资助这项研究是由美国国家科学基金会（NSF CAREER奖CCF-0347303和NSF资助CCF-0541105）。笔者想感谢他们的智力贡献，乔恩月球JaroslavKřivánek的埃德加·委拉斯开兹的Armendariz，雅各布·文策尔，詹姆斯·哈维，苏珊·苏亚雷斯，埃利斯勒夫，约翰·赫曼森。康奈尔大学的球形龙门内置从杜安富尔克，马克Levoy，Szymon Rusinkiewicz的的设计。

当使用我们的方法来衡量一个样本，实验者必须决定一组摄像头和光线方向，并为每个组合的摄像头和光线方向，用不同的快门速度，相机会多次暴露。移动相机会需要附加的处理，因为它改变了的试样的视图，如在图像中看到，因此，我们通常使用的相机方向和更多数量的光源方向的一小部分。 在下面的详细协议，我们首先介绍如何执行测量与许多光源方向和一台摄像机方向，以及如何处理和可视化结果的数据（协议）。在的主要协议，它可以单独使用，也足以观察正在研究的现象的单一视图中，我们始终保持垂直于样品的摄像机视图（主例程在图1）。是必需的，当多个相机方向斜意见的样品可以变形，撤消移动相机的效果，从而完全对齐图像与规范垂直视图。为了计算这些经纱，进行额外的校准步骤，使用放置在样品周围的摄像头相对于​​样品的运动精确地确定目标的观察。协议的细节校准程序，并介绍如何选择参数和运行协议1多次从多个视图（中学例程，在图1）收集数据。最后，协议细节的其他步骤必须插入第一议定书纠正斜在数据处理过程中的意见。 1。测量散射光的入射方向（图1中的初级套路在球体的表面法线方向） <ol class="ualpha"><li>准备和安装要测量的对象<ol><li>准备薄有色金属安装板目标的环（ 如图2所示）所包围的一个半英寸口径的。 </li><li>准备的材料，以进行测量。如果测量羽毛，新郎的倒钩，以纠正任何解压缩或错位部分的pennaceous叶片。 </li><li>莱物体表面的（正面面对羽毛）对目标环的对面）的背面侧（板。 </li><li>中心板在½英寸光圈感兴趣的区域。 </li><li>奠定磁性膜具有5/8-英寸孔径对对象的背面侧（反向面对的羽毛）的片材，从而按物体单位对板。 </li><li>不剪切表面的膜的孔径的光圈板对齐。的平坦的表面钉扎的圆形孔的圆周周围，产生一个平面的宏观面与板的表面大致一致。 </li></ol></li><li>配置龙门<ol><li>找到中心龙门式坐标系统的原点的圆形光圈。 </li><li>龙门外手臂上放置一个光源。对准狭重点对象，确保光孔径均匀照亮所有光源角度。 </li><li>龙门手臂内侧放置一个摄像头。调整相机的距离和微距镜头的焦距的目标，直到环填充的传感器的宽度。 </li><li>校准的相机和灯臂的旋转运动（θ，φ）。校准的倾斜（θ）相对于该对象的表面的法线，使相机和灯泡是否与表面法线对齐时，θ= 0。校准相机的方位角（φ）的方位角的灯。的绝对方位角方向并不重要，因为所拍摄的图像可以被旋转后在协议。 </li></ol></li><li>配置相机的对​​焦和曝光<ol><li>罗塔TE的相机，直到对象是在放牧的角度观看。减少的F数，以尽量减少字段的深度（DOF），然后将焦点设置在光圈的中心平面。增加的F数的自由度增加，直到周围的光圈环的目标是关注的焦点。衍射和自由度诱导的模糊之间的妥协可能是必需的。 </li><li>剪辑的一种颜色标准安装板平贴。对于RGB图像使用一个的麦克白颜色检查。对于紫外 - 可见 - 近红外光谱测量使用的Spectralon。 </li><li> RAW格式拍摄的颜色标准。颜色通道乘数计算白平衡图像。 </li><li>查找跨越场景的动态范围，在最极端的观看和照明方向的包围曝光。 </li><li>对于每个支架的曝光时间，获取暗噪声图像传感器暴露的镜头盖。 </li></ol></li><li>获取测量入射方向从一个人烟稀少采样球体<ol><li>定位相机轴垂直于表面平面{θ，φ} = {0,0}。 </li><li>步骤的一系列均匀分布的球体上的位置，光线通过使用粗糙的采样（ 例如，小于500点）。 </li><li>对于在采样每个入射光方向: </li><li>捕获原始图像每次曝光时间，曝光支架。 </li><li>捕获一个单一的形象照亮相机安装闪光灯同步到一个相对较短的曝光时间来抑制龙门灯照明。 </li><li>前进到下一个入射光方向和重复。 </li></ol></li><li>从稀疏采样球体的过程测量<ol><li>使用dcraw的一个模式调试（文件），禁止其去马赛克功能，从RAW格式转换成灰度，16位，线性，PGM格式: <ol class="lalpha"><li>每个暗噪声暴露。 </li><li>每个接触的对象在每个入射光方向。 </li> &lt;/ OL&gt; </li><li>整合所有低动态范围（LDR）龙门灯照明下的灰度风险成一个单一的高动态范围（HDR）为每个入射光方向的彩色图像。 <ol class="lalpha"><li>减去相应的暗噪声图像从每个LDR曝光。 </li><li>去马赛克每个LDR曝光产生一个季度规模形象。 </li><li>白平衡每个LDR曝光使用的颜色通道乘数计算步骤1.C.3。 </li><li>合并暗噪声减去LDR成一个单一的HDR图像在每个像素位置，并通过所有的值相加除以曝光时间的总和，省略了曝光过度的像素从两笔款项的风险。 </li><li>商店半浮点精度和无损小波（PIZ），的压缩编码EXR格式的HDR图像。 </li></ol></li><li>如果摄像机的方向是不规范方向，或在测量运行的多个摄像机的方向设定的一部分（在图1中 ，二级例程ND协议2）: <ol class="lalpha"><li>转换的LDR灰度曝光的闪光照明的跟踪目标为每个入射光方向的去马赛克，一季度规模，LDR EXR格式彩色图像。 </li><li>按照协议使用闪光照明图像投影每个HDR灯照式图像转换到规范的视图。 </li></ol></li><li>旋转的HDR图像转化为所需的方向- 例如，在我们的案例中，90°旋转定位羽轴和垂直羽尖。 </li><li>紧紧围绕圆孔裁剪HDR图像。屏蔽目标外盘金属光圈减小文件大小高达25％。 </li><li>列置换，整组HDR图像中的数据来创建一组文件，一个为每个图像中的多个块组成的，即包含所有的定向反射率值按像素。这些定向反射缓存文件的组织，使快速访问LL的方向在一个单一的像素位置的三维物体的二维投影的颜色测量。 </li></ol></li><li>可视空间变光散射跨层次的规模<ol><li>要浏览测量，使用定制SimpleBrowser应用，解释数据步骤1.E.处理的SimpleBrowser打开的窗口包含由第一事故照明方向照亮的羽毛的形象。 </li><li>在图像上的羽毛叶片，个别像素或一组像素的直链或矩形安排可以被选择（ 图3）。继续通过选择进行分析的羽毛叶片的一个矩形区域。然后，绘制选定区域的平均方向散射光。 A地块窗口显示反射方向余弦函数打开相邻的图像窗口（ 图4中的R1）。 </li><li>默认情况下，该方向的最大亮度（透射方向，在一个TY羽PICAL测量）被分配为1的曝光。减少或增加曝光在一个半停止（√2×）的增量来调整曝光的反射率彩色地图。 </li><li>周期的反射率之间的亮度，RGB和色度的色彩映射（参见图4中的R1，R2和R3）。对于以下步骤使用RGB。 </li><li>要旋转的球体，点击它，使轨迹球接口。拖动界面，引起旋转。要查看反射半球，球返回到它的默认位置（见R2在图4）。球体旋转180°，从它的默认位置，以查看透过率半球（参见图4中的T2）。 </li><li>对于数据的另一种观点认为，选择极性的情节模式，缩放的半径，每个方向上的单位球体由各自的亮度值。改变它的颜色的亮度的地图缩放球体从RGB色度（见P3，F3，S3中，在图4中的A3 </strONG&gt;）。 </li><li>所显示的图像的照明方向的红色圈中的方向的散射图（ 图4）。点击任何其他事故照明方向的羽毛从那个方向照射显示图像。 </li><li>减少或增加曝光的图像，揭示过度和曝光不足的区域。 </li><li>调查反射跨尺度的层次，恢复的情节模式的单位球体和RGB彩色地图。在审查中，该地块从所选图像的矩形区域显示平均定向反射。 </li><li>改变矩形线性的（ 图3）的选择类型。这将允许在矩形区域中的方向反射从个体精细尺度结构的研究。 </li><li>绘制的反射率的线性平均在新窗口中，同时保持矩形平均作参考。调整曝光和一套彩色地图RGB。 </li><l&gt;在的 ​​线性平均容积，小羽枝所跨越的线 ​​性区域的前端能够被看见，以反射光在水平方向（ 图8）。选择一个线性的情节，在左边显示图像中的高反射小羽枝远端的照明方向。 </li><li>步骤朝羽毛的尖端的线，直到它到达该区域的羽毛小羽枝近端分支从相邻支。的线性平均容积的基小羽枝看到的反射光的方向垂直（ 图8）。选择的方向之一，显示在左侧图像中的高反射率的小羽枝近端。 </li><li>在此线性图，观察精细尺度的结构相结合，产生的远场的信号的矩形图中看到的水平和垂直方向的反射光。 </li></ol></li></ol> 2。测量散射光多摄像机方向（中学日常在图1中） 多个相机的看法和非均匀定向抽样，让我们​​来研究特定方向反射的功能。 2.A和2.B校准步骤此外，协议已扩大到处理多个相机视图。 2.C和2.D步骤设置了两个具体的例子生动地说明图1中为次要套路A和二II.B。在这种情况下，摄像机的方向改变从它的规范方向（垂直于表面），这意味着在被拍摄对象从它的表面的法线倾斜的方向。由于图像必须被映射到同一个坐标系，我们整顿和引用闪光灯拍摄目标周围的样品（ 图9），每张照片变形，以符合规范的方向。 <ol class="ualpha"><li>校准相机投影位置: 这些步骤的目的是计算相机PROJ挠度和用于图像变换位置。 <ol><li>剪辑一个方格图案校准目标单位对安装板。 </li><li>规范摄像机视图（ 即{θ，φ} = {0,0}）和一些其他各种相机视图图像传播规范的观点集中在超过120°锥捕捉一幅图像。 </li><li>将图像转换成一个MATLAB工具箱B，摄像机标定工具箱Bouguet。提取每个图像的网格角来重构相机矩阵。出口的内在相机的投影矩阵（P）和外在的摄像头位置基质（M）。的特性相机投影的焦距，主点组成的。外在相机位置主要是由翻译翻译世界的起源到相机的位置。 </li><li>解决的矩阵，该矩阵变换校正目标坐标龙门转台坐标（X）， 即 BougueT空间龙门空间。 </li><li>从金属板打开手机检查模式。 </li></ol></li><li>校准目标位置和投影偏移: 这些步骤的目的是要计算的校准平面，目标平面，和样品之间的偏移量，来定位目标位置。 <ol><li>旋转台架的照相机的光轴垂直于表面平面坐标， 即规范的帧。 </li><li>环周围的光圈与闪光照明的目标的捕获图像。这是典型的图像进行图像对齐。 </li><li>处理原始相机输出（协议中列出的步骤1.E.3.a.和1.E.4。）。 </li><li>掩盖了区域内外环目标区域，消除杂散镜面高光，可能会混淆目标识别，然后找到图像中的目标。 </li><li>放牧角度旋转相机拍摄图像。 </li><li>计算规范的CAMERA姿势（MC = M * RC）和掠射角相机的姿势（镁= M * RG）的基础上的外在相机矩阵M在步骤2.A.3。其中包括Bouguet方格图案的位置的基础上翻译。 </li><li>重新定义M由抵销其翻译的纸靶环的厚度。迭代，直到在龙门Bouguet棋盘和目标， 即厚度的纸靶环的环平面的平面之间的空间偏移，已经通过试验和错误（重新计算通过不同的偏移量校准平面）解决了。验证在每次迭代重新投影的目标的目标在掠射角图像到规范的图像偏移。 </li><li>按照上一步骤中的步骤，重新投影到有孔的，在典型的图像的对象，通过试验和错误，直到有孔的对象中的擦地角图像目标的环的平面的平面的台架之间的空间中的偏移量，重新定义中号f的带孔的对象， 即在金属板的厚度，已经解决了。 </li></ol></li><li>非均匀采样测量七反射半球（ 图1中的辅助日常II.A） <ol><li>检查从相机视图的表面的法线测量的反射光的方向分布， 即{θ，φ} = {0,0}中所描述的协议1。