Transparency viewing apparatus
US6119380A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 17, 1997 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | Dec 17, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/026
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A transparency viewing device comprising: at least one interior reflective surface; a light transmitting viewing surface adapted to accommodate a transparency to be viewed; a light source which provides backlight illumination to the viewing surface, thereby creating a viewing field having a transparency-bearing region; at least one masking element mounted and configured for movement with respect to the viewing surface, which masks an adjustable area of the viewing field leaving a field of view including at least part of the transparency bearing region unmasked; and at least one reflective element, additional to the interior reflective surface, attached to the masking element such that when the masking element moves the reflective element moves together with the masking element and which reflective element directs at least part of the light from the masked area to the field of view in an amount and in a direction such that the backlighting of the unmasked region is substantially changed as a function of the movement of the masking element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.