Better Picture, Better Sound

NEW YORK — High-definition television uses a wider screen and far more picture detail than conventional TV to try to duplicate the experience of watching a theatrical film.

The screen, which is one-third wider than a conventional set’s, better conveys the action in sports events and the drama in movies. That shape, or aspect ratio, also more closely duplicates the human visual field, TV engineers say.

The difference between conventional and high-definition pictures has been described as similar to the difference between a picture in a newspaper and one appearing in a slick-paper news magazine.

The Japanese Muse system, currently the most fully developed technology, produces a picture of 1,125 scanning lines and 60 frames per second; conventional pictures break down to 525 lines and 60 frames per second. A Muse screen consists of 1.5 million pixels, or dot-like picture elements, compared to about 213,000 pixels for conventional television pictures.

The technology is also almost free of the imperfections called artifacts--such as the halos that can appear on plaid jackets--that occasionally plague conventional screens.

High-definition TV sets will be equipped with multichannel sound. Many manufacturers are expected to rely on digital sound reproduction, which will give the sets a sound quality like that of compact disks, according to researchers.

Because of the detail offered by high-definition television, researchers consider it a solution for the fuzzy pictures produced by large-screen TV. They expect that its arrival will also make large-screen viewing far more popular.

Some manufacturers are expected to make television equipment that will project images onto living room walls.