Nikkor Serial Numbers, Replicating.

[RonVol]

A small coincidence picked up by a friend of mine.
Two very early Nikkors with the same serial numbers.

Aero-Nikkor 20cm f:3.5, #3831716
Tele-Nikkor 40cm f:5.6, #3831716

[Macro_Cosmos]

Two very weird lenses o.O

Would love to know its application. I assume it has something to do with aerial imaging/targeting on fighter jets and the such, hence the designation of "Aero"?

Interesting!

[RonVol]

Two very weird lenses o.O

Would love to know its application. I assume it has something to do with aerial imaging/targeting on fighter jets and the such, hence the designation of "Aero"?

Interesting!

In 1917, the optics department of Tokyo Keiki's factory, the Iwaki Glass Factory, and the Fuji Lens Factory combined to found “Nippon Kogaku K.K.” and began manufacturing binoculars for consumer use. Then, in 1932“NIKKOR”, a combination of “NIKKO”, the abbreviation of “Nippon Kogaku”, and an“R”added at the end, appeared as the trademark of a line of photography lenses. The true history the NIKKOR lenses begins, however, with the “Aero-NIKKOR”, an aerial photography lens used for mapmaking that was supplied to the military. An extremely precise lens is essential for creating accurate and detailed maps. In order to meet this demand, the first lenses were all crafted by hand. The result was the release of the Aero-NIKKOR 18cm f/4.5(1933), the 7.5cm f/3.5(1937), and the 10cm f/5.6(1939). From this historic start, NIKKOR proceeded to expand to consumer and industrial use, and eventually grew into Japan's most iconic brand of high power lenses.

http://www.nikkor.com/history/

[Roland Vink]

Many early Nikkors used the date as part of the serial number. For example the 38xxxxx might indicate the year 1938, which suggests both were made in the same year.

[Akira]

The Aero-Nikkor 50cm f5.6 shown in Mr. Akiyama's "Red Book Nikkor" website also carries the serial number starting with "38" but having eight digits (38352376):

http://redbook-jp.com/redbook/vin/a01.html

According to the accompanying description, the lens was made in 1944, so, apparently 38 doesn't indicate the year of its production.

I thought a two-digit number in the serial number might indicate the year in the Japanese era name "Showa".  But 1944 falls on the 19th year of Showa.  Considering that no "19" appears in the serial number on the 50cm f5.6 Aero-Nikkor linked above, it is not likely that it contains the year of production.

I also thought about the possibility of using another era name used until the end of the WWII which is "Kohki", counted from the birth of the legendary first emperor called "Jin-mu".  We celebrated the 2600th year of Kohki in 1940, and thus 1944 falls on the 2604th year of Kohki.  Again, there is no number suggesting this era name.

Ron, do you know when these Nikkors (Aero-Nikkor 20cm f3.5 and Tele-Nikkor 40cm f5.6) were designed?  The year of design might be indicated in the serial number.

[RonVol]

Ron, do you know when these Nikkors (Aero-Nikkor 20cm f3.5 and Tele-Nikkor 40cm f5.6) were designed?  The year of design might be indicated in the serial number.

Thanks for trying to figure out the meaning of the numbers.

Unfortunately I know very little about the Aero-Nikkors.
The Tele-Nikkor is a type of lens that I've only just found out about, the image above is the first I've seen this lens.

I would imagine that the best person to ask about these lenses would be Mr. Akiyama.