Why doesn't Iris scanning work on brown eyes?

Never heard it. Why don't you ever cite your sources?

I have!

Guardian Society Supplement

I know but the article or a portion of it would be helpful. I have never heard this but if true, very interesting. I have brown/hazel eyes.

It was saying people with cataracts etc may have difficulty with Iris scanning.

Also on fingerprints, Oriental women may have problems, whether cultural or otherwise, the article didn't explain.

I don't know about brown eye scans in particular, but I did some research on Bioinformation technologies a few years ago for investment purposes and concluded that face recognition was the most likely technology to succeed given the pro's and con's of each method.

I don't know much about that, but wouldn't face recognition be more difficult with twins? I know that twins aren't exactly the same, but could it cause accuracy problems?

I don't remember them addressing the issue of twins when I did the research. But I got the impression that the system was difficult to fool, even with masks and such, but I don't remember the details.

That's really interesting. I'll have to look up more on it.