SCANNING APPARATUS FOR THE DETECTION AND IDENTIFICATION OF LUMINESCING CODE BARS ON ARTICLES

• US 3,662,181 A
• Filed: 04/22/1970
• Issued: 05/09/1972
• Est. Priority Date: 04/22/1970
• Status: Expired due to Term

• Current Assignee: Michael Hercher, Michael Madalo
• Original Assignee: Michael Hercher, Michael Madalo
• Inventors: Hercher, Michael, Madalo, Michael
• Primary Examiner(s): Stolwein, Walter
• Application Number:
  US05/030,814
• Time in Patent Office: 748 Days
• Field of Search: 250/223,219D,232,71.5S 209/111.6,111.7
• US Class Current: 235/462.04
• CPC Class Codes: B07C 5/3412 according to a code applied to the object which indicates a property of the object, e.g. quality class, contents or incorrect indication sorting according to size measured by light-responsive means B07C5/10; sorting according to optical properties B07C5/342; for packages B65D79/02; for information carriers G06K7/00
• CPC Class Codes: G01N 21/6456 Spatial resolved fluorescence measurements; Imaging
• CPC Class Codes: G06K 7/10861 sensing of data fields affixed to objects or articles, e.g. coded labels postal sorting B07C3/14, conveying articles B65G47/48

Abstract

A scanning apparatus is provided to identify information encoded in a series of parallel code bars on articles moving on a conveyor. The code bars are each made up of one or more materials capable of emitting light of a distinct color when exposed to ultraviolet light. The bars are illuminated and scanned transversely by an optical system including a focussing lens and a moving belt having a slit. The moving belt is generally opaque to the emitted light from the code bars. The moving belt moves in the focal plane of the lens. A diffusing lens is located behind the belt to diffuse the image received through the slit over a group of photo detectors, each photo detector being optically filtered to respond to one of the distinct colors with an electrical output signal. The output signals of the detectors actuate logic circuitry to identify and/or sort the article.

Claims

1. An apparatus for the scanning of articles passing a scanning station where the articles are provided with parallel spaced and stacked code bars formed of luminescent materials which emit a narrow band of radiation of a preselected wavelength in response to stimulation from a source of radiant energy, comprising means located at the scanning location for imaging a luminescent code bar in an image plane, a color sensitive detector positioned to be illuminated by radiation from the imaged code bars and respond with an electrical signal representative thereof, an opaque movable endless mask having a transparent code-barradiation-passing slit oriented transversely to mask motion and parallel with the code bars, means for mounting the mask for movement between the code bars and the color sensitive detector in a plane generally parallel with the image plane and in the vicinity thereof, said mask traversing the image plane with the slit generally parallel with individual imaged code bars, said belt slit further being sized to permit passage of stimulated radiation from but one code bar at any one time to illuminate the color sensitive detector with radiation from the code bars sequentially in time and space without illumination overlap from adjacent code bars.

2. The apparatus as claimed in claim 1 wherein the mask is located for movement in the image plane.

3. The apparatus as claimed in claim 1 and further including means positioned between the mask and the color sensitive detector for illuminating the light sensitive surface of the detector with imaged code bar radiation from any one code bar.

4. The apparatus as claimed in claim 3 wherein said illuminating means includes a lens arranged and selected to stabilize the code bar radiation on the detector surface.

5. The apparatus as claimed in claim 1 wherein the mask is in the form of an endless belt for repetitive scanning of articles with continuous movement of the belt across the image plane.

6. The apparatus as claimed in claim 5 wherein the endless belt is further provided with a starting slit selectively located with respect to the code bar radiation passing slit to derive position information of the code bar radiation passing slit with respect to the imaged code bars, and means for sensing the position of the start slit and for producing an electrical signal representative of when the code bar radiation passing slit is located in radiation passing relationship with a selected first code bar in the stack of scanned code bars.

7. The apparatus as claimed in claim 1 and further including means for producing a signal for identifying when the slit is in radiation passing relationship with the first code bar in the stack of scanned code bars.

