Patent Publication Number: US-2010110267-A1

Title: Digital imaging apparatus and image display method

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
     This application is a divisional application of U.S. patent application Ser. No. 11/293,985, filed on Dec. 5, 2005, which claims the priority benefit of Japanese Patent Application No. 2004-355827, filed on Dec. 8, 2004, in the Japanese Patent Office, the disclosure of which is incorporated herein in its entirety by reference. 
    
    
     BACKGROUND 
     The present invention relates to a digital imaging apparatus and an image display method, and more particularly, to a digital imaging apparatus that can satisfactorily display different contents on at least two displays and an image display method. 
     Conventional high quality digital still cameras include status liquid crystal displays that display the status, such as an iris, a shutter speed, etc., of the cameras on the top of the camera body. Also, as described in Japanese Patent Laid-Open Publication No. 2004-180022, two displays, a main display disposed on one side of an enclosure part of a mobile phone and another display disposed on the rear side of the enclosure part, are controlled in accordance with an open/close state of the mobile phone. 
     Conventional digital still cameras display a photographed image on liquid crystal displays for monitors that are arranged on the back of the camera body. A disadvantage of such cameras is that a photographed image cannot be displayed or viewed from the status liquid crystal display on the top of the camera body. 
     Some conventional digital still cameras include mechanisms for rotating the viewing angle of a liquid crystal display disposed at the back of the camera body. However, such mechanisms result in increased manufacturing cost and introduce the risk of mechanical malfunction. 
     Relatively thin digital still cameras have a top which is slim and long, making it difficult to dispose a liquid crystal display on the top of the camera body. 
     SUMMARY 
     The present invention relates to a digital imaging apparatus with a plurality of displays that can display different content simultaneously. A display disposed on the top can be used for waist level photographing, and a display on the back can be used for eye level photographing. A variety of different modes is possible. Image content may be displayed on one of the displays while status information, such as photographing parameters or camera status, may be displayed on the other display. Different image content may be displayed on both displays simultaneously. For example, real-time video related to the photographing part of the camera may be displayed on one of the displays, while a recorded image may be displayed on the other display. Different recorded images may be displayed on the two displays simultaneously. 
     According to an embodiment of the invention, the display may be of different sizes. One display may have an aspect ratio of 4:3 and another may have an aspect ratio of 16:9. When operated in a wide mode, image content may be displayed on the 16:9 aspect ratio display; when operated in a normal mode, image content may be displayed on the 4:3 aspect ratio display. 
     According to an embodiment of the invention, a digital imaging apparatus may be provided with a display having an aspect ratio of 16:9. In one mode, image content may be displayed on the entire display in a wide format. In another mode, image content may be displayed on a central portion of the display in a 4:3 aspect ratio format. Informational content may be displayed on the portion of the display outside of the 4:3 aspect portion. 
     According to an embodiment of the invention, a digital imaging apparatus may be provided with at least two displays, where one display is disposed generally at the back of the apparatus and perpendicular to the optical axis, and the other display is disposed generally on the top of the apparatus and parallel to the optical axis. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features and advantages of the present invention will become more apparent from the following detailed description and the attached drawings in which: 
         FIG. 1  is a perspective view of a digital imaging apparatus according to an embodiment of the present invention; 
         FIG. 2  is a cross-sectional view of the digital imaging apparatus according to an embodiment of the present invention; 
         FIG. 3  is a block diagram of the digital imaging apparatus according to an embodiment of the present invention; 
         FIGS. 4A and 4B  are plane views of example content on various displays the digital imaging apparatus according to an embodiment of the present invention; 
         FIG. 5  is a detailed block diagram of the digital imaging apparatus according to an embodiment of the present invention; and 
         FIG. 6  is a cross-sectional view of a digital imaging apparatus according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The present invention will now be described more fully with reference to the accompanying drawings. 
       FIG. 1  is a perspective view of a digital imaging apparatus, such as a camera, obliquely from the rear according to an embodiment of the present invention.  FIG. 2  is a cross-sectional view of the camera shown in  FIG. 1 . 
