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. 03, 1990
Filed:
May. 20, 1988
John C Nelson, Santa Rosa, CA (US);
Mark E Gardiner, Santa Rosa, CA (US);
Roger H Appeldorn, White Bear Lake, MN (US);
Timothy L Hoopman, River Falls, WI (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
The present invention provides a retroreflective material which is efficient at high angles of incidence and which may be individually tailored so as to distribute light retroreflected by the material into a desired pattern or divergence profile. The retroreflective material of the present invention comprises a transparent surface layer having a front side and a back side and an array of cube corner reflective elements, each of the reflecting elements including a rectangular base on the back side of the surface layer, two rectangular faces nearly perpendicular to each other each one being joined to an edge of the rectangular base to form a reflecting element having a triangular cross section, and two triangular faces that are approximately parallel to each other and approximately perpendicular to the rectangular faces, and forming the ends of the reflecting elements; and the triangular and rectangular faces defining a pair of approximate cube corners therebetween, the reflecting elements arranged with their bases adjacent to the surface layer. The terms 'approximately parallel' and 'approximately perpendicular' are used herein to refer to faces which are truly parallel or perpendicular and faces which have small variations from true parallelism or perpendicularity.