{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-11470291","patent":{"patent_number":"US-11470291","title":"Projector and focal length adjusting method thereof","assignee":null,"inventors":[],"filing_date":"2020-01-08T00:00:00.000Z","publication_date":"2022-10-11T00:00:00.000Z","cpc_codes":["H04N","H04N","H04N"],"num_claims":14,"abstract":"A projector including a casing, a control system, an image assembly and at least one electric thermal heater is provided. The image assembly is coupled to and controlled by the control system. The electric thermal heater is coupled to and controlled by the control system. The control system is configured to activate the electric thermal heater to preheat the image assembly, such that the image assembly is warmed up to a cut-off temperature. Then, the control system is configured to switch off the electric thermal heater. Then the focal length of the image assembly is adjusted. A focal length adjusting method for the projector is further provided. The projector and the method may be used to avoid the thermal expansion of various elements, so as to avoid focal length shift."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Projector and focal length adjusting method thereof","description":"A projector including a casing, a control system, an image assembly and at least one electric thermal heater is provided. The image assembly is coupled to and controlled by the control system. The ele","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-11470291","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-11470291","citation_suggestion":"Patentable. \"Projector and focal length adjusting method thereof\" (US-11470291). https://patentable.app/patents/US-11470291","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-11470291","json":"https://patentable.app/api/llm-context/US-11470291","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-05-30T17:39:16.929Z"}