View Full Version : Ground Glass Replacement Idea


Luke Brown
December 3rd, 2005, 02:36 PM
Has anyone looked into or tested using corundum instead of glass? Corundum is more commonly know as sapphire and it is formed synthetically for a number of industrial applications from watch crystals to glasses and more.

Here is one supplier of it: http://www.maintechsapphires.com/ Also: http://www.guildoptics.com/applications.html

I used to work in the jewelry industry and can tell you that faceters can get a very uniform frosted look on corundum as compared to other materials. One of the best things about corundum is its strong resistance to chipping and breaking meaning that during the grinding process there is a lower possibility of pitting in the material resulting in grain.

Corundum can be ground extremely flat and also has much greater strength compared to glass. It can also be "grown" in the exact size and shape needed. I'm not sure what its affects would be on chromatic abberation.

DJ Lewis
December 8th, 2005, 04:59 PM
Sounds intresting... have you tried either of these companies? Do you know if these are expensive?

I'm thinking about trying this...

Wayne Kinney
December 8th, 2005, 05:43 PM
this was one material i reseached for SG35. After a few phone calls to some suppliers, i soon found out it was MAJOR expensive.

DJ Lewis
December 8th, 2005, 06:14 PM
oh?! Thanks for the heads up.... did you ever try opal or a holographic diffuser, Wayne?

Wayne Kinney
December 8th, 2005, 06:27 PM
Nope, never went there. Maybe they are a good static solution? Maybe worth a try?

Luke Brown
December 8th, 2005, 08:45 PM
What sort of price were you given? I would imagine that a totally custom solution would be expensive, yes.

However, sapphire crystals on watches were years ago only featured on the higher end models like Rolex's etc. Now you can find them even on watches costing around $150. When I worked as a jeweler the cost for a new synthetic sapphire watch crystal for a generic mens watch was around $55. This was for the big sport watches too that probably had a 30-40mm crystal.

I think part of the problem is that these companies are used to dealing with big corporations and buyers who have massive expense accounts and don't care if one piece costs $1000 because it is for R&D so they price accordingly.