Educational display device and method
Abstract
Abstract AN EDUCATIONAL DISPLAY DEVICE AND METHOD OF MANUFACTURE ARE DISCLOSED INCORPORATING A NORMALLY DARK DEAD FRONT MATTE SURFACE OF PHOSOGRAPHIC FILM HAVING MULTIPLE SELECTED PATTERNS WHICH ARE REFLECTIVELY OPAQUE AND TRANSLUCENT TO A SELECTED BACKLIGHT AND WHICH ARE NORMALLY FRONTALLY VISUALLY INDISTINGUISHABLE FROM ADJOINING DARK OPAQUE BACKGROUND AREAS WHEN VIEWED UNDER LOW LEVEL REFLECTED ROOM LIGHT SUIABLE FOR READING AND WRITING AND AT A DISTANCE SUITABLE FOR CLASSROOM INSTRUCTIONAL PURPOSES. THE SELECTED PATTERN AREAS ARE DISPOSED IN REGISTRY WITH CORRESPONDING SELECTIVELY ILLUMINATABLE PATTERN FORMING CELLS SECUED BEHIND A BASE PANEL SHEET OF RIGID TRANSLUCENT LIGHT DIFFUSING MATERIAL.
Inventors
- 👤 William C Cryer
- 👤 Lee Vaughn Dively
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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