Patent Number: 6,297,600

Title: Blanked dynamic focus power supply transient elimination

Abstract: In order to accurately measure a low current bias in an automatic kine bias (AKB) circuit during several video lines that immediately follow vertical retrace, dynamic focus is interrupted by deactivating a dynamic focus voltage amplifier. The amplifier draws its power from a horizontal flyback transformer. In order to avoid a horizontal transient which may occur when the dynamic focus voltage amplifier is reactivated after being deactivated during a vertical blanking interval, the dynamic focus amplifier draws a current during vertical blanking which approximates the average current drawn during vertical scan.

Inventors: George; John Barrett (Carmel, IN)

Assignee: Thomson Licensing, S.A.

International Classification: H04N 3/26 (20060101); G09G 001/04 ()

Expiration Date: 10/02/2018