生物光子学5-03.ppt

Marvin Minsky马文·闵斯基，生于1927年8月9日，美国人工智能领域的科学家。MIT人工智能实验室的联合创始人。美国国家工程院和美国国家科学院院士，于1969年获得图灵奖，1990年获得日本奖，2001年获得本杰明·富兰克林奖章。 闵斯基的专利包括第一头式图形显示器（1963年）以及共焦扫描显微镜（今天广泛使用共聚焦激光扫描显微镜的前身），并和西摩尔?派普特一起拥有第一个标志“乌龟”。闵斯基于1951年制造了第一个随机有线神经网络学习机：SNARC。 * * LSCF要实现成像，必须通过2D扫描获得序列数据，然后通过图像重构得到2D图像。 要获得3D信息，还要对z轴做光学切片，这样可重构得到3D图像. * * The main drawback image acquisition is not as rapid as widefield techniques in which the entire image is acquired simultaneously. * A confocal microscope illuminates one region after another until the whole field of view is sampled. In most confocal microscopes the aim is to illuminate with light that is focused to the very smallest spot possible in the plane of focus. This diffraction-limited spot of illumination is created by sending a collimated plane wave into the back of the objective where it is transformed into a converging spherical wave by the lens. Thus the full NA of the lens (Fig. 1a) is used to focus the light sharply at a single point at the so-called ‘waist’ of an hourglass-shaped beam. A laser beam is an ideal light source for this task as it contains all of its energy in a collimated coherent plane wave. In the absence of scattering, the cone of light will focus to its narrowest at the waist of the hourglass-shaped beam (Fig. 2), but because of diffraction, the cone will not evenly illuminate the specimen. This distribution is called the point spread function (PSF) because the image of a small luminous point-object has the exact same pattern * The point-by-point signal collection process requires a mechanism for scanning the focused illuminating beam through the specimen volume under observation. . In order to extend the confocal point-sampling principle to allow generation of an extended specimen image field, the point focus in the specimen is scanned in a raster pattern similar to that employed to create the image on a television screen (and in other video applications; see Figure 2(a)). This mechanism requires a fast horizontal sc