Patent ID: 6876188

Claim:
An electro-optical voltage sensor for measurement of an electrical voltage V, the voltage V being present between two electrodes arranged spaced apart and generating an electric field E, wherein between the electrodes at least one first electro-optically active layer and at least one second electro-optically active layer are arranged one behind the other along a light path, each of said layers having two axes of birefringence a i,1 , a i,2 , which are respectively assigned a refractive index n i,1 , n i,2 , and, in each of said layers it being possible to alter at least in each case one of said refractive indices, n i,1 , by means of the electric field E, as a result of which a phase and/or a state of polarization of the light can be influenced in each of said layers the index I=1,2 indicating the first and second electro-optically active layer, respectively, an orientation, defined by the axes of birefringence a 1,1 , a 1,2 , of the at least one first electro-optically active layer relative to the light path and the electric field E and an orientation, defined by the axes of birefringence a 2,1 , a 2,2 , of the at least one second electro-optically active layer relative to the light path and the electric field E are chosen in such a way, that the influencing of the phase and/or of the state of polarization of the light in the first layer counteracts the influencing of the phase and/or of the state of polarization of the light in the second layer.