Das Bhargab, Yelleswarapu Chandra S, Rao Dvgln
University of Massachusetts Boston, Physics Department, 100 Morrissey Blvd, Boston, MA MA 02125, United States.
Opt Commun. 2012 Nov 1;285(24):4954-5960. doi: 10.1016/j.optcom.2012.07.101.
We present a digital holography microscopy technique based on parallel-quadrature phase-shifting method. Two π/2 phase-shifted holograms are recorded simultaneously using polarization phase-shifting principle, slightly off-axis recording geometry, and two identical CCD sensors. The parallel phase-shifting is realized by combining circularly polarized object beam with a 45° degree polarized reference beam through a polarizing beam splitter. DC term is eliminated by subtracting the two holograms from each other and the object information is reconstructed after selecting the frequency spectrum of the real image. Both amplitude and phase object reconstruction results are presented. Simultaneous recording eliminates phase errors caused by mechanical vibrations and air turbulences. The slightly off-axis recording geometry with phase-shifting allows a much larger dimension of the spatial filter for reconstruction of the object information. This leads to better reconstruction capability than traditional off-axis holography.
我们提出了一种基于并行正交相移方法的数字全息显微镜技术。利用偏振相移原理、略微离轴的记录几何结构以及两个相同的电荷耦合器件（CCD）传感器，同时记录两个π/2相移全息图。通过偏振分束器将圆偏振物光束与45°偏振参考光束组合来实现并行相移。通过将两个全息图相互相减来消除直流项，并在选择实像的频谱后重建物体信息。给出了振幅和相位物体的重建结果。同时记录消除了由机械振动和空气湍流引起的相位误差。具有相移的略微离轴记录几何结构允许在重建物体信息时使用更大尺寸的空间滤波器。这导致比传统离轴全息术更好的重建能力。