     Referring to  FIGS. 1 and 2 , the digital camera comprises a camera body  100 , a zoom lens  1 , a focus lens  3 , a first display  15   a , a second display  15   b , a third display  15   c , a cross key  21   a , a zoom switch  21   b , and a shutter switch  21   c . The camera body  100  may be cube-shaped, or circular-shaped or other shapes. 
     The zoom lens  1  and the focus lens  3  form a photographing portion of the digital camera. An optical axis L of the zoom lens  1  and the focus lens  3  are parallel to each other as illustrated in  FIG. 2 , and generally perpendicular to the front and rear of the camera body  100 . 
     The rear of the camera body  100  comprises the first display  15   a , the third display  15   c , the cross key  21   a , and the zoom switch  21   b . The top of the camera body  100  comprises the second display  15   b  and the shutter switch  21   c.    
     The first display  15   a , the second display  15   b , and the third display  15   c  may be a liquid crystal display (LCD), an electro luminescence (EL) display, or a plasma display or other suitable display. According to an embodiment, the display screen of the first display  15   a  and the third display  15   c  may have a dimensional ratio of 4:3. According to an embodiment, the display screen of the second display  15   b  may have a dimensional ratio of 16:9. 
     Therefore, even if the camera body  100  is thin and has a slim and long top region, the second display  15   b  having a relatively wide screen can be arranged on the top region of the camera body  100 . The wide screen of the second display  15   b  can be more easily divided into a plurality of screens. 
     The first display  15   a  may display a monitor image. That is, the first display  15   a  has a relatively large screen and displays an image photographed by photographing portion. A user can photograph the image by viewing the display screen of the first display at for example, between about 20 to 50 cm from the rear of the camera body. 
     The first display  15   a  can also display information relating to the camera or photographing status which can be superimposed on an image as an screen display (OSD). The information indicating the photographing status may include an iris status, a shutter speed, status of a variety of modes, brightness of a subject, battery consumption, etc. The status of a variety of modes may include the display mode of each display, a recording mode of the photographed image, etc. The recording mode may be a 5 megapixel mode, a 3 megapixel mode, a 2 megapixel mode, or other resolution, and a video recording mode. The display mode may be the mode of display contents of the first display  15   a , the second display  15   b , and the third display  15   c . The display mode will be described later. 
     The third display  15   c  may function as an electronic view finder (EVF). That is, the third display  15   c  has the same function as an optical view finder and displays an image photographed by the photographing part. The user can photograph an image looking at the third display. The third display  15   c  the same size as the first display part  15   a  (a small image) and can display superimposed OSD information indicating the photographing status. 
     The second display  15   b  serves as the status display, displaying the photographing status and can display a monitor image. That is, the second display  15   b  simultaneously displays an image photographed and information indicating the photographing status. The second display  15   b  can display the photographed image with superimposed OSD information on the same display or the photographed image and the OSD information may be displayed on separate display regions. 
     Using the second display, the user can perform waist level photographing. To steady the camera to perform waist level photographing, the user can rest the camera body  100  on the user&#39;s stomach or can rest the user&#39;s elbow of their stomach while holding the camera. Also, the user can satisfactorily perform macro photographing through the second display part  15   b.    
     The digital camera according to the current embodiment displays the monitor image on the first display part  15   a , in order to perform the eye level photographing. Also, the digital camera can display the monitor image on the second display  15   b , to perform the waist level photographing. Furthermore, the digital camera does not need a mechanism for changing the position of a display screen, thereby reducing mechanical cost and risk of malfunction. 
       FIG. 3  is a block diagram of the digital camera according to an embodiment of the present invention. More specifically,  FIG. 3  illustrates the display control and display mode features of the digital camera. Like reference numerals in  FIGS. 1 ,  2 , and  3  denote like elements. The digital camera comprises a first CPU  19   a , a second CPU  19   b , and two memories  22   a  and  22   b , in addition to the elements illustrated in  FIGS. 1 and 2 . 
