US3868636A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical character reader having feature recognition capability
Assignee: Isotec Inc
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Filing: 1973-06-18
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Granted: 1975-02-25
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Expires: 1993-06-18
Abstract
Abstract The invention is applicable to single line, multiple line and page reading applications. An optical character reader includes an electro-optical sensor for scanning a line of graphic characters on a character bearing medium to derive electrical signals corresponding to configurations of the characters. A sensor processor amplifies the signals, quantizes the amplified signals and correlates them to reduce the effects of optical noise. A feature generation circuit including a plurality of feature data generators applies predetermined tests to determine the presence or absence of specified character features and forwards corresponding feature data signals to an algorithm circuit. The algorithm circuit applies predetermined criteria to the feature data signals according to truth tables set up for the several forms of characters recognizable by the system, to identify the characters being read. The algorithm circuit produces decimal data which is fed to a decimal to binary converter.
Inventors
- 👤 Arthur Schlang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:17
CPC Classifications
G; G06; G06V; G06V10/00; G06V10/10; G06V10/12; G06V30/00; G06V30/10; G06V30/14; G06V30/146; G06V30/18; G06V30/184
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
279 words
An optical character reader for optically reading characters of a font of two dimensional plane characters based on an ideal regular plane matrix of two mutually perpendicular sets of linear strokes comprising: a plurality of electro-optical sensor means arranged consecutively in an array, which is disposed to scan said characters one at a time while said characters are moved relative to said array in a direction of movement perpendicular to said array in the plane of said matrix and parallel to one of said sets of strokes and, to produce electrical signals corresponding to configurations of said characters, sensor processing means in circuit with said sensor means and arranged to amplify said signals, quantize said amplified signals, and correlate said quantized signals to reduce effects of optical noise, a feature generator means connected to said sensor processing means and arranged to apply several predetermined tests to determine the absence or pResence of certain specified features: said feature generator means comprising: a first circuit means for determining the height of said characters; a logic circuit means for counting the number of times each of said electro-optical sensor means detects one or more of the strokes parallel to said array of said characters as said characters longitudinally traverse said sensor means; and a count sequence circuit means connected to said first circuit means and said logic circuit means for determining the consecutive number of said electro-optical sensing means which have counted the same number of strokes, parallel to said array of said characters; and an algorithm circuit in circuit with said feature generator means for applying predetermined criteria to data communicated therefrom, to ascertain the identity of said characters being read.
Claim 2
Dependent Claim
279 words
An optical character reader for optically reading characters of a font of two dimensional plane characters based on an ideal regular plane matrix of two mutually perpendicular sets of linear strokes comprising: a plurality of electro-optical sensor means arranged consecutively in an array, which is disposed to scan said characters one at a time while said characters are moved relative to said array in a direction of movement perpendicular to said array in the plane of said matrix and parallel to one of said sets of strokes and, to produce electrical signals corresponding to configurations of said characters, sensor processing means in circuit with said sensor means and arranged to amplify said signals, quantize said amplified signals, and correlate said quantized signals to reduce effects of optical noise, a feature generator means connected to said sensor processing means and arranged to apply several predetermined tests to determine the absence or pResence of certain specified features: said feature generator means comprising: a first circuit means for determining the height of said characters; a logic circuit means for counting the number of times each of said electro-optical sensor means detects one or more of the strokes parallel to said array of said characters as said characters longitudinally traverse said sensor means; and a count sequence circuit means connected to said first circuit means and said logic circuit means for determining the consecutive number of said electro-optical sensing means which have counted the same number of strokes, parallel to said array of said characters; and an algorithm circuit in circuit with said feature generator means for applying predetermined criteria to data communicated therefrom, to ascertain the identity of said characters being read.
Claim 3
Dependent Claim
76 words
An optical character reader as recited in claim 1 further including a scan means for providing that an image of each of said characters moves in said direction while it is scanned in a second direction orthogonal to said direction by said sensor means and wherein said scan means includes means for scanning all of said electro-optical sensor means at least once each time said images moves the width of one of said electro-optical sensor means.
Claim 4
Dependent Claim
65 words
An optical character reader as recited in claim 1 wherein said sensor processing means includes a leading edge signal means for producing a single leading edge signal in response to electric signals from at least two consecutively positioned sensor means and wherein said feature generator means includes a counting circuit means connected to said leading edge signal means which counts of said leading edge signal.
Claim 5
Dependent Claim
44 words
An optical character reader as recited in claim 3 wherein said counting circuit means is connected to a counting logic means for counting said leading edge signals only if a subsequent scan has a greater number of leading edge signals than the preceding scan.
Claim 6
Dependent Claim
35 words
An optical character reader as recited in claim 3 wherein said counting circuit means is connected to a logic circuit means for determining whether the last scan of a character has only one leading edge.
