GB638141A - Projection screen - Google Patents
Projection screenInfo
- Publication number
- GB638141A GB638141A GB29639/46A GB2963946A GB638141A GB 638141 A GB638141 A GB 638141A GB 29639/46 A GB29639/46 A GB 29639/46A GB 2963946 A GB2963946 A GB 2963946A GB 638141 A GB638141 A GB 638141A
- Authority
- GB
- United Kingdom
- Prior art keywords
- elements
- row
- screen
- tool
- oct
- 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
Links
Classifications
-
- 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
- G03B21/54—Accessories
- G03B21/56—Projection screens
- G03B21/60—Projection screens characterised by the nature of the surface
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optical Elements Other Than Lenses (AREA)
Abstract
638,141. Projection screens. PHILCO CORPORATION. Oct. 4, 1946, No. 29639. Convention date, Oct. 5, 1945. [Class 97 (i)] The reflective surface of a projection screen comprises several specularly reflecting elements of such small size as to be beyond the visual resolving power of an observer at the minimum proper viewing distance, the elements being arranged in contiguous relationship and each element being so shaped that the curves of intersection of its surface with planes which are perpendicular to the general plane of the screen and to an axis of symmetry of the element, are cycloids. The elements which may be elongated in form may be arranged in parallel rows and an element of one row may be arranged in staggered relation to the adjacent element of the adjacent row. In one manner of manufacturing the screen, a row of elements is formed by feeding a sheet 1 of suitable material, e.g. wax, at a uniform rate beneath the circular edge of a cutting tool 6 which is rotated about an axis substantially parallel to the plane of the material in a direction opposite to that in which the material is being moved. The next row of elements is formed in the same manner after the tool has been moved relatively to the work material by an indexing machine. The matrix so formed may be provided with a suitable reflective surface to form a screen directly or from this matrix a press tool or die may be made for the production of screens as by stamping or moulding.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US638141XA | 1945-10-05 | 1945-10-05 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB638141A true GB638141A (en) | 1950-05-31 |
Family
ID=22051666
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB29639/46A Expired GB638141A (en) | 1945-10-05 | 1946-10-04 | Projection screen |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB638141A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2005059640A1 (en) * | 2003-12-17 | 2005-06-30 | Harry Kurt Hahn | Viewing screen |
-
1946
- 1946-10-04 GB GB29639/46A patent/GB638141A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2005059640A1 (en) * | 2003-12-17 | 2005-06-30 | Harry Kurt Hahn | Viewing screen |
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