How Does Our Eye Works and How Eye Color Affects Eyesight?
abe...@gmail.com
p.cl...@gmail.com
> please help me !!!!!
you've got to be kidding! you expect someone to write a brief
paragraph on "how our eye works"? You are just going to have to do
some reading and studying for yourself. It's a little complicated and
the information is very accessible. good luck.
PS -- eye color (=iris color) has virtually nothing to do with how the
eye functions. its kind of like skin color-- no matter how dark or
light a human's complexion is, their body works the same as everyone
elses.
Zetsu
light colour then you might be more succeptible to skin burning.
Zetsu
>How Does Our Eye Works and How Eye Color Affects Eyesight?
The eyes detect light, and then the light get interpreted in the mind.
The working of the eye has been studied; but less is known of the
mind.
You can read the big descriptions in medical journals and whatnot.
But if you are lazy and can't be bothered for that, just read a round
the various internet sites, e.g. wikipedia, and other encyclopedias.
If you keep reading through the encyclopedias you'll become a master
of the working of the eyes, but you have to study it and even that
takes quite long. If you are casually learning, then it might take you
a month. If you want to know everything that is currently known, that
will take longer, say: a year or two.
Mike Tyner
"Zetsu" <absolutely...@hotmail.com> wrote
> Well skin colour affects how your body works because if you are a
> light colour then you might be more succeptible to skin burning.
And your eyes may be more sensitive to light.
But what measure of "vision" is better or worse in light or dark eyes?
Vernier acuity? Stereopsis? Color? Pursuits? What?
As a matter of fact, albinos often do have problems in those areas.
But normally, blue and brown eyes don't differ significantly in any measure
of "vision" except subjective light sensitivity.
-MT
Zetsu
I was talking about skin colour, because that was the wrong analogy
used by the other poster, remember. I was pointing out why that
analogy is not correct.
>But normally, blue and brown eyes don't differ significantly in any measure
>of "vision" except subjective light sensitivity.
Oh okay, what about hazel colour?
Also, if you were contact lenses to change your colour, does that mean
that the subjective light sensitivity changes too?
Also, what happens if you have greater light sensitivity?
Does it means you can see better in the less light?
Or would the difference not be noticable?
Mike Tyner
"Zetsu" <absolutely...@hotmail.com> wrote
> Oh okay, what about hazel colour?
You didn't know. Blue, hazel, green or brown all result from one pigment.
Blue and brown are the extremes.
> Also, if you were contact lenses to change your colour, does that mean
> that the subjective light sensitivity changes too?
Contacts must be pretty dark to have that effect. None of the popular
"cosmetic" colors are dark enough to work as sunglases.
The subjective light sensitivity is usually attributed to lack of pigment
_behind_ the iris. Even in blue-eyed people, the back of the iris is brown.
The retina is pigmented. It's slate-gray in black people, pale and
transparent in blondes. This internal pigment acts as a light baffle, for
the same reason the inside of a camera is painted matte black. When the
retina and iris are pale, light bounces more, reducing contrast and
diminishing subjective comfort in bright light. In the extreme, this
probably does reduce contrast and therefore a small effect on acuity.
> Also, what happens if you have greater light sensitivity?
> Does it means you can see better in the less light?
No it means you complain more about sunlight.
> Or would the difference not be noticable?
If you measure acuity, there's not much difference between one iris color
and another. For _retinal_ color, there's probably a small difference in
very bright light where scattered "glare" can reduce contrast.
-MT
Zetsu
Thank you very much.
>Contacts must be pretty dark to have that effect. None of the popular
>"cosmetic" colors are dark enough to work as sunglases.
What if the contacts were not cosmetic?
I mean, could you make them so they change colour sensitivity?
Mike Tyner
"Zetsu" <absolutely...@hotmail.com> wrote
> I mean, could you make them so they change colour sensitivity?
Could you make contacts dark enough to work like sunglasses?
Sure you could, but you wouldn't sell many.
You could just switch to another pair when you drive into a tunnel or walk
in out of the sunlight.
-MT
Zetsu
(As in, opposite of sunglasses).
t1ge...@hotmail.com
> Can you make them so that they increase colour sensitivity?
>
> (As in, opposite of sunglasses).
You should look at www.nikevision.com they have some interesting
information about contacts that control light while doing various
activities. They don't work just like sunglasses but it is fairly
interesting.
p.cl...@gmail.com
>
> I was talking about skin colour, because that was the wrong analogy
> used by the other poster, remember. I was pointing out why that
> analogy is not correct.
>
my analogy was meant from a "50,000 foot view". meaning that in a
very general sense, eye color has nothing to do with how the
photoreceptors absorb light, transduce the signal and process it
through various nerve cells, and send it to the brain for even higher
image processing and interaction with other conscious processes.
of course in a detailed sense there are indeed some effects of iris
color but that is not the level of discussion the original poster is
wanting. and as far as the analogy to skin color, it still seems
pretty appropriate since skin color does indeed cause small
differences in the physiology of the human body but not in the overall
mechanisms of respiration, circulation, locomotion, etc.
the reader needs to do some studying on his own, and I would say that
more than a year or two is required to "know everything". i've been
researching and working in the field for 25+ years and I don't know
everything. neither does anyone else.
Zetsu
Well I don't mean know everything, like everything there is, I just
mean everything that's been found it in the field. Of course it is
impossible to know everything! No one can know everything, lots of
research needs to be done first. Also I agree the reader needs to do
some studying on his own, but it seemed he was just looking for a
general idea; so he should go on the encyclopedias which will give him
the general ideas. Do you know what I mean though?
>pretty appropriate since skin color does indeed cause small
>differences in the physiology of the human body but not in the overall
>mechanisms of respiration, circulation, locomotion, etc.
Malignant melanoma can cause DEATH though!
Jan
> You should look at www.nikevision.com they have some interesting
> information about contacts that control light while doing various
> activities. They don't work just like sunglasses but it is fairly
> interesting.
>
They are not controlling light, they just filter a particulary area of
visible light.
Jan Oudesluys (normally Dutch spoken)
Neil Brooks
trolls who haunt s.m.v.
Rishi has published, and is trying to sell worthless books.
Otis is pathologically dishonest and actually hurts people.
Following his advice can induce double vision in those
not working closely with an eye doctor.
Lena102938 uses anti-eye doctor rhetoric as a substitute for ANY
actual information. It seems she now has to wear glasses and has
developed a pathological (and ILLOGICAL) resentment toward the
industry that "foisted these glasses upon her."
You'd do well to ignore them and wait for responses from the
caring, compassionate eye doctors who DO also participate in this site.
Father Mike
> please help me !!!!!
I smell a homework assignment!