Optically-based system for processing banknotes based on security feature emissions

• US 20020105654A1
• Filed: 03/04/2002
• Published: 08/08/2002
• Est. Priority Date: 11/25/1997
• Status: Active Grant

• Current Assignee: Spectra Systems Corporation
• Original Assignee: Spectra Systems Corporation
• Inventors: Goltsos, William
• Granted Patent: US 6,744,525 B2
• Time in Patent Office: Days
• US Class Current: 356/601
• 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: B07C 5/342 according to optical properties, e.g. colour according to radiation transmittivity B07C5/3416
• CPC Class Codes: G07D 7/004 using digital security elements, e.g. information coded on a magnetic thread or strip
• CPC Class Codes: G07D 7/1205 Testing spectral properties
• CPC Class Codes: G07D 7/121 Apparatus characterised by sensor details
• CPC Class Codes: G07D 7/17 Apparatus characterised by positioning means or by means responsive to positioning

Abstract

A method and a system are disclosed for processing a banknote. The method includes providing a banknote having at least one photonically active security feature, the banknote being moved along a conveyance path; illuminating the at least one security feature with light from a stimulus source; identifying a location of the at least one security feature by detecting an emission from the security feature; directing an excitation source at the identified location; illuminating the at least security feature with light from the excitation source; and detecting a further emission from the photonically active security feature in response to the light from the excitation source. The step of identifying may include operating a linescan camera having scan axis that is parallel to a conveyance axis, or a scan axis that is perpendicular to the conveyance axis. The step of identifying may also include operating a single element detector to accumulate a line scan along the banknote at a same cross-axis location as a field of view of the excitation source. In one embodiment the step of directing includes delaying operation of the excitation source for a period of time that is a function of at least a speed of conveyance, and a distance between a illumination points of the stimulus source and the excitation source. The photonically active security feature can include at least one thread or planchette or other structure, such as a tape, having a substrate material and an electromagnetic radiation emitting and amplifying material for providing a laser-like emission. The structure can be embedded within or disposed on the banknote. The detected further emission may be an optical code for identifying at least one characteristic of the banknote.

Claims

1. A method for processing a banknote, comprising:

providing a banknote having at least one photonically active security feature, the banknote being moved along a conveyance path;

illuminating the at least one security feature with light from a stimulus source;

identifying a location of the at least one security feature by detecting an emission from the security feature;

directing an excitation source at the identified location;

illuminating the at least security feature with light from the excitation source; and

detecting a further emission from the photonically active security feature in response to the light from the excitation source.

2. A method as in claim 1, wherein the step of identifying includes operating a linescan camera having scan axis that is parallel to a conveyance axis.

3. A method as in claim 1, wherein the step of identifying includes operating a linescan camera having scan axis that is perpendicular to a conveyance axis.

4. A method as in claim 1, wherein the step of identifying includes operating a single element detector to accumulate a line scan along the banknote at a same cross-axis location as a field of view of the excitation source.

5. A method as in claim 1, wherein the step of directing includes delaying operation of the excitation source for a period of time that is a function of at least a speed of conveyance, and a distance between a illumination points of the stimulus source and the excitation source.

6. A method as in claim 1, wherein the photonically active security feature is comprised of at least one thread comprising a substrate material and an electromagnetic radiation emitting and amplifying material for providing a laser-like emission.

7. A method as in claim 1, wherein the photonically active security feature is comprised of at least one planchette comprising a substrate material and an electromagnetic radiation emitting and amplifying material for providing a laser-like emission.

8. A method as in claim 1, wherein the photonically active security feature is comprised of at least one structure embedded within or disposed on the banknote, the structure comprising a substrate material and an electromagnetic radiation emitting and amplifying material for providing a laser-like emission.

9. A method as in claim 1, wherein the detected further emission is comprised of an optical code for identifying at least one characteristic of the banknote.

10. A system for processing a banknote, comprising:

a conveyance for moving a banknote having at least one photonically active security feature along a conveyance path;

a stimulus source for illuminating the at least one security feature with light;

a first detector for detecting an emission from the security feature in response to light from the stimulus source;

an excitation source disposed for illuminating the at least security feature;

means coupled to the detector for identifying a location of the at least one security feature and for directing the excitation source at the identified location; and

a second detector for detecting a further emission from the photonically active security feature in response to light from the excitation source.

11. A system as in claim 10, wherein the identifying means comprises a linescan camera having scan axis that is parallel to a conveyance axis.

12. A system as in claim 10, wherein the identifying means comprises a linescan camera having scan axis that is perpendicular to a conveyance axis.

13. A system as in claim 10, wherein the identifying means comprises a single element detector operating to accumulate a line scan along the banknote at a same cross-axis location as a field of view of the excitation source.

14. A system as in claim 10, wherein the identifying means delays operation of the excitation source for a period of time that is a function of at least a speed of conveyance, and a distance between a illumination points of the stimulus source and the excitation source.

15. A system as in claim 10, wherein the photonically active security feature is comprised of at least one thread comprising a substrate material and an electromagnetic radiation emitting and amplifying material for providing a laser-like emission.

16. A system as in claim 10, wherein the photonically active security feature is comprised of at least one planchette comprising a substrate material and an electromagnetic radiation emitting and amplifying material for providing a laser-like emission.

17. A system as in claim 10, wherein the photonically active security feature is comprised of at least one structure embedded within or disposed on the banknote, the structure comprising a substrate material and an electromagnetic radiation emitting and amplifying material for providing a laser-like emission.

18. A system as in claim 10, wherein the further emission is comprised of an optical code for identifying at least one characteristic of the banknote.