Sheet identifying device

• US 8,300,217 B1
• Filed: 05/07/2012
• Issued: 10/30/2012
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Universal Entertainment Corporation
• Original Assignee: Universal Entertainment Corporation
• Inventors: Fujimoto, Jun, Nonaka, Nobuyuki, Nireki, Takao
• Primary Examiner(s): Punnoose, Roy M
• Application Number:
  US13/465,610
• Publication Number:
  US 20120268729A1
• Time in Patent Office: 176 Days
• Field of Search: 356/71, 382/135
• US Class Current: 356/71
• CPC Class Codes: G07D 7/12 Visible light, infrared or ultraviolet radiation
• CPC Class Codes: G07D 7/205 Matching spectral properties

Abstract

A sheet identifying device comprising a light-receiving section (26) for reading each pixel on a sheet which involves color information including a brightness, has a predetermined size, and is handled as one unit, a RAM (114) for storing image data constructed of read pixels, a pixel data increasing/decreasing section (116a) for increasing/decreasing the number of pixels of the image data, and a judging section for judging authentication of the sheet on the basis of the increased/decreased image data.

Claims

1. A sheet identifying device which enables judgment of authentication utilizing a microprint formed on a sheet, the microprint being constituted by forming a number of thin lines in a unit width in order to prevent counterfeit, comprising:

a reader for reading a sheet in pixels, a respective one of which includes color information having brightness, a predetermined size of which is defined as one unit;

a storage section for storing image data made up of the plurality of pixels read by means of the reader;

an increasing/decreasing section for acquiring coarsened moiré

fringes of the thin lines adjacent on the sheet by increasing or decreasing the number of pixels in the image data; and

a sheet identifying section for identifying authentication of the sheet, based upon moiré

data has the acquired moiré

fringes among of the image data increased/decreased by means of the increasing/decreasing section.

2. The sheet identifying device according to claim 1, wherein the number of pixels is increased/decreased by means of the increasing/decreasing section at a ratio different from another one in a sheet acquisition direction and in a direction orthogonal thereto.

3. The sheet identifying device according to claim 1, comprising a parameter setting section for setting an increasing/decreasing ratio so that increasing/decreasing the number of pixels by means of the increasing/decreasing section is executed at a predetermined increasing/decreasing ratio in the sheet acquisition direction and in the direction orthogonal thereto.

4. The sheet identifying device according to claim 1, the increasing/decreasing section configured to increasing/decreasing a number of pixels in the image data to increase a gap for reading a pixel to be at least as large as a gap between adjacent lines on the sheet.