Movies for TV - Early Television Foundation

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FUNDAMENTALS
Next is the fourth section which contains the equipment for con-
trolling the functioning of the television cameras, and finally comes
the fifth section which is comprised of the cameras themselves.
Sound is transmitted also, but since we are concerned with the visual
side of television, only
a brief reference will be made to it.
The Television Camera A picture has to be transmitted in
small parts, one at a time. The reason for this is quite involved and
is controlled by the electrical characteristics of radio equipment.
When the human eye observes a scene, the rods and cones which
constitute the retina operate in such a fashion that the cones sense
the colors and the rods are affected by black and white (this, in-
able to see better in the
cidentally, is the reason for a person being
dark if he turns his head away from a direct, full-front view of the
object the rods are at the sides of the retina and consequently are
able to function better than when more in front of the scene). The
combination of rods and cones forms a mosaic on which the scene
is focussed by the pupil. The mosaic is just what its name implies
an area of thousands of minute cells each of which is connected to
the brain and receives an extremely small part of the picture. When
the impressions from the whole mosaic have been received by the
brain, it "sees" the whole picture (of course,
taneously ) .
this occurs instan-
If it could be arranged in television so that an electric eye could
see the entire picture to be transmitted and send it all at once, or
nearly so, to the receiver where it would be seen on a similar screen,
there would be no problems of definition. Unfortunately, this cannot
so far be done since the transmitter would require literally thou-
sands of frequencies, each one for a separate transmitter, together
with the same number of cells at the receiving end as well. It has
been attempted in fact, one of the earliest research workers de-
veloped a system whereby wires connected the transmitting cells
to the receiver but it had low definition and was too complex.
The illuminated signs, which consist of a bank of electric light bulbs
with various of them becoming illuminated in accordance with the
master key, are a form of television, but a metallic key instead of