Colour TV tube with luminescent zones on screen - has shadow mask electrode coated with layer of lead deposited by galvanic process

摘要

In the colour television tube, the screen has different colour luminescent zones with a colour selection electrode near the screen. This electrode is made with holes, which allows passage of electron beams derived from the cathode gun. The beams are focused on to zones of one colour, the local convexity of the colour selection electrode is limited to a minimum during the operation of the tube. The side of the colour electrode (12) remote from the screen is coated with a layer of lead deposited by a galvanic process. The thickness of the lead layer is within a given range. The lead layer is blackened and has a heat emission coefficient just below unity.