8. The apparatus as claimed in claim 1 wherein the mask is formed of an opaque photographic film strip having a transparent line generally located transversely to the longitudinal dimension of the strip.

9. The apparatus as claimed in claim 8 wherein the film strip is arranged in the form of an endless belt and provided with a plurality of transparent parallel lines selectively spaced from one another along the strip to avoid multiple exposure of the light detector to code bar radiation from more than one line.

10. The apparatus as claimed in claim 1 wherein the color sensitive detector includes a plurality of light detecting elements, each of said light detecting elements being formed with photo detectors, each of said photo detectors being provided with a light discriminating filter selected to pass a predetermined wavelength band from the code bars.

11. The apparatus as claimed in claim 10 and further including means responsive to signals from the photo detectors for generating a decoded output signal indicative of the information represented by the color provided code bars.

12. The apparatus as claimed in claim 11 and further including means responsive to the decoded output signal for sorting said articles in correspondence therewith.

13. An apparatus for the detection and identification of articles by sensing the radiation from luminescent markings selectively located on the articles wherein each marking may be formed of several selected color radiating luminescer materials, comprising means located at a scanning location for imaging light radiated by the markings in an image plane, means producing an endless mask provided with a transparent slit having a predetermined physical size and shape to spatially select one of said imaged luminescent markings, means for moving said mask in a direction to cause a selected traversal of images by the slit, means for diffusing light from images passing through the slit to illuminate a selected area with the light passed through the slit, light discriminating means operatively located facing said diffused light illuminated area for producing in response to said diffused illumination output signals representative of the luminescer materials present in a mark.

14. The apparatus as claimed in claim 13 wherein the light discriminating means includes a plurality of closely spaced substantially coplanar mounted photo detectors, and light filters interposed over the phOto detectors, each of said light filters being selected to pass predetermined light radiations corresponding to the light radiated by a selected one of said luminescer materials.

15. The apparatus as claimed in claim 14 and further including means responsive to signals from the photo detectors for producing a decoded output signal and means responsive to the decoded output signal for sorting the articles in accordance therewith.

16. An apparatus for the detection and identification of articles by sensing the radiation from luminescent markings selectively located on the articles wherein each marking may be formed of several selected color radiating luminescer materials, comprising means for imaging the markings in an image plane with the radiations of the markings selectively arranged in the image plane, an endless opaque belt having a transparent slit with a preselected orientation and with the slit sized to pass radiation of one mark image at a time, means for mounting the belt slit for continuous movement past the imaged markings, a plurality of individual color discriminating and detecting elements operatively facing light passed through the moving slit, each of said elements producing an electrical signal representative of the presence of a wavelength band in said light radiation, a diffusing lens responsive to the imaged luminescent marks passed through the slits, and diffusing lens being sized and located to provide a focal length selected to illuminate all of said light receiving elements with light from one imaged marking and to obtain serial signal groups from the light detecting elements, with each group representative of the colors present in a marking and the serial groups being representative of markings associated with an article.

17. The apparatus as claimed in claim 16 wherein the endless belt is provided with a plurality of transparent slits, each slit being sized to pass the light from but one imaged marking, said slits being evenly spaced from one another by a distance exceeding the image size of all imaged markings on an article.

18. An apparatus for the detection and identification of articles where the articles are provided with coded markings selectively prearranged and each formed of a luminescer material selected to emit a predetermined wavelength band of radiation in response to stimulation from a source of radiant energy, comprising means for imaging the light radiations of the markings in an image plane, an opaque, endless mask having a transparent slit, said slit being sized to limit passage of radiation of one imaged marking at a time, means for mounting the mask slit for movement past the imaged markings, a plurality of individual color discriminating and light detecting elements operatively facing light passed through the moving slit, each of said elements producing an electrical signal representative of the presence of a color in a marking on an article, and means responsive to the electrical signals from the light detecting elements to detect the coding represented by the markings on an article.