近年来,由于制作了I-L(电流-光输出)待性的线性及调制特性都良好的半导体激光器,人们正在研讨利用半导体激光器的光传输系统进行各种模拟传输。本文旨在论述采用半导体激光器作光源、对光强度直接调制而实施电视信号模拟传输的系统,以此来传输图像。首先,通过测试作为该系统基本特性的基带响应特性和线性,明确了能否用光纤实现电视信号的模拟传输问题。然后,讨论了在实际传输电视信号时,与其特性有关的光纤长度问题。其结果是,在从甚高频到超高频的电视信号模拟传输时,若光纤长度为50米,则所有通道都能获得满意的图象。但是,若光纤长度为1公里,则只能在甚高频下获得满意的图象;在超高频下产生的模式噪音使得图像质量大幅度降低。 In recent years, various types of analog transmission using an optical transmission system using a semiconductor laser have been studied due to the fabrication of a semiconductor laser having good linearity and modulation characteristics of I-L (current-optical output). This paper aims to discuss the use of semiconductor lasers as a light source, the direct modulation of light intensity and the implementation of analog television signal transmission system, in order to transmit images. First of all, by testing the basic characteristics of the system as the baseband response characteristics and linear, clear whether the optical transmission of television signals to achieve the issue of simulation. Then, it discusses the fiber length issues related to its characteristics when actually transmitting television signals. As a result, in the analog transmission of TV signals from VHF to UHF, satisfactory images are obtained for all channels with a fiber length of 50 m. However, if the length of the optical fiber is 1 km, the satisfactory image can only be obtained at very high frequencies; the pattern noise caused by the ultra-high frequency causes the image quality to be greatly reduced.