Exposure controlling apparatus
US4939537A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1989 |
| Grant date | Jul 3, 1990 |
| Priority date | — |
| Expiry date | Oct 3, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B27/73
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A color copying machine for copying an image on a photosensitive material having a movable scanning exposure element with a light source for irradiating a document to be copied and projecting light reflected from the document through a window. At most, two of three primary color filters correct the spectral intensity of the light by being inserted into the light path in both directions perpendicular to the direction in which the photosensitive material is conveyed. The ratio of the total area of a sectional plane of the light path to the area of the sectional plane covered by the color correction filter is adjusted to obtain the required spectral intensity. At least one diaphragm in the light path regulates the sectional plane of the light path whereby the controlled diaphragm does not cause a change in the adjusted ratio, and the amount of light is regulated without changing the corrected spectral intensity thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.