A light source contains at least one light-emitting diode installed in the casing or on the base, and a lens system located along the light flux. The lens system comprises a plane-convex lens, a first plane-concave lens, and a composite lens 4 that are located along the light flux. The composite lens 4 is made up of a second and third plane-concave lenses. Flat surfaces of all of the lenses 4 are outflow faces for the light flux. Axes of symmetry of the second and third plane-concave lenses are normal to each other, whereas axes of symmetry of the first and second plane-concave lenses are parallel to each other. The first plane-concave lens is made movable along the light flux, and has a relocation drive therefor. A solenoid or an electric motor with a gear can be used as the drive. The technical result of the invention is believed to be the improvement of performance indicators, and the structure simplification.