Focus adjustment method, focus adjustment apparatus, and control method thereof

Claim 2

A focus adjustment apparatus comprising: a face position detection unit (120) for detecting a position at which exists at least a face of a person in a frame using an image signal obtained from an image sensor (103) which photoelectrically converts an object image captured by a photographing optical system (101); a focus control unit (114) for controlling the photographing optical system by referencing an in-focus position of the object image obtained in a focus detection area for detecting a focus state of the object image positioned in the frame; and a control unit (112) for controlling the focus control unit to reference at least either an in-focus position obtained in a first focus detection area in which the person's face is present or an in-focus position obtained in a second focus detection area in which it is estimated that the person's body is present determining from the position of the person's face, wherein the control unit controls the focus control unit to reference the in-focus position obtained in the first focus detection area if a difference between the in-focus position in the first focus detection area and the in-focus position in the second focus detection area is equal to or less than a pre-determined value.

Claim 3

A focus adjustment apparatus comprising: a face position detection unit (120) for detecting a position at which exists at least a face of a person in a frame using an image signal obtained from an image sensor (103) which photoelectrically converts an object image captured by a photographing optical system (101); a focus control unit (114) for controlling the photographing optical system by referencing an in-focus position of the object image obtained in a focus detection area for detecting a focus state of the object image positioned in the frame; a control unit (112) for controlling the focus control unit to reference at least either an in-focus position obtained in a first focus detection area in which the person's face is present or an in-focus position obtained in a second focus detection area in which it is estimated that the person's body is present determining from the position of the person's face; and a display unit (110) for displaying an image obtained from the image sensor, wherein the focus control unit focuses on and displays the position of the face detected by the face position detection unit if the focus control unit controls the photographing optical system by referencing the in-focus position in either the first focus detection area or the second focus detection area.

Claim 4

A focus adjustment method comprising: a face position detection step (S303) of detecting a position at which exists at least a face of a person in a frame using an image signal obtained from an image sensor (103) which photoelectrically converts an object image captured by a photographing optical system; a focus control step (S311, S313) of controlling the photographing optical system by referencing an in-focus position of the object image obtained in a focus detection area for detecting a focus state of the object image positioned in the frame; a control step (S311, S313) of controlling such that in the focus control step at least either an in-focus position obtained in a first focus detection area in which the person's face is present or an in-focus position obtained in a second focus detection area in which it is estimated that the person's body is present determining from the position of the person's face is referenced; and a determining step of determining the reliability with which the person's face can be focused on in the first focus detection area, wherein the control step controls such that the focus control step references either the in-focus position obtained in the first focus detection area or the in-focus position obtained in the second focus detection area based the determination results of the determining step.

Claim 5

A focus adjustment method comprising: a face position detection step (S303) of detecting a position at which exists at least a face of a person in a frame using an image signal obtained from an image sensor (103) which photoelectrically converts an object image captured by a photographing optical system (101); a focus control step (S311, S313) of controlling the photographing optical system by referencing an in-focus position of the object image obtained in a focus detection area for detecting a focus state of the object image positioned in the frame; and a control step (S311, S313) of controlling such that in the focus control step at least either an in-focus position obtained in a first focus detection area in which the person's face is present or an in-focus position obtained in a second focus detection area in which it is estimated that the person's body is present determining from the position of the person's face is referenced, wherein the control step controls the focus control step to reference the in-focus position obtained in the first focus detection area if a difference between the in-focus position in the first focus detection area and the in-focus position in the second focus detection area is equal to or less than a pre-determined value.

Claim 6

A focus adjustment method comprising: a face position detection step (S303) of detecting a position at which exists at least a face of a person in a frame using an image signal obtained from an image sensor (103) which photoelectrically converts an object image captured by a photographing optical system (101); a focus control step (S311, S313) of controlling the photographing optical system by referencing an in-focus position of the object image obtained in a focus detection area for detecting a focus state of the object image positioned in the frame; a control step (S311, S313) of controlling such that in the focus control step at least either an in-focus position obtained in a first focus detection area in which the person's face is present or an in-focus position obtained in a second focus detection area in which it is estimated that the person's body is present determining from the position of the person's face is referenced; and a display step of displaying an image obtained from the image sensor, wherein the position of the face detected in the face position detection step is focused on and displayed in the focus control step if the focus control step controls the photographing optical system by referencing the in-focus position in either the first focus detection area or the second focus detection area.

Claim 7

A focus adjustment apparatus comprising: a face detection unit (120) for detecting a position at which exists at least a face of an object using an image signal obtained from an image sensor (103) which photoelectrically converts an object image captured by a photographing optical system (101); a focus detection unit (114) for detecting a plurality of in-focus positions of the photographing optical system in a focus detection area in which it is estimated that a body is present corresponding to the face of the object detected by the face detection unit; and a control unit (112) for controlling movement of the photographing optical system based on at least one of the in-focus positions obtained in the focus detection area, wherein the control unit controls so as to move the photographing optical system to the in-focus position corresponding to the farthest distance, from among the plurality of in-focus positions detected by the focus detection unit.

