Optical filtration for underwater viewing, photography, and the like
Abstract
Abstract The present invention provides selective color filtration devices for underwater viewing or photography, including the provision of a predetermined color-selective light-filtering coating on a light source used for underwater viewing or photography designed, for example, to absorb light in the bluegreen end of the visible spectrum and to pass the red, orange and yellow wavelengths, in accordance with a predetermined formula, so as to correct to some extent the filtering effect caused by the water and by the particles suspended in the water. When the teachings of the present invention are followed, underwater objects may be photographed in colors more natural than those heretofore possible, and without the usual bluishgreenish tinge which such objects are normally photographed by present day equipment.
Inventors
- 👤 David N Bush Jr
Bibliographic Details
Claims Analysis
Total Claims: 1References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-22 | 1974-09-21 | 1975-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-22 | 1978-09-21 | 1979-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-22 | 1982-09-21 | 1983-03-23 | $7700.00 | Window Closed / Lapsed |