重新取样半球反射，记录相机光芒从非镜面方向更稀疏和镜面方向更密集。 </li><li>应用同样的标准采样6附加数码相机的方向均匀地分布在半半球反射率， 即{θ，φ} = {30,0}，{30,90}，{60,0}，{60,45} ，{60,90}，{60,135}。预测的6个附加试验的镜面区域，从观察方向每个加上初次运行的反射角。 </li><li>对于每一个7的非均匀LY采样半球，采集和处理测量中的指示步骤1.D.，和1.E.所示。 </li><li>视觉化浏览来自同一区域的羽毛在各7非均匀采样的半球方向反射后，在步骤1.F.中的指示所示。排列方向的反射率曲线为每个方向上的极坐标系统，摄像机的方向（看的视觉结果在图1中的常规II篇A， 图5）是基于每个小区的位置7的摄像头。 </li></ol></li><li>测量精细采样半圆形的路径来获得颜色变化的详细信息角（次要日常II.B 如图1） <ol><li>启动SimpleBrowser的应用程序和输入处理后测量的反射率的非均匀采样的半球摄像机的方向{θ，φ} = {0,0}中所描述的步骤2.C.1。上选择ë键图像中的像素，那么适合的平面在所选择的像素位置的亮度的半球反射率的第90百分位。 </li><li>构建一维采集运行，精细样品镜面反射镜面。生成½°的半锥角为单​​位递增，在先前步骤中定义的平面的台架臂的角度。开始的半锥角等于0°增大到90°的半锥角。如果在采集运行中的每一个测量，保持常量并等于对于表面法线的半矢量，以便在镜面反射方向上位于每个摄像机的方向。 </li><li>按照指示在步骤1.D.，采集和处理测量和1.E.所示。 </li><li>视觉化浏览1D方向反射，按照指示步骤1.F.，一边品尝使用相同的像素，以适应在步骤2.D.1镜面上一个很小的区域（ 如 3×3个像素）为中心的。峰值反射率， 即找到方向遮阳正常。构建3个额外的数据获取中相同的方式作为步骤2.D.2中。运行，但设置半遮光，而不是正常的表面法线的向量。三个额外的运行，生成在于飞机含有遮光正常的，但旋转45°，90°和135°的相对于镜面平面，定义在步骤2.D.1的龙门臂角度。 </li><li>按照指示在步骤1.D.，采集和处理测量和1.E.所示。 </li><li>视觉化浏览1D方向反射，按照指示步骤1.F.，同时采样一个非常小的区域（ 例如 3x3的像素）的像素集中使用，以适应在步骤2.D.1镜面。出口从SimpleBrowser的平均反射辐射这个非常小的区域。 </li><li>在MATLAB中，绘制其色度功能半角色度图（ 图6）。画出它的色相，彩度和亮度的函数的半角度（&lt;强图7）。 </li><li>构建四个1D采集运行在与上述相同的四个平面，但这次配置的光，相机的方向测量的宽度和镜面反射率的衰减。设置一个恒定的10°的光与相机之间的半锥角。生成台架臂的角度在1°的半绕轴线的平面垂直的矢量的增量。开始用半矢量等于-80°到+80°，其中0°等于遮光正常增加的半矢量。请注意，并非所有的相机的方向位于镜面的方向。 </li><li>收购，加工和出口测量中的说明步骤1.D.和1.E.，2.D.6。分别</li><li>在MATLAB中，半矢量和遮光正常之间的角度作为一个功能的色度图上绘制色度。画出其色相，彩度和亮度之间的角度的函数的半矢量和遮光正常的。 </li></ol></lI&gt; </ol> 3。射影变换投影变换到典型视图或视线方向正交的平面的面的每一个HDR图像。此协议访问的步骤1.E.3.b测量运行时，存在多个摄像机的方向上设置，如协议2中概述的实施例，并以图形方式示出作为图1中的辅助例程的一部分。 <ol class="ualpha"><li>阅读一个规范的图像从非镜面的方向照射。 （在放牧镜面的方向在纸张表面之间的白色和黑色墨的对比度降低可导致到目标检测故障。比较清晰的图像A和B在图9。） </li><li>找到规范的图像中的每个目标的中心坐标。 </li><li>负载对于一个给定的方向对电灯相机（ 图9中的B）的安装在相机上的闪光照亮的对象图像。 </li><li>大约TRA在目标图像规范画幅相机使用龙门相机矩阵M计算的步骤2.B.7 nsform。 </li><li>找到每个目标的中心的坐标变换后的目标图像（ 图9中的C）。 </li><li>在变换后的目标图像，其通过寻找参考图像和目标之间的最小距离，在典型的图像的参照目标的每个目标相匹配。 </li><li>丢弃任何目标模糊所造成的自由度在掠射角（ 图9中的D）。 </li><li>解决了二维射影变换，映射图像目标的规范框架规范在同一帧图像目标。 </li><li> Untransform的翘曲以适合从规范的图像帧的目标返回到原始图像帧通过的平面有孔的对象（M在步骤2.B.8），而不是平面（M在第2步中的目标。 B.7）。 </li><li>减的目标范围内的孔的有孔观察目标图像中的对象的坐标对在规范的目标图像的拍摄对象。 </li><li>加载HDR图像照明灯（ 图9）。 </li><li>推断出空间射影变换从得救目标坐标对HDR图像转换成规范的框架（ 图9中的E）。 </li><li>返回到主协议。 </li></ol> 一个 Dcraw执行是由大卫棺材开发的一个开源的计算机程序。相机的专有的RAW格式图像（ 即未处理CCD数据）转换成一个标准的图像格式。见<a href="http://www.cybercom.net/~dcoffin/dcraw/" target="_blank">http://www.cybercom.net/〜dcoffin / / dcraw的</a> 。 b Bouguet工具箱的相机标定工具箱的MATLAB开发让伊夫Bouguet的。见" <a href="http://www.vision.caltech.edu/bouguetj/calib_doc" target="_blank">http://www.vision.caltech.edu/bouguetj/calib_doc" 。</a>

