The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 16, 2002
Filed:
Oct. 31, 2000
Jock D. Mackinlay, Palo Alto, CA (US);
Daniel G. Bobrow, Palo Alto, CA (US);
Daniel H. Greene, Sunnyvale, CA (US);
L. Charles Hebel, Cupertino, CA (US);
Nicholas K. Sheridon, Los Altos, CA (US);
Craig A. Smith, Pittsford, NY (US);
William C. Emerson, Rochester, NY (US);
Xerox Corporation, Stamford, CT (US);
Abstract
Tamper-evident electric paper is made of two sheets of electric paper bonded together, the bottom sheet of which includes a pattern. Any attempt to erase a writing on the top sheet of electric paper results in the pattern on the bottom sheet of electric paper being erased. Therefore any tampering by erasure of a writing on the tamper-evident electric paper is revealed by the absence of a portion of the pattern on the bottom sheet of electric paper. Single sheet tamper-evident electric paper has a complex pattern, such as an encryption, printed on a single sheet of electric paper. Any attempt to erase a writing on the electric paper also erases a portion of the encryption, thereby providing evidence of tampering.