Retarded polarization.

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Greg Howald
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Joined: Tue Oct 20, 2020 6:44 am

Retarded polarization.

#1 Post by Greg Howald » Wed Apr 06, 2022 9:23 pm

I use polarization al lot and enjoy the view very much.
Lately I've been doing phase retardation with polarized light. In order to do this the additional filter used needs to be above the specimen but between the polarizer and analyzer. Introduction of a colored filter in this manner results in a retardation of light wavelengths between polarizing lenses and the analyzer must be rotated to reach extinction but the color of extinction will change due to retardation. So, in short, different colors cause differing amounts of retardation.

Orange, 1/4 wavelength
Yellow. 1/2
Green. 3/4
Blue 1.0

The filter used here is a 600nm yellow filter. When done you wind up with a reddish orange color.
Cheers. Greg
Attachments
phase shift one half.jpg
phase shift one half.jpg (59.13 KiB) Viewed 956 times
transmitted white 90 degrees.jpg
transmitted white 90 degrees.jpg (49.93 KiB) Viewed 956 times
transmitted white.jpg
transmitted white.jpg (62.76 KiB) Viewed 956 times

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