US5814803A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image reader with multi-focus lens
Assignee: Datalogic Scanning Inc
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Filing: 1995-12-21
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Granted: 1998-09-29
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Expires: 2015-12-21
Abstract
Abstract A method and apparatus for reading bar codes or other images while reducing or eliminating the need for self-generated illumination. An image reader is preferably embodied as a handheld unit and comprises an efficient optical collection system including an aperture with a high aspect ratio and/or a multi-focal lens or lenses. An optically transmissive spacer affixed to the front of the handheld unit allows ambient light to be collected at close range, and a diffuser may be used to reflect ambient light from the handheld unit to provide additional illumination at close range. A masked CCD detector with rectangular pixels receives collected light and is coupled to an adaptive exposure circuit for preventing saturation of the CCD detector at high illumination levels. A correlated double sampling circuit coupled to the adaptive exposure circuit rejects common mode noise and allows operation in lower light levels. The correlated double sampling circuit is connected to a signal processor which uses a derivative based technique for detecting edges of the image. A decoder uses the edge detection information to decode encoded information from the image.
Inventors
- 👤 Bryan L. Olmstead
- 👤 Michael J. Ahten
- 👤 Bruce E. Paris
- 👤 Jorge L. Acosta
- 👤 James W. Ring
- 👤 Paul R. Huss
- 👤 Jon P.C. Williams
- 👤 Alexander M. McQueen
- 👤 Randy L. Person
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:03
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/10544; G06K7/10821; G06K7/10851; G06K7/10554; G06K7/10594; G06K7/10683; G06K7/10702; G06K7/10712; G06K7/10722; G06K7/10752; G06K7/10792; G06K7/10801; G06K7/10811; G06K7/10881
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
68 words
A bar code reader comprising a multi-focus ambient light gathering system comprising a lens having a plurality of zones, each zone having a different focal length; means for reducing interference between said zones caused by simultaneous gathering of ambient light; a photo-sensitive detector outputting a signal having an amplitude varying in response to lighter and darker portions of a read image; and a decoder coupled to said signal.
Claim 2
Dependent Claim
68 words
A bar code reader comprising a multi-focus ambient light gathering system comprising a lens having a plurality of zones, each zone having a different focal length; means for reducing interference between said zones caused by simultaneous gathering of ambient light; a photo-sensitive detector outputting a signal having an amplitude varying in response to lighter and darker portions of a read image; and a decoder coupled to said signal.
Claim 3
Dependent Claim
68 words
A handheld bar code reader comprising a photosensitive detector outputting a signal indicative of a level of received light; a multi-focus lens having a plurality of concentric zones, said multi-focus lens positioned so as to focus ambient light on said photosensitive detector; an aperture positioned along a central axis of said lens, said aperture having a non-unity aspect ratio; and an edge detector coupled to said photosensitive detector.
Claim 4
Dependent Claim
68 words
A handheld bar code reader comprising a photosensitive detector outputting a signal indicative of a level of received light; a multi-focus lens having a plurality of concentric zones, said multi-focus lens positioned so as to focus ambient light on said photosensitive detector; an aperture positioned along a central axis of said lens, said aperture having a non-unity aspect ratio; and an edge detector coupled to said photosensitive detector.
Claim 5
Dependent Claim
22 words
The handheld bar code reader of claim 2 wherein said photosensitive detector comprises a CCD detector having an array of rectangular pixels.
Claim 6
Dependent Claim
19 words
The handheld bar code reader of claim 3 further comprising a mask positioned in from of said photosensitive detector.
Claim 7
Dependent Claim
52 words
The handheld bar code reader of claim 2 further comprising a housing including a handle portion and a head portion, said head portion comprising an imaging window positioned to allow ambient light to be collected by said multi-focus lens and further comprising an optically transmissive spacer in front of said imaging window.
Claim 8
Dependent Claim
19 words
The handheld bar code reader of claim 2 further comprising an adaptive exposure circuit connected to said photosensitive detector.
Claim 9
Dependent Claim
21 words
The handheld bar code reader of claim 2 further comprising means connected to said photosensitive detector for reducing common mode noise.
Claim 10
Dependent Claim
17 words
The handheld bar code reader of claim 2 further comprising means for enhancing transitions in said signal.
Claim 11
Dependent Claim
27 words
The handheld bar code reader of claim 8 wherein said means for enhancing transitions in said signal comprises a finite impulse response filter coupled to a comparator.
Claim 12
Dependent Claim
27 words
The handheld bar code reader of claim 8 wherein said means for enhancing transitions in said signal comprises an infinite impulse response filter coupled to a comparator.
