Physics Asked on December 19, 2020
The phenomenon is:
A semi-opaque semi-rigid plastic sheet covers a window, if you see the sheet directly from any direction, there is no iridescence on the sheet. But if you see the sheet through a smooth reflective surface, there is iridescence on the sheet. Tested reflection surfaces are highly reflective ceramic tile/smooth plastic object/phone front panel(which is glass). But mirror doesn’t show iridescence on the sheet.
The iridescence is on the plastic sheet, not on the window that is not covered or the reflective surface itself (based on the distance of the iridescence from eye and wiping the surface doesn’t change the iridescence pattern)
When and how deos this happen? Since it is related to reflection, it may be related to polarization, but how?
You are seeing polarization effects. Light reflected from smooth dielectric surfaces at an angle of about 57 degrees from normal is higjly polarized. The plastic sheet has slightly different refractive index in different directions, usually because it was stretched during manufacture. Light passing through the plastic sheet has its polarization rotated according to wavelength and angle. So the smooth glassy surface and the surfaces of the plastic film both act as polarizing filters. You can get a polarizing filter from a camera store or srom a science hobbiest supply and confirm this.
Correct answer by S. McGrew on December 19, 2020
Get help from others!
Recent Answers
Recent Questions
© 2024 TransWikia.com. All rights reserved. Sites we Love: PCI Database, UKBizDB, Menu Kuliner, Sharing RPP