Lateral magnetic shielding for color crt
AssigneeThomson Licensing
InventorsGoffredo Antonelli, Cesare De Paolis, Giuseppe Giannantonio, Paolo Ginesti
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Abstract
Color cathode-ray tube comprising a color selection mask (16) held under tension between a first pair of opposed long sides (30) of an approximately rectangular metal frame (21), a main magnetic screen (22) placed at the rear of the frame in the funnel-shaped part (11) of the tube's envelope, and additional means (50) for forming a screen against the Earth's magnetic field in the part lying along the second pair of opposed short sides of the frame.
Claims5
Cathode-ray tube (10) in the form of a glass envelope characterized by a front face (12) inside which is a luminescent screen (15), the said front face being sealed to a funnel-shaped part (11), a color selection electrode (16) placed so as to face the luminescent screen and held under tension by an approximately rectangular frame (21) having a pair of long sides (30) and a pair of short sides (40), the color selection electrode being fixed under tension to a first pair of opposed sides, the edges of the sides of the frame which constitute the second pair extending towards the screen and lying beneath the surface of the color selection electrode, the edges of the second pair and the surface of the color selection electrode have a open space 45 therebetween, and a main magnetic screen (22) fixed to the frame and extending to the rear of the funnel-shaped part of the tube's envelope,wherein the tube includes complementary means (50, 51) for making a screen against the Earth's magnetic field, these means being placed so as to cover, at least partially, the open space between the edges of the second pair of sides and the surface of the mask.
Dependencies are inferred from the claim text.