If two polarizers are placed 90 degree rotated to each other, we won't be able to see anything. But when I tried looking directly at sun, which I did only for a second, with that perpendicular pair of polarizers, I was still able to see the sun. Shouldn't the sun disappear too ? Or why is it am able to see the sun ? Similarly it's applicable when I look at a strong source of light, like tube light or CFL bulbs.