EXPOSURE DEVICE FOR COLOR CATHODE-RAY TUBE

PURPOSE:To form a normal color phosphor screen even if a panel of which shape and size are slightly different from the datum value is used, by measuring a distance and correlative position from a light source to the panel and constituting a color cathode-ray tube in such a state as correcting the position and the attitude of the light source relative to the panel based on the results of measurement. CONSTITUTION:Following methods are adopted for an exposure device in which a photosensitive black lead film or a three-primary-color phosphor film formed on the inside face of a panel is exposed via a shadow mask and a phosphor screen of a color cathode-ray tube is formed by photolithography: before exposure to assembling of a specified panel 3 and a shadow mask 50, a means (for example, laser, laser 55, 56, 53, 54) for measuring distances between center parts p1, p2 of the panel 3 to be exposed plus sealing faces p3, p4 for surrounding funnel, and light source 11 for exposure, and a means for measuring parallel moving components of the light source for exposure and the panel are provided. The position and inclination of the light source 11 for exposure are corrected based on three-dimensional coordinates obtained by these measuring means.