     The first CPU  19   a  controls the first display  15   a , the second display  15   b , and the third display  15   c  to display photographed images from the memory  22   a . Each of the images displayed on the first display  15   a , the second display  15   b , and the third display  15   c  is controlled by the first CPU  19   a . The first CPU  19   a  may select one, two or three of the first display  15   a , the second display  15   b  or the third display  15   c  to display a photographed image. 
     The first CPU  19   a  may superimpose OSD information including an iris, a shutter speed, etc. on a photographed image displayed on the first display  15   a  and the third display  15   c . Therefore, the first display  15   a  and the third display  15   c  can display the same image. When the third display  15   c  which is an Electronic View Finder (EVF) is not used, a user operates the cross key  21   a  and the first CPU  19   a  sets the first display  15   a  in a non-use state. In EVF photographing, a user operates the cross key  21   a  and the first CPU  19   a  sets the first display  15   a  in a non-use state. 
     The second CPU  19   b  may superimpose OSD information including the iris, the shutter speed, etc. on a photographed image displayed on the second display  15   b . The second CPU  19   b  may also control the second display  15   b  to display a photographed image and OSD information on separate display regions. Even though the first CPU  19   a  and the second CPU  19   b  may output the same or different OSD information, the OSD information may be displayed on different display regions. Therefore, the two CPUs are used to display different OSD information on the first and third displays  15   a  and  15   c , and the second display  15   b.    
     When the first CPU  19   a  selects one of the first display  15   a , the second display  15   b , and the third display  15   c  to display a photographed image, the first CPU  19   a  may control the other non-selected displays to displays OSD information only. In this regard, other non-selected displays may serve as a status display. When one of the first display  15   a , the second display  15   b , and the third display  15   c  serves as the status display, the first CPU  19   a  may reduce a backlight operating current of the first display  15   a , the second display  15   b , or the third display  15   c , thereby decreasing power consumption. 
     As illustrated in  FIG. 3 , the second CPU  19   b  may control the second display  15   b  to display OSD information on a separate region of the display. Also, the second CPU  19   b  may divide the second display  15   b  into three display regions lengthwise so that a center region c 1  can display the photographed image, and a left region c 2  and a right region c 3  can display OSD information. In this regard, the aspect ratio of the photographed image and the center region c 1  may be 4:3, such that the photographed image is displayed on one region of the display screen and the OSD information is clearly displayed on other regions. 
     The second CPU  19   b  may also divide the second display  15   b  into two display regions lengthwise so that a right region c 10  can display a photographed image, and a left region c 20  can display OSD information, and vice versa. 
     The display modes of the digital camera according to an embodiment will now be described with reference to  FIGS. 1 to 3 . 
     The digital camera includes a first mode where the first display  15   a  and the second display  15   b  simultaneously display the same photographed image, a second mode where one of the first display  15   a  and the second display  15   b  displays a photographed image, and a third mode where the first display  15   a  and the second display  15   b  simultaneously display different photographed images. The cross key  21   a  is a mechanism that may be used to select one of the three modes. That is, the first and second CPUs  19   a  and  19   b  perform the mode selected by the cross key  21   a.    
     In the first mode, the first CPU  19   a  controls the first display  15   a  and the second display  15   b  to simultaneously display the same photographed image. The photographed image may be a video or a still image. In the first mode, when it is difficult for the user to perform the waist level photographing through the second display  15   b  due to a subject&#39;s unexpected movement, the user may perform eye level photographing through the first display  15   a . Therefore, operation of the digital camera is flexible to handle a variety of photographing conditions and methods. 
     In the first mode, the first and second CPUs  19   a  and  19   b  control the first display  15   a  and the second display  15   b  to simultaneously display OSD information in addition to the same photographed image. As disclosed, according to an embodiment, the digital camera display a variety of information simultaneously. 
     In the third mode, the first and second CPUs  19   a  and  19   b  control one of the first and second display  15   a  and  15   b  to display the photographed image and display to display OSD information. In the non-selected particular, the first and second CPUs  19   a  and  19   b  control the first display  15   a  to display the photographed image when it is easier to see an image through the first display  15   a  and the second display  15   b  to display the camera status (OSD information) including the iris, the shutter speed, etc. According to an embodiment, the digital camera displays the photographed image and status information such that it is easy to see the image and check the status information. 
