JP2007206304A5 - - Google Patents

Claims (6)

A rotatable lead screw,
A holding member having a rack for holding an optical element and converting rotation of the feed screw into driving force in the optical axis direction;
A guide member for guiding the holding member in the optical axis direction;
The rack includes a rack tooth that meshes with the feed screw, and a pressure tooth that is rotatably attached to the rack and is biased to be pressed against the feed screw from the opposite side of the rack tooth and meshes with the feed screw. Having a member,
In the optical axis direction, the optical element is disposed on the first side with respect to the rack,
The feed screw is a left-hand screw;
In the optical axis direction view from the first side, the rack and the feed screw are located in a region on the right side of the optical axis, and the pressure tooth member is located outside the rack tooth with respect to the optical axis. An optical device characterized by that. 2. The optical apparatus according to claim 1, wherein the guide member is located on an outer side with respect to the optical axis than the feed screw in the right region when viewed in the optical axis direction from the first side. .   The feed screw and the rack are disposed in one of the right region and the region above and below the optical axis, and the guide member is disposed in the other region of the right region. The optical apparatus according to claim 1, wherein the optical apparatus is disposed. The first moment generated by the weight of the optical element and the pressure tooth member are pressed against the feed screw as the moments around the guide member acting on the holding member in the optical axis direction view, respectively. And the second moment generated by the pull-in force toward the feed screw acting on the rack acts in the same rotational direction.
A tilting force generated in the holding member when the thread of the feed screw has a different angle with respect to the rack tooth at the meshing portion of the rack tooth and the feed screw causes an inclination of the holding member on the optical element side. 4. The optical apparatus according to claim 1, wherein the optical apparatus acts in a direction in which the portion is lowered.   The rack includes an opening for inserting the feed screw in a radial direction between the rack tooth and the pressure tooth member, and the opening is formed downward. The optical apparatus according to any one of 1 to 4. The first moment generated by the weight of the optical element and the pressure tooth member are pressed against the feed screw as the moments around the guide member acting on the holding member in the optical axis direction view, respectively. And the second moment generated by the pulling force toward the feed screw acting on the rack acts in opposite directions of rotation,
A tilting force generated in the holding member when the thread of the feed screw has a different angle with respect to the rack tooth at the meshing portion of the rack tooth and the feed screw causes an inclination of the holding member on the optical element side. 4. The optical apparatus according to claim 1, wherein the optical apparatus acts in a direction in which the portion is lowered.