process.

He applied to the imperial patent office in Berlin for a patent covering an "electric telescope" for the "electric reproduction of illuminating objects", in the category "electric apparatuses". This was granted on 15 January 1885, retroactive to 6 January 1884. It is not known whether Nipkow ever attempted a practical realization of this disk, but one may assume that he himself never constructed one. The patent lapsed after 15 years owing to lack of interest. Nipkow took up a position as a construction