Abstract:
An image display apparatus according to an embodiment includes a recording medium on which a composite image obtained by composing a plurality of images corresponding to respective parallaxes is printed by a print apparatus, a lenticular lens having a plurality of cylindrical lenses arranged side by side, and configured to display the composed image separately for each direction of parallax, and a position adjustment mechanism configured to adjust relative position of the recording medium and the lenticular lens, and the position adjustment mechanism includes an inclination adjustment unit capable of changing an inclination angle of at least one of the recording medium and the lenticular lens, and a horizontal adjustment unit capable of moving at least one of the recording medium and the lenticular lens in a substantially perpendicular direction to a border line of the cylindrical lens, and the inclination adjustment unit and the horizontal adjustment unit can make adjustment independently, and a rotation center of the inclination adjustment unit is provided at a portion of the horizontal adjustment unit, and the inclination angle can be changed on the basis of the rotation center which is a reference.

Description:
FIELD 
       [0001]    Embodiments of the present invention relate to an image display apparatus. 
       BACKGROUND 
       [0002]    There is a conventional image display apparatus that displays an image which appears to be differently depending on the direction a person sees the image, so that the image appears to be stereoscopic, and for example, in order to display parallax images which are shown in multiple directions and which can be seen in multiple directions, a composite image obtained by composing parallax images is recorded onto a recording medium such as a sheet by means of printing, and the image is displayed through a lenticular lens. The composite image is made by arranging multiple parallax images in a rectangular form, and the same parallax image is displayed in the same direction by many cylindrical lenses constituting the lenticular lens. 
         [0003]    In this case, when the position of the composite image printed on the recording medium does not match the position of the lenticular lens, the image displayed is corrupted in a conventional image display apparatus. In the conventional image display apparatus, the positional deviation includes horizontal positional deviation and inclination deviation, but it is difficult to independently adjust both of them, and it has not been easy to adjust the positions. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  is a configuration diagram illustrating an image display apparatus according to a first embodiment. 
           [0005]      FIGS. 2(   a ) and  2 ( b ) are transverse sectional views illustrating the image display apparatus according to the first embodiment. 
           [0006]      FIG. 3  is a longitudinal sectional view illustrating a lenticular lens unit of the image display apparatus according to the first embodiment. 
           [0007]      FIGS. 4(   a ) to  4 ( c ) are figures illustrating a method for forming a recording medium for the image display apparatus according to the first embodiment. 
           [0008]      FIG. 5  is a first flowchart illustrating a method for assembling the image display apparatus according to the first embodiment. 
           [0009]      FIG. 6  is a second flowchart illustrating a method for assembling the image display apparatus according to the first embodiment. 
           [0010]      FIG. 7  is a longitudinal sectional view illustrating an image display apparatus according to a second embodiment. 
           [0011]      FIG. 8  is a longitudinal sectional view illustrating an image display apparatus according to a third embodiment. 
           [0012]      FIG. 9  is a longitudinal sectional view illustrating an image display apparatus according to a fourth embodiment. 
           [0013]      FIG. 10  is a longitudinal sectional view illustrating an image display apparatus according to a fifth embodiment. 
           [0014]      FIG. 11  is a longitudinal sectional view illustrating an image display apparatus according to a sixth embodiment. 
           [0015]      FIG. 12  is a longitudinal sectional view illustrating an image display apparatus according to a seventh embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    Embodiments will be hereinafter explained with reference to drawings. 
       First Embodiment 
       [0017]    An image display apparatus according to a first embodiment will be hereinafter explained with reference to drawings. 
         [0018]    First, overview of the image display apparatus of the first embodiment will be explained with reference to  FIG. 1 .  FIG. 1  is a configuration diagram illustrating the image display apparatus according to the first embodiment. 
         [0019]    As shown in  FIG. 1 , a recording medium  1  is formed with a recorded image  2 , and, for example, the recording medium  1  is attached to a medium attachment unit  3  which is a flat plate. A lenticular lens unit  4  is attached so that it is in contact with the recording medium  1  attached to the medium attachment unit  3 . 
         [0020]    The image display apparatus according to the first embodiment before and after the assembly will be explained with reference to  FIG. 2 .  FIG. 2  is a transverse sectional view illustrating the image display apparatus according to the first embodiment. 
         [0021]      FIG. 2(   a ) schematically illustrates the image display apparatus according to the first embodiment before the assembly, and as shown in  FIG. 2(   a ), the recording medium  1  is formed with the recorded image  2 , and the recording medium  1  is attached to the medium attachment unit  3 , and thereafter, the lenticular lens unit  4  is attached to the recording medium  1 . 
