Crist said he hopes to have all the state's touch-screen machines replaced by optical scan systems in time for next year's presidential election.

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The solution: Smith advocates an optical scan system where voters fill out a paper ballot that's subsequently scanned to create a digital vote.

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The county didn't have enough time to purchase optical scan machines for each polling place, which would have helped to detect errors on the spot, giving voters a chance to correct them.

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In Virginia and North Carolina, rain caused problems for counties using optical-scan paper ballots after water dripping off of wet voters rendered the ballots unreadable by scanners.

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There it was, all long and thin, and I thought, let me scan it and OCR (optical character recognition) it.

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Optical Coherence Tomography (OCT) is a scan that measures the thickness of the lining at the back of the eye - the retina.

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