近來由於個人電腦風行，硬體的更新一日千里，CPU由486更新爲P-Ⅲ等級，碟由120MB擴展到13GB以上，軟體的等級也跟著三級跳，如AutoCAD由R10版到2000版，由於軟硬體的升等，使得原本需要大量成本的數化作業也變得平民化，平價化，而螢幕數化也因此成爲可大量執行的成圖數化方式之一。本文主要是探討螢幕數化模式在運用原稿、使用工具上的改變，並比較使用的材料、設備及工時。

Personal computer will be in fashion recently. The development of hardware makes progress at a tremendous pace. The promotion of CPU is from 486 to P-Ⅲ, and the hard disc's volume from 120MB to over 13GB. The software also has great growth. For example, the version of AutoCAD is from R10 to 2000. The update of software and hardware make the cost of digital mapping becoming familiar and cheaper so screen digitizing become one of the digital mapping methods. The paper is based on difference of using original draft and digital tools between screen digitizing model and others. And compare screen digitizing model with others about using material, equipment and working-hour.