Quantitative phase imaging of low-cost digital in-line holography in comparison with off-axis digital holographic microscopy

Digital holographic microscopy (DHM) is a quantitative phase imaging (QPI) modality, which retrieves 3D object phase information. The quantification of subcellular features within the object is possible. Its single-shot hologram recording feature makes it suitable for real-time imaging applications. This paper discusses QPI capability of LED-based digital inline holographic microscopy (LDHM), which has gained much attention for its portability, cost-effective features. However, the twin image artifact is present in the inline setup. Though several twin image reduction and elimination methods are developed, the exact phase quantification is always a challenge. Original phase information may be lost after elimination of twin image. There is always a trade-off between twin-image elimination and QPI of inline microscopy setup. This paper discusses the QPI capability of LDHM in comparison with the conventional off-axis DHM. Further, the results of phase objects using both the methods are studied.