Lens apparatus and image-taking system with multiple focus modes

• US 7,443,441 B2
• Filed: 12/30/2004
• Issued: 10/28/2008
• Est. Priority Date: 01/05/2004
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hiraoka, Akira
• Primary Examiner(s): Ye; Lin
• Assistant Examiner(s): Daniels; Anthony J
• Application Number:
  US11/027,374
• Publication Number:
  US 20050146635A1
• Time in Patent Office: 1,398 Days
• Field of Search: 348345-356, 396/89, 396/131
• US Class Current: 348/345
• CPC Class Codes: G02B 7/102 controlled by a microcomputer cameras with interchangeable lenses G03B17/14

Abstract

A lens apparatus is disclosed, in which the MF operation can be performed at any time during the AF operation. The lens apparatus comprises a lens system including a front focusing lens, a magnification-varying lens and a rear focusing lens, a first operating member, and a second operating member. The front focusing lens is driven for manual focus in accordance with the operation of the first operating member in the first mode, the rear focusing lens is driven for automatic focus in the second mode. The focus mode is switched from the second mode to the third mode in accordance with the operation of the second operating member. The rear focusing lens is driven in accordance with the operation of the second operating member in the third mode.

Claims

1. A lens apparatus comprising, in order from an object side:

a front focusing lens unit;

a magnification-varying lens unit; and

a rear focusing lens unit,

wherein the lens apparatus has the following focus modes;

a first focus mode in which the front focusing lens unit that is mechanically connected with a first operating unit is driven in accordance with an operation of the first operating unit;

a second focus mode in which automatic focus is performed by driving the rear focusing lens unit using an actuator; and

a third focus mode in which the rear focusing lens unit is driven in accordance with an operation of a second operating unit that is different from the first operating unit,

wherein an operation of the second operating unit in the second focus mode changes the focus mode from the second focus mode to the third focus mode, wherein the rear focusing lens unit is driven in accordance with an operation amount of the second operating unit in the third focus mode,

wherein the lens apparatus comprising a connecting mechanism which is selectively set to a first state in which the actuator is connected with the rear focusing lens unit and the second operating unit is not connected with the rear focusing lens unit, and a second state in which the second operating unit is mechanically connected with the rear focusing lens unit and the actuator is not connected with the rear focusing lens unit, and

wherein the first state is set in the second focus mode, and the second state is set in the third focus mode.

2. The lens apparatus according to claim 1, further comprising a controller which controls a switching operation of the connecting mechanism from the first state to the second state in accordance with switching from the second focus mode to the third focus mode.