In the era of digital technology, display device is the one of the important interface tool to communicate and transmit the information. Among the various display devices, CRT is the most popular one. Even though the CRT has many advantages comparing to other devices, it is faced to overcome its a few disadvantages especially in volume, shape and price, etc, In this paper, we try to show the development strategy of CRT corresponding with flat displays in the view point of ergonomics.