     In the third mode, the first and second CPUs  19   a  and  19   b  may control one of the first and second display  15   a  and  15   b  to display video and the other non-selected display to display a still image. For example, the first display  15   a  may display video obtained by a photographing operation, and the second display  15   b  may display a still image of the video at a certain time. Therefore, according to the embodiment, the digital camera can be used to check the photographing status of a subject via the still image displayed on one display, and a subject&#39;s movement or movement of a photographing direction via the video displayed on another display. 
     In the third mode, the first and second CPUs  19   a  and  19   b  may control one of the first and second display  15   a  and  15   b  to display video photographed by the photographing part and the other non-selected display to display an image recorded by the digital camera. For example, the first display  15   a  displays the video so the user can check the present photographing status, and simultaneously the second display  15   b  displays a past image (a still image or video) to check the past photographing status. Therefore, the digital camera according to an embodiment simultaneously displays the past and present photographing status. 
     When the digital camera starts to operate, the first and second CPUs  19   a  and  19   b  can control the first and second display  15   a  and  15   b  to display different images. In particular, the first display  15   a  may display an image obtained by the photographing part, and the second display  15   b  may display the OSD information, and vice versa. 
     The first and second CPUs  19   a  and  19   b  may also control the first and second displays  15   a  and  15   b  to display the same image. Various display modes may be selected by the cross key  21   a . The digital camera of the current embodiment displays the first, second, and third modes after a predetermined time elapses from the start to operate of the digital camera. For this, a user operates a function member like the cross key  21   a  and the CPUs  19   a ,  19   b , and  19   c  control the displays  15   a ,  15   b  and  15   c  according to that operation. 
     As can be seen, the digital camera of the invention can display various pieces of information in a variety of display modes using a plurality of displays after the digital camera is operated, thereby satisfactorily handling various shutter chances. 
       FIGS. 4A and 4B  are plane views of example display screens for the various displays of the digital camera according to an embodiment. Like reference numerals in  FIGS. 1 ,  2 ,  3 , and  4  denote like elements. 
     More specifically,  FIG. 4A  illustrates a display screen for the first display  15   a . The screen may be a conventional screen having an aspect ratio of 4:3. The screen may comprise 320 pixels across and 240 pixels down.  FIG. 4B  illustrates a display screen for the second display  15   b . The screen may be a wide screen having an aspect ratio of 16:9. The screen may 426 pixels across and 240 pixels down. 
     The display screen for by the second display  15   b  may be divided into a center display region c 1 , a left display region c 2 , and a right display region c 3 . The center display region c 1  is located in the center of the screen and may be formed of 320 pixels across and 240 pixels down. The left display region c 2  is located on the left of the screen and may be formed of 53 pixels across and 240 pixels down. The right display region c 3  is located on the right of the screen and may be formed of 53 pixels across and 240 pixels down. 
     The digital camera may operate in a normal mode in which a photographed image having the aspect ratio of 4:3 is displayed, and a wide mode in which a photographed image having the aspect ratio of 16:9 is displayed. The two modes are selected by operating the cross key  21   a . When the normal mode is selected when a user operates the cross key  21   a , the first CPU  19   a  may display an image in the normal mode (4:3 aspect) on the first display  15   a . When the wide mode is selected when a user operates using the cross key  21   a , the first CPU  19   a  may display an image in the wide mode (16:9 aspect) on the second display  15   b.    
     Therefore, according the digital camera may display an image in the normal mode on the first display  15   a  having the aspect ratio of 4:3; or may display an image in a wide mode, on the second display  15   b  having the aspect ratio of 16:9. 
     When the normal mode is selected using the cross key  21   a , the first CPU  19   a  controls the second display  15   b  to display the image in the normal mode on the center display region c 1  and the OSD information on the left and right display regions c 2  and c 3 . Therefore, in the normal mode, an image having the aspect ratio of 4:3 can be displayed on the center display region c 1  of the second display  15   b  having the aspect ratio of 16:9, and character information can be displayed on the left and right display regions c 2  and c 3 . Therefore, according to such an embodiment, the digital camera can display and without being partially covered by the character information. 
