Step by step instructions for building your own device to look for polarization in materials, we use this for testing optical elements and but it's also commonly used by gemologists.

Supplies

Components

-An old display such as a cell phone LCD

-Powering microchip

-USB cable

-Powered USB port (3-5 V)

-Polarized film or 1/4 wave film (can be cut from an old cell phone or laptop)

-Magnifying lens

-Test film

Tools
-Soldering iron

Step 1: Obtain a Display Screen

You can use a new LCD screen or remove one from an old cell phone.

Step 2: Power the Display Screen

Find the leads that power the screen backlight and solder a USB cable to the leads. Plug the other side of the cable into a 3-5 V powered USB port.

Step 3: Obtain a Polarized Film

You can cut the polarized film from an old cell phone, laptop, or any LCD display or purchase a 1/4 wave film from

Step 4: Purchase Magnifier

Walmart sells one similar to the one we used

Step 5: Assemble Film, Screen and Magnifier

Place the polarizing film above the magnifying lens and the cell phone screen below the lens. Try assembling without the polarizer film to see the light blocking effect of the polarizer.