Abstract: An optical switch comprising a base (1) having a light path (4, 5) passing therethrough, a guide slot (6) intersecting said path, a moving shutter (24) displaceable at least partially inside said guide slot (6) between a position where it allows light to pass along said path and a position where it interrupts said passage, and a return spring (22) for the shutter, the switch being characterized in that said shutter (24) and said spring (22) constitute portions of a deformable blade (2), the spring (22) being fixed at one of its ends to the base, and the moving portion of said blade having a surface (21) which is large enough to be capable of responding to magnetic attraction exerted against the action of said spring.