Lens Barrel with Collapsible Lens Groups, and Image Pickup Apparatus

Content Provider	The Lens
Abstract	A lens barrel which reliably retracts a retractable lens group without increasing thickness in a direction of an optical axis before an adjoining lens group is housed. A first lens holding member holds a first lens. A cam cylinder drives the first holding member along the optical axis. At a shooting position, the second holding member that holds a second lens lies on an optical axis, and at a collapsed position, the second holding member retracts to a retracted position by engaging with a moving member that moves toward the image plane in response to movement of the cam cylinder toward the image plane. The cam cylinder has a cam groove, on which the first holding member moves toward a subject before the second holding member starts retracting in a process of shifting from the shooting position to the collapsed position.
Related Links	https://www.lens.org/lens/patent/011-174-635-716-395/frontpage
Language	English
Publisher Date	2019-11-12
Access Restriction	Open
Content Type	Text
Resource Type	Patent
Jurisdiction	United States of America
Date Applied	2017-01-13
Agent	Cowan, Liebowitz & Latman, P.c.
Applicant	Canon Kk
Application No.	201715405657
Claim	A lens barrel comprising: a first holding member of an inserted lens group, configured to hold an inserted lens; a cam cylinder configured to drive said first holding member in a direction of an optical axis by a cam mechanism; and a second holding member of a retracting lens group located immediately adjacent to the inserted lens group along the optical axis, and configured to hold a retracting lens disposed closer to an image plane than the inserted lens, wherein at a shooting position, said second holding member is configured to lie on the optical axis, and during a process of retracting, said second holding member retracts to a retracted position away from the optical axis in a direction perpendicular to the optical axis in response to movement of said cam cylinder toward the image plane, and wherein a cam groove is formed on the cam cylinder, said groove is configured to move the first holding member in a direction toward a subject relatively to the cam cylinder so that the first holding member does not interfere with said second holding member during a process of retracting the lens barrel from a WIDE position to the collapsed position before said second holding member starts retracting to the retracted position as part of the process of retracting the lens barrel from the WIDE position to the collapsed position. The lens barrel according to claim 1 , wherein in the process of shifting from the shooting position to the collapsed position, said second holding member starts retracting to the retracted position after said first holding member has moved to a position closest to the subject relatively to the outside cam cylinder. The lens barrel according to claim 1 , wherein in the process of shifting from the shooting position to the collapsed position, said first holding member moves to a position on the optical axis, adjacent to a collapsed position to which said second holding member has retracted, without moving toward the subject relatively to an image pickup element. The lens barrel according to claim 1 , wherein in the process of shifting from the shooting position to the collapsed position, said second holding member moves to a waiting position on the optical axis and then moves in a direction perpendicular to the optical axis to arrive at the retracted position. The lens barrel according to claim 1 , wherein the moving member is a straight advance cylinder that is disposed on an inner peripheral side of said cam cylinder and caused to move in the direction of the optical axis by rotation of the outside cam cylinder, and wherein in the process of shifting from the shooting position to the collapsed position, said second holding member moves to the retracted position by engaging with a straight advance cylinder that is caused to move toward the image plane by rotation of said cam cylinder. The lens barrel according to claim 1 , wherein in a relationship with the outside cylinder in the direction of the optical axis, a position assumed by said first holding member at the collapsed position is the same as or closer to the subject than a position assumed by said first holding member at a shooting position at which a focal length is the shortest. The lens barrel according to claim 1 , further comprising: a first driving unit configured to drive said cam cylinder; and a second driving unit configured to drive said second holding member in the direction of the optical axis independently of said first driving unit, wherein a rack that constitutes said second holding member is fitted on a screw formed integrally with an output shaft of a motor that constitutes said second driving unit. The lens barrel according to claim 1 , wherein after said second holding member retracts from the optical axis, said first holding member moves to a position on the optical axis from which said second holding member has retracted. The lens barrel in accordance with claim 1 , wherein the groove is further configured to, after moving the first holding member in the direction toward the subject relatively to the outside came cylinder, subsequently move the first holding member in an opposite direction toward the image plane relatively to the outside cam cylinder during the process of retracting the lens barrel from the shooting position to the collapsed position. An image pickup apparatus with a lens barrel, wherein the lens barrel comprises: a first holding member of an inserted lens group that holds an inserted lens; a cam cylinder configured to drive the first holding member in a direction of an optical axis by a cam mechanism; and a second holding member of a retracting lens group located immediately adjacent to the inserted lens group along the optical axis, and configured to hold a retracting lens disposed closer to an image plane than the inserted lens, wherein at a shooting position, said second holding member is configured to lie on the optical axis, and during a process of retracting, said second holding member retracts to a retracted position away from the optical axis in a direction perpendicular to the optical axis in response to movement of said cam cylinder toward the image plane, and wherein a cam groove is formed on the cam cylinder, said groove is configured to move the first holding member in a direction toward a subject relatively to the cam cylinder so that the first holding member does not interfere with said second holding member during a process of retracting the lens barrel from a WIDE position to the collapsed position before said second holding member starts retracting to the retracted position as part of the process of retracting the lens barrel from the WIDE position to the collapsed position. The lens barrel in accordance with claim 10 , wherein the groove is further configured to, after moving the first holding member in the direction toward the subject relatively to the outside came cylinder, subsequently move the first holding member in an opposite direction toward the image plane relatively to the outside cam cylinder during the process of retracting the lens barrel from the shooting position to the collapsed position.
CPC Classification	OPTICAL ELEMENTS; SYSTEMS OR APPARATUS APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM;APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES;ACCESSORIES THEREFOR
Examiner	Marin Pichler
Extended Family	072-388-720-168-756 011-174-635-716-395 026-918-184-573-447 006-848-630-938-893
Patent ID	10473885
Inventor/Author	Kudoh Tomoyuki
IPC	G02B7/10 G02B7/02 G02B15/14
Status	Active
Owner	Canon Kabushiki Kaisha
Simple Family	072-388-720-168-756 011-174-635-716-395 026-918-184-573-447 006-848-630-938-893
CPC (with Group)	G02B7/023 G02B15/145 G03B17/045 G02B7/102 G02B7/10
Issuing Authority	United States Patent and Trademark Office (USPTO)
Kind	Patent/New European patent specification (amended specification after opposition procedure)