8. Прочитайте и письменно переведите текст. Напишите аннотацию и тезисы к тексту.

Television

By J. L. B AIRD,

Managing Director of Baird Television, Ltd.

No one will gainsay that the year 1932 has proved to be a most important landmark in the development of this newest of sciences-television.

After nearly three years of experimental transmissions emanating from the Baird Studios in Long Acre and broadcast by the London Regional transmitter of the B. B. C., a sufficient degree of advancement has been made to justify the B. B. C. taking over the studio side of the work. In my opinion this constitutes the most important step which has yet been taken towards the realising of proper commercialisation and the introduction of television to the public at large.

It may come as a surprise to many to learn that as far back as 1926 television transmissions were broadcast by the B. B. C. These, however, were of an entirely experimental nature and were received only on our own machines; for apparatus at that date was not in the hands of the public. From these crude beginnings we were able to establish that television could be broadcast successfully by the B. B. C. transmitters, and from that date a steady progress commenced.

Negotiations with the B. B. C., which took place over a rather lengthy period, culminated in September 1929, when the first official broadcast of television was made through the new London Regional Station at Brookmans Park. A spirit of friendly collaboration was established and considerable technical knowledge of this important side of television has been acquired.

Steady progress then commenced, one of the results of which was the broadcasting of the play “The Man with the Flower in his Mouth” which was due to the united efforts of Mr. Sydney A. Moseley, Mr. Val Gielgud, and Mr. Lance Sieveking.

Another landmark in television progress was reached in June 1931, when a view of the winning post at the derby was broadcast. This was repeated in 1932.

The most valuable result of the years of experimental broadcasting which have been gone through has been the acquiring of a vast amount of technical experience. I feel, now that the B. B. C. has taken over the programmes and transmissions, advancement will be most rapid and the public can look forward to television programmes of sustained entertainment value.

In spite of the large amount of information which has been disseminated on the subject of television, I find that the majority of the general public are still in complete ignorance of what television means and how the process is effected.

In the space at my disposal, therefore, I propose briefly to outline both the transmitting and receiving sides of the problem.

First of all we mean by television the process of being able to see, through the medium of electrical methods of transmission, the reproduction of images of living, moving, or stationary objects which are at some distance from the observer. It can really be looked upon as the reproduction of sight, for it is possible to witness visually what is happening at some distance just as if we were eye-witnesses on the spot.

Corning to the process itself, the subjects to be televised are positioned in front of a Baird spot-light transmitter – and explored by a rapidly moving spot of light. For the purpose of explanation let us assume we are televising the head and shoulders of an artist. In front of him is a powerful source of light which is broken up mechanically into a rapidly moving spot. This is effected by having a beam of light projected on to a revolving drum around whose outer edge are positioned mirrors, each one set at a slightly different angle to its predecessor. The effect is to cause a tiny area of light to move from the bottom to the top of the subject’s features and thus create a strip of light. Immediately this one spot has finished its movement, a second spot takes its place and performs an identical movement, except that this second strip is displaced to the left of the original strip. In this way 30 strips of light are built up side by side, each strip just touching its neighbour on either side, and although at any one instant only a tiny spot is visible, the process is carried out so rapidly, namely, 12 ½ times per second that an onlooker would have the impression that the artist was completely illuminated.

A bank of photo-electric cells is placed in front of the artist, and this “television eye” follows the movement of the spot of light and picks up that amount of light which is reflected from the spot playing on the subject being televised. A corresponding current variation is then produced in the cell circuit, and at the next instant, when the spot has moved to its adjoining position in the light strip, a different amount of light is reflected and the sells respond accordingly. In this simple way the scene is analyzed, and the television signals are made to modulate the carrier-wave sent out by the broadcasting station and are transmitted through space as ordinary wireless signals. These can be detected and received in the normal manner by anyone possessing a wireless receiver. If, however, the individual turned in vision radio signals and passed them on to a loudspeaker, he would be rewarded with a peculiar note which makes no pretence at being musical. On the other hand, if the signals from the output circuit of the wireless receiver are passed to a “Television receiver”, then the result will be an intelligible image which, in effect, is a replica in miniature of the artist in the television broadcasting studio.

The vision-receiving apparatus, in order to bring this about, must consist of a source of illumination, the intensity of whose light can be made to fluctuate in exact conformation to the variations which originally take place in the photo-electric circuit at the transmitting end. In the original disc model machine this source of illumination was a flat plate neon lamp whose large electrode glowed brightly or darkly according to the signal strength which was made to modulate it.

In the new model machine, however, this neon lamp has been replaced by a projection lamp whose beam of light is now modulated by being passed through Nicol prisms and a glass cell filled with nitro-benzene, in which plates, similarly arranged to accumulator plates, are immersed. These plates are connected to the output of the wireless receiver, and as the voltage varies, the light passed by the cell varies in unison. This grid cell is a modification of the cell used many years ago by the physicist Kerr in his experiments with polarized light, but the use of grids in place of simple plates enables a low voltage to be employed and renders the device practical. The beam of light modulated by the grid cell is projected on to a revolving mirror drum, and this in turn is reflected on to a translucent screen positioned in front of the drum. Since the whole process is effected at a speed of 12 ½ times per second, the characteristic lag or persistence of vision of the eye interprets this as a continuous movement, in much the same way as the still pictures projected on to a screen at an ordinary cinema are built up into the continuous and apparently unbroken movement owing to this same property of the eye. (5973 p.s.)

Комментарий:

to gainsay – отрицать, возражать, противоречить; landmark – достопримечательность; веха; to emanate – происходить; sufficient – достаточный; обоснованный; to justify - объяснять, подтверждать, доказывать; crude – незрелый, непродуманный (о планах, мыслях и т.п.); to commence – начинаться; negotiations – переговоры; to culminate – достигать кульминации; collaboration – сотрудничество; to acquire – получать, приобретать; steady – устойчивый; прочный, надежный, постоянный; derby - дерби ( ежегодные скачки в Эпсоме близ Лондона, проводящиеся с 1780 г.); sustained – длительный, непрерывный, продолжительный; to disseminate – распространять; in complete ignorance – в полном неведении; to witness - видеть, быть свидетелем (чего-л.); eye-witnesses on the spot – видеть всё собственными глазами; to corn – обращать внимание; to assume - допускать, предполагать; to revolve – вращать; вертеть, поворачивать; outer – внешний; predecessor – предшественник; onlooker – зритель, наблюдатель; to illuminate – освещать; to pick up – поднимать, подбирать; instant – мгновение, миг; to adjoin – граничить, прилегать, примыкать, соседствовать; to possess – владеть, иметь, обладать, располагать; intelligible –понятный, четкий, ясный; a replica – первоклассный, превосходный; to fluctuate – быть неустойчивым, меняться; колебаться; колыхаться; to glow – светиться, сверкать; nitro-benzene – нитробензол; to immerse – опускать; in unison – в унисон; grid – решетка, сетка модулятор, энергетическая система; to enable – делать возможным; to render – представлять, выражать, выводить; translucent - просвечивающий; полупрозрачный.