射空间分布中的应用,通过Abel变换获得了高温下二氧化碳气体红外辐射的空间分布结果;分析了高温二氧化碳气体在4.3μm附近的红外辐射的强度及其中心波长随温度变化的分布,得到了发射峰中心波长随温度的升高向长波方向展开的结果,并与文献结果进行了对比分析。     

基于光谱分析的油料池火内部传热特性研究

油料池火焰内部分为不同燃烧区域,目前对油池火内部传热特性研究较少。针对油池火内部传热特性研究不足的现状,构建了红外火焰光谱测试系统,研究分析了92#汽油、95#汽油及润滑油池火焰红外光谱特性,对油池火焰不同燃烧区域的光谱信息进行了提取分析,结果表明:三种油料池火焰光谱特征相似,存在多个CO2,H2O及炭黑颗粒等燃烧产物的特征发射波段,3.4μm处C—H伸缩振动峰明显;火焰烟气区主要光谱特征为4~4.5μm波段范围内高温CO2发射峰,该区域火焰与空气换热剧烈,温度变化不稳定,火焰脉动频率较高;火焰间歇区的光谱特征是4~4.5μm波段范围内高温CO2发射峰,与烟气区相比,火焰间歇区脉动频率相对较低;与烟气区及间歇区相比,火焰连续区燃烧较为稳定,该区域的光谱特征明显,在2.5~3μm波段范围内炭黑粒子发射光谱强度较高,且在3.4μm处存在C—H伸缩振动峰,表明油料池火焰光谱3.4μm处的特征峰由高温油蒸汽产生。油池火焰不同燃烧区域光谱特征分析表明,油池火焰液态油表面的"富燃料层"吸收火焰传热,引起3.4μm附近油蒸汽分子能级的改变。油池火焰不同燃烧区域发射光谱强度计算表明,火焰连续区的强度最大,其次为间歇区,火焰烟气区与空气对流强烈,测得的发射光谱强度最低。研究结果为火焰—油料传热模型的修正提供了参考。     

Infrared facility at the Canadian light source

The Canadian Light Source (CLS) is constructing two beamlines for Infrared Spectroscopy using synchrotron radiation (IRSR). One will supply mid-Infrared (2–25 μ) light to a Fourier Transform Infrared (FTIR) spectrometer and microscope for biological applications. The second will have a high resolution FTIR spectrometer for gas-phase and surface spectroscopy in the far-Infrared (beyond 25 μ). The Infrared beamlines will use dipole bending magnet radiation from a special bend magnet port design which provides a 50 mrad square acceptance. Issues with the first mirror and photon mask design, as well as the beamline layout and features are discussed.     

Characterization of solid state array cameras for the mid-IR

We present a characterization of some processes affecting the performance of solid state array cameras designed for ground based astronomical imaging in the 8–13m atmospheric window. Our discussion includes a novel model for electron-hole generationrecombination noise based on the probable pathlength of an electron in a photoconductor. We use the Berkeley mid-IR Array Camera as an example. For this camera, the results show that the total optical system composed of the camera, a 3m telescope, and the atmosphere has an efficiency of about 3%, a 1 noise equivalent flux density of 25 mJy min^–1/2arcsec^–2 measured over a /=10% band width, and a noise equivalent expressed as the ambient temperature thermal black body noise of 23%.     

Vibrational Spectra of Ethylenediamine Salts. I. Tentative Assignments of Infrared and Far Infrared Spectra

Abstract

We wish to report on some hitherto partly unnoticed and unexplained features in the infrared spectra of hydrogen halides of ethylenediamine. We have prepared normal, C-, N-, and perdeuterated ethylenediammonium chlorides and bromides and measured their infrared spectra in the range 4000–10 cm^?1.     

Dynamic infrared scene projection: a review

Since the early 1990s, there has been major progress in the developing field of dynamic infrared scene projection, driven principally by the need for hardware-in-the-loop simulation of the oncoming generation of imaging infrared missile seekers and more recently by the needs for realistic simulation of the new generation of thermal imagers and forward-looking infrared systems. In this paper the current status of the dynamic infrared projection field is reviewed, commencing with an outline of its history. The requirements for dynamic infrared scene projection are examined, allowing a set of validity criteria to be developed. Each class of infrared projector that has been investigated—emissive, transmissive, reflective, laser scanner and phosphor—together with the specific technology initiatives within the class is described and examined against the validity criteria. In this way the leading dynamic infrared scene projection technologies are identified.     