       FIG. 5  is a detailed block diagram of the digital camera according to an embodiment of the present invention. Like reference numerals in  FIGS. 1 ,  2 ,  3 ,  4 , and  5  denote like elements. 
     Referring to  FIG. 5 , the digital camera of the current embodiment comprises the zoom lens  1 , an iris  2 , the focus lens  3 , a charge-coupled device (CCD)  4 , a zoom motor  5 , an iris motor  6 , a focus motor  7 , a timing producer  8 , and a correlated double sampling (CDS) and automatic gain control (AGC) circuit  9 . The zoom lens  1 , the iris  2 , the focus lens  3 , and the CCD  4  are elements of a photographing part for photographing a subject. The iris motor  6  comprises an iris variant unit that varies an opening of the iris  2 . The timing producer  8  comprises a shutter speed variant unit that varies the shutter speed. The CDS and AGC circuit  9  forms a gain variant unit that varies the amplitude of the output of the CCD  4 . The iris motor  6 , the timing producer  8 , and the CDS and AGC circuit  9  are elements of an exposure variant part that varies the exposure of the photographing part. 
     The zoom lens  1  is moved by the zoom motor  5 . The iris motor  6  controls the opening of the iris  2 . The focus lens  3  is controlled by the focus motor  7 . Light from a subject is received through the zoom lens  1 , the iris  2 , and is focused by the focus lens  3  on a light receiving surface of the CCD  4 . 
     The CCD  4  photo-converts the subject light formed on the light receiving surface. The CCD  4  may be a complementary metal oxide semiconductor (CMOS) device or other digital image sensor. A color filter is arranged on the whole surface of the CCD  4 . The color filter may use three primary colors, red R, green G, and blue B, or use three complementary colors, cyan Cy, magenta Mg, and yellow Ye. The CCD  4  is operated by a timing signal produced by the timing producer  8 . 
     According to an embodiment, the digital camera comprises an A/D converter  10 , an image input controller  11 , an image signal processing circuit  12 , an image compression/expansion circuit  13 , a video encoder  14 , a first display  15   a , a second display  15   b , a third display  15   c , motor drivers  16 ,  17 , and  18 , a first CPU  19   a , a second CPU  19   b , an operating member  21 , memories  22   a  and  22   b , a video RAM (VRAM)  23 , a media controller  24 , and recording media  25 . The operating member  21  includes a power switch, a mode conversion dial, etc. in addition to the cross key  21   a , the zoom switch  21   b , and the shutter switch  21   c.    
     The first CPU  19   a  may control general operation of the digital camera according to an embodiment. The first CPU  19   a  controls an automatic exposure (AE) and an automatic focus (AF) based on setting conditions of the operating member  21  and outputs of the CCD  4 . 
     The operating member  21  provides an input signal to the first CPU  19   a . The first CPU  19   a  outputs a zoom operating signal for moving the zoom lens  1 , a focus operating signal for moving the focus lens  3 , an iris operating signal for opening/closing the iris  2 , and a gain control signal for controlling gain of the CDS and AGC circuit  9 . 
     An output signal of the CCD  4  is supplied to the A/D converter  10  from the CDS and AGC circuit  9 . The A/D converter  10  digitizes the image signal. An output signal of the A/D converter  10  supplied to the image input controller  11  and stored in the memory  22   a.    
     The output signal of the CCD  4  is digitized by the A/D converter  10  from the CDS and AGC circuit  9  and then supplied to the image signal processing circuit  12 . The image signal processing circuit  12  performs image processing such as gamma correction, edge emphasis, white balance, etc. The video encoder  14  produces a component color video signal, which is supplied to the VRAM  23 . The color video signal is supplied to each of the first, second, and third displays  15   a ,  15   b , and  15   c , or to one or two of them to display a monitor image which is being photographed. 
     Also, the first CPU  19   a  controls the image signal processing circuit  12  to superimpose OSD information including the iris, the shutter speed, etc. on the photographed image, such that the superimposed image can be displayed on the first and third display part  15   a  and  15   c . The second CPU  19   b  controls the second displays  15   b  to display OSD information and the photographed image. 
