Abstract :
Dark-trace tubes or skiatrons have certain advantages over bright display tubes which make their use desirable for information displays. These advantages are the ability to integrate visually, to store information, and daylight and sunlight viewing. Since World War II, at the time the 4AP10 was used, several of the basic disadvantages have been corrected in part, such as erase time, writing speed, contrast and color. Several experimental tube types have been evolved and others are under development. Some radical improvements in one or more of the limiting characteristics have been achieved. These were accomplished in several ways, including low heat capacity screens, conductive film techniques, different screen compositions, special electron optics, and other techniques. The characteristics and limitations are summarized for different tube types together with several suggestions for possible further research and development in the field. The equipment design factors peculiar to these tubes, such as stringent voltage requirements, sweep failure protection, beam current limiting circuitry, and other items are discussed to aid preliminary equipment designers in the use of these tubes.
