PAGE TWO
#4
HOW TELEVISION WORKS.
·ELECTRIC EYE" THE REAL SECRET,
"ELECTRIC
SYEG
HONGKONG TELEGRAPH, MAY 16th, 1931.
NEON
TUGE
U.S. NATIONAL CATHEDRAL.
LIGACE
SYNCHRONIZED MOTORS
GLOW. Pinte
ENLARGING
FENS
PICTORIAL SUPPLEMENT
ELECTRI
BROADCASTING STATION
SCANNING DISC
The young lady in the broad-, casting station at the left is being "televised" to the receiving sta-1 tion at the right, Light, from the "ght source," goes through the tiny holes in the rotating "sean-j ning ding" which bronks up the beat into many separate dashes. This bruken-up light is reflected the from the girl's face and varying degrees of light and shadow in her relected image are picked up by the "electric yes," which contain a chemical fement; that evaveris light into electricl impulsos. These impulses arej then brondenst to a receivingc set!
DETAIL OF SCANNING DISC
SHE AND
FORM OF IMAGE CINERED BY ONC
RECEIVING STATION
IMAGE
SCANNING DISC
which reproduces these electric speed and phase as the first one-ja “acanning disc." showing the impulses into light dashes by which re-creates the girl's Image, spiral arrangement of the tiny means of a near tube. There re The latter in enlarged by means of holes. Right, a picture of a boy na produced Bashes are projected magnifying lens and thus made) It appears when received by a tele- through other "ranning dise" visible to the man at the right. vision receiving set of the -rotating at exactly the same! At the left, below, is a close-up off sent.
pre-
WIDESPREAD experiments all;trical impulses and reconvert eldental discovery made 11 years
over the world suggest the them into an image of the original] earlier by an English engineer many and varied proteins that face scene has intrigued scientists or named Willoughby Smith. television engineers before this 50 years, The theory has been f Smith, stationed at the Valentia, new miracle of science can be well established, but it the suc-Ireland, terminal of the newly made. praelieni. To understand cessful appileation of this theory completed telegraph cáble from these problems one should know that remiding the chief object of the United States, was trying to exactly what television is and how television research,
measure the electrical resistance It works. The serret of television in 1884 a German scientist for selenium, a chemical element, Hes in the conversion of light into numed Nipkow decided that, by when he noticed that its resistance electrient impulses uni bark again | breaking up a scene into tiny spots was reduced when light struck it. into light. The medium of trans of light and shadow, he rouli] He found also that the resistance, mission, wire or radio, raises only convert each of these spots into anjor rather the conductivity, of a secondary problem.
electrical impulse. He could dol seleniam varied as the intensity How to create, these fast elee-this by taking advantage of un ac- of the light varied.
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Here, therefore, was the means by which Nikow thought he emild convert the variations of light spots in a scene into electrical impulses of, correspruding inten sity. He cut out a metal disc and around its edge, in the form of a spiral, he drilled a series of thy hales, each hole just slightly under the preceding hole and an inch or By umay
Setting the dise up so he could rotate it freely, he placed an ob- jeet on one side and a light-sensi- tive element, like selenium, on the ather, both object and selenium being in direct line through the holes in the disc. He then threw a light on the object and rotated the dine.
Disc Breaks up Light.
As the disc turned, ench hole eut a path of light across the ob- ject and permitted the reflected Rght along that path to pass through it on to Llic selenium. By connecting this element with an electric meter he watched the needle fluctuate back and forth to show the varying amount of cur-. rent going through it in proportion' to the varying amount of light that passed through each hole in the live
As one tiny hole passed neroas the object, the next cut a similar patis directly below, then the next and so on until all the dots had completed cutting paths from top to bottom of the object, permitting Hight from it to pass through to the selenium. This process Nip- kow called "scanning" and this term still is applied to the process of cutting up an image to be televised into paths of light.
pass
Light Is Strengthened, The light permitted to through the disc holes wus CX- tremely faint and produced very little effect on the light-sensitive element behind. In 1910, there- fore, A. Ekstrom. a Swedish in- ventor, derided to put the source of light back of the dise and the light- sensitive element in front and to one side, Where Nipkow originally had his light source. Thus he was [able to "bean" an abject directly
with a strong beam of light.
