Picture display device and deflection coil both having self-aligning surfaces

摘要

In a picture display tubes having deflection angles of 110 DEG and more the conical central part near the transition to the neck has a substantially flat variation perpendicular to the tube axis. As a result of this an accurate positioning of the deflection device on the display tube is seriously hampered. This problem is solved by centering members which are present on the conical central part and which cooperate in a self-centering manner with centering members forming part of the supporting cage of the deflection device. The position of the deflection device in the axial direction is accurately fixed by abutment members forming part of the supporting cage in co-operation with abutment surfaces forming part of the envelope of the tube.