When two polarizing filters are placed atop one another, they can be transparent or opaque to light. By rotating one of the filters, the transmitted light passing through the filters may be turned 'on' or 'off'. Certain materials such as polyethylene, cellophane tape, plexiglass, and corn syrup can exhibit beautiful colors when placed between two polarizing filters.
These high quality plastic polarizing filters are perfect for all kinds of experimentation. Can be cut with scissors or an ordinary paper cutter. Sold individually.
Available in various sizes. (Sizes are approximate.)
Please note: Our polarizing filters originate on a large roll and may be slightly curved when you receive them. If you need a filter to lie flat, you can bend it in the opposite direction to flatten it and/or place it between two heavy flat surfaces, such as text books.
Download the pdf of this lesson!
When two polarizing filters are placed atop one another, they can be transparent or opaque to light. By rotating one of the filters, the transmitted light passing through the filters may be turned 'on' or 'off'. When the filters do not transmit light, the polarizing filters are said to be 'crossed polarizers'. Certain materials such as cellophane tape, Plexiglas, corn syrup, and stretched polyethylene exhibit beautiful colors when placed between two crossed polarizing filters.
- Place a piece of mica between two crossed polarizing filters. Each color represents a different thickness of the mica. Try rotating one polarizing filter. Try rotating the mica.
- When a piece of Plexiglas is placed between two crossed polarizing filters and squeezed, stress lines appear. Engineers use this method to discover the stress areas in new structural designs.
- Place a piece of polyethylene between two crossed polarizing filters. Then stretch the polyethylene by pulling it. Examine the stretched polyethylene sheet between the crossed filters.
- Use the special cellophane tape to create designs on a sheet of acetate. Then examine the results by placing it between two crossed polarizing filters. Rotate one of the filters.
- If you look at the words on a printed page through a crystal of calcite, you will see double. These natural, nearly transparent crystals exhibit the property of 'birefringence', i.e. they break light into two distinct polarized beams. By rotating a polarizing filter over the crystal, it is possible to view one image at a time. This phenomenon can be displayed using an overhead projector.
Only vertically oriented light waves may pass through the polarizing filter on the left. Only horizontally oriented light waves may pass through the filter on the right. If the filter on the left is placed on top of the filter on the right, no light will be able to pass through at all.
If the polarizing filters are aligned parallel to each other, light may pass freely through both filters. By placing transparent objects between two polarizing filters, it is possible to identify those materials which rotate polarized light!
Try sandwiching a plastic baggie between two filters and stretching it. When certain plastics are put under stress, they rotate polarized light. Try placing transparent tape between two polarizing filters. Some brands of tape work better than others. The more layers of tape, the more light is rotated.
Write a review
Has Protective Plastic.
Oct 25, 2016 | By Melissa of Sandpoint, ID United States
Apr 20, 2016 | By Jeff Erickson of Vacaville, CA United States
Mar 14, 2016 | By Martin ward of C.b.s, NL Canada
Owner Response:These can be cut to almost any size. Just call our customer service line, and we can get the order right out.
Mar 10, 2016 | By Rebecca Griffey of Davis, CA United States
Feb 29, 2016 | By Rebecca of David, CA United States
Owner Response:Rebecca, someone from our customer service department will be in touch with you. I'm guessing that perhaps you have not removed the protective plastic that covers all our filters when they ship. If the actual filters are truly scratched, then we will certainly replace them at no cost to you.
Dec 28, 2015 | By Lynne W of Baton Rouge, LA United States
Mar 8, 2015 | By Bob Burruss of Bethesda, MD United States
May 15, 2013 | By Milton of Downingtown, PA United States
Polarizer films 6 x 6
Oct 12, 2012 | By Frank Yepez of Dallas, PA United States
Above & beyond
Jun 25, 2012 | By Mae of Mississauga, ON Canada
This product will support your students' understanding of the Next Generation Science Standards (NGSS)*, as shown in the table below.
Suggested Science Idea(s)
Students can use this tool to conduct an investigation of how different materials affect the path of a beam of light.
Students can use Polarizing Filters to develop and use a model to describe how waves are reflected, absorbed, or transmitted through various materials.
Students can use Polarizing Filters to conduct investigations and use mathematical representations to support a claim regarding relationships among the frequency, wavelength, and speed of waves traveling in various media.
Students can use Polarizing Filters to experiment and model how light waves are altered when transmitted through various materials.
* NGSS is a registered trademark of Achieve. Neither Achieve nor the lead states and partners that developed the Next Generation Science Standards were involved in the production of, and do not endorse, this product.