Optical switch

An optical switch provided with a light input side and a light output side, the switch comprising:

• on one of its sides, a plurality of optical waveguides having collimating lenses, one lens at one end of each of said plurality of waveguides, the plurality of lenses being located in spaced-apart predetermined positions around at least one pitch circle and mounted upon a faceplate;
• on the other of its sides, an optical waveguide having a movable light collimating lens at one end;
• means for moving said movable lens and the end of its waveguide selectively from one switching position to another in each of which light is transferable between it and any one of the plurality of lenses, said moving means comprising an electric stepping motor and a control means sensitive to the reception of input signals to rotate the stepping motor a required angular distance to locate the movable lens in a desired switching position, the motor having a rotatable shaft and the movable lens mounted upon an arm secured to and extending radially from the rotatable shaft;
• and
• means to prevent light from passing between the movable lens and any of the plurality of lenses as the movable lens travels to a selected switching position, said light preventing means comprising a further electric motor and a rack and pinion, the arm being radially slidable upon the shaft of the stepping motor with the rack secured to the arm and the pinion in mesh with the rack and drivable by the further electric motor, to move the arm and thus the movable lens away from the arc of the circle as the stepping motor is activated and onto the arc upon assuming a selected switching position.