Optimum Selection of Thermal Compensation Spring for 15" Iron Mask CMT by Finite Element Method

抄録

Thermal behavior of shadow mask is a critical problem of flat square tube design, especially for the size of tube is bigger than fourteen inches. To prevent the misregister of electron beam with respect to phosphor dots, the common solution for most of CMT factories is using low thermal expansion coefficient mask material Invar instead of Iron material. However, the price of Invar is more expensive than that of Iron mask. For the cost reduction purpose, Philips developed a new 15" CMT with Iron mask and the suspension system was changed with bi-metal thermal compensation spring. This paper presents the finite element simulation model to select bi-metal spring for 15" Iron mask CMT, and makes a comparison between simulation results and the thermal performance of tube compensated by this bi-metal spring.