OBSERVATION OF REAL TIME SYNTHESIS OF INDIVIDUAL DNA MOLECULES

表示光照强度的方程和 双透镜系统的整体点扩散函数(PSF)，来自 Richards和Wolf(1959)，并用数值方法进行了求解。 考虑了探测器的孔径。数值计算的影响 探测器孔径的半径、过量填充或 物镜后光圈填充量不足，并使用一只或一只 双光子激发，在整个PSF和集合上 卷，都被考虑在内。初步结果表明， 将物镜填充不足到80%或更高对以下情况影响不大 收集体积的轮廓或尺寸。这些结果是 与使用近轴理论和 伪极轴理论描述了光在焦点上的相同 镜头系统。这些结果并不能解释看起来很大的价值 结构系数(焦点体积轴向与径向纵横比) 在荧光相关光谱(FCS)测量中获得 在我们的实验室(Petra Schwille，Sam Hess，未发表的结果， 1998年)。B·理查兹和E·沃尔夫，《电磁绕射》 光学系统。II.消光体中像场的结构 系统，《伦敦系列学报》，A 253,358-379(1959)。

The equations expressing the intensity of illumination and the overall point-spread function (PSF) of a two-lens system, from Richards and Wolf (1959), were solved numerically, and the effect of a detector aperture was considered. The effects of the numerical aperture, of the radius of the detector aperture, of overfilling or underfilling the objective lens back-aperture, and of using one- or two-photon excitation, on the overall PSF and on the collection volume, were considered. Preliminary results show that the effect of underfilling the objective lens to 80% or higher has little effect on the profile or dimensions of the collection volume. These results are compared with calculations using the paraxial theory and pseudoparaxial theory to describe the light at the focus of the same lens system. These results do not explain the apparently large values of the structure factor (focal volume axial to radial aspect ratio) obtained in fluorescence correlation spectroscopic (FCS) measur ements in our laboratory (Petra Schwille, Sam Hess, unpublished results, 1998). B. Richards and E. Wolf, "Electromagnetic diffraction in optical systems. II. Structure of the image field in an aplanatic system," Proc. R. Soc. London Ser. A 253, 358-379 (1959).