US5552592A — Slim scan module with dual detectors

Claim 1

Independent Claim 120 words

An optical scanning system for scanning indicia having portions of differing light reflectivity comprising: a light emitter assembly, having a single light source, for emitting a beam of light towards the indicia for reflection therefrom; a first optical detector for receiving light reflected back from a first portion of the indicia; a second optical detector spaced from said first optical detector to bound a channel therewith, and operative for receiving light reflected back from a second portion of the indicia; each said optical detector including a photodetector, a lens and an aperture disposed between said photodetector and said lens; and a scanner for scanning the beam of light in the channel between said optical detectors in scans across the indicia.

Claim 2

Dependent Claim 120 words

An optical scanning system for scanning indicia having portions of differing light reflectivity comprising: a light emitter assembly, having a single light source, for emitting a beam of light towards the indicia for reflection therefrom; a first optical detector for receiving light reflected back from a first portion of the indicia; a second optical detector spaced from said first optical detector to bound a channel therewith, and operative for receiving light reflected back from a second portion of the indicia; each said optical detector including a photodetector, a lens and an aperture disposed between said photodetector and said lens; and a scanner for scanning the beam of light in the channel between said optical detectors in scans across the indicia.

Claim 3

Dependent Claim 32 words

A system according to claim 1, wherein said reflected light from said first and said second portions of the indicia is simultaneously and respectively received by said first and second optical detectors.

Claim 4

Dependent Claim 91 words

A system according to claim 1, wherein the first optical detector produces a first electrical signal corresponding to the differing light reflectivity of the first portion of the indicia and the second detector produces a second electrical signal corresponding to the differing light reflectivity of the second portion of the indicia, and further comprising a first circuit for summing together a first analog signal corresponding to said first electrical signal and a second analog signal corresponding to said second electrical signal to generate a single analog signal representative of said indicia.

Claim 5

Dependent Claim 118 words

A system according to claim 1, further comprising: a base supporting said light emitter assembly and said first and second optical detectors; a first circuit board mounted orthogonal to said base and at one end of said base; a first circuit mounted on said first circuit board; a second circuit board mounted orthogonal to said first circuit board and parallel to said base; a second circuit mounted on said second circuit board; and a flexible electrical cable connecting said first and second circuits to each other, wherein said first and second circuits operate together to produce signals to drive the light source and to process signals corresponding to electrical signals produced by the first and second optical detectors.

Claim 6

Dependent Claim 23 words

A system according to claim 4, wherein the first circuit includes a drive circuit for producing a signal to drive said light source.

Claim 7

Dependent Claim 43 words

A system according to claim 4, wherein the second circuit includes an application specific integrated circuit for producing the signals to drive the light source and for processing the signals corresponding to the electrical signals produced by the first and second optical detectors.

Claim 8

Dependent Claim 54 words

A system according to claim 1, wherein (i) said indicia has bar/space widths in the range of 5.5 to 7.5 mils and is scanned from a distance of 6.6 to 12.75 inches or (ii) said indicia has bar/space widths of over 10 mils and is scanned from a distance of 12.75 to 68 inches.

Claim 9

Dependent Claim 51 words

A system according to claim 1, wherein said scan forms a single scanner line across the indicia and said first portion of said indicia reflects light from a first portion of the scan line and said second portion of the indicia reflects light from a second portion of the scan line.

Claim 10

Dependent Claim 30 words

A system according to claim 8, wherein said first portion of the scan line and said second portion of the scan line include a common portion of the scan line.

Claim 11

Dependent Claim 30 words

A system according to claim 1, wherein each said lens is a Fresnel lens, each said aperture is an elongated thin-slit aperture and each said photodetector is a single photodiode.

Claim 12

Dependent Claim 36 words

A system according to claim 10, wherein each said elongated thin-slit aperture has an longitudinal dimension of approximately 0.25 inches and a dimension perpendicular thereto of at least 0.030 inches and not more than 0.060 inches.

Claim 13

Dependent Claim 48 words

A system according to claim 1, wherein said first optical detector has a first field of view and said second optical detector has a second field of view, different from said first field of view, and each of said detectors receives light only within its field of view.

Claim 14

Dependent Claim 47 words

A system according to claim 12, wherein said system has an operating range, and a portion of said first field of view of the first detector overlaps a portion of said second field of view of the second detector when reading indicia located within said operating range.

