GB646520A - Improvements in and relating to area measuring apparatus - Google Patents

Improvements in and relating to area measuring apparatus

Info

Publication number
GB646520A
GB646520A GB621848A GB621848A GB646520A GB 646520 A GB646520 A GB 646520A GB 621848 A GB621848 A GB 621848A GB 621848 A GB621848 A GB 621848A GB 646520 A GB646520 A GB 646520A
Authority
GB
United Kingdom
Prior art keywords
photo
cell
illuminated
lamps
relating
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
GB621848A
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.)
Londex Ltd
Original Assignee
Londex 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 Londex Ltd filed Critical Londex Ltd
Priority to GB621848A priority Critical patent/GB646520A/en
Publication of GB646520A publication Critical patent/GB646520A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/28—Measuring arrangements characterised by the use of optical techniques for measuring areas

Landscapes

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

Abstract

646,520. Measuring areas photo-electrically. LONDEX, Ltd., and BESSON, A. P. Feb. 28, 1948, No. 6218. [Class 40 (iii)] [Also in Group XL (a)] In a system for measuring the area of an opaque sheet 21 by causing it to obstruct light falling on a photo-cell 12 from an illuminated surface, e.g. a translucent plate 1, the lamps 3 by which the surface is illuminated are arranged in a circle of similar diameter to the surface so that light from a unit area taken anywhere on the surface produces the same effect at the photo-cell. Preferably the lights of a flickering nature and as shown, single coil gas-filled lamps are energized in two groups via differentially wound primaries of a transformer. If either group fails a lamp 9 connected to the secondary glows.
GB621848A 1948-02-28 1948-02-28 Improvements in and relating to area measuring apparatus Expired GB646520A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB621848A GB646520A (en) 1948-02-28 1948-02-28 Improvements in and relating to area measuring apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB621848A GB646520A (en) 1948-02-28 1948-02-28 Improvements in and relating to area measuring apparatus

Publications (1)

Publication Number Publication Date
GB646520A true GB646520A (en) 1950-11-22

Family

ID=9810558

Family Applications (1)

Application Number Title Priority Date Filing Date
GB621848A Expired GB646520A (en) 1948-02-28 1948-02-28 Improvements in and relating to area measuring apparatus

Country Status (1)

Country Link
GB (1) GB646520A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2178167A (en) * 1985-07-19 1987-02-04 Metal Box Plc Apparatus for photographic image area measurement
GB2242019A (en) * 1990-02-05 1991-09-18 Dresser Ind Photoelectric mensuration device and method for determining pdc cutter ware and area

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2178167A (en) * 1985-07-19 1987-02-04 Metal Box Plc Apparatus for photographic image area measurement
GB2178167B (en) * 1985-07-19 1989-07-19 Metal Box Plc Apparatus for photographic image area measurement
GB2242019A (en) * 1990-02-05 1991-09-18 Dresser Ind Photoelectric mensuration device and method for determining pdc cutter ware and area
GB2242019B (en) * 1990-02-05 1993-12-08 Dresser Ind Photoelectric mensuration device and method for determining PDC cutter wear

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