How to secure glass in diopter (M7) ???

[JohnP]

Hello:

Ok, I've just received an empty diopter from Leica, and I've got a new prescription from the optometrist.

This week, it's off to the optician to have him prepare / grind the glass to go into the diopter.

What I can't figure out is how the glass is secured in the diopter... Snap in? Glued in?

Of course, the optician may know, but in the event he doesn't, I thought I'd ask here so that I could pass on the info to the optician.

Thanks,

John

 

[john_s]

Is this the empty device that allows rotation through 90degrees for users with a strong cylindrical correction (Astigmatism)? Is that the reason you need it?

Fixing the lens is the least of the optician's worries. It will be glued, I suppose. Maybe there is not a retaining ring because some users will need lenses of varying thickness, and with uneven edges if they have strong astigmatism.

Just as a matter of interest, what is your prescription?