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没有利益冲突的声明。

虽然是公认的许多色素和结构性着色的性能和功能，许多珠被形态是如此复杂，其结构细节和功能知之甚少。珠被开发的专业空间变化的有机体的表面差异定向反射光朝向观察者。方向性受到了关注，主要由于其颜色转变变化事件和视角，研究生物包膜的彩虹，彩虹色的研究已经获得了主要的一维和二维测量8,12,17。但广义6D测量尚未完成例程珠被,21-23，闪光或其他在这个研究中，我们的方法提供了不同方向的颜色数据的缺乏而受到限制和对有机体的颜色表型的文献。 是优选的R的羽毛ICH外皮材料，包括安排毫尺度结构的倒刺:支，小羽枝远端和近端小羽枝。的元素和它们的复杂安排的规模小，使其难以辨别的光散射性能的各个元素。我们的协议，成功地分离出毫规模结构，从宏观尺度的几何形状的影响。通过定向表达毫规模结构远场签名的羽毛表征功能的后果，我们启用了调查，他们的适应性后果。 我们面临的实际光谱，空间和角度分辨率之间的权衡。我们选择高空间，为我们的研究中角度和低光谱。其他组合可以使用，但一些（ 例如，所有高）导致测量时间unworkably长。其中重要的是正在研究的特定现象，必须集中注意。在选择聘请RGB CA，照相机与拜耳滤波器马赛克，我们设计了我们的协议，以与人类视觉系统相匹配。 RGB摄像头可以被替换，和我们的协议适合于测量的相对色刺激值的任何生物体， 例如在紫外光谱的灵敏度测量幕四有彩色24,25。光谱成像相机将提供最通用的解决方案25。 我们展示了我们的协议与三级飞羽翅膀上的羽毛，因为他们是丰富多彩的，容易对参考板扁平。不幸的是，在金属板的孔径，发现只有一小部分的羽毛表面。如果我们能同时测量三维形状的羽毛表面，同时测量其反射率25，我们能避免机械压平的羽毛，而在它的自然，不平的状态测量整个羽毛。 互动化，专业化，集成的数据可视化工具提供substanti人有利于科学家探索和解释大数据量。的集成和交互性越大，越容易观察到在数据连接。在我们的软件，用户可以交互地绘制平均定向散射面位置（ 图4）为一个函数。进一步发展我们的软件可以集成其他的绘图功能（ 图6，图7），以扩大的交互式体验。

生物体的体壁的颜色和图案发挥生态和社会批判功能在大多数动物类群。这些表型特性是由体壁的结构，它可以表现出光散射变化空间 （穿过体壁的表面）和定向 （带照明和观察方向的变动）与光相互作用。在复杂的生物材料，如羽毛的光的散射方向的方向重复毫寸几何形状的影响。毫的尺度结构本身可被嵌入具有纳米尺度的结构，如黑色素阵列，这往往继承毫尺度方向。从纳米到宏观尺度，体壁的结构，已经演变功能，以增加信号的能力的有机体。为了评估不同尺度下的形态的影响后的整体外观，工具测量和分析生物结构的颜色，需要灵活定向光散射隔离各种比例倍率。 我们开发了基于图像的测量工具，羽毛的复杂和多变的毫尺度形态学（倒钩支，小羽枝远端和近端的小羽枝）的性能，研究如何扩大表达的范围可以从单独的纳米尺度结构。在一个单一的照相机所记录的图像中，我们观察到的反射光的羽毛的表面上在不同的位置不同，也就是光的反射率是空间上变化的。当我们搬到相对于羽毛的光，摄像机的方向，我们观察到的反射率变化，也就是光的反射率定向变1。根据这些意见，我们设计了一个协议，有条不紊地移动相机拍摄目标周围的光线和采用球形龙门2,3，而我们抓获2尺寸苏rface位置（X和Y），2维的光的方向 （纬度和经度），和2个摄像机的方向 （纬度和经度）的尺寸（ 图2）。在软件中，我们直观地探讨了6个维度作为一个功能的位置，光照方向和视图方向的散射光。 以前的研究成珠被反射的太频繁贴现方向性的贡献- 如漫反射与镜面或各向同性与各向异性反射-色彩表现。大多数有固定的颜色测量入射光，对象和观赏几何小心避免方向性的影响。比如，从颜色测量以消除镜面反射，它是常见的，将垂直于表面的光，并记录从正常的45°处的反射率。定向不同的反射率做链接的形态的研究通常集中在纳米尺度虹彩后果4-8。很少有人考虑远场光学签名8-11微，毫，宏观尺度几何的贡献。因此，通常使用的光检测器，对总反射率，通过单一的感兴趣区域可以包括多个毫和/或宏观尺度的组件，如倒刺支，小羽枝，甚至整个羽毛6,8,11-17 。当感兴趣的区域是小于分辨极限的检测器或检测器的视场的形状不符合时，常用的协议指定从特定的毫寸元素的8,10剥离试料的光散射隔离，13,15。 我们已经开发了一个更具包容性的协议，鼓励探索的许多其他更有针对性的研究中常常被忽略的变量的测量采集和可视化。我们测量散射光在球体的方向和ACROS一个地区的空间，使用一个巨大的高动态范围，高清晰度的照片取自一套有系统的光线和观察方向。我们采用了高分辨率成像传感器，二维数组的判罚尺度像素探测器。聚集在硬件发生在像素级，在规模较小的比毫规模的元素，我们测量。个别的第二级聚集体在软件中的像素作为用户选择的感兴趣的区域的形状和大小。因此，单次测量集可以反复分析软件与多种生物相关的位置和尺度材料在不同方面去探索光的相互作用。通过消除夹层和测量整个羽毛，我们的协议的优点是离开的羽毛叶片的形态完好，保留自然的上下文和功能之间构成毫规模元件的光的相互作用。 光散射从的organismal structure是多方面的，难以量化的。光散射测量6D不能还可以归因于特定的形态奇异的仪器与任何规模的层次内。但在这样的追求中，我们已经迈出了重要步伐。我们已经开发出一种工具，其中包括三个互补的方法 - 使用龙门采样反射率，探索大数据量的软件，图形化和可视化的数据子集 - 来扩展我们的能力来衡量6D光散射材料上的任何点，下降到毫规模。像我们这样的协议，我们预计的生物学家将识别无数定向和空间变化的特征和相应的适应发展的多尺度结构。使用我们的工具，我们正在从事表征信号毫尺度结构的方向和空间表达的潜力，希望揭示其自适应后果。我们解决一系列的问题，如:从Y坐标的观测点，判罚尺度元素或总规模的地区反映强烈的羽毛？如何判罚尺度元素的方向影响的散射光的方向吗？什么形态的条件产生滑腻亮片闪耀的光泽与五彩斑斓的装饰品吗？做一些物种产生更广泛的"窗口"观察虹彩比别人吗？这些问题可能​​会被要求对鸟类和它们的每一片羽毛，但也对任何其他生物信号，伪装，或其他原因已经进化出了特殊的表面外观。

measuring spatially- and directionally-varying light scattering from biological material

