Compound Dichroic Polarizer

Researchers at the University of Arizona have designed a device and method for converting states of polarization (SOPs) of light into separate colors. In essence, the device can code SOPs into easily distinguishable colors and color changes that are visible to the human eye, regardless of the wavelength of light illuminating the objects.

Background:
Polarizers are useful for detecting states of polarization (SOPs) in optical beams, but linear polarizers generally are neutral in color and do not permit estimation of elliptical SOPs or spectral variation in SOP.

Applications:

• Seeing polarization - Sunglasses that make polarization-blind people see polarization via false color
• Aesthetic applications - Coating for cell phones and car windows for aesthetic properties
• Polarization cameras - CDPs can convert polarization insensitive cameras to polarization sensitive cameras. This has many industrial applications, especially in manufacturing and quality control.
• Security - Since CDP color coatings are unique and complicated, they are hard to reproduce and counterfeit. This makes them ideal for verification of documents, credit cards, ID cards, and currency.

Advantages:

• Control of polarization optical properties over a wide range of wavelengths

Status: issued U.S. patent #10,901,128