I am still working on my plastic detector. It can't discriminate between #1 and #5 plastic. The #5 plastic produces a rainbow of colors when placed between two linear polarizes. The #1 does not. #1 randomizes the polarization and the light path and becomes clear. The effect is dramatic. I assumed that the colors in #5 came from a rotation of the angle of polarization with frequency. I tried a circular polarizer. It did not, as I had hoped, produce a detectable affect of this rotation. #5 still passes a lot of light in a rainbow of colors. All of the colors go through so that a color cap does not work. Bottles at the dump are a little dirty so that I need a robust detection technique. I need a rainbow of colors detector. I am now stuck. Where to the colors come from? Maybe I am wrong about the rotation of the angle of polarization with frequency.
I learned something useful for cold fusion. The #2 milk bottle plastic passes terahertz radiation freely. I used my motion detector light as a sensor for terahertz radiation. #2 will work as terahertz window in cold fusion experiments. Frank Z
