Patent attributes
A lens barrel includes an imaging optical system having front and rear optical elements with a spring installed therebetween; a reference barrel which includes a forward-facing limit surface and a rearward-facing limit surface; a first position control mechanism which includes a first rotational member and a first limit member, and varies a position of the front optical element in the optical axis direction relative to the reference barrel; and a second position control mechanism which includes a second rotational member and a second limit member, and varies a position of the rear optical element in the optical axis direction relative to the reference barrel. The first limit member is brought into contact with the rearward-facing limit surface by a forward biasing force of the spring while the second limit member is brought into contact with the forward-facing limit surface by a rearward biasing force of the spring.