         [0022]    Therefore, while a lenticular lens  5  is brought into contact with the recorded image  2 , a position adjustment mechanism  6  is adjusted. In this case, the lenticular lens  5  is configured in such a manner that many inverted U-shaped cylindrical lenses  14  are arranged side by side. In  FIGS. 2(   a ),  2 ( b ), the vertical direction of the drawings is a direction substantially in parallel with the border lines between the cylindrical lenses  14 , like the subsequent drawings. In  FIGS. 2(   a ),  2 ( b ), the horizontal direction of the drawings is a direction substantially perpendicular to the border lines between the cylindrical lenses  14 , like the subsequent drawings 
         [0023]    The position of the recording medium  1  is somewhat determined by a medium abutment surface  7 , but antislip processing is applied to the medium attachment surface of the medium attachment unit  3 , or a antislip sheet is pasted to the medium attachment surface of the medium attachment unit  3 , whereby it is made into an antislip surface  8 , so that the recording medium  1  does not move together with the lenticular lens  5  when the lenticular lens  5  moves on the recording medium  1 . 
         [0024]      FIG. 2(   b ) schematically illustrates the image display apparatus according to the first embodiment after the assembly, and as shown in  FIG. 2(   b ), the medium attachment unit  3  and the lenticular lens unit  4  are fixed with screws or hooks, not shown, so as to maintain such state as to press the lenticular lens  5  and the recorded image  2  having been adjusted. 
         [0025]    In this case, the lenticular lens unit  4  has the position adjustment mechanism  6 .  FIG. 3  is a longitudinal sectional view illustrating a lenticular lens unit of the image display apparatus according to the first embodiment. 
         [0026]    As shown in  FIG. 3 , the lenticular lens  5  is connected via a rotation center screw  11  with a slide mechanism  10  provided at an upper portion of  FIG. 3  with respect to a frame  9 . 
         [0027]    In this case, horizontal adjustment knobs  12  (hereinafter referred to as a horizontal adjustment unit) are provided to connect with the slide mechanism  10 , and for example, in a case where the slide mechanism  10  is of a direct-acting method, a user grabs one of or both of the knobs and moves the knobs in a horizontal direction (which will hereinafter refer to a direction substantially perpendicular to the border lines of the cylindrical lens  14  constituting the lenticular lens  5 ), so that the slide mechanism  10  connected with the lenticular lens  5  can be adjusted in the horizontal direction of  FIG. 3 . In a case where the slide mechanism  10  is of a feed screw method, a user rotates one of or both of the knobs, so that the slide mechanism  10  connected with the lenticular lens  5  can be adjusted in the horizontal direction of  FIG. 3 . In a case where the horizontal adjustment knobs  12  are of a screw method, the position in the horizontal direction is less likely to deviate from the adjusted state because of the friction of the screw even if the user releases his or her hand from the horizontal adjustment knobs  12  after the adjustment. 
         [0028]    Further, inclination adjustment knobs  13  (which will be hereinafter also referred to as an inclination adjustment unit) are provided to be in contact with a component connected with the rotation center screw  11  of the slide mechanism  10 , and for example, in a case where the inclination adjustment knobs  13  are a direct-acting method, a user grabs one of or both of the knobs of the inclination adjustment knobs  13  at the right and the left and moves the knobs in the vertical direction (which will hereinafter refer to a direction substantially in parallel with the border lines of the cylindrical lens  14  constituting the lenticular lens), and pushes or pulls the contact portions at the right and the left of the inclination adjustment knobs  13 , so that the user can adjust the inclination of the component connected with the rotation center screw  11  of the slide mechanism  10  connected with the lenticular lens  5  with respect to the rotation center screw  11  serving as the center of rotation. In a case where the inclination adjustment knobs  13  are of a feed screw method, a user rotates one of or both of the knobs of the inclination adjustment knobs  13 , and pushes or pulls the contact portions at the right and the left of the inclination adjustment knobs  13 , so that the user can adjust the inclination of the component connected with the rotation center screw  11  of the slide mechanism  10  connected with the lenticular lens  5  with respect to the rotation center screw  11  serving as the center of rotation. When the inclination adjustment knobs  13  are of a screw method, the inclination is less likely to deviate from the adjusted state because of the friction of the screw even if the user releases his or her hand from the inclination adjustment knobs  13  after the adjustment. 
         [0029]    In this case, the position adjustment mechanism  6  of the image display apparatus according to the first embodiment refers to the horizontal adjustment knobs  12  and the inclination adjustment knobs  13 . 
         [0030]    Therefore, in the image display apparatus according to the first embodiment, when the horizontal adjustment knobs  12  and the inclination adjustment knobs  13  are adjusted, the lenticular lens  5  can be independently adjusted in the horizontal direction and in the inclination direction of  FIG. 3  with respect to the frame  9 . Since the horizontal adjustment knobs  12  and the inclination adjustment knob  13  are arranged in proximity to each other, the horizontal adjustment knobs  12  and the inclination adjustment knobs  13  can be easily adjusted at a time. 
         [0031]    On the other hand, the recorded image  2  is formed by printing of a print apparatus.  FIGS. 4(   a ) to  4 ( c ) are figures illustrating a method for forming a recording medium of the image display apparatus according to the first embodiment. 
