生物光子学502资料.pptVIP

点扩散函数 (point spread function, 简称PSF)。是描述光学系统对点源解析能力的函数。因为点源在经过任何光学系统后都会由于衍射而形成一个扩大的像点。 根据光的衍射理论可以研究点光源至透镜、至像平面光波的整个传播过程，最后得出像平面上强度分布是透镜孔径函数的夫琅和费衍射图样，称为光学系统的强度脉冲响应，或点扩展函数 。由它可以确定光学系统的成像性质，因为任意复杂物体由无数点源组成，其像的强度为物强度与点扩展函数的卷积。 通过测量系统的点扩展函数，利用解卷积方法能够更准确地提取图像信息。 * 一副数字图像可以看作一个二维空间的离散函数可以表示为f(x, y), 假设有对于二维卷积操作函数C(u, v) ，则会产生输出图像g(x, y) = f(x, y) *C(u,v), 利用卷积可以实现对图像模糊处理，边缘检测，产生轧花效果的图像。 反之，通过解卷积可以消除模糊。 * 从显微镜厚样本成像原理知道, 第j 幅切片图像是所有样本平面与相应点扩散函数的卷积之和, 每一个切片图像中都包含有焦平面信息和散焦信息, 人们希望从光学切片中去除或减弱散焦信息, 以去除结构假象, 提高图像的分辨率。 * * * * * * * * FD：视场光阑；AD：孔径光阑 * Diaphragm，光阑，膜片? * * * * * * * * * * * * * Birefringence 双折射 * Columnar柱状的 * * * blowfly，绿头苍蝇；ferro-silicon alloy，硅铁合金；retardation plate?延迟板，减速板；Photomicrograph，显微照片 * * * Excited state lifetime The excited state of a fluorophore is characterized by a very short half-life, usually on the order of a few nanoseconds. During this brief period, the excited molecules generally relax toward the lowest vibrational energy level within the electronic excited state. The energy lost in this relaxation is dissipated as heat. It is from the resulting relaxed singlet excited state (S1) that fluorescence emission originates. Emission When a fluorochrome molecule falls from the excited state to the ground state, light is often emitted at a characteristic wavelength. The energy of the emitted photon (hnEM) is the difference between the energy levels of the two states (Fig 2), and that energy difference determines the wavelength of the emitted light (lEM). lEM = hc/EEM?, where E = the energy difference between the energy levels of the two states during emission (EM) of light; h = Planck’s constant; c = the speed of light A laser-scanning instrument or a CCD-camera can be used to measure the intensity of the fluorescent light and subsequently create a digital image of the sample. Image analysis makes it possible to view, measure, render, and quantify the resulting image. bovine vascular 牛血管内皮细胞 * Nucleus细胞核 Tubulin微管蛋白 Mitochondrial线粒体 Golgi complex