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1.
超高速摄影中蜂窝结构转镜的设计与力学分析   总被引:1,自引:0,他引:1       下载免费PDF全文
 提出了蜂窝结构的三面体转镜,对这种新型转镜做了结构设计,并利用3维有限元计算技术,分析了蜂窝结构的三面体铝合金转镜的力学性能。结果表明:对镜面尺寸17.325 mm、轴向长度32.5 mm的三面体铝合金转镜,在5×10 4 r/min转速下,镜面最大变形量为0.547 μm,约为原结构铝合金转镜镜面的16%,与相同结构尺寸的铍转镜镜面变形量处于相同量级;内部最大应力小于原结构铝合金转镜。  相似文献   

2.
扫描式超高速摄影中转镜镜面变形量的几何补偿   总被引:2,自引:1,他引:1  
利用三维有限元计算技术,分析了从三面体到八面体铝合金转镜镜面变形规律.发现以四面体为界,三面体转镜镜面变形为向内凹进,五面体及以上转镜镜面则向外凸出.在对镜面变形定量分析基础上,提出了镜面变形的几何补偿方法,即采用柱面代替平直镜面,使镜面变形后的位置趋近于平直.结果表明,对镜面尺寸17.32 mm,轴向长度32.5 mm的三面体铝合金转镜,在5×104 rpm下,镜面最高点偏离平直镜面的最大值为0.468 μm,是平直镜面的1/9,与相同结构尺寸的铍转镜镜面变形量处于相同量级.说明铝合金转镜采用几何补偿方法,可以在扫描式摄影系统中代替铍转镜.  相似文献   

3.
超高速摄影中弹性支撑转镜的模态分析   总被引:3,自引:2,他引:3       下载免费PDF全文
 提出了超高速摄影仪中弹性支撑转镜模态分析方法,利用有限元法对三面体铝合金转镜刚性支撑和弹性支撑情况下的一、二阶模态进行模拟,结果表明:电驱动转镜在转速工作范围内只有2个临界点,分别位于2.5×105~2.6×5 r/min和2.6×105~2.7×105 r/min处, 并且均为一阶弯曲振动,一阶模态振动发生在垂直平面内,二阶发生在水平平面内。将模拟结果与实测值进行了比较,发现假设转镜为弹性支撑与实测值吻合得较好。  相似文献   

4.
Amorphous SiO2 thin films with about 400—500 nm in thickness were thermally grown on single crystalline silicon. These SiO2/Si samples were firstly implanted at room temperature (RT) with 100 keV carbon ions to 2.0×1017, 5.0×1017 or 1.2×1018 ions/cm2, then irradiated at RT by 853 MeV Pb ions to 5.0×1011, 1.0×1012, 2.0×1012 or 5.0×1012 ions/cm2, respectively. The variation of photoluminescence (PL) properties of these samples was analyzed at RT using a fluorescent spectroscopy. The obtained results showed that Pb-ion irradiations led to significant changes of the PL properties of the carbon ion implanted SiO2 films. For examples, 5.0×1012 Pb-ions/cm2 irradiation produced huge blue and green light-emitters in 2.0×1017 C-ions/cm2 implanted samples, which resulted in the appearance of two intense PL peaks at about 2.64 and 2.19 eV. For 5.0×1017 carbon-ions/cm2 implanted samples, 2.0×1012 Pb-ions/cm2 irradiation could induce the formation of a strong and wide violet band at about 2.90 eV, whereas 5.0×1012 Pb-ions/cm2 irradiation could create double peaks of light emissions at about 2.23 and 2.83 eV. There is no observable PL peak in the 1.2×1018 carbon-ions/cm2 implanted samples whether it was irradiated with Pb ions or not. All these results implied that special light emitters could be achieved by using proper ion implantation and irradiation conditions, and it will be very useful for the synthesis of new type of SiO2-based light-emission materials.  相似文献   

5.
A method with scanning electron microscopy (SEM) is presented to measure the density inhomogeneity of the stainless steel (SS316) sphere prepared for measuring G using time-of-swing method. The experimental result shows that the relative density inhomogeneity of the sphere is better than 5.9×10-4 over the volume of 0.272×0.234×0.005mm3. If we assume that the density inhomogeneity of the spheres used in our G measurement is the same as that of the sphere destroyed in testing, it will contribute to G value with an uncertainty of less than 0.034ppm in our G measurement. Furthermore, the mass centre offset from the geometric centre of the sphere will be less than 4.3×10-4,μm due to this inhomogeneity.  相似文献   

