Patent US4814974A successfully refreshed from Google Patents.
Patent US3879707A successfully refreshed from Google Patents.
US3879707A
Expired / Lapsed
US
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Character recognition system for bar coded characters
Assignee: International Business Machines Corp
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Filing: 1972-12-20
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Granted: 1975-04-22
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Expires: 1992-12-20
Abstract
Abstract An improved character recognition system for bar coded characters particularly of the form designated as ''''CMC7,'''' comprising characters formed with seven vertical bars known as strokes, which are separated by intervals of varying widths, the narrow and wide spacings in the intervals or spaces between the strokes comprising the code for the character. The electrical waveform obtained by scanning the characters with a suitable scanning head is differentiated and the signal and the derivative thereof are used in circuits which measure the inter-stroke intervals. Use of the derivative signal from the scanning or read head enhances reading by using it to locate the edges of the printed strokes.
Inventors
- 👤 Gene D Rohrer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:53
CPC Classifications
G; G06; G06V; G06V30/00; G06V30/10; G06V30/22; G06V30/224; G06V30/2247
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
255 words
A character recognition system for recognizing bar coded characters composed of a plurality of vertical bars separated by long or short intervals between the strokes, comprising, in combination scanning means for scanning said characters and producing a scanning signal having a first polarity when said scanning means scans the leading edge of each of said bars, and producing a scanning signal having a second polarity when said scanning means scans the trailing edge of each of said bars, first amplitude discriminating means connected to said scanning means and producing a first output signal when a scanning signal of said first polarity and exceeding a fixed predetermined amplitude is supplied thereto from said scanning means, differentiating means connected to said scanning means to receive said scanning signals and to supply output signals corresponding to the continuous derivative of said scanning signals, second amplitude discriminating means connected to said differentiating means and producing a second output signal when the derivative of said scanning signal exceeds a variable predetermined amplitude, amplitude level control means connected to said second amplitude discriminating means and effective to vary the predetermined amplitude at which said second discriminating means is effective, analyzing means connected to said first and said second amplitude discriminating means for decoding the combinations of signals supplied therefrom to provide output signals indicative of the characters scanned, and bistable means connected to said analyzing means and to said amplitude level control means to provide a binary and hysteretic control of the variable predetermined amplitude of said second amplitude discriminating means.
Claim 2
Dependent Claim
255 words
A character recognition system for recognizing bar coded characters composed of a plurality of vertical bars separated by long or short intervals between the strokes, comprising, in combination scanning means for scanning said characters and producing a scanning signal having a first polarity when said scanning means scans the leading edge of each of said bars, and producing a scanning signal having a second polarity when said scanning means scans the trailing edge of each of said bars, first amplitude discriminating means connected to said scanning means and producing a first output signal when a scanning signal of said first polarity and exceeding a fixed predetermined amplitude is supplied thereto from said scanning means, differentiating means connected to said scanning means to receive said scanning signals and to supply output signals corresponding to the continuous derivative of said scanning signals, second amplitude discriminating means connected to said differentiating means and producing a second output signal when the derivative of said scanning signal exceeds a variable predetermined amplitude, amplitude level control means connected to said second amplitude discriminating means and effective to vary the predetermined amplitude at which said second discriminating means is effective, analyzing means connected to said first and said second amplitude discriminating means for decoding the combinations of signals supplied therefrom to provide output signals indicative of the characters scanned, and bistable means connected to said analyzing means and to said amplitude level control means to provide a binary and hysteretic control of the variable predetermined amplitude of said second amplitude discriminating means.
Claim 3
Dependent Claim
255 words
A character recognition system for recognizing bar coded characters composed of a plurality of vertical bars separated by long or short intervals between the strokes, comprising, in combination scanning means for scanning said characters and producing a scanning signal having a first polarity when said scanning means scans the leading edge of each of said bars, and producing a scanning signal having a second polarity when said scanning means scans the trailing edge of each of said bars, first amplitude discriminating means connected to said scanning means and producing a first output signal when a scanning signal of said first polarity and exceeding a fixed predetermined amplitude is supplied thereto from said scanning means, differentiating means connected to said scanning means to receive said scanning signals and to supply output signals corresponding to the continuous derivative of said scanning signals, second amplitude discriminating means connected to said differentiating means and producing a second output signal when the derivative of said scanning signal exceeds a variable predetermined amplitude, amplitude level control means connected to said second amplitude discriminating means and effective to vary the predetermined amplitude at which said second discriminating means is effective, analyzing means connected to said first and said second amplitude discriminating means for decoding the combinations of signals supplied therefrom to provide output signals indicative of the characters scanned, and bistable means connected to said analyzing means and to said amplitude level control means to provide a binary and hysteretic control of the variable predetermined amplitude of said second amplitude discriminating means.
Claim 4
Dependent Claim
255 words
A character recognition system for recognizing bar coded characters composed of a plurality of vertical bars separated by long or short intervals between the strokes, comprising, in combination scanning means for scanning said characters and producing a scanning signal having a first polarity when said scanning means scans the leading edge of each of said bars, and producing a scanning signal having a second polarity when said scanning means scans the trailing edge of each of said bars, first amplitude discriminating means connected to said scanning means and producing a first output signal when a scanning signal of said first polarity and exceeding a fixed predetermined amplitude is supplied thereto from said scanning means, differentiating means connected to said scanning means to receive said scanning signals and to supply output signals corresponding to the continuous derivative of said scanning signals, second amplitude discriminating means connected to said differentiating means and producing a second output signal when the derivative of said scanning signal exceeds a variable predetermined amplitude, amplitude level control means connected to said second amplitude discriminating means and effective to vary the predetermined amplitude at which said second discriminating means is effective, analyzing means connected to said first and said second amplitude discriminating means for decoding the combinations of signals supplied therefrom to provide output signals indicative of the characters scanned, and bistable means connected to said analyzing means and to said amplitude level control means to provide a binary and hysteretic control of the variable predetermined amplitude of said second amplitude discriminating means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-21 | 1978-10-21 | 1979-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-21 | 1982-10-21 | 1983-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-21 | 1986-10-21 | 1987-04-22 | $7700.00 | Window Closed / Lapsed |