IMAGE-PICKUP APPARATUS AND CONTROL METHOD THEREOF

• US 20090040354A1
• Filed: 08/01/2008
• Published: 02/12/2009
• Est. Priority Date: 08/09/2007
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Takanashi, Hideya
• Granted Patent: US 7,940,323 B2
• Time in Patent Office: Days
• US Class Current: 348/308
• CPC Class Codes: H04N 23/672 based on the phase difference signals

Abstract

An image-pickup apparatus 100 includes a focus detecting part 7 that detects focus information indicating a focus state of an image-pickup optical system, a color measuring part 14a, 14b, and 15 that detects color measurement information related to a color of an object, a controlling part 6 that generates controlling information used in focus control using the focus information and the color measurement information, and a memory 9 that stores the color measurement information. When the color measurement information stored in the memory 9 is referred to as a first color measurement information, and color measurement information which is detected by the color measuring part after the first color measurement information is detected is referred to as a second color measurement information, the controlling part performs a determination related to a delay in the acquisition of the second color measurement information relative to the acquisition of the focus information, and, based on the determination result, switches the color measurement information used in generating the controlling information between the first color measurement information and the second color measurement information.

Claims

1. An image-pickup apparatus comprising:

a focus detecting part that detects focus information indicating a focus state of an image-pickup optical system;

a color measuring part that detects color measurement information related to a color of an object;

a controlling part that generates controlling information used in focus control using the focus information and the color measurement information; and

a memory that stores the color measurement information,

wherein, when the color measurement information stored in the memory is referred to as a first color measurement information, and color measurement information which is detected by the color measuring part after the first color measurement information is detected is referred to as a second color measurement information, the controlling part performs a determination related to a delay in the acquisition of the second color measurement information relative to the acquisition of the focus information, and, based on the determination result, switches the color measurement information used in generating the controlling information between the first color measurement information and the second color measurement information.

2. The image-pickup apparatus according to claim 1,

wherein the determination related to the delay is a determination of whether or not the second color measurement information has been acquired when the focus information is acquired, and

if the second color measurement information has been acquired, the controlling part generates the controlling information using the focus information and the second color measurement information, and if the second color measurement information has not been acquired, the controlling part generates the controlling information using the focus information and the first color measurement information.

3. The image-pickup apparatus according to claim 1,

wherein the image-pickup apparatus has a continuous image-pickup mode which performs continuous image-pickup of a plurality of still images, and

the controlling part switches the color measurement information used in generating the controlling information in the continuous image-pickup mode.

4. The image-pickup apparatus according to claim 1,

wherein, if the second color measurement information has not been acquired when the focus information is acquired, the determination related to the delay is a determination of whether or not the second color measurement information can be acquired within a predetermined time, and

if the second color measurement information can be acquired within the predetermined time, the controlling part generates the controlling information using the focus information and the second color measurement information, and if the second color measurement information cannot be acquired within the predetermined time, the controlling part generates the controlling information using the focus information and the first color measurement information.

5. The image-pickup apparatus according to claim 4,

wherein the image-pickup apparatus has a continuous image-pickup mode which performs continuous image-pickup of a plurality of still images,

the controlling part switches the color measurement information used in generating the controlling information in the continuous image-pickup mode, and

the predetermined time is a time corresponding to a target continuous image-pickup speed set for the continuous image-pickup mode.

6. An method for controlling an image-pickup apparatus comprising the steps of:

detecting focus information which indicates a focal state of an image-pickup optical system;

detecting color measurement information related to a color of an object;

generating controlling information used in focus control using the focus information and the color measurement information; and

storing the color measurement information in a memory,

wherein, when the color measurement information stored in the memory is referred to as a first color information measurement, and color measurement information which is detected after the first color measurement information is detected is referred to as a second color measurement information, in the step of generating the controlling information, a determination related to a delay in the acquisition of the second color measurement information relative to the acquisition of the focus information is performed, and, based on the determination result, the color measurement information used in generating the controlling information is switched between the first color measurement information and the second color measurement information.