light path switching member housed within the housing an actuator member disposed in the housing for transferring an external mechanical force to the light path switching member a light entrance member disposed on the housing connectable to a first optical fiber for guiding light transferred from an external light source through the first optical fiber to the light path switching member and a light exit member disposed on the housing connectable to a second optical fiber for guiding light from the light path switching member to the second optical fiber the light path switching member being associated with the actuator member so as to switch a light path from the light entrance member to the light exit member through the light path switching member application_number US 53409983 A description referring now to fig1 there is shown a remote control system in which non contact switching devices a 1 to a n are employed as a preferred embodiment of this invention each of the non contact switching devices a 1 to a n includes a sensing unit 1 having a actuator 2 a signal processor 3 for producing a switching signal cooperating with the unit 1 and light projecting and receiving optical fibers 4 and 5 connected between the unit 1 and the processor 3 the respective devices a 1 to a n are connected through data bus 7 to a controller 6 e g programmable controller which controls or processes signals from or to the respective devices a 1 to a n the sensing unit 1 is illustrated in fig2 and 4 the unit 1 includes a housing 11.