Focus adjusting mechanism for a camera

A focus adjusting mechanism for a camera includes a fixed lens and an auxiliary lens carried by a supporting member. The supporting member is movable between an advanced position for holding the auxiliary lens in the optical path of said fixed lens and a retracted position for holding the auxiliary lens out of the optical path of the fixed lens. The supporting member is biased from its retracted to advanced position but the movement thereof toward the advanced position is normally restrained by a piezoelectric bender element provided within the locus of said supporting member. The piezoelectric bender element is transformed and moved out of the locus of the supporting member for releasing the restraint when a proper voltage is applied to the electric bender element. A power supply circuit is provided for generating the proper voltage to be applied to the piezoelectric bender element. A control circuit is also provided for applying the proper voltage to the piezoelectric bender element when the object to be photographed is at the predetermined distance from the camera.