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Colour-blindness is not a major disability, but it can be
awkward in some
situations, such as when defusing a bomb (the red wire
or the green one?)
or.. well, I can't think of any others at the moment.
Howevertheless, MaxCo. has invented a solution for
MaxCo. ColourBack Glasses have an LCD screen,
similar to a regular
LCD display, but containing only the LCD layer and the
colour mask behind it. Thus, it is a programmable filter.
Hence, under suitable control, the glasses can act as a
red-pass filter or a
green-pass filter (or both). Blue is always passed.
When activated, the glasses rapidly switch between red
and green modes.
Each mode is active for a few tenths of a second and,
the durations of the red and green windows differ.
Therefore, a red object will be seen as flickering
between "red/green" and
black; a green object will be seen in the same way, but
with a different
timing. A reddish-green object will flicker in a more
complex way, but less
intensely. The wearer will therefore be able to
distinguish red from green.
(*For clarity: this refers to colour-blind people who
would like to defuse bombs; not bomb-defusers who
want to be colour-blind.)
Notch filter glasses
These claim to significantly reduce the spectral overlap using a notch filter to separate green and red. [scad mientist, Dec 08 2015]
Convert Black and White to colour
someone else talking about this [xenzag, Dec 09 2015]
similar to the idea suggested in my comment [xaviergisz, May 25 2021]
||If the flicker frequency is chosen correctly, these glasses will have the added advantage of inducing epileptic seizures, possibly in those who have never experienced them before.
||Can they be fitted into a Christmas cracker by any chance ?
||Why not just flash the red filter? An object that looks
red/green that isn't flashing is known to be green. An
object that appears to be toggling between red/green
and black is red. Yellow and orange will toggle to darker
shades, but not black.
||So if you avoid the frequencies that can cause epileptic
events, I wonder if flashing slightly faster or slower if the
user's brain would eventually just filter out the flashing
but still recognize the difference between red and green.
According to epilepsy.com, the bad frequency range is
between 5 Hz and 30 Hz. Flashing at 30Hz and above is
generally considered to be largely invisible to humans. Is
that a physical limit to the photo sensors, or is it that our
brains filter out that flickering? Is red or green vision
more sensitive to flickering? Maybe individuals would
learn to sense flickering faster than 30 Hz and have their
brain simply interpret it as green or red.
||While checking to see how colorblindness worked (to make
sure my question about the possibility of red or green
vision being more sensitive to flickering) I ran across an
interesting link to Enchroma that sounds like a fairly good
solution for many people, but not those with 100% red-
green color blindness . No batteries required. see <link>
||[Max]'s solution should work for someone with 100% red-
green color blindness, so [+]. Even though it does need
batteries (or a solar cell).
||I like the notch-filter glasses (which, as far as I can
tell, help by filtering out the part of the spectrum
where red and green get confused in most colour-
||Thinking about it, the slow flicker I suggested
would probably be incredibly distracting. It might
be better to flicker each colour at a fairly high
rate, close to the persistence time. Also, I guess
only one colour (red, or green) would need to
||So, maybe just red-filtering glasses whose flicker
rate was 25Hz. That way, most things would look
"normal", except that red objects would have a
just-perceptible flicker. The redder the object,
the greater the flicker, but even a solid-red object
would look "OK", just like a low-frame-rate movie.
||These are LCD screens, so what is seen is a representation, right? Could one not substitute one color for another?
||Yes, Predator 2. The coolest thing was when El Predator clicked his goggles thru various spectra until he could see the folks in the infrared cloak suits. The LCD screens on Maxs goggles should click thru various color substitutions until there is one which suitably distinguishes the various wires.
||//These are LCD screens, so what is seen is a
representation, right? Could one not substitute one
color for another?//
||No - I didn't explain as well as I could have. They
*are* LCD screens, but only the LCD layer (and the
pixel-mask behind it) - nothing else. So they act as
||I've thought of a hybrid solution between this idea and the enChroma glasses (in scad mientist link).
||Make a pair of glasses with one lens clear and the other having a green notch filter (band-stop filter). Red light will go through both lenses, whereas green light would only go through only one lens. Thus to a colourblind person red would look normal, but green would appear as a weird stereoscopic effect.
||Optical notch filters can be easily made with multiple layers of thin film or using a single layer of cholesteric liquid crystal.
||//Red light will go through both lenses, whereas
green light would only go through only one lens//
That would work! I think the brain would "null out"
the effect over time, but the wearer could simply
wink one eye and see if the object got suddenly
||On pondering this idea I realized that standard old school green/ red folkdout paper 3d glasses should work; I see essentially the same thing now in the annos. I know a tractable colorblind gentleman whom I will ask to test the idea.
||There is something about this that reminds me of the amazing device which was once on sale, that converted black and white TVs into full colour TVs. The amazing device was a sheet of sticky-backed plastic with a blue fading to green tint on it. (see link if I can find) I bet it was Max who was behind it all along.
||That sounds much more like one of Sturton's dubious money-making schemes. M'Lord B. woud not besmirch a single one of his dozen fingers by deigning to involve himself in mere commerce.
||Sturton, however, is an entirely different coalscuttle of monotremes, being forever in need of ready money to finance his "expeditions", cover the costs of the resultant vital medical treatment, pay for the environmental cleanup, but mostly for bail.
||This is more or less what I was thinking of for a classmate of
mine who is colorblind and was disappointed when told he'd
never be able to make Ethernet cables. I was thinking of
manually switched plastic filters, though.
||But the anaglyph glasses (old-school 3D glasses) could work too!
I'll try to get him to try those.
||And was EnChroma the thing that was announced with much
fanfare a couple of months ago? We heard about that but didn't
actually look into it. It looks really cool.
||//Sturton, however, is an entirely different
coalscuttle of monotremes//
||Indeed he is. His third volume of court transcripts
(illustrated with excerpts from the witnesses for the
prosecution) is due out shortly, just in time for
Christmas. In view of the season, he's added a bonus
chapter featuring the reindeer case (Uppsala Wildlife
Management vs. Buchanan (b)).