 |
|
| Science Forum Index » Medicine - Vision Forum » Color Correcting Lens Coatings?... |
|
Page 1 of 1 |
|
| Author |
Message |
| Joe... |
 Posted: Fri Nov 06, 2009 1:32 pm |
|
|
|
Guest
|
I haven't visited this ng in a few years, but...
A number of years ago, I remember reading about a new development that
would allow (partially?) color blind people to discriminate colors
better. I believe it used thin film coatings to selectively attenuate
the dominant colors, allowing for a better color balance.
Has anything else happened on this front? I suppose the original
inventor went by the wayside, but the concept is good. The biggest
drawback I can imagine would be the fragility of the coating.
I was reminded of the idea last week while on a drive in the
mountains. I own a pair of copper-flashed blue blocker clip-ons, and I
could really enjoy the fall foliage. When I removed the clip-ons, the
red colors disappeared almost entirely, and the yellows were dulled.
It would be nice to see a more accurate color mix with my regular
glasses.
Joe |
|
|
| Back to top |
|
|
|
| Lelouch Lamperouge... |
| Posted: Fri Nov 06, 2009 1:32 pm |
|
|
|
Guest
|
On 6 Nov, 18:41, "Mike Tyner" <mty... at (no spam) mindspring.com> wrote:
[quote]It's no cure.
[/quote]
YOU SAID IT DOC. |
|
|
| Back to top |
|
|
|
| Mike Tyner... |
| Posted: Fri Nov 06, 2009 1:41 pm |
|
|
|
Guest
|
"Joe" <see_real_one at (no spam) sig.lin> wrote
[quote]It would be nice to see a more accurate color mix with my regular
glasses.
[/quote]
You have a curious definition for "accurate."
Take a photo through your copper-flashed blue-blockers.
Color blindness has been treated by using a red filter in one eye. This
patented process doesn't modify the "color balance" but instead creates a
trick of perception where colors can be distinguished somewhat better. It's
no cure.
-MT |
|
|
| Back to top |
|
|
|
| Joe... |
| Posted: Fri Nov 06, 2009 3:12 pm |
|
|
|
Guest
|
On Fri, 6 Nov 2009 12:41:56 -0600, "Mike Tyner"
<mtyner at (no spam) mindspring.com> wrote:
[quote]
"Joe" <see_real_one at (no spam) sig.lin> wrote
It would be nice to see a more accurate color mix with my regular
glasses.
You have a curious definition for "accurate."
[/quote]
No, if I am deficient in my ability to see red, then either by
increasing the "amount" of red, or by decreasing the non-red, the
color balance would be more accurate *as perceived by me*.
[quote]
Take a photo through your copper-flashed blue-blockers.
[/quote]
OK, I don't have a camera handy, but I expect to see a decrease in
blue (which should make the blue "darker", trending to being dark gray
to black), which would cause other colors to be more predominant (in
the mix).
[quote]
Color blindness has been treated by using a red filter in one eye. This
patented process doesn't modify the "color balance" but instead creates a
trick of perception where colors can be distinguished somewhat better. It's
no cure.
And whites would look red - definitely not a cure.[/quote]
So how do my clip-ons work? My original "test target" was an old Coke
sign (red on black). I could not distinguish the letters from the
background, but with the clip-ons, the contrast was excellent, and the
red looked red. Green lawns look brighter green. Yellows seem about
the same, but the blue skies look dark gray - clouds still appear
white, though. It may be a "trick of perception", but I can
distinguish colors a *lot* better. It's like a whole new outdoor world
to me, and is as good a cure as I'm likely to get in my lifetime.
My wife, who has normal color vision, is totally unimpressed with the
view though my glasses.
Joe |
|
|
| Back to top |
|
|
|
| Salmon Egg... |
| Posted: Fri Nov 06, 2009 5:23 pm |
|
|
|
Guest
|
In article <h4q8f5t2v47q8d5pe64kkg8bv5l6uj50od at (no spam) 4ax.com>,
Joe <see_real_one at (no spam) sig.lin> wrote:
[quote]I haven't visited this ng in a few years, but...
A number of years ago, I remember reading about a new development that
would allow (partially?) color blind people to discriminate colors
better. I believe it used thin film coatings to selectively attenuate
the dominant colors, allowing for a better color balance.
Has anything else happened on this front? I suppose the original
inventor went by the wayside, but the concept is good. The biggest
drawback I can imagine would be the fragility of the coating.
