re: "but stating that it was not understood how the light is able to come through in some cases." Polarizers are not "filters", per se, but "re-radiators" of the EM or light waves (as the presenter in the video says, although subtly)... but, the polaizer must intercept some energy on their 'linear' segments, or elements, so the case of the 90 deg rotation then no energy is re-radiated since none was picked up, or intercepted, in the first place. That is to say, the 'elements' in a polarizer act like dipole antenna elements, with intercepted energy equal to the cosine of the angle, where cos(90) = 0.

See this collaborative explanation by Minute Physics and 3Blue1Brown kzfaq.info/get/bejne/sMmhjauK1J2zfqc.html

Note, there is a PENALTY for this "rotation", the re-radiation of the RF, I mean light EM energy is at a cost of the cosine of the angle difference from polarizer to polarizer (neglecting a small amount lost in the polarizer regardless of angle). AS long as you can sustain this cosine loss, you can infinitely rotate the light.

re: "(basically I want to know the logic behind this phenomenon ...)" Think: Re-radiation of the light at the angle of the last polarizer encountered. As long as the angle between the two is not 90 deg, then light, at the new angle, will be "radiated" by the polarizer or grating.

@@uploadJ I thought that polarizers worked by blocking light that was not at the proper polarization to pass through. All of the light passing through one polarizer should then be parallel with each other. Isn't that correct?

@@ebunny91 The light is at the angle of the **last** polarizer encountered ... nothing more, nothing less. IF the angle between two polarizers is 90 degs, then NO light makes its way through, according to the cosine of the angle, cos(90) = 0.

See this collaborative explanation by Minute Physics and 3Blue1Brown kzfaq.info/get/bejne/sMmhjauK1J2zfqc.html

@YodaWhat re: "See this collaborative explanation by Minute Physics and 3Blue1Brown" Sorry, that does not cut it. That is "obfuscation" by physicists because they THEMSELVES do not understand the simple phenomenon this actually represents.

Better to understand THIS experiment first, before jetting off into Bell's theorem and QM nonsense - I give you the microwave experiment using a simple grate: kzfaq.info/get/bejne/gbNih85-lc7eh2w.html&t=116