Television is not a visual medium. Appearances are deceiving. TV might have turned into a medium of real visual communication; it was pretty darn visual in its early years, when still at the miracle state. But somewhere it went awry and became illustrated radio, and poorly illustrated radio at that.

In prime-time entertainment, television rarely offers an eyeful, much less two eyes full. A wan visual sameness pervades programming, almost all of which is shot within a few square miles in and around Hollywood, which is no man's land for reality. Seldom is there the opportunity to be visually delighted or engaged by the picture we see on TV, except of course during "Charlie's Angles" or commercials.

Commercials often communicate on a more purely visual level than programs. They're better photographed, edited for maximum impact, and often shot on location, so that they show us much more of the world around us than programs do. RCA wants us to see the Grand Canyon in its true colors, says a gorgeous ad for TV sets, and see it we do -- for about 10 seconds.

ABC's current coverage of the Winter Olympics has offered innumerable striking sights, perhaps none more spectacular than the opening ceremonies, which had viewers raving in appreciation. But the sporting events themselves are often saddled with so much extraneous, incessant commentary that the audio overwhelms the video and it begins to look as if the schussing and swooping down snowy slopes are accompaniment to the bablings of announcers and not the other way around.

As for TV news, it has become persistently less visual during recent years, even though there have been leaps and strides in the technology of getting picutres on the air. Partly it's a matter of corespondents and anchormen simply refusing to shut up and let pictures talk.

How can the picture be a star when the reporter wants to be a star -- and to stand in front of a building delivering pronouncements?

Reuven Frank, the former president of NBC News who originally teamed Chet Huntley and David Brinkley and produced such acclaimed documentaries as "The Tunnel," says TV news has completely subordinated pictures to talk. What we have in effect is Television for the Blind.

"Television could be a visual medium," Frank says. "But there's no such thing as photojournalism on television now. You'd think it would be the ideal medium for photojournalism, where the picture tells the story. What we have now in TV news is the need for a picture only because the television tube exists; you have a guy standing outside a building telling you what is going on inside a building into which he is not allowing to go. He only knows what's going on in there because someone at the New York desk called him up and told him."

Frank says TV has changed the way it covers news and in the process made pictures not the indipensable essence but virtually frilly; they don't don't so much tell the story as fill space.

"It used to be in covering news for TV that the writing of the script was the last act," says Frank. "First you went out and showed what was happening. Then you arranged the pictures in the order dictated by the story. Then someone who knew the story wrote the script to go with it.

"Now the standard way of doing it is that the words are written and spoken and then the pictures, such as they are, are hung on the words. Such pictures as do not fit the script are left on the floor. A camera crew won't even film some things unless they know they are going to be talked about in advance. It used to be that e would write contrapuntally to the pictures, but now that's all gone, and most of the time there is no reason to have pictures except that it's TV and you have to put something on the screen."

What's put on the screen in often a lot of spurious and frivolous illustration to reinforce or enhance the dialogue. In a January broadcast of the NBC Nightly News, during a story on Scholastic Aptitude Test scores, a reporter compared them to "an accurate roll of the dice." At this point a picture of a pair of dice popped up on the screen.

Frank calls this approach "comic book" and says it ironically gets worse with advances in electronic manipulation of pictures to be put on the screen. There is increased use of drawings, graphs, and gimmicks of all kinds, relevance not usually a criterion. Frank says, "The next thing will be 'pow!' and 'bam!' and 'sock!'" like in comic strips.

Frank was executive producer of a brave and industrious NBC magazine show called "Weekend," and he recalls a telltale comment made to him by a student doing a master's thesis in communication. "Well, the trouble with 'Weekend,'" the student said, "is that it's too visually oriented." It was television for people who can see.