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Date of Award


Document Type

Campus Access Master's Report

Degree Name

Master of Science in Electrical Engineering (MS)

Administrative Home Department

Department of Electrical and Computer Engineering

Advisor 1

Michael C. Roggemann

Advisor 2

Raymond A. Shaw

Committee Member 1

Jeremy P. Bos


We studied the effect of image enhancement techniques on digital holograms based on an in-line holographic system for air-borne cloud droplet measurements. A super-Gaussian filter is applied to pre-process the padded raw hologram prior to the reconstruction. The size distribution of pre-processed hologram with padding and filtering depicts a shift to the larger diameter of cloud particles due to the dilation of detected particle images. The dilated particles reside within the instrument's detectable size range. Two different padding methods: (1) zero padding and (2) mean padding show almost identical consequence for number concentration and particle size dilation. However, the pre-processed hologram with padding alone results in minimal improvement.