Polarizer Detector
(A Source of Polarized Light)
Most cellphone screens utilize polarizers to allow users to see what the cellphone wants them to see and not extraneous glare and reflections. What this means is that the light emitted from your cellphone is polarized light. Ergo, you have your own polarization detector, too. This emitted polarized light can become unpolarized though as it passes through a screen protector, so to see this effect, you may need to lift your screen protector. You can now verify whether or not those sunglasses are really polarizers or not, by looking through one lens of the glasses at your cellphone screen. Simply rotate the lens (or phone) and see if light becomes blocked. Since most glare is horizontally polarized, polarized sunglasses have their polarization axis vertical. Knowing this, you can determine the polarization axis of your cellphone screen, which could then help you determine the polarization axis of another polarizer later. You can also now insert different transparent objects in between your cell phone screen and your polarized sunglasses and see if the object affects its transmitted polarized light or not. Here is a picture of the
stresses seen in a pair of normal eyeglasses.
(A Source of Polarized Light)
Most cellphone screens utilize polarizers to allow users to see what the cellphone wants them to see and not extraneous glare and reflections. What this means is that the light emitted from your cellphone is polarized light. Ergo, you have your own polarization detector, too. This emitted polarized light can become unpolarized though as it passes through a screen protector, so to see this effect, you may need to lift your screen protector. You can now verify whether or not those sunglasses are really polarizers or not, by looking through one lens of the glasses at your cellphone screen. Simply rotate the lens (or phone) and see if light becomes blocked. Since most glare is horizontally polarized, polarized sunglasses have their polarization axis vertical. Knowing this, you can determine the polarization axis of your cellphone screen, which could then help you determine the polarization axis of another polarizer later. You can also now insert different transparent objects in between your cell phone screen and your polarized sunglasses and see if the object affects its transmitted polarized light or not. Here is a picture of the
stresses seen in a pair of normal eyeglasses.