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Computer Vision


Illusory Contours formed by LED Arrays

This research centred around explaining why the text on LED Arrays appears to be tilted. When text is scrolling on an LED Array the text appears to be orientated approx. 10 degrees off vertical. The project investigated the physiology and psychology of visual perception, and attempted to explain the illusion in those terms.

Automated Inspection of Shadow Masks

This research was done in conjunction with LG Electronics, the objective of which was to detect defects in CRT shadow masks using physiological models of human perception. The main steps involved in this research were first to propose a physiological model which explained why human operators can detect tiny defects in shadow masks, then to construct an inspection system and develop software to simulate the physiological processes.

Automated Inspection of Printed Circuit Boards


This research was a combination of two techniques to be used for the inspection of solder joints. The first technique, shape from stereo, which suffers from the already under-constrained correspondence problem, is further complicated by the specular nature of the solder joints being inspected. The second technique, shape from motion, used the specular nature of the solder joint to its advantage in the same way that structured highlight inspection does. It tracked the virtual features (an example of which being highlights), to assist in recovering the profile of a solder joint.