The movingcontact is formed by adeepdrawingprocess and at leastonepart (132) has anundulating profilematchingwith that of an adjacentpart of the rotor periphery.
But he also had some unexpected guests: four grim-faced security officials and a uniformed policeman who stayed through part of the interview in an adjacent room.
The harder part will be designing a detector that can distinguish between two adjacent letters on a DNA strand, which are half a nanometer apart, a small fraction of the wavelength of light.