         [0032]    As shown in  FIG. 4(   a ), for example, while a recording medium  22  which is a recording sheet such as paper is conveyed in a conveying direction  23  in a printer main body  21 , and a print apparatus uses a printer head  24  to print the recorded image  25  of a composite image made by composing multiple images parallaxes. As shown in  FIG. 4(   b ), the recorded image  25  is formed on the printed recording medium  22 . 
         [0033]    Further, as shown in  FIG. 4(   c ), this recording medium  22  is attached to a medium attachment unit  26 . In this case, as an indication of the position where the recording medium  22  is attached to the medium attachment unit  26 , a medium abutment surfaces  27  are provided on three sides of four external peripheral sides of the medium attachment unit  26 , and the external periphery of the recording medium  22  is brought into abutment with the medium abutment surfaces  27 , so that the recording medium  22  can be easily positioned with respect to the medium attachment unit  26 . 
         [0034]    Subsequently, a method for producing the image display apparatus according to the first embodiment will be explained with reference to  FIGS. 5 ,  6 .  FIG. 5  is a first flowchart illustrating a method for assembling the image display apparatus according to the first embodiment.  FIG. 6  is a second flowchart illustrating a method for assembling the image display apparatus according to the first embodiment. 
         [0035]    In this case, as shown in  FIG. 5 , first, the recorded image is printed on the recording medium  22  (step S 1 ). Subsequently, the recording medium  22  having the recorded image  25  printed thereon is attached to the medium attachment unit  26  (step S 2 ). Further, the lenticular lens unit  4  is attached to the medium attachment unit  26  attached to the recording medium  22  (step S 3 ). While a user sees the recorded image  2  through the lenticular lens  5 , the user adjusts the inclination adjustment knobs  13  of the position adjustment mechanism  6  of the lenticular lens unit  5  (step S 4 ). 
         [0036]    In this case, if the inclination of the recorded image  2  seen through the lenticular lens  5  is correct (YES in step S 5 ), the user adjusts the horizontal adjustment knobs  12  of the position adjustment mechanism  6  of the lenticular lens unit  4  while the user sees the recorded image  2  through the lenticular lens  5  (step S 6 ). If the inclination of the recorded image  2  seen through the lenticular lens  5  is not correct (NO in step S 5 ), step S 4  is performed again so that the user adjust the inclination adjustment knobs  13  again. 
         [0037]    Further, if the horizontal position of the recorded image  2  seen through the lenticular lens  5  is correct (YES in step S 7 ), the processing is terminated. When the horizontal position of the recorded image  2  seen through the lenticular lens  5  is not correct (NO in step S 7 ), step S 6  is performed again, and the user adjusts the horizontal adjustment knobs  12  again. 
         [0038]      FIG. 5  shows the procedure for adjusting the inclination adjustment knobs  13  first then adjusting the horizontal adjustment knobs  12 , but the embodiment is not limited to this procedure. For example, in the procedure, the horizontal adjustment knobs  12  may be adjusted first, and then the inclination adjustment knob  13  may be adjusted. 
         [0039]    As shown in  FIG. 6 , first, the recorded image  25  is printed on the recording medium  22  (step S 11 ). Subsequently, the recording medium  22  having the recorded image  25  printed thereon is attached to the medium attachment unit  26  (step S 21 ). Further, the lenticular lens unit  4  is attached to the medium attachment unit  26  attached to the recording medium  22  (step S 13 ). While the user sees the recorded image  2  through the lenticular lens  5 , the user adjusts the inclination adjustment knobs  13  of the position adjustment mechanism  6  of the lenticular lens unit  5  (step S 14 ). 
         [0040]    In this case, if the inclination of the recorded image  2  seen through the lenticular lens  5  is correct (YES in step S 15 ), the user adjusts the horizontal adjustment knobs  12  of the position adjustment mechanism  6  of the lenticular lens unit  4  while the user sees the recorded image  2  through the lenticular lens  5  (step S 16 ). 
         [0041]    Further, if the horizontal position of the recorded image  2  seen through the lenticular lens  5  is correct (YES in step S 17 ), the user checks whether the inclination of the recorded image  2  through the lenticular lens  5  is correct or not (step S 18 ). 
         [0042]    If the horizontal position of the recorded image  2  seen through the lenticular lens  5  is not correct (NO in step S 17 ), step S 16  is performed again, and the user adjusts the horizontal adjustment knobs  12  again. 
         [0043]    In this case, if the inclination of the recorded image  2  seen through the lenticular lens  5  is correct (YES in step S 18 ), the processing is terminated. 
         [0044]    If the inclination of the recorded image  2  seen through the lenticular lens  5  is not correct (NO in step S 18 ), this means that the inclination in the recorded image  2  is deviated, which was once correctly adjusted while the horizontal adjustment knobs  12  were adjusted, and therefore, step S 14  is performed again, and the inclination adjustment knobs  13  are adjusted again and the horizontal adjustment knobs  12  are adjusted again (step S 14  to step S 18 ). 
