The disclosure relates to a device and method for testing a concentrated photovoltaic module comprising a plurality of sub-modules, which comprises: light sources; and parabolic mirrors coupled with the light sources so as to reflect the light from each source in quasi-collimated light beams toward the module to be tested, perpendicular to the module. Each light source comprises: an optical system comprising two parallel lenses on either side of a diaphragm; a lamp on an optical axis of the optical system; a reflector arranged on the axis, on the side opposite the optical system relative to the lamp, and translatably movable along the axis; and a housing containing the optical system, the lamp and the reflector and including an outlet opening for the light beam on the axis.