Toronto. One of the very first lenses a young Paul Rudolph designed for Zeiss was its Anastigmat series. The series V is a super wide angle lens offering a 90 degree angle on a full plate (6.5 x 8.5 inches). This is about equal to a 22mm focal length 35mm camera lens.
My lens was made by Bausch and Lomb in Rochester. The most recent patent engraved on it is January 30th, 1891. The aperture covers f/20 to f/256. The name Anastigmat referred to the fact that the design was free of astigmatism along the film plane. The lens was also free of any curvature at the film plane.
Carl Zeiss was a very savvy businessman. The camera lens business took off and he had little factory room for the new endeavour. Worse, countries trying to protect their own nascent optical industries put up high tariff walls. To solve both issues, Zeiss licensed the lens and design technology. Now others in other countries could manufacture Zeiss lenses and sell them far below the cost of imported lenses.
Zeiss tried to trademark the name Anastigmat and failed so he had to change to a new protected name, the Protar. This made Anastigmat badged lenses relatively rare. In the late 1800s there was no common means to describe a lens. Zeiss elected to call the family of lenses a Series with Series V having an angle of view of about 90 degrees. Further, the vignetting-free coverage was determined by specifying the actual coverage of the lens, in this case 6.5 x 8.5 inches or the size of a full glass plate. Other versions of the Series V lens covered more and less than a full plate.
A little over a decade after creating the Anastigmat/Protar series of lenses, Rudolph designed the famous Tessar lens which was improved over the years to be an f/2.8 design. To learn more about Paul Rudolph and the impact of Zeiss, buy the excellent book by the foremost Zeiss authority, Larry Gubas, called Zeiss and Photography (Dec 2015) 890 letter size pages in full colour plus another 400 MB of files on a CD.