Selentists soon found other mare sensitive elements thun selenium
put them to une in a vacuum taba form which they called a "photo-electric cel." This is the electric eye", which "aces" the stone to be televised and converts the light variations from It into' corresponding electrical impulsos.
When theseanning diae is ro- Itated before a scene to be televised. by the Ekstrom method, it revis
a beam of light across the scene from side to side and top to bottom. This beam actually in a series of intermittent beams or dots of light passing through the holes of the dise. Each dot of light on the scene lasts only a tiny fraction of R second, as long as the hole through which it passes is between the light source and the scene.
Serles of Flashes,
The action of the scanning dlac results in a series of tiny flashos of light coming from the televised
The National Cathedral at Washington as it will look
when completed.
George Washington's dream of proportions have become notice- n great national church for all"able. is coming truc.
The cathedral is of symbolic Its design expresses atrength. grace and upward growth such as Is found in the works of nature.
It is
Towering high over the capital, Gothic. is a great religious centre Con- structed on Mount St. Alban. In the heart of a 67-acre tract.
The cathedral is in the form of the National Cathedral, sino!
it cross, the arms of which are known as Washington Cathedral, known as the north and Houth but formally dedicated the Cathe-¦ transepts: dral of St. Peter and St. Paul.
One of the most startling exam- The cathedral and associated ples of symbolism is to be seen institutions eventually will present in the carving of seven sins, de- picted ILS Agures in modern the 'most comprehensive religious ellthen, into the cathedral's stone plant of Europe or America. The fabric. Two towers nt the cathedral itself will cost about western end, or entrance, are 196 $10,000,000 but the full expense of feet high, while the central tower Construction and endowment, ofį will be 292 feet high. The tength the church and allied, institutions is 534 feet, the span of the nave will approach $40,000,000.
40 and the height of the nave 95. George Washington, when
10 and the height of the nave 95. pre- sident, dreamed of a national The area is 71,000 square feet. This church for the free workship of The apse rises 147 feet. God, a cathedral in keeping with means it is larger than the cathe
drais of Rheims, Westminster the dignity and beauty of the
Abbey, Canterbury, Amiens, Co- antion's capital.
logne
or Notre Dame. One hundred years later mem- The cathedral is democratic bers of the Protestant Episcopal America's nearest approach to Church, of which Washington was Westminister Abbey. Here al- a member, decided to sponsor a ready are buried Woodrow Wilson. "national cathedral."
Admiral Dewey and other famous
In 1893, Congress granted a men. charter to the Protestant Episco- Scattered about the elose on pal Cathedral Foundation "Tor Mount St. Alban and contiguous the promotion of religion, educa- to the cathedral are several build- tim and charity."
ings already in use. These in-
In 1898. President McKinley clude girls and boys' schools, a spoke nt. the dedication of the library with 300,000 volumes, an Peace Cross which marked the open-air
consecration of the cuthedral site.
feld.
and theatre
athletic
A stone wall with 12 gates. In 1907, the foundation stone of named after the 12 apostlea, will the cathedral was laid and great surround this "Holy City on the progress has since been made, Hin
but the cathedral is far from finished.
The
national committee in Although the general charge of obtaining funds for fur. outline of the church fabric has ther work on the cathedral Is been visible from the air for many headed by General Pershing. years, it is only within recent Visitors already approximate months that the future cruciform 1,000 daily.
scene in an orderly zig-zar form. ESTELLE IN A NEW There are as many Bushes or deta
of light across the scene, and na many lines of light dots from top to botton, as there are holes in the
ROLE.
