| http://www.w3.org/ns/prov#value | - This is attained in that the light switch comprises an optical means, e.g. a lens, for focusing incident light, said optical means being displacable along a plane coinciding with a plane extending through the center axes of the optical-fiber light conductors, transversely of the light path from the optical system, to a number of positions corresponding at least to the number of end portions of opt
|
