随着国内外传真通信的迅速发展,传真机以较短的周期在更新换代。80年代末期出现了最新型的四类传真机即G_4机后。使整个传真通信系统发生了根本的巨大变化,迎来了国际传真通信更大发展的全盛时期。本文论述了有关G_4机新技术及它的分类标准、性能特点、组成原理、连网应用及其发展趋势。 With the rapid development of fax communication at home and abroad, fax machines are being replaced with shorter cycles. The late 80s appeared the latest four types of fax machines that G_4 machines. The entire facsimile communication system has undergone tremendous fundamental changes, ushering in the heyday of the greater development of international facsimile communications. This article discusses the new technology G_4 machine and its classification standards, performance characteristics, composition principle, networking applications and its development trend.