Photometric device, imaging device, and camera

Abstract

A photometric device includes: an imaging unit that captures an image formed by an optical system, with a marker capable of switching between display and non-display disposed in a light path of the optical system; and a correction unit that, based upon a difference between a first image captured by the imaging unit in a state where the marker is displayed and a second image captured by the imaging unit in a state where the marker is not displayed, performs a correction of a third image that is different from the first image and the second image.

What is claimed is: 
     
         1 . A photometric device, comprising:
 an imaging unit that captures an image formed by an optical system, with a marker capable of switching between display and non-display disposed in a light path of the optical system; and   a correction unit that, based upon a difference between a first image captured by the imaging unit in a state where the marker is displayed and a second image captured by the imaging unit in a state where the marker is not displayed, performs a correction of a third image that is different from the first image and the second image.   
     
     
         2 . A photometric device according to  claim 1 , wherein:
 based upon the difference, the correction unit detects a position of an image of the marker in an image captured by the imaging unit and, based upon the detection result, performs the correction.   
     
     
         3 . A photometric device according to  claim 2 , wherein:
 based upon the position of the image of the marker, the correction unit performs the correction for an image of a portion in the third image corresponding to the position.   
     
     
         4 . A photometric device according to  claim 1 , wherein:
 the first image and the second image are captured by the imaging unit under a same image-capturing condition.   
     
     
         5 . An imaging device, comprising:
 an imaging unit that captures an image formed by an optical system, with a marker capable of switching between display and non-display disposed in a light path of the optical system;   a detection unit that, based upon an image captured by the imaging unit in a state where the marker is displayed, detects a position of an image of the marker formed on an imaging plane of the imaging unit; and   a recording unit that records the position of the image of the marker detected by the detection unit.   
     
     
         6 . An imaging device according to  claim 5 , wherein:
 the detection unit detects the position of the image of the marker based upon a first image captured by the imaging unit in a state where the marker is displayed and a second image captured by the imaging unit in a state where the marker is not displayed.   
     
     
         7 . An imaging device according to  claim 6 , further comprising:
 a correction unit that, based upon the position of the image of the marker recorded in the recording unit, performs a correction of a third image among images captured by the imaging unit, with the third image different from the first image and the second image.   
     
     
         8 . An imaging device according to  claim 7 , wherein:
 based upon the position of the image of the marker, the correction unit performs the correction for an image of a portion in the third image corresponding to the position.   
     
     
         9 . An imaging device according to  claim 6 , wherein:
 the first image and the second image are captured by the imaging unit under a same image-capturing condition.   
     
     
         10 . An imaging device according to  claim 5 , further comprising:
 a control unit that controls on and off of a power of the imaging device, wherein:   the detection unit detects the position of the image of the marker when the power is turned off and   the recording unit records the position of the image of the marker when the detection unit detects the position.   
     
     
         11 . A camera comprising:
 a first image generating unit that generates a first image that contains a subject image and a autofocus marker superimposed on the subject image;   a buffer memory that stores the first image;   a second image generating unit that generates a second image by erasing the autofocus marker from the first image stored in the buffer memory;   a face detection unit that performs face detection using the second image; and   a tracking unit that tracks a subject using the output of the face detection unit.   
     
     
         12 . A camera according to  claim 11 , further comprising:
 a third image generating unit that generates a third image by synthesizing a plurality of the second images through template matching, wherein:   the face detection unit performs face detection using the third image.   
     
     
         13 . A camera according to  claim 11 , wherein:
 the second image generating unit erases the autofocus marker from the first image by replacing a pixel on the autofocus marker with its adjacent pixel.   
     
     
         14 . A camera comprising:
 a first image generating unit that generates a first image that contains a subject image and an autofocus marker superimposed on the subject image;   a memory that stores the first image;   a second image generating unit that generates a second image by erasing the autofocus marker from the first image stored in the memory; and   a face detection unit that performs face detection using the second image.