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US5196685A Expired / Lapsed US ⏱️ 0.0 years remaining

Bar code reader

Assignee: Eastman Kodak Co
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Filing: 1992-06-18
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Granted: 1993-03-23
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Expires: 2012-06-18
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Abstract

Abstract The present invention relates to a bar code reader for reading bar codes and converting them into resepective alphanumeric code signals. The bar code reader includes a scanner for scanning bar codes presented thereto, a timing pulse generating circuit, a sample and holding means, a pattern memory for storing matching bit patterns for a set of bar codes, and a pattern matching circuit. In operation, levels of a rectangular wave output signal generated by the scanner from scanning a bar code are successively read into the sample and holding means in response to predetermined sequence timing pulses provided by the time pulse generating means to store corresponding data bit pattern output signals. The pattern matching circuit compares the data bit pattern output signals from the sample and holding means with matching bit pattern signals stored in the pattern memory. From such pattern signal comparisions, the pattern matching circuit determines which of the matching bit pattern signals is the most likely to be the bar code in question. The pattern matching circuit then converts the determined most similar matching bit pattern signals into the alphanumeric code signal and outputs it.

Inventors

  • 👤 Masaki Izumi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 13:10
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/14

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 154 words
A bar code reader for reading bar codes recorded on a surface and converting the bar codes into respective alphanumeric code signals corresponding thereto comprising: scanning means for scanning and quantizing the bar codes to generate a respective rectangular wave output signal; sampling and holding means for sampling the rectangular wave output signal from the scanning means at predetermined sequential time periods, and for holding the samples for providing corresponding data bit pattern output signals; memory means for storing matching bit pattern signals corresponding to the respective bar codes to be read; and pattern matching means for comparing the data bit pattern output signals from the sampling and holding means with the matching bit pattern signals stored in the memory means for determining an identified data bit pattern output signal corresponding to the read bar code indicated in the most likely matching bit pattern signals and for generating a representative alphanumeric code output signal.
Claim 2
Dependent Claim 154 words
A bar code reader for reading bar codes recorded on a surface and converting the bar codes into respective alphanumeric code signals corresponding thereto comprising: scanning means for scanning and quantizing the bar codes to generate a respective rectangular wave output signal; sampling and holding means for sampling the rectangular wave output signal from the scanning means at predetermined sequential time periods, and for holding the samples for providing corresponding data bit pattern output signals; memory means for storing matching bit pattern signals corresponding to the respective bar codes to be read; and pattern matching means for comparing the data bit pattern output signals from the sampling and holding means with the matching bit pattern signals stored in the memory means for determining an identified data bit pattern output signal corresponding to the read bar code indicated in the most likely matching bit pattern signals and for generating a representative alphanumeric code output signal.
Claim 3
Dependent Claim 83 words
The bar code reader of claim 1 wherein the pattern matching means comprises means for detecting a number of bits in each of the matching bit pattern signals which have levels that are coincident with corresponding bits of the data bit pattern output signals from the sampling and holding means and determining the maximum number in the detected number of bits, whereby the matching bit pattern signals having the maximum number of bits is determined as the most likely matching bit pattern signals.
Claim 4
Dependent Claim 31 words
The bar code reader of claim 2 wherein the pattern matching means further includes means for converting the determined most likely matching bit pattern signals into the alphanumeric code output signal.
Claim 5
Dependent Claim 160 words
A bar code reader for reading bar codes recorded on a surface comprising: scanning means for scanning a bar code presented to the scanning means and quantizing the scanned bar code to generate a representative rectangular wave output signal; means for sampling the representative rectangular wave output signal from the scanning means at predetermined time intervals, and for holding the sample values for a predetermined time period to provide corresponding data bit pattern output signals; memory means for storing separate matching bit pattern signals and an alphanumeric code signal for each of the bar codes to be read by the scanning means; and pattern matching means for comparing bits of the data bit pattern output signals from the sampling and holding means with corresponding bits of each of the matching bit pattern signals stored in the memory means for determining which one of the matching bit pattern signals most likely corresponds to the bar code read by the scanning means.
Claim 6
Dependent Claim 160 words
A bar code reader for reading bar codes recorded on a surface comprising: scanning means for scanning a bar code presented to the scanning means and quantizing the scanned bar code to generate a representative rectangular wave output signal; means for sampling the representative rectangular wave output signal from the scanning means at predetermined time intervals, and for holding the sample values for a predetermined time period to provide corresponding data bit pattern output signals; memory means for storing separate matching bit pattern signals and an alphanumeric code signal for each of the bar codes to be read by the scanning means; and pattern matching means for comparing bits of the data bit pattern output signals from the sampling and holding means with corresponding bits of each of the matching bit pattern signals stored in the memory means for determining which one of the matching bit pattern signals most likely corresponds to the bar code read by the scanning means.
