Vehicle assembly comprising a radar sensor and an arrangement of layers

A vehicle assembly for a vehicle, the vehicle assembly comprising:

• a radar configured to transmit radar waves in a range of wavelengths;
• and
• an arrangement of layers placed facing the radar sensor and configured to perform a luminous function, the arrangement of layers including a first sub-assembly of at least one layer that is reflective in the visible domain, each layer having a primary refractive index and a primary thickness, and a second sub-assembly of at least one layer that is transparent in the visible domain, each layer having a secondary refractive index, with the primary refractive index being high with respect to the secondary refractive index in the radar domain,
• and the total thickness of the first sub-assembly of layers is dimensioned so that there is a phase shift of π modulo 2π between the waves of the radar waves incident on the outer face of the first sub-assembly and the waves reflected by the interface between the first sub-assembly and the second sub-assembly as they exit the first sub-assembly.