Abstract:
A dual-lens assembly for an image photographing apparatus includes a board that performs a predetermined function in an image photographing apparatus. A first lens unit is joined with the board, and a second lens unit is joined with the board. The first and second lens units are oriented so that they obtain images in the same direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims the benefit under 35 U.S.C. § 119(a) of Korean Patent Application No. 2005-59218, filed on Jul. 1, 2005, the entire contents of which are hereby incorporated by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a dual-lens assembly having two independent lens modules for photographing moving images and still images, and an image photographing apparatus having the same.  
         [0004]     2. Description of the Related Art  
         [0005]     In general, a DSC (Digital Still Camera) converts an image that enters through a lens into a digital signal, and stores it in a recording medium such as a hard disk or a memory card. The photographed image is then stored in the recording medium, not on photographic film, and can be entered directly to a computer. Since a digital still camera is fully compatible with a computer, anyone with a personal computer can easily edit and modify a digital image (that is, a photograph). Also, the photographed image may be transmitted to an external computer system. However, due to the limited capacity of the recording medium, digital still cameras are mainly used for photographing still images. Although some digital still cameras are capable of recording moving images, their recording time is insufficient. Normally, recording moving (or video) images requires two separate processes: one for recording video images and another for recording and reproducing audio for the video images. Therefore, realistically, a digital still camera is inadequate for recording and reproducing video images with sound. For this reason, people prefer a camcorder, which is capable of recording or reproducing both video images of a subject being photographed and audio onto or from a recording medium such as a tape.  
         [0006]     Typically, a camcorder uses a cassette tape as its recording medium. The cassette tape is mounted in a deck for video recording. Also, a camcorder is typically provided with a microphone and a speaker. The camcorder, like the digital still camera, is capable of photographing a still image, but its picture quality is typically not as good as that of a digital still camera. Thus, the camcorder is used mostly for recording video images. Because a camcorder has more functions and thus a more complicated construction than a digital still camera, a typical camcorder is larger and more expensive than a digital still camera.  
         [0007]     Until recently, when people wanted to take advantage of both digital still cameras and camcorders, they had to purchase two separate products. This was a financial burden on users, and was also inconvenient because a user had to carry two separate products. To resolve this problem, there have been efforts to devise an apparatus for photographing a still image and recording a video image, that is, having functions of both a digital still camera and a camcorder built into a single product, so that a user can selectively choose which one to use according to the circumstances. A “dual cam” has been developed and sold as one such product.  
         [0008]     A dual cam has two lens modules with a different number of pixels. For instance, a lens module with a relatively higher number of pixels may be used for photographing a still image, whereas a lens module with a relatively lower number of pixels may be used for recording video images. Dual cam image photographing apparatuses capable of storing still images and moving (video) images photographed by each lens module in a medium such as a hard disk or a memory are now being actively developed.  
         [0009]     In the dual cam, however, incorporating two products into a single product has caused problems such as an increased product size and a more complicated structure. Therefore, recent research has focused on developing an image photographing apparatus having a simpler structure and a small size. Furthermore, research continues on improving manufacturing productivity.  
         [0010]     Accordingly, there is a need for a simpler, more compact image photographing apparatus capable of photographing both still images and moving (video) images.  
       SUMMARY OF THE INVENTION  
       [0011]     An aspect of the present invention is to address at least the above problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide a dual-lens assembly with an improved structure featuring a simple and easy arrangement of a plurality of lens modules, and an image photographing apparatus having the same.  
         [0012]     To achieve the above objects and advantages, a dual-lens assembly comprises a board performing a predetermined function in an image photographing apparatus, a first lens unit joined with the board, and a second lens unit joined with the board. The second lens unit is oriented so that it obtains an image in the same direction as the first lens unit.  
         [0013]     The first and second lens units may be arranged so that a virtual reference line connecting an optical axis passing through each of the lens units crosses a plane of the board.  
         [0014]     The reference line and the plane of the board may form an angle of about 40° to 50° with respect to one another.  
