Kuypers L C, Dirckx J J J, Decraemer W F
Laboratory of Biomedical Physics, Department of Physics, University of Antwerp, Antwerp, Belgium.
Scanning. 2004 Sep-Oct;26(5):256-8. doi: 10.1002/sca.4950260507.
One of the conditions for a laser scanning microscope to reach its optimal performance is for it to operate at its full numerical aperture (NA). In most commonly used systems, the illumination intensity at the back focal plane of the objective lens is apodized. This paper presents a simple method using a photodiode for checking the actual illumination intensity profile. We show as an example the measured profiles of a laser beam when working with two high-NA immersion objectives in two different confocal systems, and also show that in theoretical studies of the point-spread function, the assumption of a flat compared with a truncated Gaussian beam profile gives rise to severe discrepancies. The measured profiles also serve as an indication of the necessity of a realignment of the optical system.
激光扫描显微镜达到其最佳性能的条件之一是在其全数值孔径（NA）下运行。在大多数常用系统中，物镜后焦平面处的照明强度会进行变迹处理。本文提出了一种使用光电二极管检查实际照明强度分布的简单方法。我们举例展示了在两个不同的共聚焦系统中使用两个高NA浸没物镜时激光束的测量分布，并且还表明，在点扩散函数的理论研究中，与截断高斯光束分布相比，假设为平坦分布会导致严重差异。测量分布也表明了光学系统重新对准的必要性。