I was reminded of the idea last week while on a drive in the
mountains. I own a pair of copper-flashed blue blocker clip-ons, and I
could really enjoy the fall foliage. When I removed the clip-ons, the
red colors disappeared almost entirely, and the yellows were dulled.
It would be nice to see a more accurate color mix with my regular
glasses.
Joe
[/quote]
I am not a vision professional.
You do not state if you are color blind or what kind of color capability
you do have. Presumably, my guess would be that you are missing one kind
out of three kinds of cones. It is true that a color filter could make
it possible to tell the difference between two colors that are confused
with each other. You can expect such a filter to nake other pairs of
colors indistinguishable.
I would expect that there would be very little new available to help
out. The technology of thin-film filters was well worked out decades
ago. There is enough information available so that it is fairly
straightforward to figure out, with a bit of calculus and modest
computer power. which colors would be easily confused for a given kind
of color blindness when a particular kind of filter is used.
Bill
--
As the years go by, dying just before having to fill out a tax return has merit. |
|
|
| Back to top |
|
|
|
| Liz... |
| Posted: Fri Nov 06, 2009 8:36 pm |
|
|
|
Guest
|
[quote]Color blindness has been treated by using a red filter in one eye. This
patented process doesn't modify the "color balance" but instead creates a
trick of perception where colors can be distinguished somewhat better.
[/quote]
Fascinating!!! I think this is what birds do (bear with me). They
have drops of colored oil in each cone, which sharply cuts off the
spectrum it can pick up on one side of its curve. This is supposed to
allow the bird to distinguish more colors, or different colors more
easily. It must only work if the brain somehow sorts the input from
each kind of cone...
[quote]And whites would look red - definitely not a cure.
[/quote]
I think it would only let you distinguish them because you have two
eyes and are getting different input from each. If you put the same
thing over both eyes, it might not work. If you then integrated the
two images, I'd expect whites to have a pink cast... or whatever you
see as pink.... (sorry, this is really interesting).
It sounds like your glasses are doing whatever they do in some other
different way, perhaps by enhancing some colors and dimming others.
This would produce an artistic effect as well as a practical one.
I'm with your wife - I distinguish colors less well through amber
sunglasses.
You might be able to get clear glasses tinted to many different
colors. A company called BPI makes all kinds of lens dyes that (I
gather) one's optician can order for lenses. Probably expensive.
cheers,
Liz
(wishing I could see like a bird) |
|
|
| Back to top |
|
|
|
| Joe... |
| Posted: Fri Nov 06, 2009 8:50 pm |
|
|
|
Guest
|
On Fri, 06 Nov 2009 14:23:02 -0800, Salmon Egg
<SalmonEgg at (no spam) sbcglobal.net> wrote:
[quote]In article <h4q8f5t2v47q8d5pe64kkg8bv5l6uj50od at (no spam) 4ax.com>,
Joe <see_real_one at (no spam) sig.lin> wrote:
I haven't visited this ng in a few years, but...
A number of years ago, I remember reading about a new development that
would allow (partially?) color blind people to discriminate colors
better. I believe it used thin film coatings to selectively attenuate
the dominant colors, allowing for a better color balance.
Has anything else happened on this front? I suppose the original
inventor went by the wayside, but the concept is good. The biggest
drawback I can imagine would be the fragility of the coating.
I was reminded of the idea last week while on a drive in the
mountains. I own a pair of copper-flashed blue blocker clip-ons, and I
could really enjoy the fall foliage. When I removed the clip-ons, the
red colors disappeared almost entirely, and the yellows were dulled.
It would be nice to see a more accurate color mix with my regular
glasses.
Joe
I am not a vision professional.
You do not state if you are color blind or what kind of color capability
you do have. Presumably, my guess would be that you are missing one kind
out of three kinds of cones. It is true that a color filter could make
it possible to tell the difference between two colors that are confused
with each other. You can expect such a filter to nake other pairs of
colors indistinguishable.
[/quote]
I have "red-green" color blindness (protanomaly?). In every test I've
taken (the Ishihara tests) I fail the red-green part; even if someone
tells me the answer, I can't see it - at all. However, I *do* see red
& green (green does OK). Red is the biggest problem, especially if the
lighting is low. I absolutely can't see the red colors of the foliage
during a drive (I do better if I'm standing right next to a dogwood,
e.g.). With the clip-ons, the colors just jump out at me - at least
comparatively speaking. Only blue suffers. Clever folks who make their
web pages red on black produce entirely black pages for me; although I
can see a blush of red, I cannot see enough to discern any letters at
all. I'm an electronic technician, BTW, so it has been a bit of an
issue, especially in the past.