         [0045]    Therefore, according to the flowchart of  FIG. 6 , whether the inclination adjustment knobs  13  are correct or not is checked again, and therefore, more accurately positioned adjustment state can be attained as compared with the flowchart of  FIG. 5 . 
         [0046]    Like  FIG. 5 ,  FIG. 6  shows the procedure for adjusting the inclination adjustment knobs  13  first and the adjusting the horizontal adjustment knobs  12 , but the procedure is not limited thereto. For example, in the procedure, the horizontal adjustment knobs  12  may be adjusted first, and then the inclination adjustment knob  13  may be adjusted. 
         [0047]    As described above, according to the image display apparatus of the first embodiment, the user can easily adjust the position of the lenticular lens  5  while the user sees the displayed recorded image  2  with the recorded image of the recording medium  1 . 
       Second Embodiment 
       [0048]    An image display apparatus according to a second embodiment will be hereinafter explained with reference to  FIG. 7 . The second embodiment is different from the first embodiment only in a lenticular lens unit  31 , and the second embodiment is the same as the first embodiment except the description of the lenticular lens unit  31 , and therefore, the same portions are denoted with the same reference numerals, and detailed explanation thereabout is omitted.  FIG. 7  is a longitudinal sectional view illustrating a lenticular lens unit of the image display apparatus according to the second embodiment. 
         [0049]    As shown in  FIG. 7 , a lenticular lens  5  is connected via a rotation center screw  11  with a slide mechanism  10  provided at a lower portion of  FIG. 7  with respect to a frame  9 . The lenticular lens  5  is configured in such a manner that many inverted U-shaped cylindrical lenses  14  are arranged side by side. Further, horizontal adjustment knobs  12  are provided to connect with the slide mechanism  10 , and for example, in a case where the slide mechanism  10  is of a direct-acting method, a user grabs one of or both of the horizontal adjustment knobs  12  and moves the knobs in a horizontal direction, so that the slide mechanism  10  connected with the lenticular lens  5  can be adjusted in the horizontal direction of  FIG. 7 . In a case where the slide mechanism  10  is of a feed screw method, a user rotates one of or both of the horizontal adjustment knobs  12 , so that the slide mechanism  10  connected with the lenticular lens  5  can be adjusted in the horizontal direction of  FIG. 7 . In a case where the horizontal adjustment knobs  12  are of a screw method, the position in the horizontal direction is less likely to deviate from the adjusted state because of the friction of the screw even if the user releases his or her hand from the horizontal adjustment knobs  12  after the adjustment of the horizontal adjustment knobs  12 . 
         [0050]    Further, inclination adjustment knobs  13  are provided to be in contact with a component connected with the rotation center screw  11  of the slide mechanism  10 , for example, in a case where the inclination adjustment knobs  13  are a direct-acting method, a user grabs one of or both of the knobs of the inclination adjustment knobs  13  at the right and the left and moves the knobs in the vertical direction, and pushes or pulls the contact portions at the right and the left of the inclination adjustment knobs  13 , so that the user can adjust the inclination of the component connected with the rotation center screw  11  of the slide mechanism  10  connected with the lenticular lens  5  with respect to the rotation center screw  11  serving as the center of rotation. In a case where the inclination adjustment knobs  13  are of a feed screw method, a user rotates one of or both of the knobs of the inclination adjustment knobs  13 , and pushes or pulls the contact portions at the right and the left of the inclination adjustment knobs  13 , so that the user can adjust the inclination of the component connected with the rotation center screw  11  of the slide mechanism  10  connected with the lenticular lens  5  with respect to the rotation center screw  11  serving as the center of rotation. When the inclination adjustment knobs  13  are of a screw method, the inclination is less likely to deviate from the adjusted state because of the friction of the screw even if the user releases his or her hand from the inclination adjustment knobs  13  after the adjustment of the inclination adjustment knobs  13 . 
         [0051]    In this case, the position adjustment mechanism of the image display apparatus according to the second embodiment refers to the horizontal adjustment knobs  12  and the inclination adjustment knobs  13 . 
         [0052]    Therefore, in the image display apparatus according to the second embodiment, like the first embodiment, when the horizontal adjustment knobs  12  and the inclination adjustment knobs  13  are adjusted, the lenticular lens  5  can be independently adjusted in the horizontal direction and in the inclination direction of  FIG. 7  with respect to the frame  9 . Since the horizontal adjustment knobs  12  and the inclination adjustment knob  13  are arranged in proximity to each other, the horizontal adjustment knobs  12  and the inclination adjustment knobs  13  can be easily adjusted at a time. 