     The image signal corresponding to a screen stored in the memory  22   a  is processed in the image signal processing circuit  12  and is provided to the image compression/expansion circuit  13 . The image compression/expansion circuit  13  compression-encodes image data. The image data, not necessarily restricted thereto, may be compressed according to Joint Photographic Experts Group (JPEG) standards for image compression based on a discrete cosine transform (DCT). 
     The compression-encoded image signal is provided to the recording media  25  via the media controller  24  and is recorded on the recording media  25 . The recording media  25  may be an attachable/detachable card type memory using a flash memory. The recording media  25  may be comprised of a nonvolatile memory, a magnetic tape, a magnetic disk, an optical disk embedded in the digital camera. 
     An image file of the recording media  25  is open when it is reproduced and the image data is read. The image data read from the recording media  25  is supplied to the image compression/expansion circuit  13 . The image compression/expansion circuit  13  expands the image signal. An output of the image compression/expansion circuit  13  is supplied to the video encoder  14 . An output signal of the video encoder  14  is supplied to one of, two of, or all of, the first, second, and third displays  15   a ,  15   b , and  15   c , to display a reproduced image. 
       FIG. 6  is a cross-sectional view of a digital camera according to another embodiment of the present invention. Like reference numerals in  FIGS. 1 ,  2 ,  3 ,  4 ,  5 , and  6  denote like elements. The digital camera illustrated in  FIG. 6  has a first display  15   a  and a second display  15   b  which have a modified view angle from a conventional display. 
     As is known be one of skill in the art, conventional display panels have a limited viewing angle. In other words, when a conventional display is viewed directly, the quality of the image is the best, with all of the detail clearly visible and in the appropriate colors. However, when viewed from an angle toward the side, the image quality may be degraded or appear black, or the colors are modified from the true colors. This phenomenon is characteristic of many different display technologies, especially LCD displays. 
     A first display  15   a  is disposed at the rear of the camera body  100  generally perpendicular to the optical axis L of the zoom lens  1  and the focus lens  3 . A second display  15   b  is arranged on the top of the camera body  100  generally parallel to the optical axis L. 
     In accordance with this embodiment of the invention, the first display  15   a  is not a conventional display, but a display that has a modified view angle B 1  that preferably extends much higher and toward the top of the camera than a conventional display so that the display is more readily viewable if the camera is held at a wait-level position. Similarly, display  15   b , which is disposed on the top of the camera, also has a modified view angle B 2  that preferably extends much lower and toward the back of the camera so that the display  15   b  is more readily viewable if the camera is held in a position between waist-level and eye-level. As illustrated in  FIG. 6 , there is an overlap of the view angle B 1  for the display  15   a  disposed on the back of the camera and the view angle B 2  for the display  15   b  disposed on the top of the camera. In addition, the combination of the view angle B 1  and the view angle B 2  provide a combined viewing angle that extends beyond 90 degrees. In this regard, using the combination of the two displays  15   a  and  15   b , a user can enjoy a continuous and extremely large combined viewing angle, extending from the forward-most angle of B 2  and through to the lower-most angle of B 1 . Thus, a user can readily, easily and continuously view display information extending from eye-level photographing to waist-level photographing, and any position between. 
     The present invention is not restricted to a digital camera but can readily be applied to a video camera, a film camera, or other imaging device. 
     A plurality of displays can display the same or different contents, thereby satisfactorily handling various photographing status and methods. 
     The two displays accommodate photographing at both the eye level and the waist level. Therefore, the present invention can display photographing status and a photographed image on the top of the camera body. The present invention prevents hand tremble caused by the waist level photographing, performs macro photographing, and the eye level photographing. The present invention does not require mechanical movement of the displays, thereby reducing the risk of mechanical malfunction. 
     Each of the plurality of displays can display the same or different contents when the digital camera is operated. 
     A view angle of each of the plurality of displays is established according to the location of each of the plurality of displays of the digital camera. 
     While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.