Claim 13
Dependent Claim
17 words
The handheld bar code reader of claim 2 further comprising a decoder connected to said edge detector.
Claim 14
Dependent Claim
21 words
The handheld bar code reader of claim 2 further comprising at least one light emitting diode for generating an aiming beam.
Claim 15
Dependent Claim
21 words
The handheld bar code reader of claim 12 further comprising an optical diffuser positioned in the path of said aiming beam.
Claim 16
Dependent Claim
43 words
The handheld bar code reader of claim 2 wherein each zone of said multi-focus lens provides a different field of view, each field of view progressively narrowing from the zone with the shortest focal distance to the zone with the longest focal distance.
Claim 17
Dependent Claim
39 words
The handheld bar code reader of claim 2 further comprising means for focusing along multiple axes by selectively magnifying an image along each of said multiple axes to generate a plurality of magnified images and combining the magnified images.
Claim 18
Dependent Claim
30 words
The handheld bar code reader of claim 2 further comprising a kaleidoscope mirror, wherein said photosensitive detector comprises an area array for receiving multiple images reflected from said kaleidoscope mirror.
Claim 19
Dependent Claim
23 words
The handheld bar code reader of claim 2 further comprising a mirror basket for receiving and reproducing an image in a repeating pattern.
Claim 20
Dependent Claim
135 words
A bar code reader comprising: a light sensitive detector; a lens comprising a rectangular cut-away portion of a round poly-optic lens having a plurality of zones, a first zone comprising a round center portion and each successive zone comprising a concentric ring-shaped lens portion surrounding the preceding zone, at least two of said zones having different focal distances, whereby light reflected from a bar code is focused separately by each zone onto said light sensitive detector; a signal output from said light sensitive detector having information corresponding to relatively light portions and darker portions of said bar code; and a decoder coupled to said light sensitive detector, said decoder comprising an edge detector for detecting transitions in said signal corresponding to transitions from the relatively light portions to the darker portions of said bar code.
Claim 21
Dependent Claim
135 words
A bar code reader comprising: a light sensitive detector; a lens comprising a rectangular cut-away portion of a round poly-optic lens having a plurality of zones, a first zone comprising a round center portion and each successive zone comprising a concentric ring-shaped lens portion surrounding the preceding zone, at least two of said zones having different focal distances, whereby light reflected from a bar code is focused separately by each zone onto said light sensitive detector; a signal output from said light sensitive detector having information corresponding to relatively light portions and darker portions of said bar code; and a decoder coupled to said light sensitive detector, said decoder comprising an edge detector for detecting transitions in said signal corresponding to transitions from the relatively light portions to the darker portions of said bar code.
References Cited (Backward Citations)
US2811081A
Cited
US3004470A
Cited
US3801775A
Cited
US4000397A
Cited
US4354101A
Cited
US4135161A
Cited
US4246612A
Cited
US4335302A
Cited
US4691367A
Cited
US4612437A
Cited
US4675513A
Cited
US4687912A
Cited
US4697098A
Cited
JPS61285404A
Cited
US4740675A
Cited
US4843222A
Cited
US4782220A
Cited
US4818886A
Cited
US4879456A
Cited
US4749879A
Cited
US4874933A
Cited
JPS6474687A
Cited
US4861972A
Cited
US4861972B1
Cited
US5155344A
Cited
US4978860A
Cited
US5103209A
Cited
US5010241A
Cited
US5081540A
Cited
US5081541A
Cited
US4939356A
Cited
US5408081A
Cited
US5446272A
Cited
US5291005A
Cited
US4963719A
Cited
US5272323A
Cited
US5442480A
Cited
US5144118A
Cited
US5155343A
Cited
US5126544A
Cited
US5121009A
Cited
US5229797A
Cited
US5071207A
Cited
US5124537A
Cited
US5103080A
Cited
US5144460A
Cited
US5200597A
Cited
US5296690A
Cited
US5285314A
Cited
US5210398A
Cited
US5311001A
Cited
US5202784A
Cited
US5475206A
Cited
US5349172A
Cited
US5329104A
Cited
US5319181A
Cited
US5430282A
Cited
US5378881A
Cited
US5343028A
Cited
US5329105A
Cited
US5347121A
Cited
WO1994015314A1
Cited
US5463211A
Cited
US5304787A
Cited
US5386105A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-09-28 | 2002-03-30 | 2002-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-09-28 | 2006-03-30 | 2006-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-09-28 | 2010-03-30 | 2010-09-29 | $7700.00 | Window Closed / Lapsed |