At Northeastern University, a coherent imaging process known as Optical Quadrature Microscopy (OQM) has been developed as one of the modalities of the Keck Microscope. This mode was designed for the purpose of non-invasively capturing the amplitude and phase data of an optically transparent sample. This can be used to reconstruct images of the original sample. However, sensors and basic signal processing produce a nonlinearly wrapped phase lying in the range of (-p,p). In the presence of noise, this unwrapping can fail catastrophically, but various methods detailed in [1] have been proposed to solve this problem. We aim to implement a phase unwrapping algorithm on reconfigurable hardware. Current processing methods require several minutes for every frame of data produced by the microscope and our hope is to accelerate that process, so that phase unwrapping takes the same amount of time as image acquisition. Prior to implementation however, it is necessary to decide which algorithm produces the best results in terms of the quality of the output image. A high quality image is one with few discontinuities. The conclusions presented in this poster give the results of our experimentation into the various phase unwrapping procedures popular in the literature and give the current status of the hardware implementation.


Poster presented at the 2006 R3A Parallel Hardware Implementation for Fast Subsurface Detection Conference


Phase Unwrapping, Reconfigurable Hardware, Optical Quadrature Microscopy

Subject Categories



Computer Engineering


Bernard M. Gordon Center for Subsurface Sensing and Imaging Systems (Gordon-CenSSIS)

Publication Date


Rights Holder

Bernard M. Gordon Center for Subsurface Sensing and Imaging Systems (Gordon-CenSSIS)

Click button above to open, or right-click to save.