Lighting light module having light beam scanning, notably for motor vehicles, comprising a light source configured for generating a light beam which has a slow axis and a fast axis, a wavelength conversion element having a conversion surface, and scanning means arranged for scanning the conversion surface with the light beam, the light module comprising moreover a focussing system arranged for focussing the light beam onto the conversion element and for adapting the width of the light beam to the dimensions of the scanning means, the focussing system comprising a lens convergent along the fast and slow axes, the lens being provided with an input dioptre and an output dioptre of the light beam, the input dioptre being substantially cylindrical in such a way as to make the light beam converge only along the fast axis until inducing a point of inversion of the image of the light source inside the lens before the beam reaches the output dioptre.