       Third Embodiment 
       [0053]    An image display apparatus according to a third embodiment will be hereinafter explained with reference to  FIG. 8 . The third embodiment is different from the first embodiment only in a lenticular lens unit  41  and inclination adjustment knobs  42 , and the third embodiment is the same as the first embodiment except the description of the lenticular lens unit  41  and the inclination adjustment knobs  42 , and therefore, the same portions are denoted with the same reference numerals, and detailed explanation thereabout is omitted.  FIG. 8  is a longitudinal sectional view illustrating a lenticular lens unit of the image display apparatus according to the third embodiment. 
         [0054]    As shown in  FIG. 8 , a lenticular lens  5  is connected via a rotation center screw  11  with a slide mechanism  10  provided at a lower portion of  FIG. 8  with respect to a frame  9 . The lenticular lens  5  is configured in such a manner that many inverted U-shaped cylindrical lenses  14  are arranged side by side. Further, horizontal adjustment knobs  12  are provided to connect with the slide mechanism  10  at the lower portion of  FIG. 8 , and for example, in a case where the slide mechanism  10  is of a direct-acting method, a user grabs one of or both of the horizontal adjustment knobs  12  and moves the horizontal adjustment knobs  12  in a horizontal direction, so that the slide mechanism  10  connected with the lenticular lens  5  can be adjusted in the horizontal direction of  FIG. 8 . In a case where the slide mechanism  10  is of a feed screw method, a user rotates one of or both of the horizontal adjustment knobs  12 , so that the slide mechanism  10  connected with the lenticular lens  5  can be adjusted in the horizontal direction of  FIG. 8 . In a case where the horizontal adjustment knobs  12  are of a screw method, the position in the horizontal direction is less likely to deviate from the adjusted state because of the friction of the screw even if the user releases his or her hand from the inclination adjustment knob  13  after the adjustment of the inclination adjustment knob  13 . 
         [0055]    However, inclination adjustment knobs  42  are provided to be in contact with the lenticular lens  5  at the upper portion of  FIG. 8 , and where the user grabs one of or both of the knobs of the inclination adjustment knobs  42  at the upper and lower sides and moves the knobs in the vertical direction, so that the user can adjust the inclination of the component connected with the rotation center screw  11  of the slide mechanism  10  connected with the lenticular lens  5  with respect to the rotation center screw  11  serving as the center of rotation, and can adjust the lenticular lens  5  in the inclination direction of  FIG. 8 . In order to prevent deviation from the adjusted state after the inclination has been adjusted with the inclination adjustment knobs  42  in the image display apparatus according to the third embodiment, the rotation center screw  11  may be loosened while the inclination is adjusted with the inclination adjustment knobs  42 , and the rotation center screw  11  may be tightened after the inclination has been adjusted. In this case, the position adjustment mechanism of the image display apparatus according to the third embodiment refers to the horizontal adjustment knobs  12  and the inclination adjustment knobs  42 . 
         [0056]    Therefore, in the image display apparatus according to the third embodiment, when the horizontal adjustment knobs  12  and the inclination adjustment knobs  42  are adjusted, the lenticular lens  5  can be independently adjusted in the horizontal direction and in the inclination direction of  FIG. 8  with respect to the frame  9 . 
         [0057]    Further, in the image display apparatus according to the third embodiment, the lenticular lens  5  including the inclination adjustment knobs  42  can be inclined, and therefore, this allows the user to make adjustment in a more intuitive manner. 
       Fourth Embodiment 
       [0058]    An image display apparatus according to the fourth embodiment will be hereinafter explained with reference to  FIG. 9 . The fourth embodiment is different from the first embodiment only in a lenticular lens unit  51  and horizontal and inclination adjustment knobs  52 , and the fourth embodiment is the same as the first embodiment except the description of the lenticular lens unit  51  and the horizontal and inclination adjustment knobs  52 , and therefore, the same portions are denoted with the same reference numerals, and detailed explanation thereabout is omitted.  FIG. 9  is a longitudinal sectional view illustrating a lenticular lens unit of the image display apparatus according to the fourth embodiment. 
         [0059]    As shown in  FIG. 9 , a lenticular lens  5  is connected via a rotation center screw  11  with a slide mechanism  10  provided at a lower portion of  FIG. 9  with respect to a frame  9 . The lenticular lens  5  is configured in such a manner that many inverted U-shaped cylindrical lenses  14  are arranged side by side. 
         [0060]    However, the horizontal adjustment knobs  12  and the inclination adjustment knobs  13 ,  42  are not separately provided, and instead, the horizontal and inclination adjustment knob  52  is provided. The horizontal and inclination adjustment knob  52  has such structure that the horizontal adjustment knob  12  and the inclination adjustment knobs  13 ,  42  are integrated. 
