Multi-view Passive Acquisition Device for 3D Face Recognition

The interior of a rheostatic device, such as a throttle-valve position potentiometer having a rotor with sliding spring contact and a housing exposing at least one end of the rotor for operation, is sealed off against environmental effects by at least two hollow cylindrical rotor walls which are located concentrically within each other and extend towards a lid attached to a bottom part of the housing and at least two hollow cylindrical walls of said lid which are concentrically disposed within each other and extend between the rotor walls.