Abstract: Techniques and assemblies for steering light rays are described. An electro-optic prism is operable to provide controllable steering of solar rays. The electro-optic prism includes a first electrode, a reference electrode and an electro-optic material positioned between the first and reference electrodes. In one implementation, the first electrode includes multiple substantially parallel linear electrodes positioned on a first substrate and the reference electrode is positioned on a second substrate. Such implementation can include that when separately controllable voltages are provided to at least some of the linear electrodes, a gradient electric field is provided within the electro-optic material to cause the electro-optic material to have a refractive index gradient. The refractive index gradient can be controlled by varying the magnitude of the separately controllable voltages provided to at least some of the linear electrodes.