基于非均匀B样条曲线的红外数据的精确拟合及校正

红外谱图数据的精确拟合是建立标准谱图的重要组成部分,是光谱仪器正确进行定性和定量分析的基础.文章采用非均匀B样条对红外谱图数据进行曲线拟合,通过采用基于最大范数距离的B样条拟合算法,不仅解决了大容量红外谱图的精确拟合问题,同时对谱图峰值精确定位也提供了方便.文章介绍了非均匀B样条曲线,以及二阶(三阶)非均匀B样条曲线拟合的实现,重点描述了红外谱图数据拟合精度的控制方法.     

Raman Spectra of Porphyrins

The spectroscopy of porphyrins has been developing rapidly during the last two decades, this class of compounds being of great biological importance and possessing a number of significant properties. Different spectroscopic techniques, viz., electronic spectroscopy including fine-structure quasiline spectra (Shpolsky effect), infrared spectroscopy, luminescence, flash photolysis, ESR and NMR spectroscopy etc., have been applied to the study of these molecules (see reference ¹ for a review). However until recently there were no publications on Raman spectra of porphyrins and related compounds although it is evident that a complete analysis of molecular vibrations is impossible without knowing the Raman frequencies, especially for centrosymmetrical molecules. We have obtained Raman spectra of two porphin derivatives, viz., copper and nickel octamethylporphin ² which seems to be, together with data on hemoglobin and cytochrome^3-5 and on chlorophylls ⁶, the first observation of Raman spectra of porphyrins. In this paper Raman spectra of several metalloporphyrins are presented including metal complexes of porphin, octamethylporphin, etioporphyrin I, meso-tetraphenylporphin and tetrabenzporphin. For some of them Shpolsky spectra have been obtained and a juxtaposition is made of the two kinds of spectral data concerning the frequencies of molecular no- modss. Also some data of infrared spectra are presented.     

IR signature estimation of an object or a target by taking into account atmospheric effects

In this study, a reference infrared (IR) image of an object or a target was analyzed, and the IR signature was calculated. Background and atmospheric effects were decomposed so that the calculation errors were minimized. Depending on the reference IR image, the IR signature at any distance and any angle was estimated while considering atmospheric effects. Calculated results were obtained from IR images taken from the same distance and angle, and were compared with the estimated results. The comparison of the measured and calculated signatures demonstrated the accuracy of the proposed method of estimation.     

Study on Infrared Spectral Radiance by Remote Fourier Transform Infrared Spectroscopy

Abstract

Infrared emission spectra emitted by high luminosity infrared pyrotechnics have been observed remotely using the Fourier transform infrared spectroscopy. The primary purpose of the study is to determine infrared spectral radiance distribution, their time—resolved spectra and integrated emission energy. The spectra have been recorded between 4000 – 800cm^?1 region with spectral resolution of 4cm^?1. The study is very important for many applications.     

Design of midwave infrared athermalization optical system with a large focal plane array

Based on the most advanced staring focal plane array which had a format of 640 × 480 and the pixel pitch of 15 μm, a set of all-sphere midwave infrared ahermalization optical system was designed. The working wavelength was in 3–5 μm, the full field of view was 8.58°, the relative aperture was 1/2, the efficient focal length (EFL) was 80 m. The opticalsystem consisted of four lenses with three kinds of material – Ge, ZnSe and Si. All surfaces were sphere, which was easier to process test, making the cost inexpensive, and it could avoid using diffractive surface and aspheric surface. The image quality of the system approaches the diffraction limit in the temperature range −60 °C-180 °C. The design results proved that, the high resolution midwave infrared optical system had compact structure, small volume, high resolution and excellent image quality, meeting the design requirements, so that it could be used for photoelectric detection and tracking system.     

Single- and multi-photon absorption of carbon dioxide laser lines by SO2 and CO2 molecules

Summary We have used 60 rovibrational lines of a Lumonics TEA CO₂ laser to record the spectra of coincidence of SO₂ IR absorption with CO₂ laser emission. We extended the same type of investigation to CO₂ molecules and observed an absorption at practically all the rovibrational lines of the laser. We have also recorded the increase of absorption with pressure of the studied molecule and with its temperature. Our work reveals very accurately the fine structure of these absorptions that shows a clear discreteness in the intensities of the lines. Some implication of this discreteness in multiphoton absorption is also presented, through data that indicate very strong vibrational coupling between ground and excited electronic states of SO₂. The authors of this paper have agreed to not receive the proofs for correction.