Patent ID: 7633692
Filing Date: 2009-12-15
Classification: G03F

Abstract:
1. An optical apparatus comprising: an optical element; and a moving apparatus configured to move the optical element, the moving apparatus including, a cylindrical cam barrel including a cam groove; a moving member adapted to be rotated relative to the cam barrel and moved in an axis direction of the cam barrel; and a bearing for supporting a cam follower fixed on the moving member with the cam groove, wherein when viewed from the axis direction of the cam follower, a contact position between the bearing and the cam groove is located closer to the side of the rotation center axis of the moving member than the axis line of the follower under force exerted in a axis direction of the cam barrel against the moving member, wherein a straight line connecting the contact position and the rotation center axis is substantially parallel on average to the axis line of the cam follower in a horizontal plane passing through the contact position, within a range of movement when the bearing and the cam follower are moved along the cam groove, wherein a straight line connecting the contact position and the rotation center axis is substantially parallel to the axis line of the support shaft in a horizontal plane passing through the contact position.