Microscope in the EEVBlog #168 is an Olympus SZ, 1966 vintage, Greenough design.

[Lawsen]

Dave Jones:
Your stereo zoom is a classic 1966 Olympus SZ greenough optics stereo zoom microscope made in Japan.  It has great depth of field, working distance, 3D, and great eye relief.  It is two microscopes in one to give lower N.A., good eye relief, and working distance to view solder trace quality and circuit boards.  Surf here:

http://www.olympus-global.com/en/corc/history/design/year/1966.cfm

I started in electronics trade, but migrated to geology earth sci about a decade ago.  My mircoscopes are going to be different and larger, Nikon SMZ-U common objective type.  I do not have a Mantis or special ones by Mituyo.  

Lawsen

[EEVblog]

Thanks for the info.
I didn't know it was that old, certainly doesn't look it!
Maybe it's the same design manufactured much later?
The optical quality is indeed very high.

Dave.