6.
To investigate the configurations of the valence protons in Borromean nucleus 17Ne, a CsI(Tl) detector array, which consists of 9 CsI crystals (26×26×20mm3) coupled with photodiodes, has been successfully used in the 17Ne experiment to measure the energy of protons. In order to find the optimal working conditions and get the best energy resolutions, several technologies (including various wrapping materials, wrapping and coupling methods) have been used. The testing results showed that the best energy resolution of the CsI(Tl) is about 3.3% using the 241Am α-source. The primary testing results with the proton beam were also provided.  相似文献   

7.
Based on 58 million J/ψ events collected by the BESⅡ detector at the BEPC, J/ψ→ΛΛ π+π- is observed for the first time. The branching fraction is measured to be Br(J/ψ→ΛΛ π+π-)=(4.30±0.13±0.99)×10-3, excluding the decays to intermediate states, namely J/ψ→Ξ-Ξ+, J/ψ→Σ(1385)-Σ(1385)+, and J/ψ→Σ(1385)+Σ(1385)-. The branching fractions for these intermediate resonance channels are measured to be:Br(J/ψ→Ξ-Ξ+)=(0.90±0.03±0.18)×10-3, Br(J/ψ→Σ(1385)-Σ(1385)+)=(1.23±0.07±0.30)×10-3,and Br(J/ψ→Σ(1385)+Σ(1385)-)=(1.50±0.08±0.38)×10-3, respectively. The angular distribution is of the form dN/d(cosθ)α(1+αcos2θ) with α=(0.35±0.29±0.06) for J/ψ→Ξ-Ξ+, α=(-0.54±0.22±0.10) for J/ψ→Σ(1385)-Σ(1385)+, and α=(-0.35±0.29±0.06) for J/ψ→Σ(1385)+Σ(1385)-.  相似文献   

8.
红外用CVD ZnS多晶材料的研制   总被引:1,自引:0,他引:1  
论述了制备红外用CVD ZnS多晶材料的化学气相沉积工艺和热等静压处理工艺。针对CVD ZnS多晶材料具备优良的光学和力学性能,采用化学气相沉积工艺和热等静压处理技术成功研制出大尺寸多晶材料,其最大尺寸达到250mm×15mm。测试了CVD ZnS样品的各项光学、力学性能指标。样品的全波段透过率均接近ZnS材料的本征水平,折射指数均匀性优于2×10-5,在1.06μm的吸收系数为2×10-3cm-1,抗弯强度达到104MPa。  相似文献   

9.
Single-crystalline Si (100) samples were implanted with 30 keV He2+ ions to doses ranging from 2.0×1016 to 2.0×1017ions /cm2 and subsequently thermally annealed at 800℃ for 30min. The morphological change of the samples with the increase of implantation dose was investigated using atomic force microscopy (AFM). It was found that oblate-shaped blisters with an average height around 4.0nm were found on the 2.0×1016 ions /cm2 implanted sample surface; spherical-shaped blisters with an average height around 10.0nm were found on the 5.0×1016 ions /cm2 implanted sample surface; strip-shaped and conical cracks were observed on the sample He-implanted to a dose of 1.0×1017 ions /cm2. Exfoliations occurred on the sample surface to a dose of 2.0×1017 ions /cm2. Mechanisms underlying the surface change were discussed.  相似文献   

10.
Thermally grown amorphous SiO2 films were implanted at room temperature with 100 keV C-ions to 5.0×1017 or 1.2×1018 ions/cm2. These samples were irradiated at room temperature with 853 MeV Pb-ions to 5.0×1011, 1.0×1012, 5.0×1012 ions/cm2, or with 308 MeV Xe-ions to 1.0×1012, 1.0×1013, 1.0×1014 ions/cm2, respectively. Then the samples were investigated using micro-Raman spectroscopy. From the obtained Raman spectra, we deduced that Si--C bonds and sp2 carbon sites were created and nano-inclusions may also be produced in the heavy ion irradiated C-doped SiO2. Furthermore, some results show that Pb ion irradiations could produce larger size inclusions than Xe ions and the inclusion size decreased with increasing the irradiation fluence. The possible modification process of C-doped a-SiO2 under swift heavy ion irradiations was briefly discussed.  相似文献   

11.
高速扫描相机时间测量不确定度分析   总被引:21,自引:6,他引:15  
谭显祥 《光子学报》2002,31(11):1387-1390
以国内普遍使用的SJZ-30型高速扫描相机为例,用精测转速方法的结果处理数据,转速测量相对合成不确定度小于0.1%,时间间隔测量的相对扩展不确定度为0.2%.扫描速度在像面上的位置误差,采用"中值扫描速度",可予以校正.同时讨论了进一步降低转速测量不确定度和位置误差的方法.  相似文献   

12.
谭显祥  黄福 《光子学报》1988,17(1):64-67
本文介绍了转镜式高速相机在爆炸实验中的应用情况。阐明了这些相机使用时配备的各种主要附加装置,并举例说明了所得到的实验结果。  相似文献   