Claim 8

The focus adjustment apparatus according to claim 7, wherein the focus detection unit sets a plurality of focus detection areas in which the body is expected to be present with respect to a face of an object detected by the face detection unit, and in-focus positions of the photographing optical system are detected in each of the plurality of focus detection areas.

Claim 9

The focus adjustment apparatus according to claim 7, further comprising: an estimation unit(112) for estimating an object distance based on the size of a face of an object detected by the face detection unit, wherein the control unit removes from the in-focus position when moving the photographing optical system any of the plurality of in-focus positions detected by the focus detection unit that are not in-focus positions within the object field depth of the object distance obtained by the estimation unit.

Claim 10

The focus adjustment apparatus according to claim 7, wherein the focus detection unit detects an in-focus position of the photographing optical system in the focus detection areas in which the body is expected to be present with respect to the face of the object if an in-focus position cannot be detected for the photographing optical system in the focus detection area corresponding to the position in which the face of the object detected by the face detection unit is present.

Claim 11

The focus adjustment apparatus according to claim 7, wherein the control unit is provided with a display control unit for controlling a display section so as to perform in-focus display at a corresponding face position when the photographing optical system is controlled so as to move to an in-focus position of the photographing optical system in a focus detection area where the body is expected to be present with respect to a face of an object.

Claim 12

A focus adjustment apparatus comprising: a face detection unit (120) for detecting face information of an object using an image signal obtained by photoelectrically converting an object image captured by a photographing optical system (101); an estimation unit (112) for estimating an object distance from the face information detected by the face detection unit; a focus detection unit (114) for detecting an in-focus position of the photographing optical system based on the image signal; and a control unit (112) for controlling so as to move the photographing optical system to the detected in-focus position, wherein the control unit selects the in-focus position to which to move the photographing optical system from among a plurality of in-focus positions based on the estimated object distance if the plurality of in-focus positions are detected.

Claim 13

The focus adjustment apparatus according to claim 12, wherein the focus detection unit detects an in-focus position of the photographing optical system based on an image signal in a focus detection area based on face information detected by the face detection unit.

Claim 14

The focus adjustment apparatus according to claim 12, wherein the control unit selects an in-focus position in an object field depth of the estimated object distance when a plurality of in-focus positions is detected.

Claim 15

The focus adjustment apparatus according to claim 12, wherein the control unit selects an in-focus position close to the estimated object distance when a plurality of in-focus positions is detected.

Claim 16

The focus adjustment apparatus according to claim 12, wherein the face information includes at least information on the size of a face, and the estimation unit estimates the object distance based on the face size information.

Claim 17

A control method for a focus adjustment apparatus comprising: a face detection step (S303) of detecting a position at which exists at least a face of an object using an image signal obtained by photoelectrically converting an object image captured by a photographing optical system (101); a focus detection step (S307) of detecting a plurality of in-focus positions of the photographing optical system in a focus detection area in which it is estimated that a body is present corresponding to the face of the object detected in the face detection step; and a control step (S311, S313) of controlling movement of the photographing optical system based on at least one of the in-focus positions obtained in the focus detection area, wherein the control step controls so as to move the photographing optical system to the in-focus position corresponding to the farthest distance, from among the plurality of in-focus positions detected in the focus detection step.

Claim 18

A control method for a focus adjustment apparatus comprising: a face detection step (S303) of detecting face information of an object using an image signal obtained by photoelectrically converting an object image captured by a photographing optical system (101); an estimation step of estimating an object distance from the face information detected in the face detection step; a focus detection step of detecting an in-focus position of the photographing optical system based on the image signal; and a control step of controlling so as to move the photographing optical system to the detected in-focus position, wherein the control unit selects the in-focus position to which to move the photographing optical system from among a plurality of in-focus positions based on the estimated object distance if the plurality of in-focus positions are detected.

Claim 19

A focus adjustment apparatus comprising: a face position detection unit (120) for detecting a position at which exists at least a face of a person in a frame using an image signal obtained from an image sensor (103) which photoelectrically converts an object image captured by a photographing optical system (101); a focus detection unit (122) for detecting an in-focus position of the photographing optical system in at least one of a first focus detection area in which the person's face detected by said face position detection unit is present and a second focus detection area in which it is estimated that the person's body corresponding to the person's face detected by said face position detection unit is present; and a control unit (114) for controlling a movement of the photographing optical system based on at least one of in-focus positions obtained from the first and second focus detection areas, wherein the second focus detection area is larger than the first focus detection area.