I remember the ColorMax lenses from about 15 years ago - they relied on multiple coatings to filter out certain parts of the spectrum, thus allowing color deficient patients to discriminate between certain colors. The 2 patients I had wearing them were very disappointed - they had all kinds of strange reflections that were annoying. I'll do a "wait 'n see" on this one.
Lost and confused in an optical wonderland!
My last article in L&T magazine was a primer on this entire topic:
http://www.2020mag.com/l-and-t/55017/
http://enchroma.com/product-category...ndness-glasses /
For the last few days :
This webpage has a redirect loop
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Seems to me that you'd have to measure the patient's particular color sensitivity before designing the lenses to selectively attenuate the normally perceived wavelengths.
Do they do that?
This is from the tech page of the site. They're not claiming a cure.Originally Posted by drk
The general class of filters that are designed by our method are called multi-notch filters: they contain one or more sharp “cutouts” in the visible spectrum. To make a lens that helps with red-green color blindness, the notch filtering occurs primarily in the spectral region corresponding to the maximum overlap between the red and green photopigments. Effectively, this drives a kind of wedge between the L-cone and M-cone signals, thus improving the separation of their signals and providing better color vision to the deficient observer. We don’t claim that this is a cure for color blindness — it is not a cure. Like any eyeglass product, it is an optical assistive device.
Very astute, drk. Ian Jordan does exactly that!
Who B Ian Jordan?
He's a very busy man of late. I've heard his trip to the states fell through but he is working on some on line videos.
Search the name for some other threads on Optiboard that he's chimed in on.
They are basically a good idea - BUT - they are not a panacea and are essentially a way of making colour vision different - but it will give the impression of "curing" the problem. We can get someone through the Ishihara easily enough in most cases (again this does not make a colour defective become cured) but it can achieve significant improvements. We place Ishihara on lectern and modify LMS ratios using additive colour instrument. In most cases there is a colour space position in which the Ishihara becomes completely readable and it appears that colour vision is normal. We then work out the mathematics to enable this absolute colour position to be converted to a lens for a given environment - or if possible - all normal ambient lighting. The lens allows the Ishihara to be seen normally
The master speaks!
Good stuff!
B
Ishihara? Those are screening plates. Can't you modify your technique and at least use a D-15 test?
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