Retinal scanners will probably be defeated in the next 5-10 years.
I thought about this and wondered if you could make a hologram of the inverse of your retina, combined with the retina you want to have, on a contact lens.
That is what I was thinking. A contact lens with the right reflective hologram to look like a retina. Most retina scanners don't have insanely high resolution (usually less than 1 Megapixel)
I thought about this and wondered if you could make a hologram of the inverse of your retina, combined with the retina you want to have, on a contact lens.