Can you expand on this? The cost of material for any coating is always very low, so I assume you are referring to some kind of technological advancement that makes coating easier/cheaper?
"The cost of material for any coating is always very low"
Well...not, historically, for diamond. :-) That's changing.
Not being an expert in this field, I would guess that the barriers would lie primarily in tooling up the process to handle kilometers of material at a go, rather than making one-off surgical cornea scalpels.
Now I'm wondering just how many kilometers of razor blades are produced annually. Many, I'm sure.
