考研

Television --  the most pervasive and persuasive  of modern  technologies, marked by rapid change and  growth -- is moving into  a new  era,  an era  of extraordinary sophistication  and versatility, which promises to reshape our lives and our world. It is an electronic revolution of sorts, made possible by the marriage of television and computer technologies.

The word "television", derived from its Greek (tele: distant) and Latin (visio: sight) roots, can literally be interpreted as sight from a distance. Very simply put, it works in this way: through a sophisticated  system  of    electronics, television provides the  capability of  converting an image(focused on  a special photoconductive plate within  a camera) into electronic impulses, which can be sent through a wire or cable. These impulses, when fed into a receiver (television set), can then be electronically reconstituted into that same image.

Television is more than just an electronic system, however. It is a means of expression, as well as a vehicle for communication, and as such becomes a powerful tool for reaching other human beings.

The  field  of  television  can  be  divided  into  two  categories  determined  by  its  means  of transmission. First, there is broadcast television, which reaches the masses through broad-based airwave  transmission  of  television  signals.    Second,  there  is  nonbroadcast  television,  which provides for the needs of individuals or specific interest groups through controlled transmission techniques.

Traditionally,  television  has  been  a  medium  of  the  masses.  We  are  most  familiar  with broadcast television because it has been with us for about thirty-seven years in a form similar to what exists today. During those years, it has been controlled, for the most part, by the broadcast networks, ABC, NBC, and CBS, who have been the major purveyors of news, information, and entertainment. These giants of broadcasting  have actually shaped  not  only  television  but our perception of it as well. We have come to look upon the picture tube as a source of entertainment, placing our role in this dynamic medium as the passive viewer.首页 1 2 尾页

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