{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-8494229","patent":{"patent_number":"US-8494229","title":"Device and method for determining gaze direction","assignee":null,"inventors":[],"filing_date":"2008-02-14T00:00:00.000Z","publication_date":"2013-07-23T00:00:00.000Z","cpc_codes":["G06F","A61B"],"num_claims":20,"abstract":"An eye tracker device (200) comprises a diffractive beam expander (207) to provide two substantially collimated illuminating light beams (B11, B12). The collimated light beams (B11, B12) provide two reflection spots (G1, G2) appearing in the image of the eye. The gaze direction (GZD) is calculated from the positions of the reflection spots (G1, G2) with respect to the pupil (P) of the eye (E1). The two illuminating beams (B11, B12) are provided by splitting an infrared laser beam (B4) into two in-coupled beams (B5, B6), which propagate in different directions in the substrate (7) of the beams expander. The in-coupled beams (B5, B6) are expanded and their light is subsequently coupled out of the substrate (7) by an out-coupling grating (230) to illuminate the eye (E1). The same substrate (7) may also be used to implement a virtual display device (100) for displaying virtual images to said eye (E1)."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Device and method for determining gaze direction","description":"An eye tracker device (200) comprises a diffractive beam expander (207) to provide two substantially collimated illuminating light beams (B11, B12). The collimated light beams (B11, B12) provide two r","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-8494229","license":"CC-BY-4.0-like","license_terms":"AI-generated analysis on this page (summary, layman_explanation, technical_analysis, business_analysis, faqs) may be reused with attribution and a visible link back to the canonical URL above. Patent abstracts, claims, and bibliographic data are USPTO public domain.","required_link":"https://patentable.app/patents/US-8494229","citation_suggestion":"Patentable. \"Device and method for determining gaze direction\" (US-8494229). https://patentable.app/patents/US-8494229","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-8494229","json":"https://patentable.app/api/llm-context/US-8494229","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-05-30T18:47:23.465Z"}