Patent ID: 6013400
Filing Date: 2000-01-11
Classification: H01J

Abstract:
A method of manufacturing a luminescent screen assembly with a light-absorbing matrix, having a plurality of substantially equally sized openings therein, on an inner surface of a CRT faceplate panel with a color selection electrode spaced from said inner surface of said faceplate panel by a distance, Q, said color selection electrode having a plurality of first strands interleaved with slots, said slots being wider than said first strands, said method comprising the steps of:a) providing a first negative acting photoresist layer, whose solubility is altered when it is exposed to light, on the inner surface of the faceplate panel;b) exposing, through said slots in said color selection electrode, said first negative acting photoresist layer to light from at least two symmetrically located source positions, +G and -G, relative to a central source position, 0, to selectively alter the solubility of the illuminated areas of said first negative acting photoresist layer, thereby producing shaded regions with greater solubility and illuminated regions with lesser solubility;c) removing the shaded regions of said first negative acting photoresist layer with greater solubility, thereby uncovering areas of said inner surface of said faceplate panel, while retaining said illuminated regions of lesser solubility;d) overcoating said areas and said retained illuminated regions with a composition of light-absorbing material;e) removing said retained illuminated regions and the light-absorbing material thereon, thereby uncovering portions of said inner surface of said faceplate panel while retaining first guardbands of said light-absorbing material adhered to said inner surface of said faceplate panel;f) repeating steps a) through e) twice more, using second and third negative acting photoresist layers and additional asymmetrically located light source positions +B,-B and +R,-R, respectively, to uncover portions of said inner surface of said faceplate panel and produce second and third guardbands of said light-absorbing material, each of the six light source positions being different from each other; andg) depositing phosphor materials onto the uncovered portions of the inner surface of the faceplate panel.