Method of spectrographically measuring density of photographic negative color film
US4779987A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jun 13, 1986 |
| Grant date | Oct 25, 1988 |
| Priority date | — |
| Expiry date | Jun 13, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/5957
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved method of spectrographically measuring density of a strip of photographic negative color film is disclosed. The method includes the steps of concurrently projecting an image of a photographic negative color film, having certain images recorded thereon, on each of a plurality of smaller divisional light beam receiving faces of an image receiving element with the aid of a plurality of projection optical systems. The optical systems include a color separating filter for separating projected light into three primary colors. The method further includes electrically scanning a number of photoelectric converting elements located on each light beam receiving faces, producing an output signal obtained by electrical scanning each face and storing the signal, and measuring relative density, degree of saturation and average density with respect to a part on the photographic negative color film corresponding to each of the light beam receiving face with reference to the stored signals. The smaller divisional light beam receiving faces are prepared by dividing a light beam receiving face having a large number of photoelectric converting elements arranged thereover in a two-dimensiona…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.