Device for document filming

US3947112A · kind A · utility

Assignee

• VEB Pentacon Dresden · DE

Inventors

• Erich Hahn · Dresden, DE
• Frank Reissig · Dresden, DE

Key dates

• Filing date: Jun 24, 1974
• Grant date: Mar 30, 1976
• Expiry date: Jun 24, 1994

Classification

• Technology area (CPC G): Physics
• CPC primary: G01J1/4223
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A document photographing device has a surface for supporting a document to be photographed, a camera positioned about the surface, to receive light reflected from and transmitted by a document supported on the surface, and separate means for illuminating the document from above and below respectively. An exposure meter receives light reflected from or transmitted through the document and indicates when correct exposure conditions have been set. The exposure meter includes correction means for correcting the reading of the exposure meter to take account of the different spectral radiation characteristics of the illuminating means.