Paper sheet authentication apparatus

• US 10,176,659 B2
• Filed: 09/30/2013
• Issued: 01/08/2019
• Est. Priority Date: 09/30/2013
• Status: Active Grant

• Current Assignee: Glory Limited
• Original Assignee: Glory Limited
• Inventors: Yamaguchi, Yoshiki, Sato, Takeshi
• Primary Examiner(s): Porta, David
• Assistant Examiner(s): Faye, Mamadou
• Application Number:
  US15/021,882
• Publication Number:
  US 20160225215A1
• Time in Patent Office: 1,926 Days
• CPC Class Codes: G07D 7/005 Testing security markings invisible to the naked eye, e.g. verifying thickened lines or unobtrusive markings or alterations
• CPC Class Codes: G07D 7/1205 Testing spectral properties
• CPC Class Codes: G07D 7/121 Apparatus characterised by sensor details

Abstract

A paper sheet authentication apparatus determines the type of the paper sheet by using a characteristic other than a fluorescent light characteristic, sequentially emits excitation lights of different wavelengths on the paper sheet, measures an intensity of light per wavelength within a predetermined range emitted by a fluorescent material applied to the paper sheet, and acquires fluorescent light characteristic data as the result. The paper sheet authentication apparatus performs the authentication of the paper sheet by using fluorescent light characteristic data of a genuine paper sheet previously stored per type of the paper sheet or a threshold calculated therefrom and the acquired fluorescent light characteristic data.

Claims

1. A paper sheet authentication apparatus that authenticates a paper sheet to which a fluorescent material is applied, comprising:

a type determination unit that determines a type of the paper sheet;

an excitation-light light source that emits a plurality of excitation lights, one by one, to the paper sheet, each excitation light having a different wavelength;

a plurality of filters each passes light of only a different wavelength band among light emitted by the fluorescent material excited by the excitation light;

a plurality of light receivers that receive the light passed by the plurality of filters;

a fluorescent light characteristic data generating unit that generates fluorescent light characteristic data based on an intensity of the light received by the plurality of light receivers when the excitation light is emitted by the excitation-light light source;

a storage unit that previously stores therein data of a genuine paper sheet; and

an authentication unit that authenticates the paper sheet by using the of the genuine paper sheet corresponding to the type of the paper sheet determined by the type determination unit and the fluorescent light characteristic data generated by the fluorescent light characteristic data generating unit,

wherein

the plurality of filters include a first filter and a second filter, and the plurality of light receivers include a first receiver and a second receiver, and

the first filter is overlapped on both the first receiver and the second receiver, and the second filter is overlapped on the second receiver.

2. The paper sheet authentication apparatus according to claim 1, wherein the excitation-light light source, the plurality of filters, and the plurality of light receivers are all arranged on one surface side of the paper sheet.

3. The paper sheet authentication apparatus according to claim 1, wherein the excitation-light light source is arranged on one surface side of the paper sheet, and the plurality of filters and the plurality of light receivers are arranged on the other surface side of the paper sheet.

4. The paper sheet authentication apparatus according to claim 1, wherein

while the excitation-light light source emits one excitation light to the paper sheet, the intensity of the light that has been received by each of the plurality of light receivers is acquired sequentially or acquired at the same time.

5. The paper sheet authentication apparatus according to claim 4, wherein

the excitation-light light source periodically and sequentially emits the plurality of excitation lights of different wavelengths,

the plurality of light receivers periodically and sequentially receive light of one wavelength band at a time, and

the fluorescent light characteristic data generating unit generates the fluorescent light characteristic data respectively based on the intensity of light received by each of the plurality of light receivers.

6. The paper sheet authentication apparatus according to claim 1, wherein

the fluorescent light characteristic data generating unit generates a matrix of an excitation light wavelengths and light receiving wavelength bands, each excitation light wavelength corresponding to a wavelength of each excitation light and each light receiving wavelength band corresponding to a wavelength band of the light received by each light receiver,

the fluorescent light characteristic data generating unit generates the fluorescent light characteristic for each domain of the matrix,

the storage unit stores therein a domain of the matrix to be used by the authentication unit, per type of the paper sheet, and

the authentication unit performs the authentication by using the fluorescent light characteristic data of the domain of the matrix corresponding to the type of the paper sheet determined by the type determination unit.

7. The paper sheet authentication apparatus according to claim 1, wherein

the authentication unit determines that light of a corresponding wavelength band has been received when the intensity of the light received by the plurality of light receivers is a specified value or more, and determines that the light of the corresponding wavelength band has not been received when the intensity of the light received by the plurality of light receivers is less than the specified value.

8. The paper sheet authentication apparatus according to claim 1, further comprising an optical image acquisition unit that acquires an optical image of the paper sheet, wherein

the type determination unit determines the type of the paper sheet by using image data of a predetermined area of the paper sheet acquired, by the optical image acquisition unit, while the paper sheet is being transported.

9. The paper sheet authentication apparatus according to claim 1, wherein

the plurality of light receivers measure the intensity of the light emitted by the fluorescent material of the sheet being transported, and

the fluorescent light characteristic data generating unit generates the fluorescent light characteristic data based on the intensity of the light measured by the plurality of light receivers at a predetermined area of the paper sheet.

10. The paper sheet authentication apparatus according to claim 1, wherein

the plurality of light receivers receive the light passed by the plurality of filters while the excitation light is emitted by the excitation-light light source, and receive the light passed by the plurality of filters after the excitation-light light source is turned off as phosphorescent light,

the fluorescent light characteristic data generating unit further generates phosphorescent light characteristic data based on the intensity of the phosphorescent light,

the storage unit storing therein data on the phosphorescent light of the genuine paper sheet, and

the authentication unit determines, based on the type of the paper sheet determined by the type determination unit, authenticity of the paper sheet by using at least one of the fluorescent light characteristic data and the phosphorescent light characteristic data generated by the fluorescent light characteristic data generating unit, and corresponding data of the genuine paper sheet.

11. The paper sheet authentication apparatus according to claim 1, wherein

the excitation-light light source emits excitation lights having different wavelengths in a visible light band, and

the plurality of filters each passes light having a different wavelength in an infrared light band.

12. The paper sheet authentication apparatus according to claim 1, wherein

the excitation-light light source emits excitation lights having different wavelengths in an infrared light band, and

the plurality of filters each passes pass light having a different wavelength in an infrared light band.

13. The paper sheet authentication apparatus according to claim 1, wherein

the plurality of filters further includes a third filter,

the plurality of light receivers further includes a third receiver and a fourth receiver,

the first filter is overlapped on the first receiver, the second receiver and the third receiver,

the second filter is overlapped on the second receiver and the third receiver and

the third filter is overlapped on the third receiver.

14. The paper sheet authentication apparatus according to claim 1, wherein the fluorescent light characteristic data generating unit is configured to correct, based on physical positions of the plurality of light receivers and a transport speed of the paper sheet, a time difference in data acquired from the plurality of light receivers caused from the difference of physical positions of the plurality of the light receivers with respect to a transport direction of the paper sheet.

15. The paper sheet authentication apparatus according to claim 13, wherein the four light receivers are arranged in a two-by-two matrix.