[AgX]

According to Pentax history, Pentax came from Pentacon and Contax...

-) Contax itself is derived from Contessa-Nagel Company

-) Pentacon itself was derived from Pentaprism and Contax, due to legal issues as result of the division of Germany and the splitting of companies (the original manufacturer of the Contax added with many other manufacturers formed the new company Pentacon)

-) Pentax seemingly was established similarly, as stated above.

-) Pentax was a trade name of 8mm cine projectors made by Pentacon

-) after the retraction from the manufacture of these projectors the tradename Pentax was sold to Asahi Kōgaku Kōgyō K.K. (or its successor).