{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-8542560","patent":{"patent_number":"US-8542560","title":"Diffraction grating and optical pickup device","assignee":null,"inventors":[],"filing_date":"2006-08-17T00:00:00.000Z","publication_date":"2013-09-24T00:00:00.000Z","cpc_codes":["G11B","G11B","G11B"],"num_claims":5,"abstract":"Disclosed are a module to detect a tracking error signal that is easy to be assembled and robust against variation in a track angle, a diffraction grating, an optical pickup, and an optical disc apparatus that enable the module to be realized, wherein a diffraction grating divided into at least three areas, first, second, and third areas, is used; the second area is an area that do not diffract light; and focusing positions of light diffracted by the first and third areas sandwiching the second area therebetween on an optical disc are arranged with a spacing of (2n−1)×t/2 in an optical disc radial direction, respectively, where n is a nonnegative integer and t is a spacing of guide grooves of the optical disc."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Diffraction grating and optical pickup device","description":"Disclosed are a module to detect a tracking error signal that is easy to be assembled and robust against variation in a track angle, a diffraction grating, an optical pickup, and an optical disc appar","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-8542560","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-8542560","citation_suggestion":"Patentable. \"Diffraction grating and optical pickup device\" (US-8542560). https://patentable.app/patents/US-8542560","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-8542560","json":"https://patentable.app/api/llm-context/US-8542560","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-05-30T14:11:36.148Z"}