PROBLEM TO BE SOLVED: To perform parallel eccentricity adjustment of an optical element with the amount of optical axis tilt being suppressed within a tolerance limit.SOLUTION: An eccentricity adjustor includes three eccentric rollers each of which is positioned at the intersection of a guide groove 14a and a cam groove 16a. Each eccentric roller includes a first cylindrical part 41 inserted into the cam groove, a second cylindrical part 42 that is inserted into the guide groove and is concentric with the first cylindrical part, and a third cylindrical part 43 that is eccentric to the first and the second cylindrical parts and is engaged by a third lens-barrel 6. The three eccentric rollers are composed of two eccentric rollers 40 and one eccentric roller 50. The first eccentricity of the third cylindrical part of the eccentric roller is larger than the second eccentricity of the third cylindrical part of the second eccentric roller.