Claim 7
Dependent Claim 22 words
The bar code reader of claim 4 wherein the representative rectangular wave output signal from the scanning means is a binarized signal.
Claim 8
Dependent Claim 57 words
The bar code reader of claim 4 wherein each of the sample values being held in the sampling and holding means comprises either a high or a low level value corresponding to the level value of the rectangular wave output signal during the time of a sampling for forming bits of the data bit pattern output signals.
Claim 9
Dependent Claim 89 words
The bar code reader of claim 4 wherein the pattern matching means comprises: means for detecting a number of bits in each of the matching bit pattern signals which have levels that are coincident with corresponding bits of the data bit pattern output signals from the sampling and holding means; and means for determining the maximum number of coincident levels in the detected number of corresponding bits, whereby the matching bit pattern signals having the maximum number of bits is determined as the most likely matching bit pattern signals.
Claim 10
Dependent Claim 31 words
The bar code reader of claim 7 wherein the pattern matching means further includes means for converting the determined most likely matching bit pattern signals into an alphanumeric code output signal.
Claim 11
Dependent Claim 41 words
The bar code reader of claim 4 further comprising timing pulse generating means responsive to the rectangular wave output signal from the scanning means for generating timing pulses at the predetermined time intervals for transmission to the sampling and holding means.
Claim 12
Dependent Claim 17 words
The bar code reader of claim 9 wherein the timing pulses have a constant interval between pulses.
Claim 13
Dependent Claim 59 words
The bar code reader of claim 9 wherein the timing pulses are generated at uneven intervals whereby sampling by the sampling and holding means is performed at least in a central portion of each of a bar and a space of the bar code being scanned to accommodate a variation in a bar-to-space format ratio of the bar code.
Claim 14
Dependent Claim 37 words
The bar code reader of claim 9 wherein the timing pulses have intervals for providing at least two timing pulses during each of a bar and a space of the bar code scanned by the scanning means.
Claim 15
Independent Claim 147 words
A method for reading bar codes recorded on a surface comprising the steps of: (a) scanning a bar code and quantizing the scanned bar code for generating a representative rectangular wave output signal; (b) sampling the representative rectangular wave output signal at predetermined time intervals, and holding the sample values for a predetermined time period for providing corresponding data bit pattern output signals; (c) storing separate matching bit pattern signals and an alphanumeric code signal for each of the bar codes to be read by the scanning means in a memory means; and (d) comparing bits of the data bit pattern output signals associated with the detected bar code with corresponding bits of each of the matching bit pattern signals stored in the memory means for determining which one of the matching bit pattern signals most likely corresponds to the bar code read by the scanning means.
Claim 16
Independent Claim 147 words
A method for reading bar codes recorded on a surface comprising the steps of: (a) scanning a bar code and quantizing the scanned bar code for generating a representative rectangular wave output signal; (b) sampling the representative rectangular wave output signal at predetermined time intervals, and holding the sample values for a predetermined time period for providing corresponding data bit pattern output signals; (c) storing separate matching bit pattern signals and an alphanumeric code signal for each of the bar codes to be read by the scanning means in a memory means; and (d) comparing bits of the data bit pattern output signals associated with the detected bar code with corresponding bits of each of the matching bit pattern signals stored in the memory means for determining which one of the matching bit pattern signals most likely corresponds to the bar code read by the scanning means.
Claim 17
Dependent Claim 19 words
The method of claim 13 wherein in step (a) the representative rectangular wave output signal is a binarized signal.
Claim 18
Dependent Claim 49 words
The method of claim 13 wherein in step (b) each of the sample values comprises either a high or a low level value corresponding to the level value of the rectangular wave output signal during the time of a sampling for forming bits of the data bit pattern signals.
Claim 19
Dependent Claim 80 words
The method of claim 13 wherein step (d) comprises the substeps of: (d1) detecting a number of bits in each of the matching bit pattern signals which have levels that are coincident with corresponding bits of the data bit pattern output signals; and (d2) determining the maximum number of coincident levels in the detected number of corresponding bits, whereby the matching bit pattern signals having the maximum number of bits is determined as the most likely matching bit pattern signals.
Claim 20
Dependent Claim 29 words
The method of claim 16 wherein step (d) further includes the step of: (d3) converting the determined most likely matching bit pattern signals into an alphanumeric code output signal.
Claim 21
Dependent Claim 37 words
The method of claim 13 wherein prior to step (b) performing the step of: (e) generating timing pulses at the predetermined time intervals for use in sampling the representative rectangular wave output signal at predetermined time intervals.
Claim 22
Dependent Claim 15 words
The method of claim 18 wherein the timing pulses have a constant interval between pulses.
Claim 23
Dependent Claim 49 words
The method of claim 18 wherein the timing pulses have uneven intervals whereby sampling is performed at least in a central portion of each of a bar and a space of the bar code being scanned to accommodate a variation in a bar-to-space format ratio of the bar code.

References Cited (Backward Citations)

US4074115A Cited
US4239151A Cited
US4902883A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-03-22 1996-09-21 1997-03-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-03-22 2000-09-21 2001-03-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-03-22 2004-09-21 2005-03-23 $7700.00 Window Closed / Lapsed

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