Claim 15

Dependent Claim 40 words

A system according to claim 1, wherein said first optical detector and said second optical detector extend between a base on which the light source and the optical detectors are supported and a circuit board mounted parallel to the base.

Claim 16

Dependent Claim 271 words

A self-contained optical scanning module for reading indicia having portions of differing light reflectivity, said module comprising; a base; an emitter, fixedly mounted on said base, for emitting a beam of light; optical means for directing the beam of light toward the indicia; support means, attached to said base, for mounting the optical means for oscillating movement; means for producing a reciprocal motion of the optical means on said support means such that the beam of light scans across said indicia; first detector means for receiving light reflected back from a first portion of the indicia and producing electrical signals corresponding to the differing light reflectivity of the first portion of the indicia; second detector means for receiving light reflected back from a second portion of the indicia and producing electrical signals corresponding to the differing light reflectivity of the second portion of the indicia; a first circuit board mounted orthogonal to said base at one end of said base; a first circuit mounted on said first circuit board; a second circuit board mounted orthogonal to said first circuit board and parallel to said base; a second circuit mounted on said second circuit board; an electrical cable connecting said first and second circuits to each other, wherein said first and second circuits operate together to drive the emitter, to drive the means for producing a reciprocal motion and to process the electrical signals produced by the first and second detector means; and said first and said second detector means being spaced apart on the base and bounding a channel through which the beam of light passes en route to the indicia.

Claim 17

Dependent Claim 271 words

A self-contained optical scanning module for reading indicia having portions of differing light reflectivity, said module comprising; a base; an emitter, fixedly mounted on said base, for emitting a beam of light; optical means for directing the beam of light toward the indicia; support means, attached to said base, for mounting the optical means for oscillating movement; means for producing a reciprocal motion of the optical means on said support means such that the beam of light scans across said indicia; first detector means for receiving light reflected back from a first portion of the indicia and producing electrical signals corresponding to the differing light reflectivity of the first portion of the indicia; second detector means for receiving light reflected back from a second portion of the indicia and producing electrical signals corresponding to the differing light reflectivity of the second portion of the indicia; a first circuit board mounted orthogonal to said base at one end of said base; a first circuit mounted on said first circuit board; a second circuit board mounted orthogonal to said first circuit board and parallel to said base; a second circuit mounted on said second circuit board; an electrical cable connecting said first and second circuits to each other, wherein said first and second circuits operate together to drive the emitter, to drive the means for producing a reciprocal motion and to process the electrical signals produced by the first and second detector means; and said first and said second detector means being spaced apart on the base and bounding a channel through which the beam of light passes en route to the indicia.

Claim 18

Dependent Claim 22 words

A module as in claim 15, wherein the first circuit comprises a drive circuit for producing a signal to drive said emitter.

Claim 19

Dependent Claim 42 words

A module as in claim 15, wherein the second circuit comprises an application specific integrated circuit for producing a signal to drive the means for producing reciprocal motion and for processing the electrical signals produced by the first and second detector means.

Claim 20

Dependent Claim 101 words

A module as in claim 15, wherein the means for producing reciprocal motion includes first and second magnets, one of which is a permanent magnet and the other of which is an electromagnet to which an alternating drive signal is applied, the first magnet is fixedly coupled to the optical means, and the second magnet is mounted on the second circuit board in a position in close proximity to the first magnet, such that application of an alternating drive signal to the electromagnet produces a magnetic field which acts on the permanent magnet to produce reciprocal movement of the optical means.

Claim 21

Dependent Claim 30 words

A module as in claim 15, wherein each of the first and second detector means includes a photodiode and a lens and an aperture between said lens and said photodiode.

Claim 22

Dependent Claim 176 words

A module as in claim 15, wherein the means for producing reciprocal motion of the optical means includes a magnet and a drive means for producing an oscillating force on the magnet, and said support means includes: a member having a first end to which said optical means is attached and a second end opposite said first end to which the magnet is attached, with the optical means, the member and the magnet being dimensioned such that the weight of the magnet balances the weight of the optical means with respect to an axis approximately half way between the mirror and the magnet; a flexible planar spring having a free end fixedly coupled to one of the ends of the member, said flexible planar spring being longer than a distance between one end of the member and the axis but shorter than a distance between the ends of the member such that said planar spring flexes about said axis; and means, attached to said base, for fixedly supporting an opposite end of the flexible planar spring.

