JP2009118515A - Electronic camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable an image display means with less pixel count to check whether an image, which is going to be shot by a solid-state image sensing device with more pixel count, is in focus, and to enable high-precision manual focusing. <P>SOLUTION: The solid-state image sensing device (CCD) 18 employed for this electronic camera has a larger number of pixels than that of a liquid crystal monitor 14. This camera has a manual focus function to perform focusing when a focus adjustment member is manually operated. In response to the manual operation of the focus adjustment member, a partial image is extracted from the entire image to be photographed, and an image signal representing the extracted partial image is output to the liquid crystal monitor 14 as it is or after it is thinned with a thinning rate smaller than a usual thinning rate. This enables the extracted partial image to be magnified and displayed on the liquid crystal monitor 14, and enables high-precision focus state checking. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic camera, and more particularly to an electronic camera including an image display device such as a liquid crystal monitor that can be used as a viewfinder.

  Conventionally, the number of pixels of a solid-state imaging device used in an electronic camera such as a digital camera is small, from 300,000 pixels to 1.4 million pixels, and the number of pixels tends to increase.

  On the other hand, the number of pixels of the liquid crystal monitor provided in the electronic camera is often about 60,000 pixels to 100,000 pixels at most.

JP-A-4-354273

  Therefore, when using a liquid crystal monitor with a small number of pixels as a finder, it is not possible to check the focus state with the accuracy required for recording or print output. For this reason, images captured with an electronic camera are displayed on the computer screen. Or, there may be a case where the defocus is recognized only after printing with a printer.

  The present invention has been made in view of such circumstances, and the focus state of an image captured by a solid-state imaging device having a large number of pixels can be confirmed by an image display means having a small number of pixels. An object of the present invention is to provide an electronic camera that can be accurately aligned.

  In order to achieve the object, an electronic camera according to claim 1 forms image light indicating a subject on a light receiving surface of a solid-state image sensor, and outputs the image light imaged on the light-receiving surface of the solid-state image sensor as an image signal. Imaging means for converting into image, recording means for recording the image signal obtained by the imaging means, image display means for displaying an image having a smaller number of pixels than the number of pixels of the solid-state imaging device, and a manual focus adjustment member A manual focus function for focusing by operating and a magnification processing means for cutting out a predetermined partial image from all the captured images by the imaging means and displaying the clipped partial image on the screen of the image display means, And the enlargement processing means enlarges and displays the cut-out partial image on the screen of the image display means in response to a manual operation of the focus adjustment member. It is characterized in that.

  According to the first aspect of the invention, in response to manually operating the focus adjustment member, a predetermined partial image is cut out from all the captured images, and the cut out partial image is enlarged and displayed on the screen of the image display means. Therefore, it is possible to accurately check the focus state of the actually captured image. In addition, since the number of pixels of the entire captured image obtained from the imaging unit is larger than the number of pixels of the image display unit, the number of pixels required by the image display unit can be set even when the clipped partial image is enlarged and displayed. It can be obtained sufficiently.

  According to a second aspect of the present invention, in the electronic camera according to the first aspect, while the image display unit displays the partial image in an enlarged manner, a warning is given that the display on the image display unit is in the enlarged display mode. It has a warning means. As a result, it is possible to recognize whether the image displayed by the image display means is a whole captured image or a partial image cut out from the entire captured image.

  According to a third aspect of the present invention, in the electronic camera according to the second aspect, the warning unit causes the image display unit to display an icon indicating that the display on the image display unit is being enlarged. It is said.

  According to a fourth aspect of the present invention, in the electronic camera according to the third aspect, the icon is an icon indicating a magnifying glass.

  According to the present invention, in response to manually operating the focus adjustment member, a predetermined partial image is cut out from all the captured images, and the cut out partial image is enlarged and displayed on the screen of the image display means. The focus state of an image actually picked up by a solid-state image sensor with a large number of images can be confirmed with high accuracy by image display means with a small number of pixels, and manual focusing can be performed with high accuracy.

FIG. 1 is a block diagram showing an embodiment of an electronic camera according to the present invention. FIG. 2 is a perspective view showing a photographing state with the electronic camera shown in FIG. FIG. 3 is a view showing a display screen of the liquid crystal monitor of the electronic camera shown in FIG.

