Movies for TV - Early Television Foundation

COLOR 169
mitted. The system is sequential in that only one color at a time
is presented. Persistence of vision and screen afterglow cause the
colors to combine and produce the various shades.
Color Television, Inc. This system shows promise but as yet
is an unknown factor in the color stakes. Theoretically, it is cap-
able of excellent results. In essence, the main features of the system
are the use of stationary filters in conjunction with a three-lens
optical system at the camera and receiver. At the receiver, superposing
lenses are used to register three images, each through a
different primary color on the screen of a single cathode-ray projection
tube onto a projection screen. Standard black and white
equipment is modified in one major respect the horizontal scan-
ning frequency is only one-third of the normal frequency, since
each scanning line traverses three edge to edge fields in succession.
Such a change is a simple one. Three equi-spaced synchronizing
pulses are applied during the interval of one horizontal scan, ar-
ranged to lock into operation so that each color is flashed at the
correct time, and the pictures will show up as black and white
views on an ordinary receiver without difficulties. Horizontal
linearity must be precisely attained.
The camera system consists of a standard black and white
single image orthicon camera with a multiple image lens and filter
system. Three optical images are focussed side by side and scanned
as though they were a single image. The video signals generated
are transmitted in the normal manner to standard black
and white amplifier and mixing equipment. Standard black and
white, line, frame, and super-synchronizing pulses, are used to
control the system. The colored pictures are reproduced from 525
line images in each filter color, with 10 color pictures per second
and 60 color interlaced fields per second.
Radio Corporation of America This system utilizes the full
width of the television transmission band and puts out a signal of
525 lines, the same as the present black and white transmission.
This means that the theoretical quality is of a very high order.