Claim 23

Dependent Claim 50 words

A module as in claim 20, wherein: the magnet is a permanent magnet, the drive means is an electromagnet attached to said second circuit board, the planar spring comprises of a pair of flexible strips, and the flexible strips each consist of a sheet formed of a flexible plastic material.

Claim 24

Dependent Claim 67 words

A module as in claim 20, wherein the means for fixedly supporting the opposite end of the flexible planar spring includes: a pedestal attached to the base, said pedestal having an arm extending parallel to the base; and a plate attached to the arm of the pedestal with the opposite end of the flexible planar spring being clamped between the plate and the arm of the pedestal.

Claim 25

Dependent Claim 35 words

A module as in claim 15, wherein said first detector means is disposed proximate to one side of said module and said second detector means is disposed proximate to an opposing side of said module.

Claim 26

Dependent Claim 28 words

A module as in claim 23, wherein said light beam is directed between said first and second detector means and between said base and said second circuit board.

Claim 27

Dependent Claim 30 words

A module as in claim 15, wherein each said detector means includes a Fresnel lens and each said Fresnel lens extends substantially between a top and bottom of said module.

Claim 28

Dependent Claim 37 words

A module as in claim 25, wherein each said Fresnel lens has a major surface area and said module has a cross sectional area, and each said major surface area is approximately one-third said cross sectional area.

Claim 29

Independent Claim 104 words

A method of optically scanning indicia having portions of differing light reflectivity, comprising the steps of: emitting a single beam of light towards the indicia for reflection therefrom; detecting light reflected back from a first portion of the indicia with a first optical detector; separately detecting light reflected back from a second portion of the indicia with a second optical detector spaced from the first detector and bounding a channel therewith; passing said reflected light through a lens and an aperture prior to detection; and scanning the indicia by passing the beam of light in and through said channel bonded by the optical detectors.

Claim 30

Independent Claim 104 words

A method of optically scanning indicia having portions of differing light reflectivity, comprising the steps of: emitting a single beam of light towards the indicia for reflection therefrom; detecting light reflected back from a first portion of the indicia with a first optical detector; separately detecting light reflected back from a second portion of the indicia with a second optical detector spaced from the first detector and bounding a channel therewith; passing said reflected light through a lens and an aperture prior to detection; and scanning the indicia by passing the beam of light in and through said channel bonded by the optical detectors.

Claim 31

Dependent Claim 24 words

A system according to claim 27, wherein said detecting of reflected light from said first and second portions of the indicia is performed simultaneously.

Claim 32

Dependent Claim 46 words

A method according to claim 27, further comprising the steps of: producing a first signal corresponding to the differing light reflectivity of the first portion of the indicia; and producing a second signal corresponding to the differing light reflectivity of the second portion of the indicia.

Claim 33

Dependent Claim 45 words

A method according to claim 29, further comprising the step of summing together a first analog signal corresponding to said first signal and a second analog signal corresponding to said second signal to generate a single analog signal representative of an entirety of said indicia.

Claim 34

Dependent Claim 36 words

A method according to claim 27, wherein said indicia has bar/space widths in the range of 5.5 to 7.5 mils and said scanning is performed at a distance from said indicia of 12.75 inches or less.

Claim 35

Dependent Claim 32 words

A method according to claim 27, wherein said indicia has bar/space widths of over 10 mils and said scanning is performed at a distance from the indicia of 68 inches or less.

Claim 36

Dependent Claim 81 words

A method according to claim 32, wherein: said step of scanning includes forming a single scan line across the indicia, said step of detecting reflected light from said first portion of said indicia includes detecting the reflection off the indicia of light from a first portion of the scan line, and said step of detecting reflected light from said second portion of said indicia includes detecting the reflection off the indicia of light from a second portion of the scan line.

Claim 37

Dependent Claim 31 words

A method according to claim 33, wherein said first portion of the scan line and said second portion of the scan line each include a common portion of the scan line.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1999-09-03	2000-03-04	2000-09-03	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2003-09-03	2004-03-04	2004-09-03	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2007-09-03	2008-03-04	2008-09-03	$7700.00	Window Closed / Lapsed

Slim scan module with dual detectors

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