Colour display tube with coma correction

(19)

(11)

EP 0 517 320 A3

(12)	EUROPEAN PATENT APPLICATION

(88)	Date of publication A3:
	18.11.1993 Bulletin 1993/46

(43)	Date of publication A2:
	09.12.1992 Bulletin 1992/50

(21)	Application number: 92201573.0

(22)	Date of filing: 02.06.1992

(51)	International Patent Classification (IPC)⁵: H01J 29/56

(84)	Designated Contracting States:
	DE FR GB IT

(30)

Priority:

05.06.1991 EP 91201380

(71)	Applicant: Philips Electronics N.V.
	5621 BA Eindhoven (NL)

(72)	Inventor:
	Sluyterman, Albertus Aemilius Seyno NL-5656 AA Eindhoven (NL)

(74)	Representative: Koppen, Jan et al
	INTERNATIONAAL OCTROOIBUREAU B.V., Prof. Holstlaan 6 NL-5656 AA Eindhoven NL-5656 AA Eindhoven (NL)

(56)

References cited: :

(54)	Colour display tube with coma correction

(57) Colour display tube comprising an electron gun system (5) of the "in-line" type and an electromagnetic deflection unit. This unit is provided with coma correctors 14 and 14' at its gun side, which correctors, viewed from the gun system, provide a pincushion-shaped vertical deflection field component and a barrel-shaped vertical deflection field component. These components are used to reduce the "green droop" (= anisotropic Y coma) in the corners and at the ends of the display screen axes to an equal extent without the spot shape of the outer beams being influenced detrimentally. The correction is realized by two magnetic six-pole fields.

Search report