| 摘要 |
<p>A lens barrel has a cam ring (5) for positioning a first lens frame (11) relative to the optical axis direction; a first correction housing (1) formed of a material having a linear expansion coefficient different from that of the cam ring (5) and positioning the cam ring (5) relative to the optical axis direction; and a second correction housing (2) formed of a material having linear expansion coefficient different from that of a moving frame (6) and positioning a second lens frame (21) relative to the optical axis direction. Along with a dimensional variation in the axial direction of the first correction housing (1) caused by a variation in temperature, the cam ring (5) moves in the optical axis direction and first and second lenses (10, 20) move in the optical axis direction. Also, along with a dimensional variation in the axial direction of the second correction housing (2) caused by the variation in temperature, the second lens (20) moves in the optical axis direction. As a result, the distance between the first lens (10) and the second lens (20) varies.</p> |
