Diagnosis of Unstained Biological Blood Cells Using a Phase Hologram Displayed by a Phase-only Spatial Light Modulator and Reconstructed by a Fourier Lens

• Published in: Current optics and photonics Vol. 6; no. 6; pp. 598 - 607
• Main Author: Ibrahim, Dahi Ghareab Abdelslam
• Format: Journal Article
• Language: Korean
• Published: 2022
• Subjects: 3D reconstruction; Noise reduction; Phase hologram; Cell analysis; Spatial light modulator
• ISSN: 2508-7266; 2508-7274

In this paper, a simple nondestructive technology is used to investigate unstained biological blood cells in three dimensions (3D). The technology employs a reflective phase-only spatial light modulator (SLM) for displaying the phase hologram of the object being tested, and a Fourier lens for its reconstruction. The phase hologram is generated via superposing a digital random phase on the 2D image of the object. The phase hologram is then displayed by the SLM with 256 grayscale levels, and reconstructed by a Fourier lens to present the object in 3D. Since noise is the main problem in this method, the windowed Fourier filtering (WFF) method is applied to suppress the noise of the reconstructed object. The quality of the reconstructed object is refined and the noise level suppressed by approximately 40%. The technique is applied to objects: the National Institute of Standards (NIS) logo, and a film of unstained peripheral blood. Experimental results show that the proposed technique can be used for rapid investigation of unstained biological blood cells in 3D for disease diagnosis. Moreover, it can be used for viewing unstained white blood cells, which is still challenging with an optical microscope, even at large magnification.