The invention relates to a roll screen having variable screening apertures having axle-fitted rolls which are spaced at adjustable distances apart and a device for adjusting this spacing. The roll spacing adjusting device functions to act on all rolls simultaneously, so that the spacing change will be the same for all rolls. The device includes two parallel running tracks (10, 11) and the distance between these tracks can be varied. A change in the distance between the running tracks causes the roll axle housings (6) to rotate and move the axles (2). This roll screen also includes a device for adjusting the individual distance between two consecutive rolls without affecting the distances between the remaining rolls. This device includes a spacer (32) which is inserted between the housings of the two rolls in which the roll axles are journalled. The roll screen is also provided with a separate elastic sealing element between the roll axle and the roll drive arrangement.