  A preferred embodiment of an electronic camera according to the present invention will be described in detail below with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing an embodiment of an electronic camera according to the present invention. This electronic camera is a digital camera that records a still image on a memory card 12 by operating a shutter release button 10 (see FIG. 2), and includes a liquid crystal monitor 14. The liquid crystal monitor 14 functions as an electronic viewfinder that can display a subject image during shooting, and functions as a monitor that displays a still image recorded in the memory card 12 during reproduction.

  When photographing with this digital camera (not only when recording a still image by fully pressing the release, but also when displaying a moving image on the liquid crystal monitor 14 when the release is half-pressed or when a movie is displayed), solid-state imaging is performed via the photographing lens 16. The subject image formed on the light receiving surface of the element (CCD) 18 is photoelectrically converted here and sequentially read out as a CCD signal and applied to the image signal processing circuit 20. Here, the CCD 18 having a larger number of pixels than the liquid crystal monitor 14 is used.

  The image signal processing circuit 20 includes a white balance adjustment circuit, a gamma correction circuit, and a YC processing circuit. The image data processed by these circuits is an image recording device 22, an autofocus device (AF device) 24, and a display range selection circuit. To 28. The image recording device 22 includes a compression circuit, a card interface, and the like. When the shutter release button 10 is operated, the YC signal (luminance signal Y and chroma signal C) is output from the YC processing circuit of the image signal processing circuit 20. The YC signal is received, and the compressed image data is recorded on the memory card 12 via the card interface.

  The AF device 24 becomes operable when the AF switch 26 is turned on, and performs contrast AF based on the luminance signal Y input from the image signal processing circuit 20. That is, the AF device 24 extracts a high frequency component of the luminance signal Y input from the image signal processing circuit 20, and obtains an evaluation value indicating the in-focus state of the photographing frame by integrating the high frequency component. Then, the photographing lens 16 is controlled so that the evaluation value becomes a maximum. The photographing lens 16 has a manual focus function, and when the AF switch 26 is turned off, it can be focused by manually operating a focus adjustment member such as a focus ring. It is like that.

  The display range selection circuit 28 normally outputs the image signal of the entire frame input from the image signal processing circuit 20 to the display circuit 30 as it is. On the other hand, when the enlargement switch 32 is turned on or the AF switch 26 is turned off. If it is, the operation becomes possible, and a predetermined partial image is cut out from the entire frame, and an image signal indicating the cut out partial image is output to the display circuit 30.

  The display circuit 30 displays an image on the entire screen of the liquid crystal monitor 14 based on the image signal input from the display range selection circuit 28. Therefore, when the release is half-pressed or during a movie, the subject image is displayed in real time or not in real time on the liquid crystal monitor 14 as a substantially continuous moving image. Can be decided.

  Next, when the image signal for the entire frame is output from the display range selection circuit 28, and when the partial image is cut out from the entire frame and the image signal indicating the cut out partial image is output. Will be described.

  Now, as shown in FIG. 2, when the subject 1 is photographed, the display range selection circuit 28 normally outputs the image signal for the entire frame to the display circuit 30 as described above. In this case, the number of pixels of the image signal input from the display range selection circuit 28 (the number of pixels of the CCD 18) is larger than the number of pixels of the liquid crystal monitor 14, so that the display circuit 30 matches the number of pixels of the liquid crystal monitor 14. The number of pixels in the horizontal direction and the vertical direction of the image signal input to is reduced (thinned out pixels at a predetermined rate) and output to the liquid crystal monitor 14.

  As a result, the liquid crystal monitor 14 displays an image of the entire frame being photographed as shown in FIG. On the other hand, when the enlargement switch 32 is turned on, the display range selection circuit 28 cuts out a partial image from the entire frame and outputs an image signal indicating the cut out partial image to the display circuit 30. In this case, since the number of pixels of the image signal of the partial image input from the display range selection circuit 28 is reduced, the display circuit 30 uses the image signal of the partial image to be input as it is or the pixel thinning rate is higher than in a normal case. The output is reduced to the liquid crystal monitor 14.

