{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-9736355","patent":{"patent_number":"US-9736355","title":"Phase difference calibration in a variable focal length lens system","assignee":null,"inventors":[],"filing_date":"2016-05-03T00:00:00.000Z","publication_date":"2017-08-15T00:00:00.000Z","cpc_codes":["H04N","H04N","G02F"],"num_claims":20,"abstract":"A variable focal length (VFL) lens system is utilized to determine surface Z-height measurements of imaged surfaces. A controller of the system is configured to control a VFL lens (e.g., a tunable acoustic gradient index of refraction lens) to periodically modulate its optical power and thereby periodically modulate a focus position at a first operating frequency, wherein the periodically modulated VFL lens optical power defines a first periodic modulation phase. A phase timing signal is synchronized with a periodic signal in the controller that has the first operating frequency and that has a second periodic modulation phase that has a phase offset relative to the first periodic modulation phase. A phase offset compensating portion is configured to perform a phase offset compensating process that provides Z-height measurements, wherein at least one of Z-height errors or Z-height variations that are related to a phase offset contribution are at least partially eliminated."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Phase difference calibration in a variable focal length lens system","description":"A variable focal length (VFL) lens system is utilized to determine surface Z-height measurements of imaged surfaces. A controller of the system is configured to control a VFL lens (e.g., a tunable aco","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-9736355","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-9736355","citation_suggestion":"Patentable. \"Phase difference calibration in a variable focal length lens system\" (US-9736355). https://patentable.app/patents/US-9736355","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-9736355","json":"https://patentable.app/api/llm-context/US-9736355","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-06-06T08:19:26.191Z"}