         [0015]     In an exemplary embodiment, the first lens unit may comprise a first lens module for photographing high quality picture images, a lens holder for encompassing the first lens module, and a first support bracket attached to the board for supporting the lens holder and the first lens module.  
         [0016]     In an exemplary embodiment, the second lens unit may comprise a second lens module for obtaining moving picture quality images and a second support bracket for supporting the second lens module to the board and the first lens unit.  
         [0017]     The second support bracket may comprise a first locking hole through which a screw is inserted into the second lens module, a second locking hole through which a screw is inserted into the lens holder, and a third locking hole through which a screw is inserted into the board.  
         [0018]     The first lens unit may be installed at a lower position than the second lens unit.  
         [0019]     The first lens unit may be arranged in a manner that the optical axis of the first lens unit is separated from the plane of the board.  
         [0020]     The optical axes of the first and second lens units may be separated from each other.  
         [0021]     The first and second lens units may be installed on opposite sides of the board and may be vertically offset with respect to one another.  
         [0022]     In accordance with another exemplary embodiment of the present invention, an image photographing apparatus comprises a main body, a board performing a predetermined function disposed in the main body, a first lens unit joined with the board, and a second lens unit joined with the board. The second lens unit is oriented so that it obtains an image in the same direction as the first lens unit.  
         [0023]     In accordance with still another exemplary embodiment of the present invention, an image photographing apparatus comprises a main body. A board is disposed in the main body, and the board has a plurality of electronic components for processing image data. A first lens unit is mounted on the board and has a first optical axis. The first lens unit obtains image data of a first quality and provides the image data to the plurality of electronic components. A second lens unit is mounted on the board and has a second optical axis. The second lens unit obtains image data of a second quality and provides the image data to the plurality of electronic components. The first and second optical axes are generally aligned so that the first and second lens units obtain images from the same direction. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]     The above and other objects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:  
         [0025]      FIG. 1  is a schematic front view of an image photographing apparatus according to an exemplary embodiment of the present invention;  
         [0026]      FIG. 2  is an exploded perspective view of the dual-lens assembly shown in  FIG. 1 ;  
         [0027]      FIG. 3  is a perspective view of the first lens unit of  FIG. 2 , assembled;  
         [0028]      FIG. 4  is a perspective view of the second lens unit of  FIG. 2 , assembled;  
         [0029]      FIG. 5  is a perspective view of the second lens unit joined with a board; and  
         [0030]      FIG. 6  is a perspective view of a dual-lens assembly (a first and a second lens unit) joined with a board. 
     
    
       [0031]     Throughout the drawings, the same reference numerals will be understood to refer to the same elements, features, and structures.  
       DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS  
       [0032]     The matters defined in the description such as a detailed construction and elements are provided to assist in a comprehensive understanding of the embodiments of the invention. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. Also, descriptions of well-known functions and constructions are omitted for clarity and conciseness.  
         [0033]     Referring to  FIGS. 1 and 2 , an image photographing apparatus according to an exemplary embodiment of the present invention includes an image photographing apparatus main body  10 , and a dual-lens assembly  100  installed in the main body  10 . The dual-lens assembly  100  includes a board  20 , and first and second lens units  30 ,  40  joined with the board  20 .  
         [0034]     A data storage medium (not shown) is installed in the main body  10 . Images (or image data) provided by each lens unit  30 ,  40  are stored in the storage medium. Also, a display panel  11  for displaying an image that enters through each lens unit  30 ,  40  is attached in an openable and closable manner to the outside of the main body  10 .  
         [0035]     The board  20  is electrically connected to both of the first and second lens units  30 ,  40  and controls the operation of each lens unit  30 ,  40  and processes photographed image data provided by the lens units  30 ,  40 . The board  20  has a substantially planar shape and is installed in the main body  10  in such a manner that its plane  21  stands basically upright. A plurality of electronic components are installed on the board  20 . Connectors  22 ,  23 ,  24  are provided on the board  20  and are connected to the first and second lens units  30 ,  40  and other functional components through a cable.  
