# Infinity Mirror

The Infinity Mirror is a cool device that uses two mirrors to bounce light back and forth to create a tunnel of light! The Infinity Mirror was part of the Monthly Make It in March, 2017.

## How It Works

An infinity mirror is a pair of parallel mirrors which create a series of smaller and smaller reflections that appear to recede into an infinite distance. We can make one using a strand of LEDs, a power source, a cardboard tube and two small round mirrors, one out of acrylic and one out of “one way mirror” film used on car windows.

### Reflectance pattern with one LED

Each time light escapes through the front mirror, less light is reflected back.

### What you see

The result is an illusion of infinite LEDS descending into the tube. Each reflection is dimmer and thus appears further back.

## How to Build It

### Step 1: Build your circuit

Take your strand of LEDS and put it inside your tube. Then push each end of the LED strand through the holes, from the inside OUT of your tube. You want your strand to be trapped inside the tube with the connector ends outside.

Now put batteries in your battery pack. (We like to remind kids to put batteries in “flat side against the spring”). Remember not to let your black and red wire leads touch while the battery pack is on or your circuit will short and your batteries will overheat!

### STEP 2: Wire it up!

In order to light up an LED strand with a battery pack, we need to connect the positive lead from the battery pack (the red wire) to the positive lead on the LED strand. The same goes for the negative [black] wire. In order to determine the “right way round” for our battery pack, we need to turn the battery pack on by pushing the metal lever on the battery pack firmly down. and touch one lead to one connector and one to the other. If the strand lights up, that is the correct configuration. If it doesn’t, we need to do it the other way around.

### STEP 3: Secure your LED strand inside the tube

Now you can secure your LED strand inside the tube. For the best effect, you want it to be equidistant between the back and front edge. Lay your strand flat and fix it to the tube with with double-sided sticky tape

### STEP 4: Attach your backing mirror

For this step we use acrylic mirror cut into circles. It usually comes with a thin film protective coating, which it’s important to remove, or else the resultant infinity mirror will look cloudy.

Now attach your mirror to your tube. It doesn’t matter which side you put it on, but you must place it mirror side in. The mirror must face towards the LED strand, into the tube. In the photos I use electrical tape to attach my mirror, however this is another step where hot glue works well.