Voter Facing Scanner

Primary definition

An electronic voting device that: accepts hand-marked or BMD-produced paper ballots one sheet at a time; is usually used for in-person voting ; permits election workers to open and close the polls ; scans a ballot and rejects it if either unreadable or un-processable; detects, interprets and validates contest selections ; notifies the voter of voting exceptions (such as undervotes or overvotes ) or unreadable marks; stores accepted ballots in a secure container; sorts or otherwise marks ballots or ballot images that need subsequent human review; and tabulates and reports contest results after polls are closed. This unit was previously referred to as precinct count optical scanner or PCOS. Synonyms: PCOS , precinct-count optical scanner

Also known asballot scanner · optical scan voting system · OS system · vote scanner · ballot reader · optical scanner
2 sources cited4 related termsReviewed Aug 10, 2026
NIST Election GlossaryView source

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NIST

An electronic voting device that: accepts hand-marked or BMD-produced paper ballots one sheet at a time; is usually used for in-person voting ; permits election workers to open and close the polls ; scans a ballot and rejects it if either unreadable or un-processable; detects, interprets and validates contest selections ; notifies the voter of voting exceptions (such as undervotes or overvotes ) or unreadable marks; stores accepted ballots in a secure container; sorts or otherwise marks ballots or ballot images that need subsequent human review; and tabulates and reports contest results after polls are closed. This unit was previously referred to as precinct count optical scanner or PCOS. Synonyms: PCOS , precinct-count optical scanner

NIST Election Glossary · 2024

Cite this term

Permanent URL · stable across revisions
Election Security Glossary. (2026). Voter Facing Scanner. In Election Security Glossary. Retrieved August 21, 2026, from https://electionsecurityglossary.com/glossary/voter-facing-scanner

Sources

2 cited · last checked Aug 10, 2026

01

NIST Election Glossary
NIST Election Glossary

High consensus

View source

02

EAC Glossary of Terms
EAC Glossary of Terms

Disputed

View source

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