Ultra-large deflection flat coil without ferrite core

Abstract

An ultra-large-deflection flat coil without ferrite core for CRT has a pair of rectangular frame deflection coils and a pair of rectangular line deflection coils, which are perpendicularly arranged on a plane. A magnetic shielding ring perpendicular to said plane is arranged in the center. A predeflection coil can be wound on said ring as sleeve of the neck of CRT. Its advantages are large deflection angle and high deflection sensitivity.

Description

Technical field: [0001] The invention relates to a super large deflection planar coil of a picture tube, in particular to a super large deflection planar coil of a picture tube without a ferrite magnetic core, belonging to the technical field of electrical basic electrical components. Background technique: [0002] With the development of high-definition television and multimedia, picture tubes are also developing towards high-definition, large screen and flattening, and the key to flattening is to further increase the deflection angle. The neck of a traditional picture tube is cylindrical, followed by a trumpet-shaped opening, so the inner wall of the deflection coil that scans the electron beam is also made into a corresponding shape to match the outer wall of the picture tube. At present, the large-screen deflection yokes all have trumpet-shaped ferrite cores, and are tightly assembled with the line deflection and frame deflection yokes. However, when the deflection angl...

AI Technical Summary

Problems solved by technology

As the scanning frequency increases, the loss of the ferrite core will increase greatly, causing temperature rise and deteriorating the performance of the magnetic core, thereby affecting the scanning performance and causing adverse consequences.

In the 4th issue of "Color Picture Tube" magazine in 1997, Li Menghu's article "Research and Application of Magnetic Materials in DY Design" pointed out that "the scanning frequency of ultra-high resolution displays is as high as 64-128KHZ, due to the existence of hysteresis loss and residual magnetic loss , eddy current loss, and reluctance loss, so the deflection yoke often works above the normal temperature, and when the deflection current is under abnormal working conditions, these will cause the magnetization saturation effect, which will change the Fourier harmonic component of the magnetic field and cause the electron beam Convergence drift, grating distortion degradation, deflection sensitivity reduction, etc.

"At the same time, it is also pointed out that the significant feature of the high frequency loss of the ferrite core is that it will cause temperature rise, which will affect other magnetic properties, and finally affect the performance of the deflection coil.

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