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:
Mar. 17, 2015
Filed:
Aug. 17, 2012
Charles Neugebauer, Los Altos, CA (US);
William Saperstein, San Carlos, CA (US);
Charles Neugebauer, Los Altos, CA (US);
William Saperstein, San Carlos, CA (US);
barnesandnoble.com llc, New York, NY (US);
Abstract
A system for illuminating a reflective display or other material from a planar front device and a method of manufacture thereof. The system includes a light guide plate that conducts light from an edge light source across the face of a reflective display. Micro scattering features are formed on an outer surface of the light guide, farthest from the reflective display or material. A stepped index layer is formed on the surface of light guide plate containing the micro scattering features. The stepped index layer has an index of refraction lower than an index of refraction of the light guide plate to assist in the total internal reflection of light injected into the light guide plate. The micro scattering features, light reflecting areas, redirect luminous flux toward the display. In one embodiment, the micro scattering features are formed as white dots on the light guide plate. A black absorbing layer can be added to each white scattering dot in order to improve the apparent contrast when the front light is deactivated.