TELEVISION ATTACKED

Evening Star, Issue 19892, 14 June 1928, Page 3

TELEVISION ATTACKED

UP AGAINST A STONE WAIL With television so much before the eyes of the radio world, the following article from tho ‘ Cape Times ’ is of much inkiest:— ’The British piouee: of television has been challenged. ‘Popular Wireless,’ tin; well-known radio weekly, has made him an offer of £I,OOO if he will televise certain specified items over a distance of twenty-five yards, to the satisfaction ot a special committee. This attack upon Britain’s foremost television inventor by wireless experts will probably cause the world in general to ask many questions. What‘is it all about? Why this apparent estrangement between two radio “brothers” who for years past have been biasing similar trails in the ether and grappling with problems in common? Television is surely but a development of wireless-—then why should the interested parties fall out? Tho editor of*‘Popular Wireless’ says that such criticisms as ho has made have been supported by two eminent scientists. One of these gentlemen, it may be supposed, is Sir Oliver Lodge, who happens to ho scientific adviser to the popular wireless journal. As far as one can gather at this distance, tho opinion is widely held among radio experts in England that Mr Baird has reached a stage in the development of television where he cannot possibly hope to advance further without some radical change in his system. Optical difficulties, it is claimed, stand in tho way, and more especially mechanical difficulties. In tho world to-day three prominent inventors are attempting to perfect television. They are Mr J. L. Baird (England), Mr C. Francis Jenkins (America), and the Bell Telephone Laboratories of the United States. The three are working along different lines, but actually they are all handicapped in progress by the same mechanical limitations and disabilities.

1 Popular Wireless’ and the “two eminent scientists ” behind it probably hold the view of many others—that Baird’s system cannot possibly be developed to a satisfactory commercial proposition along present lines, and it is possible that the intention of the challenge is to focus public attention on the activities of the newly-formed television company, with the object of exposing the limitations of television before any attempt is made to introduce to the public television apparatus which may be of little practical use and far from perfect. I do not say this is definitely the motive, but in the circumstances I assume that it might bo so. In .other words, the wireless press people seem to think that Mr Baird has attached too much importance to his invention, the limitations of which were well known from the beginning, I have already mentioned that these difficulties are chiefly mechanical, as well as optical. The greatest problem presents itself when one attorn—‘-to televise action—a moving picture—for one immediately leaves the realm, of “ still ” photography and enters cinematography. > 1 , In motion picture work it is a wellknown fact that pictures on the film must pass the gate of the projector at the rate of sixteen a second in order to give true lifelike motion on the screen. The same thing applies to television. and that is where the greatest difficulty comes in—viz., speed.' If one examines with a magnifying glass an ordinary half-tone block reprounction in a newspaper, it will bo seen that every square inch of picture is made up of something like 6,400 dots, which is by no means the finest screen used in Press picture work. Now, to transmit such a picture—and every dot has to be sent—across distance by wire nr wireless is a comparatively simple process, as long as there is no limit in the time to be taken. Hundreds

of experiments have already been successfully carried out on these hues. Pictures, cheques, and handwriting have been exchanged between no continent and another, and Marconi is already talking of introducing his facsijnile transmission at an early date. But this is merely “ still ” photography. The pioneers of ■ television, however, are up against a much tougher problem, for they have to transmit and receive sixteen pictures a second. The whole analysis of the sequence of pictures has first to bo broken up into countless thousands of tiny dots, impulses or atoms, to give a picture of reasonable size, and the building up at tho receiving end must take place at precisely tho same rate to give the idea of motion. NECESSARY SPEED IMPOSSIBLE ■ TO ATTAIN. Those who criticise Baird’s system, which makes use of perforated revolving discs for the transmision and reception of picture elements, declare that nothing mechanical can possibly stand up to the speed required to televise pictures of lifelike motion. They admit, however, that if tho mechanical parts could be dispensed with, and the whole production left to the_ realm of electro-psychics, with no moving parts, television passing the standing of cinematography—a standard less *..an which the general public will probably not regard as perfect—would be quite possible. But as yet nobody has discovered’ such a desirable system. Other difficulties also present themselves in television. Straight lines do not always Appear as such at the reiving end, and while this can he corrected by using a travelling cylinder at the receiving end when transmitting “ still ” pictures, it is not possible with true television. There is reason to believe that this known difficulty of retaining the true definition and shane of objects transmitted has promoted the challenger to stipulate the special items nominated, which include human faces, a tray of dice and marbles, simple geometrical figures, and a clock face.