Poetess.
dise. The total number of light Shows Herself a Budding flushes in a single revolution of the scanning dise, therefore, would be the square of the number of holes In the spiral.
It has been said that every per- Thus a dise with 30 holes with son is a Dr. Jekyll and Mr. Hyde... produce 900 light flushes in one that there are two aides to all of revolution. The interval between us but that in most people, the the first light flash at the
second side upper
is suppressed an left hand corner of the scene and strenuously that it never crops the 900th at the lower right hand out.
corner is equal to the time it takes Estelle Taylor is one of these the disc to make one complete people. But Estelle's "other side" revolution. This is only a mall is begining to make itself known. fraction of a second. The disc has
to be kept rotating at a speed of not less than 15 revolutions a second in order to produce an ininge in the receiver which the human eye
recognize. That means 900 times 15, or 13,600 Bght flushes a second.
can
Since each light ash produces a corresponding electrical impulse In the transmitter, there would be 18,500 impulses per second going through the wires or over the radio channel used to transmit them. These impulses are referred to as frequencies.
Receiver Works Similarly.
In the receiver, a duplicate of the scanning dise on tho trana- mitiing end is made to revolve in exact synchronism with teach spiral hole cutting across the Bold where the image is being observed at exactly the same time. in the same position and, with the same speed as its corresponding hole in the, transmitting disc.
Instead of the electric eye, how- ever, the receiver has what sel- untists call a “glow (lischarge tube,"
PEA
which is made to glow brightly by Extolle, the actress, now becomes the electrical impulses that are re Estelle, the postess, whenever she calved by wire or radio from the ls away from prying eyes in the
electric eye" in the transmitter. soclusion of her own home. Thus the tube is made to glow cor- Recently Estelle was thoughtless respondingly bright and dim, and
with the same speed, as the many quick light flashes, 14,500 a "electric eye" in the transmitter second in this case. But so quick receives the light flashes.
are they that they appear as an An observer looking through the entire and recognizable Image of disc holes rotating before the glow the original scene. discharge tube, therefore, secs the By medne of lens, this original image of the televised scone flashed small image is magnified for the before him. This is actually so observer.
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Noted European artists found exotic beauty between the pages of America'a social register, as these portraits now on exhibition in New York reveal. Mrs. Edgar Scott of New York and Philadelphia is shown upper left in a colourful painting by August John. Miss Nancy Yuille, daughter of Mr. and Mrs. Thomas B. Yuille of New York, is seen upper. right in a demure pose as she appeared to Sorine, famous Russian artist. The sophisticated portrayal of Marjorie Ool. richs, lower left, is the work of Foujita, and. Savely Sorine painted the charming picture of Mrs. David Bruce, lower right, daughter of Secretary of the Treasury Andrew Mellon,
enough to reveal her "other side" by asking an opinion of a piece of pootry she had just written. Then it was learned that she avon wakes up in the middle of the night and scribbles. on, pieces of paper the thoughts which just will como bouncing Into her head,
They met with a laugh,
Changed slowly to wonder As the thrill of their handelasp Like slow moving thunder Joined two earthbound souls
With passion and squander.
So they met by the ocean
Night after night And talked with emotion
Of wrong and right Till earth in her mercy
Claimed her mito.
They'll meet by the ocean “A few youta from now, By the lack of emotion On each placid brow, That they'd never met
I don't know, Bays a writer, whether the talkies are responsible or whether Miss Taylor is just naturally that way, but anyway she has taken this fatal step However, one might entertain serious doubts as to the success of her. "other side." Estelle doesn't.
You'd be ready to vow. look like a poot. She is far too
This is just one of Estelle's beautiful, exotic and alluring.
masterpieces. She has a scrap However, that you may judge book with six or seven others in for yourselves whether the notress it. But she's keeping that well written or poet in her will predominate, hidden. She hasn't hero to the poem which she no enough poems yet to have con- fidence in herself and to tell the thoughtlessly produced at lunch world that she is a building the other day:
poetess
ད