(19)
(11) EP 0 348 205 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
13.06.1990 Bulletin 1990/24

(43) Date of publication A2:
27.12.1989 Bulletin 1989/52

(21) Application number: 89306338.8

(22) Date of filing: 23.06.1989
(51) International Patent Classification (IPC)4H01J 29/00, H01J 29/76
(84) Designated Contracting States:
DE GB SE

(30) Priority: 24.06.1988 JP 156411/88

(71) Applicant: VICTOR COMPANY OF JAPAN, LIMITED
Yokohama-Shi Kanagawa-Ken 221 (JP)

(72) Inventors:
  • Ono, Kimiteru
    Iwai-Shi Ibaraki-Ken (JP)
  • Hakamada, Yoshiro
    Noda-Shi Chiba-Ken (JP)

(74) Representative: Crawford, Andrew Birkby et al
A.A. THORNTON & CO. Northumberland House 303-306 High Holborn
London WC1V 7LE
London WC1V 7LE (GB)


(56) References cited: : 
   
       


    (54) Device for suppression of leakage of magnetic flux in display apparatus


    (57) There is disclosed a device for suppression of leakage flux from a deflecting yoke, which is assembled in a display apparatus having a cathode ray tube (a CRT) for displaying an image by radiation of an electron beam from an electron gun to a fluorescent display surface, and the deflecting yoke having some coils arranged at a rear portion of the CRT and for deflecting the electron beam. The device comprises two cancelling wires (5a, 5b) which are disposed at the inner sides of upper and lower ends in front of the CRT and connected in parallel for generating cancellation flux to negate the leakage flux from the coils, and a control circuit (10) for controlling the cancellation flux generated by the wires in the manner that the leakage flux from a face-plate of the CRT is reduced by regulation of current value supplied to the wires.







    Search report