         [0061]    In this case, the horizontal and inclination adjustment knobs  52  are provided to connect with a component connected with the rotation center screw  11  and the slide mechanism  10 , and, for example, in a case where the slide mechanism  10  is of a direct-acting method, a user grabs one of or both of the knobs of the horizontal and inclination adjustment knobs  52  and moves the knobs in the horizontal direction, so that the user can adjust the slide mechanism  10  connected with the lenticular lens  5  in the horizontal direction of  FIG. 9 . In a case where the slide mechanism  10  is of a feed screw method, a user rotates one of or both of the knobs of the horizontal and inclination adjustment knobs  52 , so that the user can adjust the slide mechanism  10  connected with the lenticular lens  5  in the horizontal direction of  FIG. 8 . When the horizontal and inclination adjustment knobs  52  are of a screw method, the position in the horizontal direction is less likely to deviate from the adjusted state because of the friction of the screw even if the user releases his or her hand from the horizontal and inclination adjustment knobs  52  after the user adjusts the horizontal and inclination adjustment knob  52 . 
         [0062]    Not only the position in the horizontal direction is adjusted but also the user grabs one of or both of the knobs of the horizontal and inclination adjustment knobs  52  at the right and the left and moves the knobs in the vertical direction and inclines the component connected with the rotation center screw  11  of the slide mechanism  10 , so that the user can also adjust the lenticular lens  5  in the inclination direction of  FIG. 9  with respect to the rotation center screw  11  serving as the center of rotation. In order to prevent deviation from the adjusted state after the inclination has been adjusted with the horizontal and inclination adjustment knobs  52  in the image display apparatus according to the fourth embodiment, the rotation center screw  11  maybe loosened while the inclination is adjusted with the horizontal and inclination adjustment knobs  52 , and the rotation center screw  11  maybe tightened after the inclination has been adjusted with the horizontal and inclination adjustment knobs  52 . 
         [0063]    In this case, the position adjustment mechanism of the image display apparatus according to the fourth embodiment refers to the horizontal and inclination adjustment knobs  52 . 
         [0064]    Therefore, in the image display apparatus according to the fourth embodiment, when the horizontal and inclination adjustment knobs  52  are adjusted, the lenticular lens  5  can be independently adjusted in the horizontal direction and in the inclination direction of  FIG. 9  with respect to the frame  9 . 
         [0065]    Further, in the image display apparatus according to the fourth embodiment, the lenticular lens  5  including the horizontal and inclination adjustment knobs  52  can be inclined, and therefore, this allows the user to make adjustment in a more intuitive manner. In addition, in the image display apparatus according to the fourth embodiment, the lenticular lens  5  can be easily adjusted at a time in the horizontal direction and the inclination direction of  FIG. 9  with respect to the frame  9  using the horizontal and inclination adjustment knobs  52 . 
       Fifth Embodiment 
       [0066]    An image display apparatus according to a fifth embodiment will be hereinafter explained with reference to  FIG. 10 . The fifth embodiment is different from the first embodiment only in a lenticular lens unit  81  and a horizontal and inclination adjustment knobs  82 , and the fifth embodiment is the same as the first embodiment except the description of the lenticular lens unit  81  and a horizontal and inclination adjustment knobs  82 , and therefore, the same portions are denoted with the same reference numerals, and detailed explanation thereabout is omitted.  FIG. 10  is a longitudinal sectional view illustrating a lenticular lens unit of the image display apparatus according to the fifth embodiment. 
         [0067]    As shown in  FIG. 10 , a lenticular lens  5  is connected via a rotation center screw  11  with a slide mechanism  10  provided at an upper portion of  FIG. 10  with respect to a frame  9 . The lenticular lens  5  is configured in such a manner that many inverted U-shaped cylindrical lenses  14  are arranged side by side. 
         [0068]    However, the horizontal adjustment knobs  12  and the inclination adjustment knobs  13 ,  42  are not separately provided, and instead, the horizontal and inclination adjustment knob  82  is provided. The horizontal and inclination adjustment knob  82  has such structure that the horizontal adjustment knob  12  and the inclination adjustment knobs  13 ,  42  are integrated. 
         [0069]    In this case, the horizontal and inclination adjustment knobs  82  are provided to connect with a component connected with the rotation center screw  11  and the slide mechanism  10 , and, for example, in a case where the slide mechanism  10  is of a direct-acting method, a user grabs one of or both of the knobs of the horizontal and inclination adjustment knobs  82  and moves the knobs in the horizontal direction, so that the user can adjust the slide mechanism  10  connected with the lenticular lens  5  in the horizontal direction of  FIG. 10 . In a case where the slide mechanism  10  is of a feed screw method, a user rotates one of or both of the knobs of the horizontal and inclination adjustment knobs  82 , so that the user can adjust the slide mechanism  10  connected with the lenticular lens  5  in the horizontal direction of  FIG. 10 . When the horizontal and inclination adjustment knobs  82  are of a screw method, the position in the horizontal direction is less likely to deviate from the adjusted state because of the friction of the screw even if the user releases his or her hand from the horizontal and inclination adjustment knobs  82  after the user adjusts the horizontal and inclination adjustment knob  82 . 
