Patent ID: 6128142
Filing Date: 2000-10-03
Classification: G02B

Abstract:
A lens device, comprising:a lens;a lens frame holding the lens, the lens frame including a cam follower pin to receive a force to move along an optical axis;a cylindrical cam surrounding the lens and the lens frame, the cylindrical cam comprising a cam groove including a first cam surface and a second cam surface opposed to the first cam surface which abut against the cam follower pin to move the lens frame along the optical axis by rotation of the cylindrical cam with respect to the optical axis,wherein the respective first and second cam surfaces are divided into a plurality of surfaces, and a parting line is formed at a location where the respective first and second cam surfaces are divided, the parting line extending between the opposed cam surfaces, andeach of the plurality of divided first cam surfaces have a same angle of inclination,the plurality of divided second cam surfaces comprise a first divided second cam surface having an angle of inclination away from the first cam surface, a second divided second cam surface having an angle of inclination toward the first cam surface, anda portion of the second cam surface joining the first divided second cam surface and the second divided second cam surface is not inclined with respect to the first cam surface.