In article ,
raden writes:

In Watford , who make spectacle lenses, Olds Approach, ?

When I used to work down the road in Elstree, Carl Zeiss
had a factory just nearby which I believe made spectacle
lenses. They specialised in using very high refractive
index glass to make what would otherwise be high prescription
heavy lenses somewhat lighter. I would imagine they would
not be at the cheaper end of the market though.

--
Andrew Gabriel