Method of copying transparent originals and photographic copier

US5978066A · kind A · utility

Assignee

• Agfa-Gevaert NV · BE

Inventors

• Helmut Treiber · Munich, DE
• Friedrich Jacob · Munich, DE
• Gunter Findeis · Sauerlach, DE

Key dates

• Filing date: Oct 6, 1997
• Grant date: Nov 2, 1999
• Expiry date: Oct 6, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G03B27/52
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Film frames are scanned preparatory to copying and a set of density values is generated for each frame. When a frame exhibits excessive contrast, a mask is calculated using the respective set of density values. The calculated mask is formed on an LCD or LED matrix which is in register with the frame. An image of the masked frame is then projected onto copy paper by a zoom objective. The mask has a size which is a function of the magnification factor and/or the mask-to-frame distance.