CRT graphic terminals

Graphic terminals are primarily of two types: CRT displays and electromechanical plotters. CRT terminals for graphic applications require the ability to draw lines and move spots on the face of the CRT, as well as printing alphanumeric characters. Since most graphic applications require a two-way interaction between the user and the computer, some form of graphic input, such as a light pen,a RAND tablet, or a cursor, is required. Most graphic applications also require an alphanumeric keyboard for manual input.; 圖形終端基本有兩類:CRT顯示器和機電繪圖儀。在圖形應用中，要求CRT終端具有畫線、移 動光點及顯示字符的能力。由于多數圖形應用要求用戶和計算機 之間雙向交互作用,所以CRT圖形終端應具有某些形式的圖形輸入手段,如光筆、RAND圖形輸 入項、光標等,同時也應有一個人工輸入用的鍵盤。