Science can take care of the monsters under your bed. Just turn the light on. Or infinite lights on with a night kaleidoscope!

The Night Kaleidoscope is a take on the wonder around the ubiquitos infinity mirror in a way that's changeable, quick, cheap, and accessible for lots of friends, family, or students to make.

This project works with the wonders of a two-way mirror. Interestingly, it's also referred to as a one-way mirror. These are sheets of acrylic with a very thin layer of aluminum in the middle that allows some light through and some to reflect. Traditionally, you light one side really bright and one really dark, and those in the bright room see a regular old mirror. Then you can film a detective TV series.

But instead we're going to make a kaleidoscope. Because they're awesome.

What: Night Kaleidoscope
Concepts: light, reflection, geometry, basic electronics
Cost: ~$3-$10, depending on box size
Time: ~30 minutes
Materials:
- Two-way mirrored acrylic (I got mine at 1/8" from TAP Plastics' scrap bin)
- Super glue
- LEDs + disc batteries
- Black electrical tape
- Acrylic glue (optional)
- Small magnets (optional)
Tools:
- Ruler + Pencil
- Bandsaw or Jigsaw
- Clamps and block of wood for jig (optional)

Let's kaleid!

Step 1: Cut the Pieces for a Mirror Box

The Mirror Box. It sounds like an long-lost ancient relic, no? Time to make some history.

Choose your own dimensions and play with it. Of course keep in mind that if you want to make a standard cubical box that not all sides will be the same size because you're gluing them end to face and they have thickness. Smaller boxes will make more reflections and are super fun. Other shapes like pyramids or dodecahedrons will make other oustanding reflections.

Mine include four panels of 4"x4" and two panels of 3.75"x4" with the material thickness of .125". I would go way smaller than this if working with a group. 2" x 2" boxes or 2" tall pyramids make pretty wonderful reflections. I made jigs using two clamps and a piece of wood, and ran the acrylic through a bandsaw. Keep the thin plastic coating on for this step.

Step 2: Glue It Up!

Acrylic glue is pretty special stuff.

Remove the coatings on both sides of your mirror, and glue together your box. With a line of glue along the edges, you only have to hold pieces there for about 15 seconds before they can support their own weight.

For the final sixth panel, it's nice if it can open and close you so can put in and take out lights. There are many solutions to this, but tape isn't one of them (it strips the mirror, see last photo). I decided to glue a set of eight very small neodymium magnets, 4 on one of the sixth panel, and the other 4 along the top of the box. If you do this, make sure the magnets are oriented so they attract so the box can stay closed.

Step 3: Make Light!

Here's the fun part, and you can play with it any way you want.

You can make LED throwies by simply taking LEDS (super bright ones are great) and taping the legs to either side of a disc battery. Black tape is great so that it doesn't reflect much.

You can pack multiple lights together, hang them from strings, put in blinkies, electronic wire, the works. You can even drill out part if you want to make a lamp with an external power source. There is no end to self-contained light magic.

Test them out in the box to see how they look, and observe the reflections. It's fascinating!

Step 4: Kaleidoscope the Night Away

Find a dark room to light up. Lights in, box top on, and you're ready to rock!

Move and rotate your kaleidoscope with your hands or let it rest to look in to its infinite reflections. A neat thing to notice is the pattern made on any surface it rests on, as a little light escapes with each reflection inside, making bands around the box. You can use this tool to learn about reflection and why images appear in the locations they do.

A couple of primer questions include:

If you put one LED in the box, in which of the six panels do you see a reflection?
If you put a scrap of two-way mirror in the box, how does this change the image?
Why are some reflections smaller than others?
Which reflections are the lightest? Which are the darkest?
Are all the reflections the same image? Or are they different?
What makes the light patterns on the table outside the box?

Play with different light sources, make new boxes with different shapes, angles, and dimensions, and you might accidentally learn about reflection along the way. :)

Have fun, and as always, keep exploring. Let me see your wonderful comments and creations below!