harv@harvs.UUCP (Patrick L. Harvey) (06/11/91)
I am looking for information about color blindness. I am slightly red-green color blind, meaning that I can confuse certain shades of red and green. I assume that the problem is that my eyes cannot differentiate between frequencies as accurately as they should be able to, because if I see certain colors reflected off glass (not a mirror - a crude reflector, like a car window at night) the colors are more distinct. I am guessing that this is a result of spectral spreading (prism effect), but I really have no idea. I surmise this is the case because I used to have an obnoxious power amp in my car, and when viewing the front panel LEDs directly they all looked the same. But at night, looking at their reflection in the window glass, they were very obviously red, green, or yellow. Also, if they were illuminated by external lights (rather than glowing themselves) the colors were obvious. Does vision acuity affect color vision? Say, if I have 20/40 vision, will my color vision be better if I wear glasses to correct it to 20/20 or 20/15? (I do not wear glasses - have about 20/25 or something). Are there drugs which affect color vision? Do certain vitamins or minerals affect the way eyes interpret colors? (other than hallucinogens) Why do colors appear to be substantially more vibrant under water when using a mask? (there is a 5:4 magnification factor when using a plain diving mask) Please mail me responses directly and/or post, as my news server has been quite erratic lately. I will compile and post answers. Thanks very much! ----------------------------------------------------------------------- Patrick L. Harvey | Home: romed!harvs!harv@asuvax.eas.asu.edu VLSI Technology, Inc. | Work: vlsisj!phx!harv@decwrl.dec.com (602) 752-6151 | Other: Sorry, no Email in the Grand Canyon
sarima@tdatirv.UUCP (Stanley Friesen) (06/15/91)
In article <0B02FFF5.htcdri@harvs.UUCP> romed!harvs!harv@asuvax.eas.asu.edu writes: >I am looking for information about color blindness. I am slightly red-green >color blind, meaning that I can confuse certain shades of red and green. > >I assume that the problem is that my eyes cannot differentiate between >frequencies as accurately as they should be able to, because if I see certain >colors reflected off glass (not a mirror - a crude reflector, like a car window >at night) the colors are more distinct. Good enough as far as it goes. The eye has three types of color sensitive receptors (conventionally called Red, Green and Blue - but that is an oversimplification). These are wired into the optic nerve in an arcane way that recodes the light levels into two color opposition systems. These two are a Red-Green opposition and a Yellow-Blue opposition. Red- green color blindness is caused by some defect in the Red-Green opposition system. That is the R-G encoding has reduced contrast - or even no contrast at all (in severe cases). [There is also a third opposition - between light and dark]. This can be caused by several things - one of the receptor types could be missing, leading to reduced signal differentiation; or the peak sensitivities of the red and green receptors could be offset towards each other; or ... As to why reflection helps, I do not know. >Does vision acuity affect color vision? Say, if I have 20/40 vision, will >my color vision be better if I wear glasses to correct it to 20/20 or 20/15? >(I do not wear glasses - have about 20/25 or something). I doubt it, but I do not know for certain. >Are there drugs which affect color vision? Do certain vitamins or minerals >affect the way eyes interpret colors? (other than hallucinogens) Quite likely, and probably. Anything that alters the metabolism of the receptors or neurons could alter color vision under the right conditions. -- --------------- uunet!tdatirv!sarima (Stanley Friesen)