Patent · US Expired

Correction of fixed pattern noise

US6086252A · kind A · utility

4Cited by

8References

12Claims

0Family size

Assignee

U.S. Philips Corporation · US

Inventors

Peter Quadflieg · Aachen, DE
Gerhard Spekowius · Straelen, DE

Key dates

Filing date	Sep 27, 1999
Grant date	Jul 11, 2000
Priority date	—
Expiry date	Sep 27, 2019

Classification

Technology area (CPC H)Electricity
CPC primaryH01J2231/50036
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

An X-ray image intensifier (1) includes an entrance screen (2) with a photocathode (3). A television camera (15) is optically coupled to the exit window (12) of the X-ray image intensifier. The X-ray image intensifier with the television camera derives a primary image signal form an X-ray image on the entrance screen. The X-ray image intensifier is provided with a radiation source (4), such as flashlights or LEDs, for irradiating the photocathode (3). Irradiation of the photocathode produces a light intensity distribution on the exit window wherefrom the television camera derives a control signal. Correction numbers are derived from the signal levels of the control signal. These correction numbers are employed for correcting the primary image signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.