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:
May. 09, 2000
Filed:
Jul. 28, 1998
NHK Spring Co., Ltd., , JP;
Abstract
Provided is an economical identification system suitable for use on commercial products which is difficult to duplicate, and highly identifiable. The system includes an identification medium having a high-polymer cholesteric liquid crystal material applied thereon. The high-polymer cholesteric liquid crystals selectively reflect a certain wavelength, and this wavelength changes with the change in the incident angle of the light. The liquid crystals also have the property to circularly polarize the reflected light in either sense. By taking advantages of such properties, it is possible to provide a highly identifiable structure which, however, is highly difficult to illicitly duplicate. In particular, by forming the reflective layer of a hologram with high-polymer cholesteric liquid crystals, the hologram can be used as an identification medium which is highly difficult to duplicate but easy to identify with a machine.