Improving qualitative phase imaging using error eliminating assist of two-steps phase shifting method in digital holography system

摘要

In this research, the mapping of the path length difference that involves the specimen is proposed for improvingqualitative phase imaging (QPI) techniques. Phase-quality images are developed using the principle of phaseshiftin digital holography and then this system has been applied to investigate biological cells and tissues. Inour setup a microscopic digital holographic interferometer with polarizers and a quarter wave plate has beendesigned for detecting cells specimen. The resulting image contains information of the thickness in any area andthe refractive index of the specimen. Moreover, a quadrature – phase shifting holography (QPSH) technique ispurposed. Experimental results are shown improving QPI. Merits and limitations of this method are alsodescribed.