A common-path digital holographic microscope with a rotatable birefringent prism for synthesizing high-quality quantitative phase images from multi-angle interferograms

Abstract

We propose a simple common-path off-axis interferometric system to perform high-quality quantitative phase imaging based on a rotatable birefringent prism that is placed at the output port of a conventional transmission or reflection microscope. The proposed system effectively eliminates the zero-order term of holographic data and increases the phase image reconstruction bandwidth by compounding multi-angle holograms, thereby obtaining high-quality quantitative phase images without zero-order artifacts. In addition, the proposed multi-angle phase image compounding method can eliminate the repetitive object phases caused by self-reference interferometry, thereby alleviating the problem of field-of-view reduction. Furthermore, we realize high-quality quantitative phase imaging based on multi-angle phase images without sacrificing the imaging frame rate. The concept is demonstrated by performing high-quality quantitative phase imaging of polystyrene microspheres and a freshwater alga, Pinnularia. Experimental results show that the noise level of the quantitative phase images synthesized using the proposed rotatable common-path digital holographic microscopy system is lower than that of conventional single-shot digital holographic microscope reconstruction quantitative images, and a more detailed cell internal structure can be observed.

Keywords

• Digital holographic microscopy
• DHM
• Common optical path
• Interferometer
• Spatial frequency spectrum
• Quantitative phase image