光与空间尺度上的各种生物体的体壁。例如，在闪光的小鸟:纳米尺度结构产生的颜色;倒钩和小羽枝毫尺度结构在很大程度上决定了方向性的图案的反射光，并通过宏观尺度空间结构重叠，弯曲的羽毛，这些方向性的影响创造视觉质感。毫尺度和宏观尺度的影响，决定于生物体的身体，和什么样的观点和在什么照明，看到斑斓色彩。因此，高度定向虹彩喉蜂鸟绚丽的色彩，闪光不足来解释其纳米尺度的结构和问题依然存在。从一个给定的观察点，毫规模的羽毛元素为导向，以反映强烈？做一些物种产生更广泛的"窗口"观察虹彩比别人吗？这些以及类似的问题米唉被问及任何生物体进化出了特殊的表面外观，信号，伪装，或其他原因。 为了研究方向的光散射模式从羽毛，鸟的毫规模形态的关系，我们开发了一个协议，从生物材料，使用许多高清晰度拍摄的照片与不同的照明和观察方向的散射光测量。由于我们测量散射光方向的函数，我们可以观察到从特定的羽毛散射光的方向分布的特征，因为在我们的影像解决倒钩和小羽枝，我们可以很清楚这些不同属性的定向功能微小尺度的结构。保存完好的标本保留总规模分散行为在自然界中见到。这里描述的方法提出了一种用于分析空间和定向va的广义的协议rying从复杂的生物材料的光散射在多个结构尺度。

我们的协议的主要测量（常规I的图1）固定摄像机的方向垂直于表面，只移动的光。由于光散射坚持互惠的原则，其结果是相同的，无论我们握住相机不变，而移动的光在半球或反之亦然。当我们固定相机或光线不足，完整的4维方向集。观察时，主要的测量不一样，既轻又相机移动相差的表面法线方向多重散射行为甲更全面的了解。理想的情况下，我们可以从许多相机的方向测量的光散射，甚至多达入射光的方向的数量，以产生一个对称的数据集。在实践中，这将需要有太多的暴露。在我们的经验中，我们可以得到足够的信息不同的观看位置，通过移动相机，几十倍地设想明180度旋转对称的表面正常。在的二次测量阶段，我们从7个观察方向分布在半球ZENITH 18,19（常规II.A 如图1）60°的范围内获得的测量数据。 我们在本文的数字，显示出有代表性的数据测量，这是彩虹色，有光泽，和各向异性反射（ 图5）Lamprotornis 曲霉 （紫色光泽椋鸟）的羽毛。在每个观察方向（7），收集反射光的从数百个半球上的入射照明方向。的方向形成一个窄带正交取向的羽毛的中心轴线（在图4中看到，羽绒图像）。斑斓的颜色转变是微妙的（在正常发病率的蓝绿色和蓝绿色放牧发病）的羽毛时，被认为是正常的在其表面看到{0°，0和de克;} RGB图如图5所示 。的视野角的方法放牧，观察方向和掠入射方向之间的角度最大化，导致更醒目的颜色偏移（蓝绿色事件和观看方向之间，在240℃，在0℃和品红色）看出，在{60°，0°} RGB 图5中的情节。 我们可以买得起步骤的灯光和摄像机，当我们在更精细的角分辨率限制的动作一维图6显示了色度的反射L.之间的角度的函数的入射和观察方向，入射和观察方向的平面中包含镜面反射的波段，该波段的纵向轴线垂直于前端barbule 曲霉羽。由于彩虹色弧通过色度空间，色调的变化从蓝绿色到紫色。 空间变<html>方向反射的振动性是可见的，不同的（X，Y）坐标的体壁对应不同的毫规模结构。在的情况下，L。麴只有一个结构-远端barbule的-可见在大部分的面积。与此相反，在C cupreus，三个毫尺度结构-支，前端小羽枝和小羽枝近端-明确区分数据中，我们可以观察到反射率的羽毛的方向相对于每个结构的纵向轴线（ 图8） 。 <img alt="图1" fo:content-width="5in" fo:src="/files/ftp_upload/50254/50254fig1highres.jpg" src="/files/ftp_upload/50254/50254fig1.jpg" /> 图1。这示意性概览描绘了两种安装方法，球形台架坐标系统，采集采样的类型和它们各自的结果。<html> / ftp_upload/50254/50254fig1large.jpg"目标="_blank"&gt;点击这里查看大图。 <img alt="图2" src="/files/ftp_upload/50254/50254fig2.jpg" /> 图2。扁平的羽毛是可见的通过孔径的金属板包围的一环目标构成的球形龙门可以测量光散射从多个事故照明和观察方向羽毛。 L =光臂（纬度）。 C =相机臂（纬度）。 B =相机底座（经度）。 T =转盘（经度）。 F =羽毛。 <img alt="图3" src="/files/ftp_upload/50254/50254fig3.jpg" /> 图3。平均方向散射，可以计算从羽毛叶片点，线或矩形区域。 p_upload/50254/50254fig4highres.jpg"SRC ="/ files/ftp_upload/50254/50254fig4.jpg"/&gt; 图4。例如定向散射绘图功能（R * =反射，T * =透光率，P * =亮度= F * =前，S * =侧，A * =任意）和颜色方案（* 1，* 2 = RGB * 3 =色度） <a href="https://www.jove.com/files/ftp_upload/50254/50254fig4large.jpg" target="_blank">点击此处查看大图</a> 。 <img alt="图5" fo:content-width="4.5in" fo:src="/files/ftp_upload/50254/50254fig5highres.jpg" src="/files/ftp_upload/50254/50254fig5.jpg" /> 图5。的亮度（顶部）和RGB色彩（底部）的半球形（仰角，方位角）坐标对从观察方向余弦空间中的反射率:{0°，0°}，{30°，0°}，{ 30°，90°}，{60°，0°}，{60°，45°}，{60°，90°}和{60°，135°}的反射率<html>从一个25×25像素的矩形区域的横向叶片的三级飞羽L.的平均值曲霉 （紫色光泽椋鸟）的羽毛。红色箭头代表相机的方向。 <a href="https://www.jove.com/files/ftp_upload/50254/50254fig5large.jpg" target="_blank">点击这里查看大图</a> 。 <img alt="图6" fo:content-width="6in" fo:src="/files/ftp_upload/50254/50254fig6highres.jpg" src="/files/ftp_upload/50254/50254fig6.jpg" /> 图6。色度半角的函数，事件之间的放大区域的亮度和观看方向:CIE 1976色度均匀秤（USC）的反射率。 <a href="https://www.jove.com/files/ftp_upload/50254/50254fig6large.jpg" target="_blank">点击这里查看大图</a> 。 / 50254/50254fig7highres.jpg的"SRC ="/ files/ftp_upload/50254/50254fig7.jpg"/&gt; 图7。入射照明和观看方向之间的角度的函数的反射率，在平面（红色）和垂直于（阴影部分）的纵向轴线的的前端barbule:（A）（B）的百分比色度，主波长，（C ）百分比的亮度。情节的颜色底纹为RGB颜色的反射率。负波长值代表在非光谱的紫色三角形的颜色。 <a href="https://www.jove.com/files/ftp_upload/50254/50254fig7large.jpg" target="_blank">点击这里查看大图</a> 。 <img alt="图8" fo:content-width="5in" fo:src="/files/ftp_upload/50254/50254fig8highres.jpg" src="/files/ftp_upload/50254/50254fig8.jpg" /> 图8。 C.两个相邻支远端的小羽枝和近端小羽枝平均定向反射cupreus（AF菜翡翠布谷鸟）。 <img alt="图9" fo:content-width="6in" fo:src="/files/ftp_upload/50254/50254fig9highres.jpg" src="/files/ftp_upload/50254/50254fig9.jpg" /> 图9所示。 （C）（A）非整流龙门灯亮起的图像，（B）非整流图像，相机闪光灯照亮，筛选目标候选人仿射变换，闪光照明图像（D）可接受尖锐的深度范围内的目标场，（E）整流灯照的图像，（F）旋转的羽毛尖，裁剪和屏蔽。 <a href="https://www.jove.com/files/ftp_upload/50254/50254fig9large.jpg" target="_blank">点击这里查看大图</a> 。

