An electro-optical assembly, in particular a sensor assembly for detecting ambient light, includes a reflection surface, a lens body and an electro-optical component, in particular a light receiver. The component includes a depression having a main lens section, in particular a diverging lens section with a concave interior wall, and a converging lens section with a convex interior wall. The interior wall of the converging lens section is formed in such a way that the rays of the ray path which travel through the converging lens section to the electro-optical component hit the reflection surface in such way that the angle of incidence at the reflection surface is larger or the same as the critical angle of the total internal reflection at the reflection surface. In another aspect a method for detecting ambient light is described.