US3798458A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical scanner including an aperture design for non-synchronous detection of bar codes
Assignee: International Business Machines Corp
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Filing: 1972-10-30
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Granted: 1974-03-19
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Expires: 1992-10-30
Abstract
Abstract What is disclosed is an optical scanner for reading bar codes. The scanner is designed to be held by hand and moved above and across the bar code which is printed on a suitable record substrate. The scanner is composed of a suitable casing containing lamps in the lower portion thereof which illuminate the bar coded record. The illumination is reflected through a unique aperture in the lower surface of the scanner and directed onto a light sensor arrangement such as a photocell. The code marks are in the form of code bars such as black lines separated by white portions. The code consists of ''''single'''' code bars and ''''double'''' code bars which are, in one embodiment, twice the width of the ''''single'''' bars. The aperture arrangement of the scanner is designed according to a scheme such that the resultant signal from the detection of a single bar will always be a known fraction, such as one-half, the amplitude of the signal produced by the detection of a double bar regardless of the changes in speed at which the hand-held scanner is moved across the bar coded record.
Inventors
- 👤 R Buckingham
- 👤 J Davis
- 👤 H Herd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:43
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/10544; G06K7/10821; G06K7/10881
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
277 words
An optical scanner for detecting coded information marks on a record of the type wherein said scanning is effected by relative motion between said scanner and said coded information marks on said record comprising: a support structure, an aperture in said support structure for transmitting variations in light energy reflected from said coded information marks on said record from a predetermined area of said record seen by said aperture, and light sensing means located on said support structure confronting said aperture for converting said variations in light energy transmitted through said aperture into corresponding variations in electrical energy, said coded information marks on said record being manifested as light and dark areas arranged in a coded sequence, given ones of said light and dark areas being of a width W smaller in width than the others of said light and dark areas to provide code information indicia which are distinguishable by width, and wherein the size and shape of said aperture in said support structure are selected to transmit light energy from a total predetermined area of said code record seen by said aperture, said total predetermined area of said code record being seen by said aperture, having a width Wi larger than said width W of said smaller light and dark areas such that said total predetermined area is larger than the area of the smaller code indicia seen by said aperture by a predetermined fraction a having a value less than unity of the area B of the smaller code indicia seen by said aperture so that the total area seen by said aperture is equal to the sum of B plus the product aB.
Claim 2
Dependent Claim
277 words
An optical scanner for detecting coded information marks on a record of the type wherein said scanning is effected by relative motion between said scanner and said coded information marks on said record comprising: a support structure, an aperture in said support structure for transmitting variations in light energy reflected from said coded information marks on said record from a predetermined area of said record seen by said aperture, and light sensing means located on said support structure confronting said aperture for converting said variations in light energy transmitted through said aperture into corresponding variations in electrical energy, said coded information marks on said record being manifested as light and dark areas arranged in a coded sequence, given ones of said light and dark areas being of a width W smaller in width than the others of said light and dark areas to provide code information indicia which are distinguishable by width, and wherein the size and shape of said aperture in said support structure are selected to transmit light energy from a total predetermined area of said code record seen by said aperture, said total predetermined area of said code record being seen by said aperture, having a width Wi larger than said width W of said smaller light and dark areas such that said total predetermined area is larger than the area of the smaller code indicia seen by said aperture by a predetermined fraction a having a value less than unity of the area B of the smaller code indicia seen by said aperture so that the total area seen by said aperture is equal to the sum of B plus the product aB.
Claim 3
Dependent Claim
31 words
An optical scanner for detecting coded information marks on a record according to claim 1 including a light source means mounted in said support structure for illuminating said coded information marks.
Claim 4
Dependent Claim
38 words
An optical scanner for detecting coded information marks on a record according to claim 2 wherein said light source means comprises recesses in the lower portion of said support structure containing a pair of elongated sources of illumination.
Claim 5
Dependent Claim
30 words
An optical scanner for detecting coded information marks on a record according to claim 3 wherein said support structure includes a glass bottom plate below said recesses, and said aperture.
Claim 6
Dependent Claim
24 words
An optical scanner for detecting coded information marks on a record according to claim 4 wherein said light sensing means comprises a silicon cell.
Claim 7
Dependent Claim
27 words
An optical scanner for detecting coded information marks on a record according to claim 4 wherein said light sensing means is connected to a threshold detection device.
Claim 8
Dependent Claim
92 words
An optical scanner for detecting coded information marks on a record according to claim 1 wherein said fraction a is determined by the desired contrast of the optical energy to be detected in accordance with the relationship: desired contrast (B-aB/B+aB) (1-a/1+a) which transposes to a 1 - contrast/1 + contrast such that for a desired contrast the fraction a can be calculated and for a code inDicia of width W the area B and consequently the area B+aB, which is the total area to be seen by said aperture can be determined.
Claim 9
Dependent Claim
44 words
An optical scanner for detecting coded information marks according to claim 1 further including a threshold detection device connected to the output of said light sensing means and including means for detecting between separate levels of said electrical energy from said light sensing means.
Claim 10
Independent Claim
84 words
A method of sensing variable area code indicia having plural standard sizes including scanning said code indicia with respect to an aperture filter having an opening greater than the smallest size of said indicia and less than the greatest size of said indicia, sensing the illumination passing from said scanned code as a function of time, providing a plurality of signal level peaks and valleys, and comparing amplitude levels of signals produced to distinguish between relative sizes of code indicia on an individual basis.
Claim 11
Independent Claim
84 words
A method of sensing variable area code indicia having plural standard sizes including scanning said code indicia with respect to an aperture filter having an opening greater than the smallest size of said indicia and less than the greatest size of said indicia, sensing the illumination passing from said scanned code as a function of time, providing a plurality of signal level peaks and valleys, and comparing amplitude levels of signals produced to distinguish between relative sizes of code indicia on an individual basis.
Claim 12
Dependent Claim
61 words
A method in accordance with claim 9 wherein said scanning of the indicia is performed by moving filter means for filtering light and sensing means for sensing across the surface of means for bearing said code indicia, whereby scanning of numerous indicia can be performed by manually addressing said filter means and sensing means to scan indicia intended to be measured.
Claim 13
Dependent Claim
108 words
In sensing of bar code indicia having a pair of standard widths including narrow and wide bar code indicia the method comprising scanning said bar code indicia with respect to a slit type of optical filter having a width greater than the width W of the narrow bar code indicia and narrower than the width of said wide bar code indicia, sensing the illumination passing from said scanned and filtered bar code indicia as a function of time to provide an output signal having plural peaks and valleys, and comparing amplitude levels of signals produced to distinguish between relative widths of bar code indicia on an individual basis.
Claim 14
Dependent Claim
108 words
In sensing of bar code indicia having a pair of standard widths including narrow and wide bar code indicia the method comprising scanning said bar code indicia with respect to a slit type of optical filter having a width greater than the width W of the narrow bar code indicia and narrower than the width of said wide bar code indicia, sensing the illumination passing from said scanned and filtered bar code indicia as a function of time to provide an output signal having plural peaks and valleys, and comparing amplitude levels of signals produced to distinguish between relative widths of bar code indicia on an individual basis.
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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) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |