METHOD FOR APPLYING CODE MARK TO FACE PANEL OF CATHODE-RAY TUBE Russian patent published in 1999 - IPC

FIELD: electronic engineering. SUBSTANCE: method for applying code mark onto face panel of cathode-ray tube having external and internal surfaces with scanning area surrounded by a number of various luminescent phosphors separated by light-absorbing material involves following procedures: appropriate photoresist is deposited onto inner surface of panel to form layer stretching over scanning area to peripheral region; photoresist sections are illuminated both on scanning area and on peripheral region by actinic rays to afford selective variation of photoresist solubility; photoresist is developed to remove its more soluble sections thereby exposing sections of panel inner surface located under them while saving sections of less soluble photoresist. Saved sections of photoresist and exposed sections of inner surface of panel are then covered with light-absorbing material which is dried out to form coating. Light-absorbing coating is developed by removing saved sections of photoresist together with its light-absorbing coating while saving light-absorbing coating adhered to exposed sections of inner surface of panel. Formed in the course of developing are holes in light-absorbing coating on scanning area and code mark that includes pattern of light-absorbing material and open sections on peripheral region of panel. EFFECT: facilitated procedure. 7 cl, 9 dwg