PURPOSE: To eliminate the need for the positional adjustment of a wiper for a lens by wiping a lens face by a wiper having at least the same length as the outer diameter of the lens.

CONSTITUTION: A wiper 12 is formed in a hourglass shape whose both end parts in the longitudinal direction are made in a large diameter and whose center part in a small diameter, in case of a lens 10 being a convex lens. This wiper 12 is simultaneously rotated centering around rotating center shafts A, B, while its abutting on the lens 10 whole face. Wiping can thus be performed without changing the wiper 12 for the lens 10 same as the length of the wiper 12 and small, a relative speed can be generated on all of the abutment faces on the lens 10 as well and the cleaning effect is improved.