Watch this Scientific Journal Video about Measuring Spatially- and Directionally-varying Light Scattering from Biological Material at JoVE.com

Measuring Spatially- and Directionally-varying Light Scattering from Biological Material

我们提出了一种非破坏性的采样空间变化方向的散射光从结构复合材料的方法。通过保持材料的完整，我们保留总规模散射行为，同时捕捉高分辨率成像的判罚尺度定向捐款。结果可视化软件，生物相关的位置和规模。

从生物材料空间定向变化的光散射测量

Light interacts with an organism's integument on a variety of spatial scales. For example in an iridescent bird: nano-scale structures produce color; the ...

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12.5K 次观看.  Cornell University. 我们提出了一种非破坏性的采样空间变化方向的散射光从结构复合材料的方法。通过保持材料的完整，我们保留总规模散射行为，同时捕捉高分辨率成像的判罚尺度定向捐款。结果可视化软件，生物相关的位置和规模。

视频: Measuring Spatially- and Directionally-varying Light Scattering from Biological Material

Fabrication of Spatially Confined Complex Oxides

Complex materials such as high Tc superconductors, multiferroics, and colossal magnetoresistors have electronic and magnetic properties that arise from the inherent strong electron correlations that reside within them. These materials can also possess electronic phase separation in which regions of vastly different resistive and magnetic behavior can coexist within a single crystal alloy material. By reducing the scale of these materials to length scales at and below the inherent size of the electronic domains, novel behaviors can be exposed. Because of this and the fact that spin-charge-lattice-orbital order parameters each involve correlation lengths, spatially reducing these materials for transport measurements is a critical step in understanding the fundamental physics that drives complex behaviors. These materials also offer great potential to become the next generation of electronic devices 1-3. Thus, the fabrication of low dimensional nano- or micro-structures is extremely important to achieve new functionality. This involves multiple controllable processes from high quality thin film growth to accurate electronic property characterization. Here, we present fabrication protocols of high quality microstructures for complex oxide manganite devices. Detailed descriptions and required equipment of thin film growth, photo-lithography, and wire-bonding are presented.

We describe the use of pulsed laser deposition (PLD), photolithography and wire-bonding techniques to create micrometer scale complex oxides devices. The PLD is utilized to grow epitaxial thin films. Photolithography and wire-bonding techniques are introduced to create practical devices for measurement purposes.

空间密闭的复合氧化物制备

Complex materials such as high Tc superconductors, multiferroics, and colossal magnetoresistors have electronic and magnetic properties that arise from ...

科研

工程学

Measuring Material Microstructure Under Flow Using 1-2 Plane Flow-Small Angle Neutron Scattering

A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is presented. The SANS shear cell consists of a concentric cylinder Couette geometry that is sealed and rotating about a horizontal axis so that the vorticity direction of the flow field is aligned with the neutron beam enabling scattering from the 1-2 plane of shear (velocity-velocity gradient, respectively). This approach is an advance over previous shear cell sample environments as there is a strong coupling between the bulk rheology and microstructural features in the 1-2 plane of shear. Flow-instabilities, such as shear banding, can also be studied by spatially resolved measurements. This is accomplished in this sample environment by using a narrow aperture for the neutron beam and scanning along the velocity gradient direction. Time resolved experiments, such as flow start-ups and large amplitude oscillatory shear flow are also possible by synchronization of the shear motion and time-resolved detection of scattered neutrons. Representative results using the methods outlined here demonstrate the useful nature of spatial resolution for measuring the microstructure of a wormlike micelle solution that exhibits shear banding, a phenomenon that can only be investigated by resolving the structure along the velocity gradient direction. Finally, potential improvements to the current design are discussed along with suggestions for supplementary experiments as motivation for future experiments on a broad range of complex fluids in a variety of shear motions.

