An objective lens system (2), particularly for a fingerprint reader apparatus, said lens system (2) comprising a first lens (8) formed as a condensing lens guiding light beams arriving from an object generally telecentrically, an aperture stop (9) having a centre (P) and being located in the vicinity of a focal point of the first lens (8), a correcting second lens (10) arranged between the first lens (8) and the aperture stop (9) and juxtaposed with the aperture stop (9), and a correcting third lens (11) formed as a condensing lens and arranged beside the aperture stop (9) opposite the second lens (10). According to the invention, the second lens (10) is a condensing lens with a spherical surface (S₃) facing the first lens (8), wherein the curvature centre of the surface (S₃) is at a distance shorter than 15% of the curvature radius of the surface (S₃) from the centre (P) of the aperture stop (9), and the aperture stop (9) is arranged at a distance shorter than 25% of the focal length of the first lens (8) from the focal point of the first lens (8).