  As a result, the partial image cut out from the entire frame being photographed is enlarged and displayed on the liquid crystal monitor 14 as shown in FIG. Further, as shown in FIG. 5B, while the partial image is being enlarged and displayed, a warning is displayed that the display on the liquid crystal monitor 14 is being enlarged. In this embodiment, an icon 34 indicating a magnifying glass is displayed on the liquid crystal screen.

  As described above, when the enlargement switch 32 is turned on, the image displayed on the liquid crystal monitor 14 is enlarged and displayed, so that the focus state of the actually captured image can be accurately confirmed. Since the number of pixels of the CCD 18 is larger than the number of pixels of the liquid crystal monitor 14, the number of pixels required for the liquid crystal monitor 14 can be sufficiently obtained even when a partial image cut out from the entire frame is enlarged and displayed. .

  Further, in this embodiment, when the AF switch 26 is turned off and manual focusing is performed by manually operating the focus adjustment member, the enlargement switch 32 is turned on even if it is turned off. Similarly, the partial image is enlarged and displayed on the liquid crystal monitor 14. Thus, manual focusing can be performed with high accuracy while viewing the screen of the liquid crystal monitor displaying the partial image in an enlarged manner.

  As another embodiment of the present invention, a sensor such as a touch sensor for detecting whether or not the hand is touching the focus adjustment member of the photographing lens 16 is provided, and the hand touches the focus adjustment member by this sensor. During the detected period, the partial image may be enlarged and displayed on the liquid crystal monitor.

  Further, a macro switch for switching to macro shooting may be provided, and when switching to macro shooting by this macro switch, a partial image may be enlarged and displayed on the liquid crystal monitor.

  Further, a display switch for turning on / off the liquid crystal monitor may be provided, and when the macro switch is used to switch to the macro photography, the liquid crystal monitor is forcibly turned on, and the partial image is enlarged and displayed on the liquid crystal monitor. That is, when the LCD monitor is OFF, the optical viewfinder is used. However, since the parallax becomes large during macro photography, it is possible to force the LCD monitor to ON and focus while looking at the LCD monitor screen. it can.

  Furthermore, a touch panel for designating an enlargement area is provided on the screen of the liquid crystal monitor 14, and when the enlargement area is designated by the touch panel, a partial image corresponding to the designated enlargement area is cut out, and the cut out partial image is displayed on the liquid crystal monitor. May be enlarged and displayed. The autofocus device and the recording medium are not limited to those in this embodiment. In this embodiment, the digital camera has been described. However, the present invention is not limited to this, and the present invention is applicable to a video camera or the like as long as the number of pixels of the solid-state imaging device is larger than the number of pixels of the image display device. it can.

DESCRIPTION OF SYMBOLS 1 ... Subject, 10 ... Shutter release button, 12 ... Memory card, 14 ... Liquid crystal monitor 16 ... Shooting lens, 18 ... Solid-state image sensor (CCD), 20 ... Image signal processing circuit, 22 ... Image recording device, 24 ... Auto focus Device ... 26 AF switch 28 ... Display range selection circuit 30 ... Display circuit 32 ... Enlargement switch

Claims (4)

Imaging means for imaging image light indicating a subject on a light receiving surface of a solid-state image sensor, and converting the image light imaged on the light-receiving surface of the solid-state image sensor into an image signal;
Recording means for recording an image signal obtained by the imaging means;
Image display means for displaying an image having a smaller number of pixels than the number of pixels of the solid-state imaging device;
A manual focus function to focus by manually operating the focus adjustment member,
An enlargement processing unit that cuts out a predetermined partial image from all the captured images by the imaging unit and displays the cut-out partial image on the screen of the image display unit;
The electronic camera characterized in that the enlargement processing means enlarges and displays the cut-out partial image on the screen of the image display means in response to a manual operation of the focus adjustment member.   2. The electronic camera according to claim 1, further comprising warning means for warning that the display on the image display means is being enlarged while the image display means is displaying the partial image in an enlarged manner. .   3. The electronic camera according to claim 2, wherein the warning unit causes the image display unit to display an icon indicating that the display on the image display unit is being enlarged.   The electronic camera according to claim 3, wherein the icon is an icon indicating a magnifying glass.

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