[quote]
I would expect that there would be very little new available to help
out. The technology of thin-film filters was well worked out decades
ago. There is enough information available so that it is fairly
straightforward to figure out, with a bit of calculus and modest
computer power. which colors would be easily confused for a given kind
of color blindness when a particular kind of filter is used.
[/quote]
The information I had seen a few years ago may have been pure hype,
but I inferred that it was interference filter layers tailored to an
individual's color shortcomings. Made sense at the time, the trick may
have been the ability to coat lenses on a one-off basis
(economically).
Also see my previous reply.
Joe |
|
|
| Back to top |
|
|
|
| Mike Tyner... |
| Posted: Fri Nov 06, 2009 11:02 pm |
|
|
|
Guest
|
"Joe" <see_real_one at (no spam) sig.lin> wrote
[quote]
You have a curious definition for "accurate."
No, if I am deficient in my ability to see red, then either by
increasing the "amount" of red, or by decreasing the non-red, the
color balance would be more accurate *as perceived by me*.
[/quote]
That's logical but it's not as helpful as you might like, for "accurately"
distinguishing one sock from another, or for reproducing a pattern like
this:
http://www.normankoren.com/ColorChecker_sRGB.jpg
[quote]And whites would look red - definitely not a cure.
[/quote]
Remember I said red filter in *one eye*.
[quote]It's like a whole new outdoor world
to me, and is as good a cure as I'm likely to get in my lifetime.
[/quote]
That's a subjective perception, an esthetic judgement. Attributes like
"accurate" don't really apply. Subjective perceptions are plenty susceptible
to hype.
[quote]My wife, who has normal color vision, is totally unimpressed with the
view though my glasses.
[/quote]
Many people with normal vision are impressed by the "blue-blocker" effect.
It's why shooters wear yellow. But the only measurable improvements occur
because the spectrum is *reduced*.
The color tests given by the FAA and the military and the phone company
don't show much improvement with binocular filters.
-MT |
|
|
| Back to top |
|
|
|
| Salmon Egg... |
| Posted: Sat Nov 07, 2009 12:22 am |
|
|
|
Guest
|
In article <dqi9f5hjp2hki2v8ahidf19d6fp0k1vv2s at (no spam) 4ax.com>,
Joe <jgandalf1 at (no spam) gmail.com> wrote:
[quote]The information I had seen a few years ago may have been pure hype,
but I inferred that it was interference filter layers tailored to an
individual's color shortcomings. Made sense at the time, the trick may
have been the ability to coat lenses on a one-off basis
(economically).
[/quote]
My understanding of color vision is based upon Maxwellian three-color
theory. Although developed over a century ago, this theory has been
augmented but not fundamentally changed over the years.
Normal color vision involves three kinds of cones. Each kind has a
different visual pigment and each kind generates nerve impulses in
proportion (roughly) to how much light gets absorbed by that pigment.
With the three pigments, there are three signals that get sent to the
brain. It is the ratios amongst those signals that the brain interprets
as color,
Because it is impossible for me to know how you perceive a color, most
experiments on color perception are based upon matching of colors. You
might throw in wether a color would have to be redder or bluer to match
a color, only the matching gives an objective result.
In your (Joe) case you only have two kinds of visual pigments. All a
filter can do is to take two colors that appear match to you and distort
the color to where they do not match. It would also be possible to take
colors that do not match and use a filter to make them match. That would
make it possible for you to distinguish traffic signals from one
another, but that can be done in other ways. For example, the red light
is above the green light.
In any event, all a filter can do is to change the relative signal
strength of the receptors from what they would otherwise be. I cannot
understand how such change can end up giving you a richer range of color
compared to what you can see already.
Bill
--
As the years go by, dying just before having to fill out a tax return has merit. |
|
|
| Back to top |
|
|
|
| Salmon Egg... |
| Posted: Sat Nov 07, 2009 7:28 am |
|
|
|
Guest
|
In article
<b9a6d9ca-9114-4ed5-ae0a-6c23c79c8935 at (no spam) k4g2000yqb.googlegroups.com>,
Liz <fraternobombus at (no spam) yahoo.com> wrote:
[quote]Color blindness has been treated by using a red filter in one eye. This
patented process doesn't modify the "color balance" but instead creates a
trick of perception where colors can be distinguished somewhat better.
In this quote note that "color balance" is not defined.[/quote]
"Treatment" is not the right word to use."Modified" or "compensated"
might be a better word to use. As treatment, the method is equivalent to
treating myopia with glasses. Yjr best you can say is that myopia is
compensated. It certainly not cured.
