Analysis of red blood cell parameters by Talbot-projected fringes

Red blood cell (RBC) anomalies are significant symptoms for identification of health disorders and several blood diseases, which involve the modification of the parameters and biophysical characteristics of such cells. The aim of this study is to measure the three-dimensional phase information of healthy RBCs and their parameters, such as cell diameter, thickness, and hemoglobin (Hb) content, using Talbot-projected fringes. The Talbot image of linear grating is projected onto an RBC slide. The deformed grating lines due to the shape and refractive index of RBCs are recorded by a CCD camera through a 20× microscope objective. Hilbert transform is used to extract the phase image from the deformed projected grating lines. Experimentally calculated values of diameter (8.2  μm), thickness (2.7  μm), and Hb content (28.7  pg/cell) are well within the limits available in the literature. The proposed system is robust and user-friendly and performs the imaging of RBCs with high axial and lateral resolution (2.19  μm).