GB606010A - Improvements in optical projection screens - Google Patents

Improvements in optical projection screens

Info

Publication number
GB606010A
GB606010A GB834646A GB834646A GB606010A GB 606010 A GB606010 A GB 606010A GB 834646 A GB834646 A GB 834646A GB 834646 A GB834646 A GB 834646A GB 606010 A GB606010 A GB 606010A
Authority
GB
Grant status
Application
Patent type
Prior art keywords
fresnel lens
projection screens
improvements
optical projection
march
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
GB834646A
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.)
BAE Systems Electronics Ltd
Marconis Wireless Telegraph Co Ltd
Original Assignee
BAE Systems Electronics Ltd
Marconis Wireless Telegraph 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

Links

Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ELECTROGRAPHY; HOLOGRAPHY
    • G03BAPPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00Projectors or projection-type viewers; Accessories therefor
    • G03B21/54Accessories
    • G03B21/56Projection screens
    • G03B21/60Projection screens characterised by the nature of the surface
    • G03B21/62Translucent screens
    • G03B21/625Lenticular translucent screens

Abstract

606,010. Projection screens. MARCONI'S WIRELESS TELEGRAPH CO., Ltd. March 18, 1946, No. 8346. Convention date, March 17, 1945. [Class 97 (i)] A back projection screen is formed with a series of prismatic grooves 3, forming a Fresnel lens, on the back and a series of cylindrical ribs 4 on the front, with a diffusing layer 2, for example of gelatin, between. The diffusing layer may be provided by forming the Fresnel lens and the ribs 4 on a single opalescent sheet. The grooves of the Fresnel lens may be concentric and circular or in a continuous spiral.
GB834646A 1945-03-17 1946-03-18 Improvements in optical projection screens Expired GB606010A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US606010X true 1945-03-17 1945-03-17

Publications (1)

Publication Number Publication Date
GB606010A true true GB606010A (en) 1948-08-04

Family

ID=22030546

Family Applications (1)

Application Number Title Priority Date Filing Date
GB834646A Expired GB606010A (en) 1945-03-17 1946-03-18 Improvements in optical projection screens

Country Status (1)

Country Link
GB (1) GB606010A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4616217A (en) * 1981-05-22 1986-10-07 The Marconi Company Limited Visual simulators, computer generated imagery, and display systems
GB2436498A (en) * 2005-07-09 2007-09-26 Ncast Ltd Rear projection screen

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4616217A (en) * 1981-05-22 1986-10-07 The Marconi Company Limited Visual simulators, computer generated imagery, and display systems
GB2436498A (en) * 2005-07-09 2007-09-26 Ncast Ltd Rear projection screen
GB2436498B (en) * 2005-07-09 2009-01-07 Ncast Ltd Rear projection screen

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