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. 23, 2013
Filed:
Feb. 14, 2008
Toni Järvenpää, Toijala, FI;
Tapani Levola, Tampere, FI;
Toni Järvenpää, Toijala, FI;
Tapani Levola, Tampere, FI;
Nokia Corporation, Espoo, FI;
Abstract
An eye tracker device () comprises a diffractive beam expander () to provide two substantially collimated illuminating light beams (B, B). The collimated light beams (B, B) provide two reflection spots (G, G) appearing in the image of the eye. The gaze direction (GZD) is calculated from the positions of the reflection spots (G, G) with respect to the pupil (P) of the eye (E). The two illuminating beams (B, B) are provided by splitting an infrared laser beam (B) into two in-coupled beams (B, B), which propagate in different directions in the substrate () of the beams expander. The in-coupled beams (B, B) are expanded and their light is subsequently coupled out of the substrate () by an out-coupling grating () to illuminate the eye (E). The same substrate () may also be used to implement a virtual display device () for displaying virtual images to said eye (E).