the optical axis direction via a drive mechanism described later guide shaft 19 functions to prevent the rotation of lens holding frame 13 around the optical axis and functions as a guide member for moving lens holding frame 13 in the optical axis direction with excellent precision a position sensor of a well known ferromagnetic thin film reluctance element type hereinafter referred to as 34 mr sensor 34 is provided to detect the moving distance of the lens l1 that is since the moving distance of lens l1 is also the moving distance of lens holding frame 13 and guide shaft 19 a magnetic reluctance element 20 comprising an mr sensor is arranged in internal barrel 17 and magnetic rods of north and south magnetic poles are arranged at predetermined intervals on guide shaft 19 so as to detect the moving distance of lens holding frame 13 in cooperation with said magnetic reluctance element 20 reference number 18 refers to a working member friction bonded to drive shaft 14 and piezoelectric element 15 is disposed between said working member 18 and the extension 17a of internal barrel 17 the piezoelectric element 15 and working member 18 and piezoelectric element 15 and extension 17a of internal barrel 17 are fixedly bonded together with adhesive a hole 18a is formed in working member 18 through which passes drive shaft 14 fig2 shows an enlargement of the contact area between drive shaft 14 and working member 18 viewed in section along the y y line of fig1 in fig2 the.