EP0256296A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Apparatus for scanning and reading bar codes
Assignee: PSC Inc
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Filing: 1987-07-09
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Granted: —
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Expires: 2007-07-09
Abstract
Abstract An improved hand-held bar code scanning and reading apparatus which is adapted to be hand-held utilizes anamorphic optics for scanning and reading the code by providing a beam having an oblong cross-section in the nominal plane of the code. The oblong cross-section may be aligned with the bars of the code. The optics does not focus the beam in the longitudinal direction of the cross-section at the nominal plane of the code so that diffraction effects which would otherwise cause rotation of the cross-section of the beam to a position transverse to the bars of the code which would preclude reading of narrow bars, is avoided. The last lens of the anamorphic system may be a cylindrical lens which provides a line focus of a visible marker beam while at the same time providing the oblong cross-section of the beam which scans the code. The light from the vicinity of the code passes through the cylindrical lens and is collected by a toric reflector which projects the incoming light onto a photodetector. Power for operating the source of the scanning beam (a laser diode) is conserved by an opto-electronic system responsive to the movement of the sectors of a rotating beam deflector (a polygon reflector) so as to enable power to be applied to the laser only during the intervals when the beam is disposed within the limits of its scan path.
Inventors
- 👤 Kevork Arackellian
- 👤 John A. Boles
- 👤 Jay M. Eastman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 23:15
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/10544; G06K7/10554; G06K7/10594; G06K7/10683; G06K7/10702; G06K7/10564; G06K7/10584; G06K7/10603; G06K7/10613; G06K7/10792; G06K7/10801; G06K7/10811; G06K2207/00; G06K2207/1018
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
75 words
In a bar code scanning apparatus having a deflector which deflects an optical beam along a scan path in a nominal plane to intersect the bars of a bar code in said plane, the improvement comprising an anamorphic optical system having a plurality of optical elements for providing a first astigmatic focus in said plane and a second orthogonal astigmatic focus alignable generally paralleling the bars of said code and located far beyond said plane.
Claim 2
Dependent Claim
75 words
In a bar code scanning apparatus having a deflector which deflects an optical beam along a scan path in a nominal plane to intersect the bars of a bar code in said plane, the improvement comprising an anamorphic optical system having a plurality of optical elements for providing a first astigmatic focus in said plane and a second orthogonal astigmatic focus alignable generally paralleling the bars of said code and located far beyond said plane.
Claim 3
Dependent Claim
42 words
The improvement according to claim 1 wherein at least one of said first and second focii are provided by a pair of optical elements one of which is disposed a distance equal to its focal length from the focus of the other.
Claim 4
Dependent Claim
33 words
The improvement according to claim 2 wherein said elements are lenses one of which is a cylindrical lens having power in one of said orthogonal directions to provide said one of said focii.
Claim 5
Dependent Claim
98 words
The improvement according to claim 1 wherein the cross-section of said beam in said plane is generally elliptical having its major axis in the tangential plane of said beam alignable in the direction of said bars and its minor axis in the sagittal plane of said beam orthogonal to said major axis, the length of said axes being given by d M /d m =f M /f m where d M and d m are the length of said major and minor axes, respectively, and f M and f m are the focal lengths of said optical elements.
Claim 6
Dependent Claim
56 words
The invention according to claim 1 wherein said apparatus has means for providing a visible marker beam focused along a line congruent to said scan path, said marker beam providing means comprising one of the elements of said anamorphic optical system, said element being a cylindrical lens, and a source of visible light illuminating said lens.
Claim 7
Dependent Claim
51 words
The improvement according to claim 1 where said anamorphic optical system is provided by first, second and third optical elements located successively between said source and said plane, said first element providing a spherical lens having said first focus and said second and third elements being first and second cylindrical lenses.
Claim 8
Dependent Claim
96 words
The improvement according to claim 1 wherein said deflecting element has power which provides said first focus and said second focus is provided by a cylindrical lens beyond said deflecting element toward said plane, and wherein said deflecting element is a reflector having a plurality of facets each with a surface having different power to provide said first focus in said plane with one of said plurality of facets and in a plurality of planes spaced from said last-named plane with others of said plurality of facets, and a cylindrical lens for providing said second focus.
Claim 9
Dependent Claim
119 words
The invention according to claim wherein said deflector is a reflector, said optical beam is provided by a source, said source, said first spherical lens and said first cylindrical lens being disposed adjacent each other on one side of said reflector for projecting said beam upon said reflector at an acute angle of incidence for reflection thereof at an acute angle of reflection towards said second cylindrical lens which is disposed on said one side of said reflector, a photodetector, a reflector focusing light from said plane upon said photodetector, said reflector being disposed between said first cylindrical lens and said deflector and having an aperture there through for passage of said beam to be incident upon said deflector.
Claim 10
Dependent Claim
99 words
In a bar code scanner in which an invisible laser beam is scanned along a line across the bars of said code in a nominal plane in which the bars of said code are disposed, a marker beam system which comprises a cylindrical lens which faces said plane on one sidel thereof for providing a focus along a line generally congruent with the line along which said invisible beam is scanned, and source projecting visible light toward said cylindrical lens and being spaced from the focus of said cylindrical lens on the side thereof opposite to said one side.
Claim 11
Dependent Claim
99 words
In a bar code scanner in which an invisible laser beam is scanned along a line across the bars of said code in a nominal plane in which the bars of said code are disposed, a marker beam system which comprises a cylindrical lens which faces said plane on one sidel thereof for providing a focus along a line generally congruent with the line along which said invisible beam is scanned, and source projecting visible light toward said cylindrical lens and being spaced from the focus of said cylindrical lens on the side thereof opposite to said one side.
Claim 12
Dependent Claim
115 words
In a hand-held bar code scanner having a source providing a beam which is scanned along a scan path of certain length across said code when power is applied to said source, apparatus for conserving said power which comprises a rotating beam deflector having a plurality of facets each of which deflects said beam along said scan path, said deflector having a plurality of ribs defining the limits of said facets, means including said ribs for providing a binary optical signal having different states depending upon whether said beam is being deflected along said scan path, and means for enabling and inhibiting the supply of power to said source and response to said control signal.
Claim 13
Dependent Claim
115 words
In a hand-held bar code scanner having a source providing a beam which is scanned along a scan path of certain length across said code when power is applied to said source, apparatus for conserving said power which comprises a rotating beam deflector having a plurality of facets each of which deflects said beam along said scan path, said deflector having a plurality of ribs defining the limits of said facets, means including said ribs for providing a binary optical signal having different states depending upon whether said beam is being deflected along said scan path, and means for enabling and inhibiting the supply of power to said source and response to said control signal.
References Cited (Backward Citations)
No citation records indexed.
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