[quote]Fascinating!!! I think this is what birds do (bear with me). They
have drops of colored oil in each cone, which sharply cuts off the
spectrum it can pick up on one side of its curve. This is supposed to
allow the bird to distinguish more colors, or different colors more
easily. It must only work if the brain somehow sorts the input from
each kind of cone...
And whites would look red - definitely not a cure.
I think it would only let you distinguish them because you have two
eyes and are getting different input from each. If you put the same
thing over both eyes, it might not work. If you then integrated the
two images, I'd expect whites to have a pink cast... or whatever you
see as pink.... (sorry, this is really interesting).
It sounds like your glasses are doing whatever they do in some other
different way, perhaps by enhancing some colors and dimming others.
This would produce an artistic effect as well as a practical one.
I'm with your wife - I distinguish colors less well through amber
sunglasses.
You might be able to get clear glasses tinted to many different
colors. A company called BPI makes all kinds of lens dyes that (I
gather) one's optician can order for lenses. Probably expensive.
Aside from my self education my best knowledge of color vision arises[/quote]
from being lucky enough to hear several lectures by Richard Feynman. At
one public lecture with demonstrations, he went into Maxwell's three
color theory. Based on that, color blindness, Land's retinex theory,
colored lights casting shadows with colors not present, and two-strip
Cinecolor or Technicolor are readily explained.
One demonstration showed how what seemed to be projected brown light was
really just yellow light with a different relative illumination compared
to the background. The brain reinterprets color! There is no brown light.
For these and other reasons, Feynman considered COLOR MATCHING to be the
key way to quantify color vision of "normal" and other people. Different
normals tend to be be fairly consistent matching colors while calling
them with different names.
I do not make all my assertions on color on authority alone. On occasion
I have worked on colorimetry (for detectors) and densitometry. All those
fancy formulas in the books I used seem to be self-consistent.
Getting back to the topic at hand, a filter upsets color matching. If
you like that upset, use one or more different filters. In the end, I
cannot understand how any filters can end up changing the color
experience substantially.
Bill
--
As the years go by, dying just before having to fill out a tax return has merit. |
|
|
| Back to top |
|
|
|
| Joe... |
| Posted: Sat Nov 07, 2009 3:01 pm |
|
|
|
Guest
|
On Fri, 06 Nov 2009 21:22:51 -0800, Salmon Egg
<SalmonEgg at (no spam) sbcglobal.net> wrote:
[quote]In article <dqi9f5hjp2hki2v8ahidf19d6fp0k1vv2s at (no spam) 4ax.com>,
Joe <jgandalf1 at (no spam) gmail.com> wrote:
The information I had seen a few years ago may have been pure hype,
but I inferred that it was interference filter layers tailored to an
individual's color shortcomings. Made sense at the time, the trick may
have been the ability to coat lenses on a one-off basis
(economically).
My understanding of color vision is based upon Maxwellian three-color
theory. Although developed over a century ago, this theory has been
augmented but not fundamentally changed over the years.
Normal color vision involves three kinds of cones. Each kind has a
different visual pigment and each kind generates nerve impulses in
proportion (roughly) to how much light gets absorbed by that pigment.
With the three pigments, there are three signals that get sent to the
brain. It is the ratios amongst those signals that the brain interprets
as color,
Because it is impossible for me to know how you perceive a color, most
experiments on color perception are based upon matching of colors. You
might throw in wether a color would have to be redder or bluer to match
a color, only the matching gives an objective result.
In your (Joe) case you only have two kinds of visual pigments. All a
filter can do is to take two colors that appear match to you and distort
the color to where they do not match. It would also be possible to take
colors that do not match and use a filter to make them match. That would
make it possible for you to distinguish traffic signals from one
another, but that can be done in other ways. For example, the red light
is above the green light.
In any event, all a filter can do is to change the relative signal
strength of the receptors from what they would otherwise be. I cannot
understand how such change can end up giving you a richer range of color
compared to what you can see already.
Bill
[/quote]
OK, I am not *completely* color-blind to red - as I mentioned before,
I do see red, just not very well. If the ambient light is brighter, I
see red better, but if the ambient light is dim, red doesn't show up,
so I am left with the impression that the color is black (no color).
"Brighter" reds - more saturation - are easier for me to see than reds
that are darker, muddier, browner, etc. I believe that's why the
filtering out of non-red colors has an effect - less muddying of the
mix makes the red more obvious. So perhaps I have all three pigments,
but the response of the red-sensing one is attenuated for whatever
reason. So when wearing the clip-ons, the other (shorter) wavelengths
are reduced, leaving the red present in proportionally greater
amounts, and producing a more red-emphasized response to my brain.
