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In Europe, the USA, and Japan, the race is on to produce a new generation of television sets. These new sets will be larger than today's models, possibly with 100-centimetre flat screens. Picture quality will be excellent, crisp, and without flicker, as good as those we are used to seeing in the cinema. Sound quality too will be superb, thanks to digital multitrack transmissions. By the turn of the century such sets may be offering programmes in a choice of languages as they will be equipped with eight sound tracks.

In Europe, the term HDTV is used. In the USA, the more generic term ATV, Advanced Television, has been adopted. The Japanese, who were the first to start work on the new technology, in 1974, called their system Hi-Vision. Whatever name is used, these new sets share certain features.

The picture is displayed using more lines per frame. This means that they provide clearer, more detailed, high quality images. The picture can be displayed on large, wide screens which are flicker-free. They also provide very high quality three-dimensional sound output.

A wider range of frequencies can be used to transmit each HDTV channel. This is because they can be transmitted at high frequencies which are virtually unused at present. These wide frequency ranges make it possible to transmit digital, rather than analogue signals. Digital processing can then be used in the receivers to provide almost perfect pictures even when the strength of the input signal is low. A computer could also be used to produce special effects.

Since not everyone is convinced of the need for such high quality TV systems, the move towards HDTV is likely to be very gradual. The first HDTV receivers will need to be able to process both the old and the new transmissions and, throughout the world, agreement will have to be reached on new transmission standards.