Methods of and apparatus for applying stripe-patterned fluorescent films to screen portions of colour cathode ray tubes

摘要

In order to form a fluorescent surface on a panel (9) of a colour cathode ray tube, a light source is placed at a number of positions (02, 0, Q1) and exposed at each position to a photoresist film (10) on the inside surface of the panel to form prescribed stripe width patterns using a transmission light intensity distribution formed by superposed plural Fresnel diffraction waveforms. Exposure is effected in the different positions via different correction lens systems (12, 28,, 282) selected to correspond to the exposure at the various light source positions and the absolute value of the transmission light intensity distribution and the derivative (dl/dx) of the transmission light intensity distribution at positions corresponding to the edge of the stripe width pattern are optimised over the entire inside surface of the panel.