That's my conception of the solution, anyway. (The clip-ons would be a
good solution, except they are too dark for indoor use - being
sunglasses - and they are cheap Chinese knock-offs, so the lens
material introduces some distortion as well.)
Traffic lights can be a problem. If the sky is very bright, I have a
lot of trouble seeing the red; it just isn't there, so the light
appears to be off (usually the sky isn't so bright as to cause
problems for me, but on a really sunny day...). If I don't see a green
or a yellow light, the logical conclusion is that the light is red.
There is an intersection in an adjacent town that has a light that
only operates when trains come through; if I happen by on a sunny day,
I assume the light is red, and have to take my cues from the general
traffic flow (they oughta just leave it blinking yellow). LED traffic
lights are a little easier for me to see when red.
People like to ask me what color does red look like - well, basically
it looks red, unless conditions aren't favorable for me, then it
doesn't "look" at all - usually it appears black, but with muted
shades of red, the color appears sort of brown. Also, some shades of
purple seem primarily blue.
As an aside, a while back I put a prism in a window, blocked out the
rest of the light and viewed the spectrum. I placed a mark where the
red disappeared, and my wife did the same; her mark was a good
distance from mine - into the "non-color" area. I used the tuning
capability of a spectrophotometer at work to see where my cut-off is.
Of course, it's more of a rapid fall-off, but I could see nothing past
680nm, IIRC.
This post started out as nothing more than a question about the
availability of "selective color-heightening" glasses. I still don't
know if they are available. The added discussion, as usual, has been a
nice side benefit. Is Feynman's color lecture available in print? I
know that Dover has published a lot of his lectures recently. My main
resource has been Nassau's "The Physics And Chemistry Of Color". I
guess I need to get it out and brush up.
I want to thank you and Mike for your input, and if there is more
forthcoming, I will read it (and comment where appropriate) as well.
Joe |
|
|
| Back to top |
|
|
|
| atlieb at (no spam) gmail.com... |
| Posted: Mon Nov 09, 2009 3:13 am |
|
|
|
Guest
|
On Nov 6, 10:02 pm, "Mike Tyner" <mty... at (no spam) mindspring.com> wrote:
[quote]The color tests given by the FAA and the military and the phone company
don't show much improvement with binocular filters.
[/quote]
Which I found fascinating as you can't "fake" not being color blind.
There was one chart that I simply couldn't see the line to trace on
the chart. I passed all other charts with flying colors (pun
intended). I asked about this to the AME and he said if you were
color blind you would see different numbers or trace a different line
then a person not color blind on the very same chart.
Of course don't get me on the binocular test as I fail that miserably
(no stereoscopic vision) |
|
|
| Back to top |
|
|
|
| Salmon Egg... |
| Posted: Mon Nov 09, 2009 11:14 am |
|
|
|
Guest
|
In article
<7ef5bee1-d16a-4bcd-b25d-b209ca42d7ae at (no spam) r3g2000vbi.googlegroups.com>,
"atlieb at (no spam) gmail.com" <atlieb at (no spam) gmail.com> wrote:
[quote]On Nov 6, 10:02 pm, "Mike Tyner" <mty... at (no spam) mindspring.com> wrote:
The color tests given by the FAA and the military and the phone company
don't show much improvement with binocular filters.
Which I found fascinating as you can't "fake" not being color blind.
There was one chart that I simply couldn't see the line to trace on
the chart. I passed all other charts with flying colors (pun
intended). I asked about this to the AME and he said if you were
color blind you would see different numbers or trace a different line
then a person not color blind on the very same chart.
Of course don't get me on the binocular test as I fail that miserably
(no stereoscopic vision)
[/quote]
I do remember, before I lost some of my cone vision, that there were
some Ishihara plates that gave me trouble. With some concentration,
However, I was able to make out the correct color. IIRC, there were some
plates that could make out , with concentration, not only the normal
number but also the abnormal color.
This gets me to the following question. The spectral distribution of
printed plates is going to differ from the spectral distribution on a
computer screen, How significant can those differences be in the
diagnosis of color blindness?
Bill
--
As the years go by, dying just before having to fill out a tax return has merit. |
|
|
| Back to top |
|
|
|
|
|
All times are GMT - 5 Hours
The time now is Sun Nov 29, 2009 9:22 pm
|
|