×

Document security system

  • US 7,129,840 B2
  • Filed: 09/03/2002
  • Issued: 10/31/2006
  • Est. Priority Date: 09/03/2002
  • Status: Expired due to Fees
First Claim
Patent Images

1. A document monitoring device comprising:

  • a plurality of sensors disposed about an area of a structure suitable for placement of one or more documents, each sensor producing a sensor output signal in response to sensing a response signal produced by a document; and

    a detection module coupled to receive sensor output signals from said sensors to produce a detection signal indicative of movement of a first document disposed on said structure,wherein a first set of sensor output signals that are produced by a first set of said sensors is associated with a first position of said first document and a second set of sensor output signals that are produced by a second set of said sensors is associated with a second position of said second document,wherein said detection signal is produced based on said first set of sensors and said second set of sensors.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×