EP 0205218 B1 19891018 - MULTIBEAM CATHODE RAY TUBE AND DEVICE COMPRISING SUCH A TUBE
Title (en)
MULTIBEAM CATHODE RAY TUBE AND DEVICE COMPRISING SUCH A TUBE
Publication
Application
Priority
NL 8501666 A 19850610
Abstract (en)
[origin: EP0205218A1] A multibeam cathode ray tube having in an evacuated envelope (1) an electrode-optical system (6) centred around an axis (9) and comprising means to generate at least two electron beams which are each focussed to form a spot on a display screen (28) in the tube by means of common focussing means (27) centred around the axis (9) and which are deflected over said display screen (28) by deflection means (29), a common convergence lens (25, 26) being present between the means for generating the beams and the focussing means and being centred around the axis (9). If said convergence lens (25, 26) has such a strength that the distance between the axis of the outermost electron beam (21) to the axis (9) of the electron-optical system (6) is at least five times smaller than the maximum diameter (d) of the individual beams in the focussing and deflection means, one common focussing lens may be used as a result of which all beams are focussed to substantially the same extent and substantially no disortion occurs of the spot frame upon deflecting the beams.
IPC 1-7
IPC 8 full level
H01J 29/46 (2006.01); H01J 29/58 (2006.01)
CPC (source: EP KR)
H01J 29/46 (2013.01 - EP); H01J 29/51 (2013.01 - KR)
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0205218 A1 19861217; EP 0205218 B1 19891018; DE 3666523 D1 19891123; JP S61285644 A 19861216; KR 870000742 A 19870220; NL 8501666 A 19870102
DOCDB simple family (application)
EP 86200992 A 19860609; DE 3666523 T 19860609; JP 13199086 A 19860609; KR 860004523 A 19860607; NL 8501666 A 19850610