         [0070]    Not only the position in the horizontal direction is adjusted but also the user grabs one of or both of the knobs of the horizontal and inclination adjustment knobs  82  at the right and the left and moves the knobs in the vertical direction and inclines the component connected with the rotation center screw  11  of the slide mechanism  10 , so that the user can also adjust the lenticular lens  5  in the inclination direction of  FIG. 10  with respect to the rotation center screw  11  serving as the center of rotation. 
         [0071]    In order to prevent deviation from the adjusted state after the inclination has been adjusted with the horizontal and inclination adjustment knobs  82  in the image display apparatus according to the fifth embodiment, the rotation center screw  11  may be loosened while the inclination is adjusted with the horizontal and inclination adjustment knobs  82 , and the rotation center screw  11  maybe tightened after the inclination has been adjusted with the horizontal and inclination adjustment knobs  82 . 
         [0072]    In this case, the position adjustment mechanism of the image display apparatus according to the fifth embodiment refers to the horizontal and inclination adjustment knobs  82 . 
         [0073]    Therefore, in the image display apparatus according to the fifth embodiment, when the horizontal and inclination adjustment knobs  82  are adjusted, the lenticular lens  5  can be independently adjusted in the horizontal direction and in the inclination direction of  FIG. 10  with respect to the frame  9 . 
         [0074]    In addition, in the image display apparatus according to the fifth embodiment, the lenticular lens  5  including the horizontal and inclination adjustment knobs  82  can be inclined, and therefore, this allows the user to make adjustment in a more intuitive manner. Further, in the image display apparatus according to the fifth embodiment, the lenticular lens  5  can be easily adjusted at a time in the horizontal direction and the inclination direction of  FIG. 10  with respect to the frame  9  using the horizontal and inclination adjustment knobs  82 . 
       Sixth Embodiment 
       [0075]    An image display apparatus according to a sixth embodiment will be hereinafter explained with reference to  FIG. 11 . The sixth embodiment is different from the first embodiment only in a lenticular lens unit  61  and horizontal adjustment auxiliary knobs  62 , and the sixth embodiment is the same as the first embodiment except the description of the lenticular lens unit  61  and the horizontal adjustment auxiliary knobs  62 , and therefore, the same portions are denoted with the same reference numerals, and detailed explanation thereabout is omitted.  FIG. 11  is a longitudinal sectional view illustrating a lenticular lens unit of the image display apparatus according to the sixth embodiment. 
         [0076]    As shown in  FIG. 11 , a lenticular lens  5  is connected via a rotation center screw  11  with a slide mechanism  10  provided at an upper portion of  FIG. 11  with respect to a frame  9 . The lenticular lens  5  is configured in such a manner that many inverted U-shaped cylindrical lenses  14  are arranged side by side. 
         [0077]    In this case, the horizontal adjustment auxiliary knobs  62  (which may be hereinafter also referred to as horizontal adjustment auxiliary units) are provided at a lower portion of  FIG. 11  in the image display apparatus according to the fifth embodiment. For example, when there is a high level of friction between the print surface of the recording medium  1  and the surface of the lenticular lens  5 , it is difficult to slightly move the lenticular lens  5  with only the inclination adjustment knob  13  and the horizontal adjustment knob  12  provided at an upper portion of  FIG. 11 . 
         [0078]    In this case, in the image display apparatus according to the sixth embodiment, the horizontal adjustment auxiliary knobs  62  are adjusted at the same time, so that the adjusting force is applied to the lower portion of the lenticular lens  5 , and this allows the lenticular lens  5  to be slightly moved. 
         [0079]    It should be noted that the horizontal adjustment auxiliary knobs  62  are arranged to be in contact with the lenticular lens  5 , and, for example, when the horizontal adjustment auxiliary knobs  62  are of the direct-acting method, a user grabs one of or both of the knobs of the horizontal adjustment auxiliary knobs  62  at the right and the left and moves the horizontal adjustment auxiliary knobs  62  in a horizontal direction, and pushes or pulls the contact portions at the right and the left of the horizontal adjustment auxiliary knobs  62 , so that the adjusting force can also be applied to the lower portion of the lenticular lens  5 . Ina case where the horizontal adjustment auxiliary knobs  62  are of a feed screw method, a user rotates one of or both of the knobs of the horizontal adjustment auxiliary knobs  62 , and pushes or pulls the contact portions at the right and the left of the horizontal adjustment auxiliary knobs  62 , so that the adjusting force can also be applied to the lower portion of the lenticular lens  5 . When the horizontal adjustment auxiliary knobs  62  are of a screw method, the inclination is less likely to deviate from the adjusted state because of the friction of the screw even if the user releases his or her hand from the knobs of the horizontal adjustment auxiliary knobs  62  after the horizontal adjustment auxiliary knobs  62  have been adjusted. 
