Would an iris scan work if you were unconscious or your eyeball was detached?
I spy with my little eye, it can be possible to trick biometric security measures with a photo or gain access from an unwilling pass holder.
In a word, yes. Iris recognition is different from retinal scanning in that it measures only the surface appearance of the eye. An iris scanner is just a high-resolution digital camera coupled to some sophisticated image-processing software that distinguishes the coloured part of the eye from eyelids, eyelashes and pupil, and compensates for environmental factors.
Iris recognition has a much better match rate than fingerprint scanning and is less intrusive than retinal scanning but, like most other biometric scanning methods, it has trouble with live tissue recognition. An iris scan will match against your eye, whether you are conscious or unconscious, live or dead. Worse still, it can even be fooled by a high-quality photo. There are ways around this but, at the moment, iris recognition is not suitable for unattended scanning.
Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.