Newsmaker: Bringing color to the color-blind

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Can you briefly explain the technology behind your ColorPath color night vision goggles?
Jones: The expensive core of a night vision device is the image intensifier tube. It takes the light from the front end and magnifies it 10,000 times and then projects it on a green screen at the back. We have two very specific, very difficult-to-make filters, one in the front and one in behind the tube. But there are two channels and that's our innovation. Each filter has two channels and it alternately puts one channel in front of the tube. So we're on the simple end mechanically of the technology spectrum. The composition of the filters is what took us a couple of years to get control of and figure out how to leverage.

Because the colors that you "see" aren't actually hitting your eye. It goes back to that theory that Land had about how your brain looks at the data it's getting from your eyes and figures out how to paint the colors that you see in your brain. We came up with a way to give your brain these two channels of information, to fill in the colors.

Your eyes actually are actually are pretty crappy if you think about. It's a single lens made out of biological material and optical nerves that aren't very big.

None of those colors, or few of those colors, are actually hitting your eye, but your brain is making the scene look correct for you. The Retinex theory gave us the framework to think about how to do that. The practical advantage is that U.S. military owns tens of thousands of image intensifier tubes, the expensive part, and they don't need to get new ones. They can use an existing tube in our housing.

What does this mean for medics and military working in the field at night? What can they do now that was impossible before?
Jones: Well, let's take the medic case first. Under green night vision, blood looks the same color as water. So if you trying to set an IV with the regular green night vision you can't tell, because the fluid looks the same color as the blood. (Editors' note: Jones explained that medics need to see a little blood to know if they've hit a vein.) Obviously in combat we tend to fight at night using night vision because the bad guys by and large don't have night vision. You don't want to turn on the light if you're treating someone because that makes you a target.

There are other things where color at night is useful. Imagine you're looking for a kid who's lost in the woods and has a red sweater.

One of the guys we were showing prototypes to worked after (Hurricane) Katrina. He said you're going into a place, you've lost power, everything is ripped apart and you're looking at something trying to figure if it's an electric line or a water hose that you're about to step on.

We've been working with various military and Special Forces contacts to get their feedback. Our first production we expect to have in the market sometime this summer. And then we start the whole process of selling it into the Army, which we have done with other innovative technologies, which has surprisingly a (long, drawn-out process).

Is this only going to be sold to the military, or could medics working in civilian life be able to purchase these?
Jones: Our first concentration is on the military medic market.

Depth of field is another problem with night vision goggles. Does ColorPath deal with that issue?
Jones: It helps because your brain uses color for what's called scene segmentation. Your eyes actually are pretty crappy if you think about. It's a single lens made out of biological material and optical nerves that aren't very big. But you have a very expensive computer inside your head that takes these lousy images and does all sorts of enhancements. Your brain is using color at that first glance to help you make sense of what you're seeing in front of you.

Your brain uses color at a very primitive level for recognition. For instance, if you're looking with regular night vision out across a golf course, you have to sit there and try to figure out what's grass, what's the sand trap, what's the water hazard. With color you go, "Oh, grass, sand, water, and then there's some more grass on the other side," because the colors are giving you the answers instantly and you don't have to make sense of the different gray-scale values. So it isn't depth perception per se, but you're orienting yourself very quickly, so it does help a lot in terms of how quickly I make sense.

What is the battery usage?
Jones: You can get overnight with a pair of AA (batteries), which is the usual military goal.

I'm assuming this works in real time?
Jones: Yes, and that's another issue because there are other ways you could think about doing color, but now it has a quarter-second delay and that's not a good thing.

Can you explain the difference between the medic and the military ops version?
Jones: We can give you color down to a thin crescent moon, but below that our technology is taking too much energy out of the system for you to see well. We can move the filters out of the way (with the combat one). You just turn the knob, the filters go out of the way, you're back with what you started with (green night vision), but that isn't necessary for the medic. 

More Newsmakers

[NoVista]

Virtual colour

At one time, he was listed in the Guinness Book of World Records as the world's richest scientist. [borrowed from Wikipedia]

There's a good biography by McElheny, "Insisting on the Impossible".

When I was a budding television engineer, somebody told me about Land's two-colour experiments. That was published first, I believe in Scientific American, 1959 ...

Around the late 60s, the Japanese did some colour rendering experiments using black-and-white film projectors, and probably some exectronic switching, taking advantage of human persistence of vision.

I remembered from uni psychology class, some rotating disk with a pattern on it which at some rpm speed produced a colour effect. Aha, so I did an experiment in the workshop once with a B&W camera, greyscale chart, and experimental field switching breadboard. Although I didn't achieve a broad spectrum, there was some virtual colour perception. For me, and others. Curiously, one or two witnesses still saw nothing but B&W.