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:
Jan. 07, 1997
Filed:
Nov. 02, 1994
Shih-Lai Lu, Taipei, TW;
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
Optical security articles and methods of making same are described comprising a first layer substantially transparent to visible light and having a first refractive index, the first layer having a relief pattern on a first surface thereof and a substantially smooth second surface, and an adhesive layer coterminating with the first layer. The adhesive layer substantially completely fills and makes contact with a first portion of the plurality of geometric concavities, the adhesive layer having a second refractive index which is substantially similar to the first refractive index of the first layer. A second portion of the plurality of geometric concavities are precluded from contact with the adhesive layer by a corresponding plurality of separation layers, each separation layer having a separation layer refractive index which is different from the refractive index of the first layer.