Glass or plastic? If plastic, there is no problem. You can use a regular
twist drill. Start with a small drill about 1/8 and work up.
Glass is going to be a problem as glass lenses are tempered. If you require
a glass lens then you are probably going to have to get a lens blank from an
optician and drill it while the glass is soft.
Now why in the heck are you drilling a hole in a lens?
About the time I had mastered getting the toothpaste back in the tube, then
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