The projector uses a 1,000-watt projection
lamp, has a projection opening of 10 by 10
inches, and is equipped with a 4-1/2 inch
diameter, 22-inch focal length lens. The projec-
tor is equipped with an opaque object holding
device and a conveyor belt type loading
mechanism which permits uninterrupted projec-
tion. The projector is provided with an optical
pointer by means of which details anywhere on
the screen can be pointed out by a projected light
spot .
The roll feed assembly provides a means for
handling opaque objects of any length and up to
10 inches wide. The thickness of the objects
should not exceed one thirty-second of an inch.
The feed assembly also permits inserting and
removing the copy without lowering the platen
(figure 7-9) assembly. The maximum size of the
opaque object that can be projected at one time
is 10 x 10 inches.
To operate the roll feed assembly, stand
behind the projector and hold the crank in your
right hand. Hold the copy in the left hand, face
up, bottom edge toward the screen, and feed it
into the left side of the projector. When the
material is inserted approximately 1-1/2 inches,
turn the crank clockwise. The pressure created
by the impelled air will hold the opaque object
flat on the feed belt and when the crank is
turned, the opaque object is carried into posi-
tion. When the next opaque object is inserted,
repeat the operation. Insertion of one opaque
object automatically removes the previous one.
To project thick objects (up to 1-1/2 inches
thick), lower the platen assembly to the locked
position and remove the roll feed assembly by
lifting it off. Place the opaque object upon the
platen assembly and let it rise as far as it will go.
Apply a continuous pressure downward on the
platen handle to prevent the platen assembly
from snapping upward when you release the
lock.
Although thick physical objects (not lying in
one plane) can be projected, only one plane of
the object can be brought into focus at one time.
Other planes can be brought into focus by rota-
tion of the focusing knob. However, when an
object is not too thick, good definition can be
obtained over its entire thickness.
The projector should be positioned on a
suitable table in the projection room. The table
should be high enough to project the image over
142.122
Figure 7-9.—Nomenclature for the opaque projector.
7-20
