Elenco LIGHT - Manual (Page 48)

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Project 82 LED Color Spectrum Project 83
LED Color
Spectrum (II)
Use the preceding circuit, but remove the 2-snap
across points W-W and place 2-snaps across R-R
and G-G. Use the prismatic film to look at the color
spectrum. View from different directions and
different angles.
Next, move the 2-snaps to R-R and B-B, and look
at the spectrum. Then move the 2-snaps to G-G and
B-B and look at the spectrum. View from different
directions and different angles.
For each combination, the color spectrum should
be mostly light of the 2 individual colors you are
combining.
Build the circuit as shown, and turn
on the switch (S1). The white LED
(D6) will be on. Look at the white
LED through the prismatic film to see
the color spectrum of white light,
which is all the colors of a rainbow.
For best effects, do this in a dimly lit
room.
Now remove the 2-snap across
points W-W, and place it across
points C-C (the color LED), then
points R-R, G-G, and B-B (for the
color organ). Using the prismatic film,
look at the color spectrum produced
by the color LED, and the different
colors from the color organ.
Compare them to the white LED
spectrum.
Project 84
LED Color Spectrum (III)
Use the preceding circuit, but place 2-snaps across points R-R, G-G,
and B-B. Use the prismatic film to look at the color spectrum. View from
different directions and different angles.
With the above connections, the color organ (U22) produces white
light. The actual color spectrum you see will vary with your viewing
angle, because the light is produced using separate red, green, and
blue LEDs next to each other.
Now remove the 2-snaps from R-R, G-G, and B-B, and place one
across W-W, so the circuit is like the project 82 drawing. Use the
prismatic film to view the color spectrum from the white LED (D6)
again, and compare it to the white light spectrum from U22. The D6
spectrum does not vary as much with the viewing angle because the
light is produced by a single LED, and it is brighter.
Project 85
LED Color Spectrum (IV)
Use the circuit combinations from projects
82-84, but look at the different lights through
the red, green, or blue filters instead of the
prismatic film. Each filter only allows you to
see light of that color, and blocks the other
colors. If you put all three filters together
then all light is blocked.
Actually, the red filter will pass a little of the
green light, the blue filter will pass a little of
the green light, and the green filter will pass
a little of the green and blue light. This is
because green light is between red and blue
light in the color spectrum, and the filters are
not perfect. See page 13 for more
information about the color spectrum.
Project 86
LED Color
Spectrum (V)
Repeat project 82, but place
the black fiber optic cable
holder with the fiber optic
cable on the LED you want
to view. Look at the light
coming out the other end of
the cable using the prismatic
film, and view in a dimly lit
room. The light is not as
bright but the beam is
narrower, so the color
spectrum may be clearer.