A shear cell is developed for small-angle neutron scattering measurements in the velocity-velocity gradient plane of shear and is used to characterize complex fluids. Spatially resolved measurements in the velocity gradient direction are possible for studying shear-banding materials. Applications include investigations of colloidal dispersions, polymer solutions, and self-assembled structures.

测量材料在微流使用1-2面流小角中子散射

A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is ...

Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials

The spin echo resolved grazing incidence scattering (SERGIS) technique has been used to probe the length-scales associated with irregularly shaped crystallites. Neutrons are passed through two well defined regions of magnetic field; one before and one after the sample. The two magnetic field regions have opposite polarity and are tuned such that neutrons travelling through both regions, without being perturbed, will undergo the same number of precessions in opposing directions. In this case the neutron precession in the second arm is said to &#34;echo&#34; the first, and the original polarization of the beam is preserved. If the neutron interacts with a sample and scatters elastically the path through the second arm is not the same as the first and the original polarization is not recovered. Depolarization of the neutron beam is a highly sensitive probe at very small angles (&#60;50&#160;&#956;rad) but still allows a high intensity, divergent beam to be used. The decrease in polarization of the beam reflected from the sample as compared to that from the reference sample can be directly related to structure within the sample.
In comparison to scattering observed in neutron reflection measurements the SERGIS signals are often weak and are unlikely to be observed if the in-plane structures within the sample under investigation are dilute, disordered, small in size and polydisperse or the neutron scattering contrast is low. Therefore, good results will most likely be obtained using the SERGIS technique if the sample being measured consist of thin films on a flat substrate and contain scattering features that contains a high density of moderately sized features (30 nm to 5 &#181;m) which scatter neutrons strongly or the features are arranged on a lattice. An advantage of the SERGIS technique is that it can probe structures in the plane of the sample.

Progress has been made in utilizing spin echo resolved grazing incidence scattering (SERGIS) as a neutron scattering technique to probe the length-scales in irregular samples. Crystallites of [6,6]-phenyl-C61-butyric acid methyl ester have been probed using the SERGIS technique and the results confirmed by optical and atomic force microscopy.

使用中子自旋回声解决放牧发生率散射调查有机太阳能电池材料

The spin echo resolved grazing incidence scattering (SERGIS) technique has been used to probe the length-scales associated with irregularly shaped ...

Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle

Plasmonics, which are based on the collective oscillation of electrons due to light excitation, involve strongly enhanced local electric fields and thus have potential applications in nonlinear optics, which requires extraordinary optical intensity. One of the most studied nonlinearities in plasmonics is nonlinear absorption, including saturation and reverse saturation behaviors. Although scattering and absorption in nanoparticles are closely correlated by the Mie theory, there has been no report of nonlinearities in plasmonic scattering until very recently. 
Last year, not only saturation, but also reverse saturation of scattering in an isolated plasmonic particle was demonstrated for the first time. The results showed that saturable scattering exhibits clear wavelength dependence, which seems to be directly linked to the localized surface plasmon resonance (LSPR). Combined with the intensity-dependent measurements, the results suggest the possibility of a common mechanism underlying the nonlinear behaviors of scattering and absorption. These nonlinearities of scattering from a single gold nanosphere (GNS) are widely applicable, including in super-resolution microscopy and optical switches. 
In this paper, it is described in detail how to measure nonlinearity of scattering in a single GNP and how to employ the super-resolution technique to enhance the optical imaging resolution based on saturable scattering. This discovery features the first super-resolution microscopy based on nonlinear scattering, which is a novel non-bleaching contrast method that can achieve a resolution as low as l/8 and will potentially be useful in biomedicine and material studies.

Saturable and reverse saturable scattering were discovered in isolated plasmonic particles and adopted as a novel non-bleaching contrast method in super-resolution microscopy. Here the experimental procedures of detecting and extracting nonlinear scattering are explained in detail, as well as how to enhance resolution with the aid of saturated excitation microscopy.

从单电浆纳米粒子散射非线性测量

Plasmonics, which are based on the collective oscillation of electrons due to light excitation, involve strongly enhanced local electric fields and thus ...

Experimental Methods for Investigation of Shape Memory Based Elastocaloric Cooling Processes and Model Validation

Shape Memory Alloys (SMA) using elastocaloric cooling processes have the potential to be an environmentally friendly alternative to the conventional vapor compression based cooling process. Nickel-Titanium (Ni-Ti) based alloy systems, especially, show large elastocaloric effects. Furthermore, exhibit large latent heats which is a necessary material property for the development of an efficient solid-state based cooling process. A scientific test rig has been designed to investigate these processes and the elastocaloric effects in SMAs. The realized test rig enables independent control of an SMA&#39;s mechanical loading and unloading cycles, as well as conductive heat transfer between SMA cooling elements and a heat source/sink. The test rig is equipped with a comprehensive monitoring system capable of synchronized measurements of mechanical and thermal parameters. In addition to determining the process-dependent mechanical work, the system also enables measurement of thermal caloric aspects of the elastocaloric cooling effect through use of a high-performance infrared camera. This combination is of particular interest, because it allows illustrations of localization and rate effects &#8212; both important for efficient heat transfer from the medium to be cooled.
The work presented describes an experimental method to identify elastocaloric material properties in different materials and sample geometries. Furthermore, the test rig is used to investigate different cooling process variations. The introduced analysis methods enable a differentiated consideration of material, process and related boundary condition influences on the process efficiency. The comparison of the experimental data with the simulation results (of a thermomechanically coupled finite element model) allows for better understanding of the underlying physics of the elastocaloric effect. In addition, the experimental results, as well as the findings based on the simulation results, are used to improve the material properties.

Experimental methods for investigation of solid state cooling processes and characterization of elastocaloric material properties of Shape Memory Alloys (SMA) are presented. A custom-built test rig has been designed for controlling and comprehensive monitoring of elastocaloric cooling processes. Furthermore, it provides a validation platform for thermomechanically coupled modeling approaches.

基于形状记忆调查Elastocaloric冷却过程和模型验证实验方法

Shape Memory Alloys (SMA) using elastocaloric cooling processes have the potential to be an environmentally friendly alternative to the conventional vapor ...

