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激光加工温度场CCD检测中的温度标定 总被引:1,自引:0,他引:1
激光加工温度场的检测对实现激光加工智能化有重要的实用价值。根据比色测温原理,提出采用彩色CCD和计算机图像处理相结合检测激光加工温度场的实验方案,研究CCD比色测温的温度标定。采用BF1400和BBR1000型国家标准黑体炉作为温度标定仪器,用WV-CP474型CCD相机在标定温度范围700~1400 ℃时,每隔100 ℃拍摄黑体炉靶面图像。开发了基于VC++的温度场图像处理专用软件,并对CCD拍摄的图像进行处理,建立了温度与比色值的数学关系表达式,并给出了待定系数。结果表明:CCD测温数据与现行标准测温数据之间存在良好的对应关系,进一步发展后,可成为激光加工温度场检测的有效手段。 相似文献
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推导出了CCD像素点亮度和具有实物面的高温辐射体温度之间的关系。结合比色测温法,提出了一种基于面阵CCD图像的温度场检测方法。分别在普通煤炉和黑体炉上用一套经黑体炉标定过的测温系统进行测温实验,取得良好效果。通过比较热电偶测量值和本算法计算温度值,分析了本测温方法的误差产生原因。 相似文献
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多波长测温是一种先进的辐射测温技术,其原理是假定发射率光谱模型,利用测得的多波长辐射与波长发射率函数关系,求得目标的真温和发射率。多波长成像测温技术通过探测目标的多波长辐射图像信息,反演计算得到目标的温场分布。针对基于彩色CCD的多波长成像测温不能适应非线性光谱发射率模型、测温动态范围较窄等不足,提出了一种基于光阑处非等比例滤色分光的四波长无扫描成像测温方法,有效压缩了波段成像带宽,形成了四个窄波段的成像探测,适用于非线性光谱发射率模型目标宽动态范围温场测量。根据提出的测温方法研制了四波长成像测温仪。测温仪主要由窗口、中性衰减片、四色滤光片、光学物镜镜头、可见/近红外集成传感器、测量控制单元及软件等部分组成。测温仪软件由目标四个波长的单色成像图像,得到目标的真温温场分布。在激光加热条件下对800~2500 ℃目标高温温场进行了试验测试,测量结果与热电偶数据比对表明误差小于1%,具有较高的准确度和较好的动态范围适应性。 相似文献
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为解决高温辐射源和环境温度对红外测温的影响,提高极端工况下红外热像仪的测温精度,以红外辐射理论以及红外热像仪测温原理为基础,提出了一种将红外图像灰度与目标温度、环境温度和积分时间相结合的综合辐射温度反演方法,该方法实现了环境(镜头)温度与场景温度参量解耦,可以独立预估各参量变化所产生的探测器响应变化。首先对红外热像仪进行数据标定,标定时一般采用高精度面源黑体,之后通过计算面源黑体辐射亮度,利用黑体辐亮度和黑体灰度的线性关系,对黑体温度与黑体图像灰度值两组数据之间关系进行拟合,建立全环境温度和全积分时间的大范围温度反演匹配模型。最后在实验室环境下,分别用热像仪和基于灰度的温度反演模型对探测目标进行测温。经过实验验证,该反演模型在实验室环境下取得了较为良好的效果。 相似文献
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基于比色测温原理,论述了比色测温理论中的滤光片带宽,得出滤光片带宽对测温精度的影响很大,并不能简单的将峰值透过率波长代替整个带宽。然后通过考虑滤光片的带宽导出合理的比色测温算法,并通过实验证实此算法大大减小了测温误差。 相似文献
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目标到测试系统距离对红外测温精度的影响 总被引:1,自引:0,他引:1
为了提高红外测温精度、减小测温误差,研究了目标到红外系统的距离对红外测温的影响,采用非制冷红外焦平面阵列热像仪和标准黑体进行定标研究,实验结果表明黑体红外热图像的灰度均值随温度呈线性变化,随距离呈非线性变化的关系,利用红外热像仪探测面上照度与像方孔径角的关系,对测试距离的影响做出了合理的解释;比较了不同距离处测量温度与真实温度的差别,得出在近距离测温时,距离变化对测温影响较大,最大误差可达±5℃;在远距离测温时,测试距离在大范围内变化,对测温结果影响很小,误差在±0.02℃范围之内.实际测量距离与热像仪标定距离不同,也会引入测温误差,因此保持实际测温距离与校准距离相同以减小误差,或根据不同距离处表观温度与实际温度的差别,对表观温度修正,以提高测温精度. 相似文献
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本文介绍了一种中温黑体炉配用的简单适用的温度数字显示装置。它采用铂电阻作感温元件,非线性R-V转换电路进行线性化,三重积分型A/D转换,以四位数字进行温度显示。测温范围为73K到1000K,分辨率0.1K,精度为0.1%,并且附有炉温上限的设定和超温报警电路。黑体炉系统加装此显示装置后,提高了测温精度,简化了系统,方便了使用。 相似文献
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Michael Reilly 《半导体技术》2004,29(12)
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. 相似文献
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Thomas M.Trexler 《半导体技术》2004,29(5)
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. 相似文献
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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. 相似文献
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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. 相似文献
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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. 相似文献
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GU Min-fen LIANG Zhong-cheng WANG Ren-zhou DONG Xiang-mei ZHANG Pei-ming CHEN Jia-bi 《光电子快报》2008,4(2):150-152
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. 相似文献
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Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
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. 相似文献
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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. 相似文献
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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. 相似文献
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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. 相似文献