Make Your Own Spectrometer
Here's a simple spectrometer you can build yourself, using just a spare CD, an empty cereal box, and a piece of aluminum foil.

Follow the directions below to see how.



Materials

What you need:

 


This is a schematic of what you'll be making:


 

1. On the top of the box, measure in 1.5 inches and make a mark.

 

2. Using the 90 degree edge of the triangle...draw a guideline across the width of the box.


 

3. Cut along the guideline, then unfold the flaps you just made. Cut off the flaps.


 

4. Place the short edge of the triangle along the top edge of the box and draw a 3 inch line towards the center of the box: Using those lines as guides...cut two 3" slits on both sides of the cereal box as shown.

 


5. Flip the box over and do the same thing on the other side.  

 

6. Slide the cd into the slits as shown

 

7. Now you're going to cut a rectangle out on the opposite long side of the box as shown. The rectangle should be the width of the box and one inch high. The top of the rectangle should be about half an inch from the top of the box.

To cut it, first poke a hole towards the top of the box with a pen. Then, cut a rectangle using the hole as a starting point.



8. Take enough aluminum foil to cover the hole and fold it in half. place the creased side towards the middle of the hole and tape it in place.
9. Take a second piece of foil and cover the bottom half of the hole. You want to leave a gap between the two pieces of foil. This gap should be between .4 and 1mm. Too wide and the spectra gets blurry. Too narrow then not enough light gets in.
10. Tape the top of the box closed.
8. Point the slit at a bright light bulb, and look into the square hole.

You should see something like this:

Here are some other light sources you can look at:

Sun
DO NOT LOOK DIRECTLY AT THE SUN. Point your spectrometer to a white wall in sunshine or at some clouds instead.
Candle
Fluorescent Light Bulb
Mercury Vapor Lamp
Sodium Lamp
Notice the bright yellow area and the large gap between the green and light blue?

With your simple spectrometer, you can see a few interesting light sources. But, it would be nice to see the spectra of many things that aren't easily found in your neighborhood.

Luckily, Whyville has built a spectrometer to help.

Explore the Whyville Spectrometer.