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Ernst Leitz Wetzlar GmbH
Original Assignee
Ernst Leitz Wetzlar GmbH
Ernst Leitz GmbH
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Application filed by Ernst Leitz Wetzlar GmbH, Ernst Leitz GmbHfiledCriticalErnst Leitz Wetzlar GmbH
Application grantedgrantedCritical
Publication of FR872980ApublicationCriticalpatent/FR872980A/fr
G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
G01J1/00—Photometry, e.g. photographic exposure meter
G01J1/10—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void
G01J1/12—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void using wholly visual means
G01J1/14—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void using wholly visual means using comparison with a surface of graded brightness
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Physics & Mathematics
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FR872980D1940-06-111941-06-10Dispositif pour la mesure du temps de pose dans la photographie
ExpiredFR872980A
(fr)
Procédé de mesure de l'éclairement, et dispositif pour sa mise en application, enparticulier en vue de l'appréciation des temps de pose en photographie