GB623656A - Improvements in and relating to apparatus for screen brightness measurement - Google Patents

Improvements in and relating to apparatus for screen brightness measurement

Info

Publication number
GB623656A
GB623656A GB7467/47A GB746747A GB623656A GB 623656 A GB623656 A GB 623656A GB 7467/47 A GB7467/47 A GB 7467/47A GB 746747 A GB746747 A GB 746747A GB 623656 A GB623656 A GB 623656A
Authority
GB
United Kingdom
Prior art keywords
handle
relating
screen
auditorium
grille
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB7467/47A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
British Thomson Houston Co Ltd
Original Assignee
British Thomson Houston Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by British Thomson Houston Co Ltd filed Critical British Thomson Houston Co Ltd
Publication of GB623656A publication Critical patent/GB623656A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • 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
    • G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Photometry And Measurement Of Optical Pulse Characteristics (AREA)

Abstract

623,656. Measuring brightness photo-electrically. BRITISH THOMSON-HOUSTON CO., Ltd. March 18, 1947, No. 7467. Convention date, March 18, 1946. [Class 40 (iii)] To determine the brightness of a cinematograph screen as viewed from any direction in the auditorium a tube 7 mounted on a handle 6 is held by the operator with one end 28 in contact with the screen, the angle of the tube being adjusted by a rotatable part 20 and gearing 17, 18, and being indicated by a ray of light from a source 10 reflected from a mirror 11 through lenses 12 and 13 to some point in the auditorium. A photo-cell 14 mounted inside a grille 28 through which light must pass perpendicularly to the grille operates a meter 21 mounted on the handle. A battery 25 and switch 23 are also mounted on the handle.
GB7467/47A 1946-03-18 1947-03-18 Improvements in and relating to apparatus for screen brightness measurement Expired GB623656A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US623656XA 1946-03-18 1946-03-18

Publications (1)

Publication Number Publication Date
GB623656A true GB623656A (en) 1949-05-20

Family

ID=22042002

Family Applications (1)

Application Number Title Priority Date Filing Date
GB7467/47A Expired GB623656A (en) 1946-03-18 1947-03-18 Improvements in and relating to apparatus for screen brightness measurement

Country Status (1)

Country Link
GB (1) GB623656A (en)

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