Projection tube

Abstract

A projection tube, the negative curved surface of the projection tube glass shell is coated with fluorescent powder, the neck of the projection tube is coated with graphite, the inside of the tube is coated with aluminum film, and the tail of the projection tube is equipped with an electron gun. The electron gun is composed of a modulation electrode (G1), an acceleration electrode (G2), The first anode electrode (G3), the focus electrode (G4), the second anode electrode (G5), the acceleration electrode (G2), and the first anode electrode (G3) form a pre-focus, the first anode electrode (G3), the focus electrode ( G4) constitutes the auxiliary lens, the focusing electrode (G4) and the second anode electrode (G5) constitute the main lens, the anode voltage of 32KV is applied to the first anode electrode (G3) and the second anode electrode (G5), and the focusing voltage of 7-9KV Add to focusing electrode (G4). The invention has high focusing voltage, single-potential electrostatic focusing electron gun, enhanced pre-focusing effect, improved definition of projection tubes, and is suitable for producing projection tubes with various specifications such as 16, 19, and 22 centimeters.

Description

technical field [0001] The invention relates to a projection tube, in particular to a projection tube used in a rear projection TV. Background technique [0002] Most of the existing black-and-white or color projection tubes have low brightness, poor definition, poor voltage resistance, and unreasonable design of the electron gun, especially when the outer diameters of the first anode electrode G3 and the focusing electrode G4 are equal. As the current increases, the size of the light spot also increases, which affects the projection effect, and the prior art cannot meet the requirement of the definition of the projection tube. At the same time, the electrode flanging treatment is not reasonable enough, and it cannot meet the pressure resistance requirements of the projection tube. Contents of the invention [0003] The object of the present invention is to provide a projection tube with high brightness, high definition and high withstand voltage. [0004] Realize the te...

AI Technical Summary

Problems solved by technology

[0002] Most of the existing black-and-white or color projection tubes have low brightness, poor definition, poor voltage resistance, and unreasonable design of the electron gun, especially when the outer diameters of the first anode electrode G3 and the focusing electrode G4 are equal. As the current increases, the size of the light spot also increases, which affects the projection effect. The existing technology cannot meet the requirements of the definition of the projection tube.

At the same time, the electrode flanging treatment is not reasonable enough, and it cannot meet the pressure resistance requirements of the projection tube.

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