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Electronic reading device

  • US 5,274,610 A
  • Filed: 03/24/1992
  • Issued: 12/28/1993
  • Est. Priority Date: 03/29/1991
  • Status: Expired due to Term
First Claim
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1. An optical reading device, comprising:

  • optical reading means for optically reading bar codes including a time bar code indicating a limit time, correct answer bar codes indicating correct answers, and selected answer bar codes;

    time measuring means for measuring time data; and

    control means for preventing said optical reading means from optically reading when the time data measured by said time measuring means has reached the limit time indicated by the time bar code read by said optical reading means.

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