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.)
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.)
Landis and Gyr AG
Original Assignee
Landis and Gyr AG
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 Landis and Gyr AGfiledCriticalLandis and Gyr AG
Publication of FR2410839A1publicationCriticalpatent/FR2410839A1/fr
Application grantedgrantedCritical
Publication of FR2410839B3publicationCriticalpatent/FR2410839B3/fr
G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
G03B—APPARATUS 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
G03B21/00—Projectors or projection-type viewers; Accessories therefor
G03B21/54—Accessories
G03B21/56—Projection screens
G03B21/58—Projection screens collapsible, e.g. foldable; of variable area
Landscapes
Physics & Mathematics
(AREA)
General Physics & Mathematics
(AREA)
Overhead Projectors And Projection Screens
(AREA)
Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes
(AREA)
Transmission Devices
(AREA)
Projection Apparatus
(AREA)
FR7833726A1977-12-011978-11-29Dispositif permettant de deformer une plaque initialement plane pour produire une surface cintree en arc cylindrique de revolution
GrantedFR2410839A1
(fr)