Automatic x-ray exposure unit for mammography

US5371777A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Karlheinz Koehler · Herzogenaurach, DE
• Horst Aichinger · Ergolding, DE

Key dates

• Filing date: May 13, 1993
• Grant date: Dec 6, 1994
• Expiry date: May 13, 2013

Classification

• Technology area (CPC H): Electricity
• CPC primary: H05G1/46
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

An automatic x-ray exposure unit for mammography permits a correction of the mAs product dependent on the subject thickness without the need for obtaining a transparency signal, and thus without the need for the double detector normally needed for that purpose. The automatic x-ray exposure unit permits the correction to be undertaken on site, prior to conducting an actual examination, and thus can be used for film/foil systems, such as customized systems for which no previous transparency data has been obtained. This is accomplished in an automatic x-ray exposure unit where the mAs product is obtained for a fraction (1/n) of the total exposure, and a total exposure value is then obtained by multiplying the fractional value by n. These values are used to generate a characteristic curve, which is stored, for the film/foil system being used. If it is then necessary to switch (adjust) the mAs value due to the subject thickness, this can be done using the stored curve.