IP Library › Granted Patent US 4,367,648
Granted Patent Utility
US 4,367,648 · App. 06/245,547

Dark field viewing apparatus

Inventors: David Alexander James Sinclair, Ian R. Smith
Patented Case View Patent ↗
Granted: Jan 11, 1983 Filed: Mar 19, 1981
Inventors
David Alexander James Sinclair
Ian R. Smith
Assignee (at issue)
NATIONAL RESEARCH DEVELOPMENT CORPORATION

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Quick Facts
Patent No.
US 4,367,648
App. No.
06/245,547
Filed
1981-03-19
Granted
1983-01-11
Kind
A