Lenses for Custom Sunglasses - OptiBoard Discussion Forums

I'm in the prototyping stage for a small run of sunglasses I've designed. I've been speaking with a company in China who can provide ridiculously cheap blanks, both in plastic (CR-39, poly, hi-index) and glass. They assure me they can cut the lenses but they never give me a response when I offer the actual frames or CAD files for their lab to get a quote. The language barrier is a bit difficult and I've been speaking to them for about a month now with still very little headway.

I'm wondering if anyone here knows a lab here in the States or Canada that can cut plano blanks (2-3mm thick) without charging retail price. I had samples done by a lab in polycarbonate which cost $100.

Another big question is to do glass or plastic. I would prefer glass as I will be charging quite a bit for the product and want the best optics possible. Polycarbonate has awful optics as far as I'm concerned and they scratch easily. On the flip side, those are glass's two biggest strengths. Weight will not be a factor but I recognize the risk of glass shattering.

Is tempered borosilicate nowadays any stronger than the past? If the lens shatters into uniform pieces and not shards, shouldn't that protect the eye? Personally, I wear my gradient Rx sunglasses all day and night and have so far never had a problem with things flying at my face.

I have heard that few, if any, companies presently have the machines to apply mirror coating to glass. If this is the case then I must use plastic.

I'd prefer to use Hi-Index, unless anyone knows of a plastic with better optics.
Does anyone have any experience with Kaenon's SR-91? It's supposed to be pretty revolutionary.

Many thanks. They'd have to be bare-bones-basement-bottom priced to compete today. The market is literally awash in cheap sun product. I would think the next sun breakthrough would as likely be made on the other end of the spectrum: Extremely high quality. Nothing but glass. Polar options using the finest filter medium you can possibly source. Dielectric mirror options. Everything backside A/R. Super tough scratch resistance, and back it all up with a quality guarantee.

Take the very best of what Rēvo, Serengeti, Maui, RayBan, Vuarnet, etc. were two decades ago. Find a way to do even better today.