High-dynamic-range quantitative phase imaging with spectral domain phase microscopy

Beckman Laser Institute and the Center for Biomedical Engineering, University of California, Irvine, Irvine, California 92612, USA.
Optics Letters (Impact Factor: 3.29). 11/2009; 34(21):3442-4. DOI: 10.1364/OL.34.003442
Source: PubMed


Phase microscopy for high-dynamic-range quantitative phase-contrast imaging of a transparent phase object was demonstrated. Using a common path Fourier domain optical coherence tomography system, this technique is capable of displacement measurement with a sensitivity of 34 pm. The limitation of 2pi ambiguity restriction was overcome by the use of a phase retrieval approach performed in spectral domain. Two-dimensional quantitative phase imaging of human neonatal dermal keratinocyte cells was demonstrated to evaluate the performance of the system for cell imaging.

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Available from: Lingfeng Yu, Mar 13, 2014
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    • "Furthermore, by extracting the phase term from the interference signal to measure nanostructures, the phase of the OCT signal oscillates 2π rad at every shift of half a wavelength of optical path difference. This renders measurements of the displacement of sample to be limited to less than half a wavelength [26]. "
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    • "When the variation of FP cavity length is large—such that ϕi jumps from -π/2 directly to π/2 or from π/2 directly to -π/2—a phase unwrapping technique can be used to obtain continuous phase or displacement [21]. "
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    • "Previous studies have also demonstrated that SD-OCT can achieve higher displacement sensitivity (DS) compared to the conventional SS-OCT approach. In addition, several methods have been proposed to improve the DS and increase the measurable optical path difference beyond half a wavelength for SD-OCT systems [14] [15]. One such method involves the employment of a thin glass slide on top of the sample to provide a reference plane and produce the interference with the sample, while another includes the implementation of a phase unwrapping algorithm to overcome the 2π ambiguity restriction. "
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