An oscillatory actuator comprising: a case made of a non-magnetic material; an electromagnetic driver in a tubular shape inside the case ; a mover disposed radially inside the electromagnetic driver and oscillatably supported along an oscillation axis; and a pair of leaf springs each configured to support either oscillation-axial end of the mover , the mover including a magnet , a pair of pole pieces being made of a soft magnetic material and sandwiching the magnet from either side in the oscillation axis, and a pair of weights being made of a non-magnetic material and sandwiching the pair of pole pieces from either side in the oscillation axis, the electromagnetic driver including a pair of coils , each in a cylindrical shape, spaced apart from each other along the oscillation axis, and a yoke in a tubular shape disposed radially outside the pair of coils , the yoke being made of a soft magnetic material and projecting outward beyond the pair of coils along the oscillation axis, and the yoke having one or more cutouts along each edge in the direction of the oscillation axis; and characterized in that : along the oscillation axis, the yoke has an average length greater than or equal to a sum of an end-to-end length of the pair of pole pieces and the double of a one-way amplitude of oscillation of the mover , and along the oscillation axis, the yoke has a minimum length greater than or equal to a sum of an end-to-end length of the pair of pole pieces and the double of a one-way amplitude of oscillation of the mover . a case made of a non-magnetic material; an electromagnetic driver in a tubular shape inside the case ; a mover disposed radially inside the electromagnetic driver and oscillatably supported along an oscillation axis; and a pair of leaf springs each configured to support either oscillation-axial end of the mover , the mover including a magnet , a pair of pole pieces being made of a soft magnetic material and sandwiching the magnet from either side in the oscillation axis, and a pair of weights being made of a non-magnetic material and sandwiching the pair of pole pieces from either side in the oscillation axis, the electromagnetic driver including a pair of coils , each in a cylindrical shape, spaced apart from each other along the oscillation axis, and a yoke in a tubular shape disposed radially outside the pair of coils , the yoke being made of a soft magnetic material and projecting outward beyond the pair of coils along the oscillation axis, and the yoke having one or more cutouts along each edge in the direction of the oscillation axis; and characterized in that : along the oscillation axis, the yoke has an average length greater than or equal to a sum of an end-to-end length of the pair of pole pieces and the double of a one-way amplitude of oscillation of the mover , and along the oscillation axis, the yoke has a minimum length greater than or equal to a sum of an end-to-end length of the pair of pole pieces and the double of a one-way amplitude of oscillation of the mover . along the oscillation axis, the yoke has an average length greater than or equal to a sum of an end-to-end length of the pair of pole pieces and the double of a one-way amplitude of oscillation of the mover , and along the oscillation axis, the yoke has a minimum length greater than or equal to a sum of an end-to-end length of the pair of pole pieces and the double of a one-way amplitude of oscillation of the mover . <EOS>