         [0036]     In an exemplary embodiment, the first lens unit  30  is a digital still camera lens (DSC-lens) which may be used for photographing a still image. In particular, the first lens unit may be used for taking a high picture quality image by employing a CCD having a high number of pixels. The first lens unit  30  includes a first lens module  31 , a lens holder  33  for encompassing and supporting the lens module  31 , and a first support bracket  35  for attaching the lens holder  33  and the first lens module  31  to the board  20 .  
         [0037]     The first lens module  31  has a cylindrical shaped housing  31   a  in which a lens is installed. The lens holder  33  is fit into the outside of the housing  31   a  from the front side of the first lens module  31 . Meanwhile, the rear side of the first lens module  31  is combined to a CCD (Charge-Coupled Device) (not shown) and a CCD board. Moreover, on the rear side of the first lens module  31  there is a coupling part  31   b  having a locking hole  31   c  into which a screw is inserted. This coupling part  31   b  may be combined with the housing  31   a  as one unit, or screwed into the housing  31   a  as a separate component. Also, a drive motor  34  for driving the internal lens is installed at the outside of the first lens module  31 .  
         [0038]     The lens holder  33  has a pipe-shaped body  33   a  for encompassing the outside of the housing  31   a , and a first and a second screw coupling part  33   b ,  33   c  combined as one unit on the outside of the body  33   a . The first screw locking part  33   b  is formed to correspond to a locking hole  31   c  of the coupling part  31   b . Therefore, the first support bracket  35  and a screw  36  passing through the locking hole  31   c  are locked to a first screw coupling part  33   b , so that the first lens module  31 , the lens holder  33  and the first support bracket  35  may be locked together.  
         [0039]     The first support bracket  35  has a plurality of first screw holes  35   a  formed to correspond to the locking holes  31   c  for the screws  36 . Screws  37  pass through a plurality of second screw holes  35   b  to lock the first support bracket  35  to the board  20 . The portion of the first supporting bracket  35  where the second screw holes  35  are formed is bent so that it is substantially parallel with the board  20 . The first support bracket  35  is preferably made of metal.  
         [0040]     The first lens unit  30  having the above configuration is arranged so that an optical axis x 1  passing through the lens is spaced a distance away from the plane  21  of the board  20 . In the illustrated, exemplary embodiment of the present invention, the first lens unit  30  is located on the left side of the board  20  when seen from the front of the body  10  (that is, from the direction of a subject being photographed).  
         [0041]     The second lens unit  40  includes a second lens module  41 , and a second support bracket  43  for supporting the second lens module  41  to the board  20  and the first lens unit  30 .  
         [0042]     The second lens module  41  is used mainly for photographing moving images. That is, the second lens module produces images with a smaller number of pixels, yielding a poorer picture quality that that of the first lens module  31 . A lens  41   b  is installed in front of a housing  41   a , and another lens (not shown) is installed inside the housing  41   a.    
         [0043]     A locking boss  41   c  where a screw  45  is inserted is formed on one side of the housing  41   a , and a CCD board  44  for driving a CCD  42  is attached to the rear side of the housing  41   a . The CCD board  44  is provided with a connector  44   a  which joins the connector  22  on the board  20 .  
         [0044]     The second support bracket  43  has an “L” shape. In detail, it has a horizontal portion  43   a  and a vertical portion  43   b . The top end of the vertical portion  43   b  has a first locking hole H 1  through which a screw  45  is inserted into the locking boss  41   c  of the second lens module  41 . The horizontal portion  43   a  has a second locking hole H 2  through which a screw  46  is inserted into the board  20 , and a third locking hole H 3  through which a screw  48  is inserted into the second screw coupling part  33   c  of the lens holder  33 . In this manner, the second support bracket  43  combines with the second lens module  41 , the lens holder  33  and the board  20 , which in turn makes the first and second lens units  30 ,  40  firmly fastened to the board  20 .  
