A Study on Spatial Resolution Enhancement Using Real-ESRGAN in Digital Holographic Microscopy (DHM)

Digital Holographic Microscopy (DHM) is an imaging technique that has been widely used in biological and medical research. However, the spatial resolution of DHM is often limited by numerical aperture (NA) of the objective lens. In the present thesis, a novel approach is proposed to enhance the resolution of DHM images by utilizing the Real-ESRGAN algorithm in combination with a low NA of the objective lens. Acquiring images using a low NA objective lens and subsequently applying the Real-ESRGAN algorithm enables the attainment of higher resolution images comparable to those obtained with a higher NA objective lens, while maintaining cost-effectiveness. Experiments were conducted on real-world DHM datasets to evaluate the performance of the approach. As a result, our proposed approach can effectively enhance the resolution of DHM images, revealing finer details that were previously unattainable with a low NA objective lens alone. Our approach has the potential to significantly reduce the cost of DHM imaging by utilizing lower NA objective lenses while achieving a comparable resolution to higher NA lenses, which makes it a promising technique for a wider application in the biological and medical field.