| 摘要 |
PURPOSE:To eliminate the friction resistance by sliding and the clatters, etc., by fitting by supporting a connecting member which is concentrically disposed in a lens barrel movably in the lens barrel by means of elastic members displaceable in an optical axis direction and fixing lens elements to the connecting member. CONSTITUTION:A lens holding frame 3 is disposed in an outer cylinder 7 of the lens barrel and lenses 4a, 4b are fixed to this holding frame. The lens holding frame 3 is supported in the outside cylinder 7 of the lens barrel by means of two sheets of elastic flat plates. Two sheets of the elastic flat plates 1, 2 are disposed in parallel so that the holding frame 3 can be moved only in the Z direction. A permanent magnet 9 is fixed to the outer peripheral part of the lens holding frame 3 and an electromagnet constituted by winding a coil 6 in an iron core 5 is disposed to face the permanent magnet 9. Then, attraction force and repulsion force are generated with the permanent magnet 9 by changing the energization state of the coil 6. The holding frame 3 to which the permanent magnet 9 is fixed obtains the thrust to the outside cylinder 7 and moves in the optical axis direction. The friction by sliding and the clatter and backlash by the fitting are decreased in this way and, therefore, the smooth movement of the lens group is assured. |