Scanning Light Scattering Profiler (SLPS) Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light scattering from intraocular lenses (IOLs) using goniophotometer principles. This protocol describes the SLSP platform and how it employs a 360&#176; rotational photodetector sensor that is scanned around an IOL sample while recording the intensity and location of scattered light as it passes through the IOL medium. The SLSP platform can be used to predict, non-clinically, the propensity for current and novel IOL designs and materials to induce light scatter. Non-clinical evaluation of light scattering properties of IOLs can significantly reduce the number of patient complaints related to unwanted glare, glistening, optical defects, poor image quality, and other phenomena associated with the unintended light scattering. Future studies should be conducted to correlate SLSP data with clinical results to help identify which measured light scatter is most problematic for patients that have undergone cataract surgery subsequent to IOL implantation.

Scanning Light Scattering Profiler SLPS Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

This protocol describes the scanning light scattering profiler (SLSP) that enables the full-angle quantitative evaluation of forward and backward scattering of light from intraocular lenses (IOLs) using goniophotometer principles.

基于扫描光散射分析器（SLPS）的方法来量化评估来自眼内镜的前向和后向光散射

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light ...

High-speed Continuous-wave Stimulated Brillouin Scattering Spectrometer for Material Analysis

Recent years have witnessed a significant increase in the use of spontaneous Brillouin spectrometers for non-contact analysis of soft matter, such as aqueous solutions and biomaterials, with fast acquisition times. Here, we discuss the assembly and operation of a Brillouin spectrometer that uses stimulated Brillouin scattering (SBS) to measure stimulated Brillouin gain (SBG) spectra of water and lipid emulsion-based tissue-like samples in transmission mode with &lt;10 MHz spectral-resolution and &lt;35 MHz Brillouin-shift measurement precision at &lt;100 ms. The spectrometer consists of two nearly counter-propagating continuous-wave (CW) narrow-linewidth lasers at 780 nm whose frequency detuning is scanned through the material Brillouin shift. By using an ultra-narrowband hot rubidium-85 vapor notch filter and a phase-sensitive detector, the signal-to-noise-ratio of the SBG signal is significantly enhanced compared to that obtained with existing CW-SBS spectrometers. This improvement enables measurement of SBG spectra with up to 100-fold faster acquisition times, thereby facilitating high spectral-resolution and high-precision Brillouin analysis of soft materials at high speed.

We describe the construction of a rapid continuous-wave-stimulated-Brillouin-scattering (CW-SBS) spectrometer. The spectrometer employs single-frequency diode-lasers and an atomic vapor notch-filter to acquire transmission spectra of turbid/non-turbid samples with high spectral-resolution at speeds up to 100-fold faster than those of existing CW-SBS spectrometers. This improvement enables high-speed Brillouin material analysis.

用于材料分析的高速连续波受激布里渊散射光谱仪

Recent years have witnessed a significant increase in the use of spontaneous Brillouin spectrometers for non-contact analysis of soft matter, such as ...

Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons

We have developed a unique method to measure the excitation and coupling rates between the light emitters and surface plasmon polaritons (SPPs) arising from metallic periodic arrays without involving time-resolved techniques. We have formulated the rates by quantities that can be measured by simple optical measurements. The instrumentation based on angle- and polarization-resolved reflectivity and photoluminescence spectroscopy will be described in detail here. Our approach is intriguing due to its simplicity, which requires routine optics and several mechanical stages, and thus is highly affordable to most of the research laboratories.

This protocol describes the instrumentation for determining the excitation and coupling rates between light emitters and Bloch-like surface plasmon polaritons arising from periodic arrays.

光发射器与表面等离子体极化激元的激发和耦合速率的测定

We have developed a unique method to measure the excitation and coupling rates between the light emitters and surface plasmon polaritons (SPPs) arising ...

Synchrotron X-ray Microdiffraction and Fluorescence Imaging of Mineral and Rock Samples

In this report, we describe a detailed procedure for acquiring and processing&#160;x-ray microfluorescence (&#956;XRF), and Laue and powder microdiffraction two-dimensional (2D) maps at beamline 12.3.2 of the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory. Measurements can be performed on any sample that is less than 10 cm x 10 cm x 5 cm, with a flat exposed surface. The experimental geometry is calibrated using standard materials (elemental standards for XRF, and crystalline samples such as Si, quartz, or Al2O3 for diffraction). Samples are aligned to the focal point of the x-ray microbeam, and raster scans are performed, where each pixel of a map corresponds to one measurement, e.g., one XRF spectrum or one diffraction pattern. The data are then processed using the in-house developed software XMAS, which outputs text files, where each row corresponds to a pixel position. Representative data from moissanite and an olive snail shell are presented to demonstrate data quality, collection, and analysis strategies.

We describe a beamline setup meant to carry out rapid two-dimensional x-ray fluorescence and x-ray microdiffraction mapping of single crystal or powder samples using either Laue (polychromatic radiation) or powder (monochromatic radiation) diffraction. The resulting maps give information about strain, orientation, phase distribution, and plastic deformation.

矿物和岩石样品的同步辐射 x 射线 Microdiffraction 和荧光成像

In this report, we describe a detailed procedure for acquiring and processing&#160;x-ray microfluorescence (&#956;XRF), and Laue and powder ...

Measurement of Dynamic Force Acted on Water Strider Leg Jumping Upward by the PVDF Film Sensor

This study aimed to make an explanation for the phenomenon in nature that water strider usually jumps or glides on the water surface easily but quickly, with its peak locomotion speed reaching 150 cm/s. First of all, we observed the microstructure and hierarchy of water strider legs using the scanning electron microscope. On the basis of the observed morphology of the legs, a theoretical model of the detachment from water surface was established, which explained water striders' capability to slide on water surface effortlessly in terms of energy reduction. Secondly, a dynamic force measurement system was devised using the PVDF film sensor with excellent sensitivity, which could detect the whole interaction process. Subsequently, a single leg in contact with water was pulled upward at different speeds, and the adhesion force was measured at the same time. The results of the departing experiment suggested a deep understanding of the fast jumping of water striders.

The protocol here is dedicated to investigating the free and quick maneuvering of water strider on water surface. The protocol includes observing the microstructure of legs and measuring the adhesion force when departing from water surface at different speeds.

PVDF 薄膜传感器对水黾腿跳起动力的测量

This study aimed to make an explanation for the phenomenon in nature that water strider usually jumps or glides on the water surface easily but quickly, ...