Polarized Light Sensor
This work was inspired by Elena Cruz, a scientist working in the Museum of Science's Butterfly Garden
Insects, such as butterflies, see polarized light, but rather than use the entire spectrum that they capable of seeing, they appear to use certain wavelengths (blue, mostly) of polarized light to recognize their mates, find healthy plants to eat, and decide where to lay their eggs. With expensive equipment, we could simulate what insects see, but with little money, we can explore our surroundings for polarized light.
A digital camera is a useful tool to explore polarized light at various wavelengths. A digital camera:
"sees" from the ultraviolet to the near infared,
measures three colors at the same time in the visible light range,
can be used with a polarizing filter, and
can be placed in movie mode while the polarizing filter is turned.
More detailed work can be done by taking individual photographs as you rotate the polariizer. Use AnalyzingDigitalImages software to separate color layers and/or compare color layers (and a second example with digital photographs) and save the new visualizations and make a movie from the new images with QuickTime Pro ($30 upgrade to Apple's free QuickTime). AnalyzingDigitalImages is available as part of the DEW software bundle.
Explore the movies that follow to develop ideas for your own explorations.
Resources about Polarized Light
On-Line Tutorial (High school level)
How Stuff Works – Sunglasses
Advanced high school to college level
Polarization of Butterfly Wings – Explore the effect of viewing the wings at different angles:
Polarization of Plant Leaves (and flower pots...)
Polarization of the Sky – Visible Light or Near Infrared
Back to Tools and Technologies