Trustworthy optomechanical switch

摘要

A switch having two apertured plates one of which is movable relative to the other to occupy spaced switch positions, the apertures being arranged in the plates so that in each switch position two or more pairs of apertures are aligned and all others are masked, wherein light transmitted through a selected one of the two or more aligned aperture pairs in a particular switch position is visible through an external switch position indicating window to thereby provide an unambiguous indication that the movable plate is positively registered in the particular switch position.