B
D
MATERIALS
ABS plastic pipe, 2" diameter, 15" long
Most hardware stores will cut ABS pipe to length.
ABS angled pipe coupling, 2" diameter
22½° is
ideal, but 45° will do in a pinch.
Rubber cap for 2" pipe
Hose clamp for 2" pipe
Holographic diffraction grating film,
1,000 line-per-millimeter enough to cut a
2" diameter circle; item #DIFFRACTION at Scitoys
Catalog (
scitoyscatalog.com), $3
Black construction paper, 8½"× 11"
Scrap cardboard some thin (like a cereal box or
business card) and some thicker (like a shoebox
or the back of a writing pad)
TOOLS
Digital camera
Computer with internet connection
X-Acto knife or razor blade
Ruler
Drawing compass and pencil
Glue Elmer’s white glue, Duco cement, or similar
C
E
Build a High-Resolution
Spectrograph
Time: Less Than 1 Hour
Complexity: Easy
1. Make a spectroscope.
Use a ruler and X-Acto knife to cut a straight slit
about 1¾" long through the center of the rubber
cap. Cut two ½" squares of the thin cardboard and
tuck them into opposite ends of the slit to hold it
open. The slit is now as wide as the cardboard.
Secure the rubber cap on one end of the 2" tube
with the hose clamp. Rotate the hose clamp so that
its screw is perpendicular to the slit (Figure B).
Loosely roll up the black construction paper
lengthwise and slide it all the way into the tube so it
fits neatly against the inside. This will serve to eliminate reflections. Use a compass to draw a ring on the
thicker cardboard with an outside diameter of 2" and
an inside diameter of about 13", and cut out the ring
using the X-Acto knife (Figure C). The ring should fit
inside the tube snugly but without bending.
Spread a very thin layer of glue onto one side of
the cardboard ring and affix it to the diffraction grating (Figure D). After the glue dries, carefully cut the
diffraction grating around the outside edge of the
ring using the X-Acto knife.
59 Make:
