Concept: We can make a spectroscope using a CD instead of replica grating.
Introduction:
CD (Compact Disc) is used as a music media and a kind of computer memory media. When you look at the surface of CD under a fluorescent light or sunlight, you can see something like a rainbow. The reason is that CD has a large number of grooves (pits) on its surface at regular intervals along its radius. Namely, CD is something like a reflecting type grating. So, we can make a spectroscope using a disused CD.
Materials:
(a) A4 size cardboard (b) a disused CD (c) a black permanent marker (d) a cutter/scissors (e) wood glue (f) sellotape
Construction:
- Draw the figures of parts A, B on the cardboard as shown in Fig.2.
- Cut out the parts A, B and paint the back side of them black using a black permanent marker.3. Make two slits on the parts A and fold it as shown in Fig.2
- to make a solid body as shown in Fig.3 using wood glue.
- Put the CD into the solid bodyand fix it to the tabs of parts A using sellotape as shown in Fig.4.
- Using sellotape, attach the parts B to the tabs of parts A as shown in Fig.4
