The Zion and Optor are Japanese three-element lenses of the 1930s and 1940s, mounted on camera models by Konishiroku. They were designed at the Konishiroku company, but the majority was manufactured by Asahi Kōgaku.


The Zion was first released in 1932 on the Pearlette, as a 75mm f/6.3 lens. It was also announced in 1933 on the Year-Eight Idea in 10.5cm focal length, with either f/6.3 or f/4.5 maximal aperture. The Zion was substituted in 1933 by the Optor with similar specifications, both on the Pearlette and Idea. It is not known if the lens scheme was modified, or if some other event motivated the name change. The new name was perhaps derived from "Optar", a lens name used by Wollensak, USA. (An interesting turn of events, in a way, since Wollensak at one time briefly made a "Hexar" lens, just like Konishiroku, which was used on Universal's Mercury CC1500 model!)

The Zion and Optor were reportedly designed by Mōri Hirō (毛利広雄) of Rokuoh-sha, the designer of the first Hexar lenses.[1] Their production was outsourced to Asahi Kōgaku (predecessor of Pentax), which also produced the Meniscus Achromat lens of the cheaper Pearlette models.[2] This was presumably because the Rokuoh-sha wanted to concentrate its production line on the more expensive Hexar range and could not mass produce the lenses needed for the Pearlette.

However the Optor lenses of the Baby Pearl and Pearlette are listed as made by Konishiroku in the April 1943 government inquiry on Japanese camera production.[3] This perhaps indicates that the production of the Optor was taken back by the company at some time.

After 1945, Optor lenses were mounted on the Pearlette, Baby Pearl and Semi Pearl until the wartime stocks ran out. The production of the Optor 7.5cm f/4.5 was perhaps briefly resumed, and it seems that a small batch was made with Konishiroku markings (see the corresponding section in the page on the Semi Pearl).


Zion and Optor lenses on civilian cameras[]

Optor lenses on military cameras[]


  1. See this page of the R.Konishi website. Sakai, p.12 of Kurashikku Kamera Senka no.10, also says that the lenses were developed at Rokuoh-sha.
  2. Sakai, p.12 of Kurashikku Kamera Senka no.10, and this page of the R.Konishi website. Shashin to tomo ni hyaku-nen, pp.403–4, only lists the Zion and Optor lens names and says that some lenses were outsourced to Asahi Kōgaku, with no further detail. Lewis, p.182, only says that the Optor lens was made by Asahi.
  3. "Kokusan shashinki no genjōchōsa" ("Inquiry into Japanese cameras"), lens items Jc15 and Ld1.



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