På 20. feb. 2004 kl. 19.02 skrev Andre Langevin:
The glass of a lens should be about the same Moh's hardness as quartz, 7,
since it's predominately quartz. I have no idea about the hardness of
coatings, but aren't they only a few molecules thick?
Bill
Pentax says its SMC coating is harder than glass. Very hard molecules...
I think it IS glass, but glass being doped with impurities to increase the refractive index. The refractive index is related to the hardness of the glass.
DagT