         [0045]     The second lens unit  40  having the above configuration is arranged in such a manner that an optical axis x 2  passing through the lens is spaced away from the plane  21  of the board  20  as well as the optical axis X 1 . In detail, the second lens unit  40  is located on the right side of the board  20 , on the opposite side of the board  20  than the first lens unit  30 . The second lens unit  40  is located above the first lens unit  30 . More specifically, the lens units  30 ,  40  are arranged so that a virtual reference line L 1  connecting the two axes X 1  and X 2  cross the plane  21  of the board  20 , that is, a reference plane A parallel to the plane  21  (see  FIG. 1 ), at a predetermined angle. In an exemplary embodiment, an angle θ between the reference line L and the reference plane A ranges from approximately 40° to 50°. The illustrated embodiment has an angle of approximately 45°.  
         [0046]     By installing the second lens unit  40  above the first lens unit  30  so that there is about a 45° angle between the reference line L and the reference plane A, the total width in a parallel direction of the reference plane A can be reduced. In other words, the image photographing apparatus can be manufactured in a smaller size. By the nature of the apparatus, the main body  10  tends to be cube-shaped. If the first and second lens units  30 ,  40  are arranged to at the corners of the main body  10  as in the exemplary embodiments of the invention, both the horizontal and vertical sizes of the main body  10  can be minimized while using the interior space of the main body  10  more efficiently.  
         [0047]     A method of assembling the image photographing apparatus according to an exemplary embodiment of the present invention will now be described. Initially, one of the first and second lens units  30 ,  40  is assembled. If the first lens unit  30  is assembled first, the lens holder  33  is inserted into the first lens module  31 . Then, the lens holder  33 , the first lens module  31 , and the first support bracket  35  (here, the first support bracket  35  is placed behind the first lens module  31 ) are combined with the screws  36 . In this manner, the assembly of the first lens unit  30  is finished as depicted in  FIG. 3 . Of course, before assembling the first support bracket  35 , the coupling part  31   b  and the CCD (not shown) are assembled behind the first lens module  31 .  
         [0048]     Next, the second lens unit  40 , the CCD  42  and the CCD board  44  are sequentially assembled to the second lens module  41 . Then, the second support bracket  43  is linked to the second lens module  41  using the screw  45 . In this manner, the assembly of the second lens unit  40  is finished as shown in  FIG. 4 .  
         [0049]     The completely assembled second lens unit  40  is joined with the board  20  by the screw  46 . That is, the screw  46  is inserted into the second locking hole H 2  of the second support bracket  43  to fasten the second lens unit  40  to the board  20 . The connector  44   a  of the CCD board  44  is joined with the connecter  22  of the board  20 . In this manner, the assembly of the second lens unit  40  to the board  20  is finished as illustrated in  FIG. 5 .  
         [0050]     The completely assembled first lens unit  30  is then joined with the board  20 . In detail, the screw  37  is inserted into the second screw hole  35   b  of the first support bracket  35  to fasten the first lens unit  30  to the board  20 . In this manner, the assembly of the first lens unit  30  to the board  20  is finished as illustrated in  FIG. 6 .  
         [0051]     In this state, the second support bracket  43  is joined with the lens holder  33  using the screw  48  to complete the assembly work of the dual-lens assembly  100 .  
         [0052]     Finally, the board  40  and the lens units  30 ,  40  are connected through a signal cable, so that signals and power can be transferred to each other.  
         [0053]     According to the exemplary embodiment of the dual-lens assembly and the image photographing apparatus of the present invention, the overall size of the set and the interior space of the apparatus can be reduced by arranging two lens units in an oblique direction crossing the reference plane of the board at an angle.  
         [0054]     Moreover, since the first and second lens units are all assembled to one board, the total number of components used can be reduced and the assembly time can be shortened. Accordingly, manufacturing productivity is enhanced and manufacturing costs can be reduced.  
         [0055]     While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.