Drive device, lens barrel, image pickup apparatus, lens drive method and method of producing shape memory alloy

Abstract

A lens barrel, an image pickup apparatus, a lens drive method and a method of producing a shape memory alloy used for the drive device are disclosed. A drive device includes: a lens group for guiding light from a subject; a shape memory alloy adopted to be deformed by an electricity supplied to the shape memory alloy, for moving the lens group in a direction of an optical axis; and electricity-supply controlling means for controlling an amount of the electricity supplied to the shape memory alloy; and a detecting means for detecting whether a movement of the lens group starts or not. In the drive device, a movement amount of the lens group in the direction of the optical axis is controlled based on the amount of electricity supplied when the detecting means detects the movement of the lens group.

1 - 17 . (canceled) 
     
     
         18 . A method of producing shape memory alloy for use in a drive apparatus comprising a driven body, a shape memory alloy in contact with the driven body, a heating section for heating the shape memory alloy, a controlling section for controlling a drive of a driven body by controlling the heating section, the method comprising:
 a step of applying an aging treatment to the shape memory alloy which is in contact with the driven body, after the drive apparatus has been assembled, the aging treatment repeating a predetermined number or more of times of heating and no-heating processes.   
     
     
         19 . The method of producing shape memory alloy of  claim 18 , wherein the shape memory alloy is heated by applying an electric current to the shape memory alloy. 
     
     
         20 . The method of producing shape memory alloy of  claim 18 , wherein the controlling section controls the heating section to heat the shape memory alloy, for applying the aging treatment to the shape memory alloy.