Lens-fitted photo film unit, and method of making photo-print
US6222995A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 25, 1999 |
| Grant date | Apr 24, 2001 |
| Priority date | — |
| Expiry date | Oct 25, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B2219/045
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lens-fitted photo film unit can take indoor- and night-photographs at adequate tone- and color-reproductions, by satisfying the condition: EQU -6.ltoreq.2log.sub.2 (A)+log.sub.2 (1/T)-log.sub.2 (0.3.multidot.S).ltoreq.5 wherein T, A and S represents the shutter speed, the aperture size, and the ISO film speed. The film speed is determined to be not less than ISO640, and more preferably not less than ISO1000. The guide number (ISO100.multidot.m) of a flash device of the film unit is set to be in a range from 0.1 to 8, more preferably from 1 to 6, and most preferably from 3 to 5, and satisfies the condition: 8.0.ltoreq.log.sub.2 (G.sup.2)+log.sub.2 (1/T).ltoreq.12.0, in combination with the shutter speed T.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.