The Zeiss Protar

Original Zeiss documentation - Some sets - German patents - US patents - Stops tables

Original Zeiss documentation (1901)


Some examples of protar set.


The german patent

Protar (asymetric doublets)
Carl Zeiss, Optische Werkstaette Jena: Deutsche Patentschrift 56109
v. 3 April 1890, granted 20. Mai 1891.

The real inventor is Dr. P. Rudolph (1889)

A patent for the serie VI was granted in 1893.

To be able to follow the demand they were produced under a Zeiss License 
in the US, UK, France (Krauss) and Italy (Koristka).

Double Protar Serie VII (anastigmat) Dr. P. Rudolph (1894). 

The first double protar are available on the market in Q2 1895.

Dr. P. Rudolph: English patent v.17. Nov. 1894 No. 19509.
British journal of Photography 1894, 28 VII. pag. 829.

The United States patent 532,398 dated January 8, 1895.

Please refer to the U.S. patent and Trade-Mark Office site at "http://www.uspto.gov".

The United States patent 1,021,337 dated March 26, 1912.


Aperture table

This table is the table I use, taken from the above documentation.
Serie,NumberFront-Backgiven freal f453222.6181612.511.387.2
 Protar 1:181801693.55.57.59.5     
VII,835-291791603.557 10 142022
VII,941-291921713.55.57.5 11 1521 
VII,1141-35216191468.5 12 172427
VII,1248-352322044.56.59 13 1825 
VII,1448-412542225710 14 202831
VII,3-292852916.5913 1823   
VII,4-3535035481116 2228   
VII,5-4141241391318 2628   
VII,6-48480482111521 3033   

The table as a text file: mytable.txt
A summary of Protar lenses as a text file: ic.txt