DE702967C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Method for recording and playing back optical sound recordings
Assignee: Individual
•
Filing: 1938-03-15
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Granted: 1941-02-20
•
Expires: 1958-03-15
Abstract
No abstract record available.
Inventors
- 👤 Ernst Bergmann
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-11-02 11:40
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09; G11B7/0938; G11B7/002; G11B7/0037; G11B7/007
Claims Analysis
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References Cited (Backward Citations)
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