{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-10488228","patent":{"patent_number":"US-10488228","title":"Transparent-block encoder head with isotropic wedged elements","assignee":null,"inventors":[],"filing_date":"2018-01-10T00:00:00.000Z","publication_date":"2019-11-26T00:00:00.000Z","cpc_codes":["G01D","G01D","G01D","H01L"],"num_claims":33,"abstract":"An encoder head configured for use with a lithographic exposure tool. The head is devoid of a multiplicity of stand-alone optical retroreflectors. The head includes a single, geometrically substantially perfect optically-isotropic cuboid complemented with optically-isotropic prismatic elements to form a contraption that, in combination with a diffraction grating disposed on a wafer-stage of the exposure tool, splits a single input beam of light delivered to the contraption into four measurement (sub-)beams of light (two in xz-plane, two in yz-plane) and causes each of these sub-beams traverse two prismatic elements and be retro-reflected internally within the cuboid to exit the encoder head at a non-zero angle with respect to the input beam of light, thereby solving problems of (i) structural complexity of a conventional encoder head for use in an exposure tool, (ii) burdensome alignment of the multitude of optical prisms in the process of forming such encoder head, and (iii) cyclic non-linear errors associated with measurements involving conventional corner-cubes-based encoder heads while, at the same time, reducing the geometrical footprint of the encoder head (without reducing the cross-section of the single input beam)."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Transparent-block encoder head with isotropic wedged elements","description":"An encoder head configured for use with a lithographic exposure tool. The head is devoid of a multiplicity of stand-alone optical retroreflectors. The head includes a single, geometrically substantial","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-10488228","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-10488228","citation_suggestion":"Patentable. \"Transparent-block encoder head with isotropic wedged elements\" (US-10488228). https://patentable.app/patents/US-10488228","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-10488228","json":"https://patentable.app/api/llm-context/US-10488228","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-05-31T12:36:43.553Z"}