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
G03B21/60—Projection screens characterised by the nature of the surface
Landscapes
Physics & Mathematics
(AREA)
General Physics & Mathematics
(AREA)
Developing Agents For Electrophotography
(AREA)
Diaphragms For Electromechanical Transducers
(AREA)
Financial Or Insurance-Related Operations Such As Payment And Settlement
(AREA)