Comparison of three dimensional transfer function analysis of alternative phase imaging methods

Abstract

Phase imaging is an invaluable tool for observation of biological sample, especially for living cells, where staining might not be appropriate, or for materials that do not absorb stain. Imaging of phase distributions with high spatial resolution can be used to derive the actual thickness and refractive index variations in the specimen. The detection of very small phase variations enables the detailed structure in the specimen to be revealed. As a result, the development and utilization of various phase imaging modalities have been important aspects of microscopy research. Differential Interference Contrast (DIC) and Quantitative Phase Microcopy (QPM) are based on partially coherent light, thus enabling high-resolution imaging. However, the low coherence requirement prevents the acquisition of quantitative phase data directly. On the other hand, Digital Holography Microscopy (DHM) is able to yield quantitative phase information but is compromised on resolution and cannot give full three dimensional (3D) reconstructions. In this paper, we present the 3D theoretical formalism of the above mentioned phase imaging methods with the focus on DHM. A comparative analysis here through visualization of 3D optical transfer functions gives an insight into the behaviors of these phase imaging methods.