13.
黄福 《光子学报》1991,20(4):418-422
高速动光弹仪是动态光弹性研究的有效诊断工具,主要用于记录各种结构在动载荷作用下,不同瞬间的应力条纹图像。研究应力波的传播规律,裂纹扩展过程,固体高速变形等。通常的动光弹仪为多火花式动光弹仪。国外也有采用静态光弹仪与转镜式高速分幅相机结合的系统。我们研究调试的动光弹系统,是在高速纹影系统中加入偏振光场,即静态光弹系统、纹影系统与转镜式高速分幅相机结合。在雷管动载荷作用下,应用高压脉冲氙灯光源,单色圆偏振光亮场,获得了不同光弹模型的清晰应力条纹图像。给出应力波的传播过程和孔附近产生的应力集中现象。该系统具有摄影频率高、曝光时间短、测试灵敏度高、适于强载荷、远距离研究大尺寸光弹模型,同时具有透射式和反射式光学系统等特点。从而为动态光。弹性研究提供了有效的测试技术和诊断系统。  相似文献   

14.
用超高速阴影摄影技术研究微喷射现象   总被引:2,自引:0,他引:2  
以转镜式高速分幅相机作为记录载体,设计并建立了高速阴影系统。用该摄影系统研究在爆轰加载下金属表面的微喷射现象,以及由此产生的波阵面发展过程。通过获取的阴影图像观察到了带有特定形状缺陷(矩形槽、盲孔)锡自由表面的微喷射演变过程,给出了微射流的形状,冲击波阵面以及喷射物头部的运动速度等物理信息。  相似文献   

15.
台伟  刘家齐 《光子学报》1989,18(2):131-138
研究金属切削过程中的变化,对改进切削工艺、实现高速、自动化和精密加工具有重要意义。高速显微摄影是实现从宏观到微观、从定性到定量、从静态到动态研究的有效方法。  相似文献   

16.
肖刚  张建泉 《光子学报》1997,26(6):537-545
本文改进了传统的辐射流体动力学模型,建立了完整的一维单流体双温度辐射流体力学方程组描述5×108w/cm2高斯脉冲激光与一维半无界铝靶在真空中耦合所产生的靶外等离子体的发展过程,并建立了相应的数值模拟模型,计算结果与有关文献和实验比较,取得了定性与定量的一致.  相似文献   

17.
The cw output power of the uv CuII laser has been optimized with respect to the hollow cathode geometry, the discharge current, the fill gas pressure and the resonator mirror parameters. A maximum laser output power of 900 mW for multiline operation at 248.6, 259.1, 260.0, and 270.3 nm was achieved with 100 A discharge current, 260 V voltage and 16 mbar fillgas pressure, when a hollow cathode of 1.2 m length and 2×6 mm2 cross section was employed. The single-pass pain gl has been estimated to 7%. A hollow cathode cross section of 1.5×4.5 mm2 is suggested as an optimum geometry. In addition, some investigations on the mechanism of the laser power decay in Ne–Cu-discharges are presented.  相似文献   

18.
针对铝合金材料,设计了大口径红外相机主反射镜,反射镜口径420 mm。以径厚比、支撑点数量和轻量化结构形式为输入点,设计了一种背部开放式、三角形轻量化结构和背部3点支撑的结构形式。通过有限元分析软件对反射镜的动态刚度及自重和温度载荷下的面形变化进行了分析。分析结果表明:反射镜具有高的动态刚度,反射镜自重工况和-40 ℃均匀温降下,面形精度RMS分别为30 nm和0.2 nm,均满足光学设计提出的/10(=632.8 nm)指标要求,为大口径铝合金反射镜的设计提供了理论依据。  相似文献   

19.
康玉思  刘伟奇  冯睿 《应用光学》2007,28(4):401-405
为了满足机械转镜扫描要求(转镜转速每分钟不少于3万转)及光束与水平信号的行场同步要求,提出采用面阵空间光调制器及多像素并行扫描方式。采用“面阵空间光调制器”对激光束进行选通和光强调制,使覆盖多像素的激光束在高速扫过面阵空间光调制器时,光强按视频图像的强弱进行调制,从而形成激光视频图像。由于采用了多像素并行扫描、新型二维扫描转镜和积分器光路,扫描速度大大降低,由每分钟几万转降低到3000转,解决了扫描式激光显示的技术瓶颈和激光干涉条纹问题,获得了很好的显示效果。  相似文献   

20.
黄涛  谭显祥 《光子学报》1989,18(3):251-257
本文采用数字图象处理技术,最小二乘法曲线拟合原理和计算机图形学原理,对铝板在点爆驱动下的高速云纹图象(拍摄频率为5×104ps)进行计算机数据处理, 重建了铝板在不同时刻的三维形状, 并使高速投影云纹技术的测量精度达到了±5%。  相似文献   

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