Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, California 92697, USA.
Opt Lett. 2012 Oct 1;37(19):3957-9. doi: 10.1364/OL.37.003957.
Laser speckle imaging (LSI) is a noninvasive optical imaging technique able to provide wide-field two-dimensional maps of moving particles. Raw laser speckle images are typically taken with a scientific-grade monochrome camera. We demonstrate that a digital single-lens reflex (dSLR) camera with a Bayer filter is able to provide similar sensitivity despite taking information only from a specific pixel color. Here we demonstrate the effect of changing three primary dSLR exposure settings (i.e., aperture, exposure time/shutter speed, and gain/sensitivity (ISO)) on speckle contrast. In addition, we present data from an in vivo reactive hyperemia experiment that demonstrates the qualitative similarity in blood-flow dynamics visualized with a color dSLR and a scientific-grade monochrome camera.
激光散斑成像(LSI)是一种非侵入性的光学成像技术,能够提供运动粒子的宽场二维图谱。原始的激光散斑图像通常是用科学级单色相机拍摄的。我们证明,尽管只能从特定的像素颜色获取信息,但具有拜耳滤光片的数码单反相机(dSLR)也能够提供类似的灵敏度。在这里,我们展示了改变三个主要的 dSLR 曝光设置(即光圈、曝光时间/快门速度和增益/灵敏度(ISO))对散斑对比度的影响。此外,我们还展示了一个体内反应性充血实验的数据,该实验表明使用彩色 dSLR 和科学级单色相机可视化血流动力学的定性相似性。