A new methodology for pixel size retention in lensless digital holographic microscopy applied to micro-particle analysis

A new method to control the pixel size corresponding to appropriate magnification is presented for a lensless digital holographic microscopy system. Maintaining the correct pixel size corresponding to the desired magnification at different depths is accomplished by suitably zero padding the digital hologram prior to reconstruction. This is particularly significant for three-dimensional (3D) micro-particle analysis under converging wave reconstruction geometry. Experimental results are presented to demonstrate the improvement in the measurement of the size and depth of micro-particles in three dimensions using lensless in-line digital holographic microscopy