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(46) Picturephone service, which will become available commercially in the 1970s, will at first probably be used by large business corporations. (47) It is already clear that "the next best thing to being there" is going to be a Picturephone call.
(48) This "new light", first produced by scientists in 1960, can beam continuously and with extraordinary intensity. (49) In other words, they are thinking of using light for the same purpose radio waves are used—to transmit telephone calls, TV programs, and data messages from one point to another. With the expansion of Picturephone service and highspeed data communications between computers, present message-carrying capacities may soon become inadequate. As it turns out to be technically and economically’ sound, the laser might prove to be a major breakthrough in telephone communications.
Current research in telephone communications is so extensive and changes are coming about so rapidly that no one can predict with accuracy what the telephone of tomorrow will look like. (50) 。
A. But as Picturephone service becomes available, it will no doubt spread from the office to the home.
B. Instead of using light to see by, telephone researchers are thinking of ways to use light to communicate by.
C. For many people the most’ exciting development in recent years is Picturephone service.
D. One area that is being seriously considered is communications service "on the move".
E. But there is at least one prediction that can be made with assurance: There will be more and more telephones in the future, and they will be better ones.
F. Possibly the most significant research now being conducted is in the use of the laser beam in telephone communications.