The Design And Made Of Electron Gun In Wide Pannel CRT

Today, following the CRT development,and the digital television popularizing, people have some high requirement to TV. Now, there are some new kinds flat displays have appeared in the market. ( such as LCD,PDP). In order to accommodate in the market circumstance, our company empolder a new type CRT——16:9 wide / 32 inch (W76MAG185X***). This CRT adopt some advanced technic in its parts, such as panel, funnel,assembly mask, electron gun system and deflecxion yoke etc. This made the assembly tube's performance excellent, and have strength in competing.As the corn of CRT, the electron gun has also been hoped improving on performance.Now,the Multi Pre Focus system is applied on the electron gun which is used on 29"PF CRT in our company. It is Hi-BPF gun. In 32"PF electron gun, the Quadruple lens is used. It can bring non-axes-symmetrical field; in main lens, the effective apertures are larger. Toward the requirement of HDTV,the electron gun applied the dynamic focus technic. The focus voltage is divided in two parts: Vg3-1 (focus voltage) and Vg3-2 (dynamic voltage) based on Hi-BPF electron gun. The dynamic voltage is changed according to the parabola with the change of deflexion magnetic field. The two parts bring the quadruple, and the spot shape is improved. The spot sizes in the screen's center and corner could come to the best at the same time. It come over the astigmatic and dispersing focus which was brought from the screen figure and deflecxion。Moreover, the structure of this electron gun is simple compared to other company's same product, and it make the cost down at a certain extend. At the beginning , It have some matter, such as ?V foc, low cutoff value and high beam gyre。Through investigation and experiments, the matter was solved when we change the electron's parts and the electrode assembly.Now, this electrode gun has been used on 32"PF tube entirely,...