[Karen W. (OP)]

So when light is introduced to the pupil does the size of the pupil limit the amount of light and thus effect the vision of the beneficiary receiving this light!

I am assuming the light enters the pupil and then the retina,, Is this correct? What if your pupils are minuscule would this in effect cause you to be blind or vision impaired? I am just curious how that works..

Does the pupil size have anything to do with vision strength or weakness?

What is happening in a blind persons eyes that is different then mine? Is it simply about the lack of light entering the eye?

So when a person is blind, is it because their pupils do not dilate or open up,and allow the light in?

[RD]

Does the pupil size have anything to do with vision strength or weakness?

Smaller pupils increase depth of focus ... http://www.thenakedscientists.com/forum/index.php?topic=23576.0

So when a person is blind, is it because their pupils do not dilate or open up,and allow the light in?

There are different causes of blindness: lens damaged (e.g. cataract), retina damage, (e.g. retinopathy associated* with diabetes), damage to optic nerve or brain.

[*IMO the retinopathy common in diabetics is not cause by diabetes, I believe the retinopathy and diabetes have a common origin in vascular disease : "vascular diabetes" not "diabetic vasculopathy"].

[Karen W. (OP)]

Thanks RD.

Perhaps I should elaborate: What would happen if the pupil never opened up or dilated?