lsd and every single other psychedelic.... its just that psychedelics change the way you think about perception, and the eye is a good symbol for that
I guess the EYE can probably represent different things for different people. My view on the EYE is a spiritual gateway. It is closely related to the Pineal Gland. Research this Gland a whole bunch and you will find it's secrets. I'm sorry but there is just too much important information to type. But that is only the scientific side of what we know. I came to function my "third EYE" with entheogens and meditation. It is a centered and special experience. It is the highlight of any trip. It's the sort of one-ness with everything EVER! Complete and absolute LOVE! (and it's such a wonder why most all religions started with the use of entheogens) I'll agree that during an entheogen it is much more intense of an experience, but it's very much rewarding everyday with meditation.
when tripping, i see eyes in things that are not eyes and i also see strange illusions concerning other people's eyes. i think the eye is just a very primal symbol and thus is evoked a lot in psychedelic imagery.
eyes are the keys to the visible universe. The third eye is used when on psychedelics to see inbetween the real world and the dream world.
when i first tripped on acid i saw a tree and it looked alive--its entire trunk was covered with EYES! lol