A large scale display device such as an advertising having display surface formed by arranging a number of image display tubes lengthwise and breadthwise. The device includes a frame having main posts and block-shaped face plates to each of which a number of image display tubes and a control unit are...http://www.google.se/patents/US4384279?utm_source=gb-gplus-sharePatent US4384279 - Modular large scale image display device
