RE: When we close our eyes are we "seeing" dark or do our eyes shutdown?
December 7, 2017 at 2:03 am
(This post was last modified: December 7, 2017 at 2:14 am by Anomalocaris.)
Your eyelids are not completely opaque. Skin and underlying fat and muscle tissues are partially translucent. Even if you close your eye lids light from outside, although attenuated and reddened by the blood vessels in the skin and muscle of your eyelids, still reaches your eyes. That’s why you can sense whether it is bright or dark outside event if you close your eyes.
Light is made up of entities called photons. You see when your retina, the light sensing tissue at the back of your eye balls, registers incoming visible light photons. In typical night time, millions of visible photons still reach your eyes per second. Experiments have shown human retina and associated optical nerve and vision center in your brain are capable of being conditioned to become so extremely sensitive it can register individual visible light photons. Let a experimental subject be conditioned to total darkness by leaving him in an absolutely light proof totally dark room for a few days. His eyes would become so sensitive you can then shine a light source at his eyes so dim and transient it only sends out a single photon. The human subject can correctly call out those individual photons as they are Emitted
You can’t even in theory be more sensitive to light than that.
However, it still takes photons for you to see. When there are no photons, the eyes do not shut down. They are still active and eagerly awaiting those photons. They simply have no photons to register.
You don’t see “dark”, true dark is the state of not seeing anything, even a stray photon.
Light is made up of entities called photons. You see when your retina, the light sensing tissue at the back of your eye balls, registers incoming visible light photons. In typical night time, millions of visible photons still reach your eyes per second. Experiments have shown human retina and associated optical nerve and vision center in your brain are capable of being conditioned to become so extremely sensitive it can register individual visible light photons. Let a experimental subject be conditioned to total darkness by leaving him in an absolutely light proof totally dark room for a few days. His eyes would become so sensitive you can then shine a light source at his eyes so dim and transient it only sends out a single photon. The human subject can correctly call out those individual photons as they are Emitted
You can’t even in theory be more sensitive to light than that.
However, it still takes photons for you to see. When there are no photons, the eyes do not shut down. They are still active and eagerly awaiting those photons. They simply have no photons to register.
You don’t see “dark”, true dark is the state of not seeing anything, even a stray photon.