         [0080]    As described above, even when there is a high level of friction between the print surface of the recording medium  1  and the surface of the lenticular lens  5  in the image display apparatus according to the sixth embodiment, the horizontal adjustment auxiliary knobs  62  are adjusted at the same time, the adjusting force is also applied to the lower portion of the lenticular lens  5 , so that the user can slightly move the lenticular lens  5 . 
         [0081]    In this case, a single set of horizontal adjustment auxiliary knobs  62  are provided, but two or more sets of horizontal adjustment auxiliary knobs  62  may be provided. The horizontal adjustment auxiliary knobs  62  are combined with the slide mechanism  10 , the rotation center screw  11 , the horizontal adjustment knobs  12 , and the inclination adjustment knobs  13 , like the first embodiment. Alternatively, the horizontal adjustment auxiliary knobs  62  may be combined with the image display apparatuses according to the second embodiment to the fifth embodiment, and a position adjustment mechanism  6  according to another embodiment. 
       Seventh Embodiment 
       [0082]    An image display apparatus according to a seventh embodiment will be hereinafter explained with reference to  FIG. 12 . The seventh embodiment is different from the first embodiment only in a lenticular lens unit  71 , a lenticular lens  72 , a slide mechanism  73 , a rotation center screw  74 , horizontal adjustment knobs  75 , inclination adjustment knobs  76 , and the seventh embodiment is the same as the first embodiment except the description of the lenticular lens unit  71 , the lenticular lens  72 , the slide mechanism  73 , the rotation center screw  74 , the horizontal adjustment knobs  75 , and the inclination adjustment knobs  76 , and therefore, the same portions are denoted with the same reference numerals, and detailed explanation thereabout is omitted.  FIG. 12  is a longitudinal sectional view illustrating a lenticular lens unit of the image display apparatus according to the seventh embodiment. 
         [0083]    As shown in  FIG. 12 , the image display apparatus according to the seventh embodiment is an image display apparatus in which many inverted U-shaped cylindrical lenses  14  constituting the lenticular lens  72  are arranged side by side in the horizontal direction of  FIG. 12 . Therefore, the slide mechanism  73 , the rotation center screw  74 , the horizontal adjustment knobs  75 , and the inclination adjustment knobs  76  of the lenticular lens  72  are arranged at the left side of the lenticular lens  72 . 
         [0084]    Therefore, the horizontal adjustment knobs  75  do not adjust the position, in the horizontal direction of  FIG. 12 , of the lenticular lens  72  connected via the rotation center screw  74  with the slide mechanism  73 , but adjust the positions of the lenticular lens  72  in the vertical direction of  FIG. 10 . Likewise, the inclination adjustment knobs  76  make adjustment in the inclination direction of  FIG. 12  with respect to the rotation center screw  74  of the slide mechanism  73  serving as the center of rotation. 
         [0085]    As described above, the image display apparatus according to the seventh embodiment is an image display apparatus in which many inverted U-shaped cylindrical lenses  14  constituting the lenticular lens  72  are arranged side by side in the horizontal direction of  FIG. 12 . A user can adjust the position of the lenticular lens  72  in the vertical direction of  FIG. 12  by using the horizontal adjustment knobs  75 . In addition, the user can make adjustment in the inclination direction of  FIG. 12  by using the inclination adjustment knobs  76 . 
         [0086]    In the image display apparatus according to the seventh embodiment, the slide mechanism  73 , the rotation center screw  74 , the horizontal adjustment knobs  75 , and the inclination adjustment knobs  76  may not be arranged at the left side of the lenticular lens  72  but may be arranged at the right side thereof. In the image display apparatus according to the seventh embodiment, the slide mechanism  73 , the rotation center screw  74 , the horizontal adjustment knobs  75 , and the inclination adjustment knobs  76  are arranged at the left side or the right side of the lenticular lens  72  like the first embodiment. Alternatively, the position adjustment mechanism  6  of the image display apparatuses according to the second to sixth embodiments and other embodiments may be arranged at the left side or the right side of the lenticular lens  72 . 
         [0087]    According to the image display apparatus of at least one of the embodiments explained above, the recorded image  25  and the lenticular lens  5  can be positioned with a simple structure. 
         [0088]    It should be noted that the present invention is not limited to the embodiments explained above, and it is to be understood that the present invention may be modified in various manners. 
         [0089]    For example, the number of lenticular lenses  5  in the lenticular lens unit  4 ,  31 ,  41 ,  51 ,  61 ,  71 ,  81  has not been particularly mentioned, but the present invention is not limited to a single lenticular lens  5 . It should be understood that two or more lenticular lenses  5  may be provided. 
         [0090]    In short, the present invention is not limited to the embodiments as they are. When the present invention is carried out, it can be embodied upon modifying constituent elements without deviating from the gist thereof. Multiple constituent elements disclosed in the embodiments can be combined appropriately, and various modes may be formed. For example, some of constituent elements may be omitted from all the constituent elements disclosed in the embodiments. Further, constituent elements in different embodiments may be appropriately combined.