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Application filed by Ritzerfeld GerhardfiledCriticalRitzerfeld Gerhard
Publication of DK333674ApublicationCriticalpatent/DK333674A/da
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
G03B21/132—Overhead projectors, i.e. capable of projecting hand-writing or drawing during action
G—PHYSICS
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
G03B21/14—Details
G03B21/20—Lamp housings
G03B21/2006—Lamp housings characterised by the light source
G03B21/2013—Plural light sources
Landscapes
Physics & Mathematics
(AREA)
General Physics & Mathematics
(AREA)
Projection Apparatus
(AREA)
Non-Portable Lighting Devices Or Systems Thereof
(AREA)