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:
Apr. 20, 2010
Filed:
Sep. 11, 2006
Takashi Amano, Kanagawa, JP;
Tsunehisa Nakamura, Tokyo, JP;
Takashi Amano, Kanagawa, JP;
Tsunehisa Nakamura, Tokyo, JP;
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
When using an acrylic resin with a refractive index of 1.494, for example, the structure of the Fresnel lens is such that in a segment where a deviation angle of 19.5° or less is required, refraction-only prisms which do not cause any reflections are used, while in a segment where a deviation angle of 31.0° or larger is required, single-step total reflection prisms in which light is totally internally reflected once and then refracted are used and, in a segment where a deviation angle not smaller than 19.5° but not larger than 31.0° is required, two-step total reflection prisms in which light is totally internally reflected twice and then refracted are used.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile