Olympus Imaging Corporation

Takahiro Kaneta

Tatsuo Takanashi

Yasunari Shimazaki

A lens barrel includes a first member which has a first sliding-contact surface and an opening formed in the first sliding-contact surface; a second member which has a second sliding-contact surface and moves relative to the first member, the second sliding-contact surface being placed in sliding contact with the first sliding-contact surface; a photodetector provided in the opening of the first member, facing the second sliding-contact surface, to detect relative movement between the first member and the second member; and a lubricant sump portion which, being provided in the first member, has a lubricant sump space on opposite sides of the opening interposing the opening therebetween in a direction of the relative movement.

Lens barrel

The inventive lens barrel comprises: a first group frameretaining the first group lenswith a positive refractivity and being movable on the optical axis; a second group frameretaining the second group lenswith a negative refractivity and being movable on the optical axis; a third group frameretaining an aperture diaphragmand the third group lens, and being movable on the optical axis and pivotable perpendicular to the optical axis in such a manner that the third group framecan move the aperture diaphragmand the third group lensto the position on the optical axis O in a imaging standby state, in which the lens barrelis extended, and move them to the position out of the optical axis O in the retracted state, in which the lens barrelis shortened; and, a fourth group frameretaining the fourth group framewith a positive refractivity, and being movable on the optical axis, and being arranged such that it can retract the aperture diaphragmand the third group lensto a space between the object side end of the second group image side lens of the second group lens, which has a relatively smaller outer shape, and the image side end of the fourth group lens, in view from the direction perpendicular to the optical axis, under the retracted state.

Growing community of inventors

Hino, Japan

Takahiro Kaneta