A light-collimating system for collimating light from a light source has a plurality of elements (2, 2′, . . . ), each element including at least a first wall (3, 3′, . . . ) and at least a second wall (4, 4′, . . . ). The first (3) and second wall (4′) of adjacent elements are spaced with respect to each other at a side of the light-collimating system facing the light source, the spacing defining an aperture window (5, 5′, . . . ) for admitting light into the light-collimating system. The first and second wall of said adjacent elements form a wedge-shaped structure widening in a direction facing away from the light source. The first and the second wall are provided with a specular reflecting surface at a side facing the wedge-shaped structure. According to the invention, the wedge angle (w of the first and second wall with respect to the normal on the aperture window are adjustable for enabling adjustable collimation.