Claim 7
Dependent Claim
51 words
An optical character reader as recited in claim 4 further including zonal circuit means for dividing the height of said character image into a plurality of zones and a processing circuit means coupled to said zonal circuit means and said counting logic means for determining the zone of said leading edge.
Claim 8
Dependent Claim
30 words
An optical character reader as recited in claim 4 further including longitudinal division circuit means connected to said counting logic means for determining the longitudinal section of said leading edges.
Claim 9
Dependent Claim
58 words
An optical character reader as recited in claim 3 further including a saddle circuit means connected to said leading edge signal means of said sensor processing means for determining whether said character image has a fall which exceeds a percentage of said character height and is followed by a rise that exceeds said percentage of said character height.
Claim 10
Dependent Claim
229 words
An optical character reader comprising: a plurality of electro-optical sensor means arranged consecutively in an array and disposed for scanning a plurality of graphic characters on a medium, one at a time while said characters are moved relative to said array in a direction of movement perpendicular to said array to derive electric signals corresponding to configurations of said characters: a scan means for providing that an image of each of said characters moves in said direction while it is scanned in a second direction orthogonal to said direction by said sensor means; a sensor processing means connected with said sensor means and arranged to amplify said signals, quantize said amplified signals, and correlate said quantize signals to reduce effects of optical noise, said sensor processing means including a leading edge signal means for producing a single leading edge signal in response to electric sIgnals from at least two consecutive sensor means; a feature generator means connected to said sensor processing means and arranged to apply several predetermined tests to determine the absence or presence of certain specified features; said feature generator means comprising: a counting circuit means connected to said leading edge signal means which counts said leading edge signal; and an algorithm circuit connected with said feature generator means and for applying predetermined criteria to data communicated therefrom to ascertain the identity of said characters being read.
Claim 11
Dependent Claim
229 words
An optical character reader comprising: a plurality of electro-optical sensor means arranged consecutively in an array and disposed for scanning a plurality of graphic characters on a medium, one at a time while said characters are moved relative to said array in a direction of movement perpendicular to said array to derive electric signals corresponding to configurations of said characters: a scan means for providing that an image of each of said characters moves in said direction while it is scanned in a second direction orthogonal to said direction by said sensor means; a sensor processing means connected with said sensor means and arranged to amplify said signals, quantize said amplified signals, and correlate said quantize signals to reduce effects of optical noise, said sensor processing means including a leading edge signal means for producing a single leading edge signal in response to electric sIgnals from at least two consecutive sensor means; a feature generator means connected to said sensor processing means and arranged to apply several predetermined tests to determine the absence or presence of certain specified features; said feature generator means comprising: a counting circuit means connected to said leading edge signal means which counts said leading edge signal; and an algorithm circuit connected with said feature generator means and for applying predetermined criteria to data communicated therefrom to ascertain the identity of said characters being read.
Claim 12
Dependent Claim
21 words
An optical character reader as recited in claim 9 wherein said counting circuit means is connected to a counting logic means.
Claim 13
Dependent Claim
59 words
An optical character reader as recited in claim 9 further comprising: a means for illuminating said characters on said medium while they are being scanned; and an automatic gain control means in said sensor processing means arranged to correct for variations in illumination of said characters in surface reflectance of said medium, and in light absorptivity of graphic characters.
Claim 14
Dependent Claim
102 words
An optical character reader as recited in claim 9 wherein said feature generator means further includes a plurality of feature data generator circuits arranged to receive processed signals from said sensor processing means corresponding to configurations of said scanned characters, each one of said feature data generator circuits being responsive to said processed signals and arranged to generate data signals corresponding to at least one predetermined character feature selected from the following group of character features: character height, horizontal strokes, final value, vertical strokes, saddle, character width, upper stroke slope, blobs and smudges, precipitous fall, final 1 count, and third stroke slope.
Claim 15
Dependent Claim
40 words
An optical character reader as recited in claim 9 further comprising adjustment means arranged to move said medium in one of said directions to position characters on said medium in an optimum position for being scanned by said electro-optical means.
Claim 16
Dependent Claim
58 words
An optical character reader as recited in claim 9, wherein said algorithm circuit, comprises separate logic circuits, one for each preferred form of character to be read, each one of said logic circuits containing components arranged to correlate data signals received from said feature data generator circuits with different character forms each defined by a corresponding truth table.
Claim 17
Dependent Claim
56 words
An optical character reader as recited in claim 14, wherein each of said logic circuits produces decimal data corresponding to character forms recognized by said algorithm circuit and further comprising a decimal to binary conversion circuit connected to said algorithm circuit for producing binary data signals corresponding to the character forms recognized by said algorithm circut.
References Cited (Backward Citations)
US3140466A
Cited
US3160855A
Cited
US3568151A
Cited
US3582883A
Cited
US3587047A
Cited
US3613081A
Cited
US3651461A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |