Abstract:
A three-dimensional image displaying apparatus includes: a casing; a pair of plates engaged at both sides of the casing and having a guide hole having a certain curvature at upper and lower portions and a fixing hole formed near the guide hole; a pair of support frames engaged at both inner sides of the casing, each having a lower portion engaged at a bottom of the casing by a hinge shaft and an engaging groove formed on an inner surface for thereby fixing a half mirror, said support frames being rotatable along the guide hole in upward and downward directions; and a varying means engaged at upper portions of the support frames for fixing the support frames at a certain angle, whereby it is possible to selectively use the apparatus as a 2D image displaying apparatus and a 3D image displaying apparatus by moving the half mirror upwardly or downwardly.

Description:
CLAIM OF PRIORITY 
     This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from my application APPARATUS FOR CONTROLLING A HALF MIRROR OF THREE-DIMENSIONS DISPLAY DEVICE filed with the Korean Industrial Property Office on May 17, 1999 and there duly assigned Ser. No. 17653/1999. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a 3D image displaying apparatus, and in particular to a half mirror varying apparatus for a 3D image displaying apparatus which is capable of selectively implementing a two dimensional and three dimensional image by varying a half mirror in an up and down direction. 
     2. Description of the Background Art 
     Generally, a 3D image displaying apparatus is an apparatus capable of displaying a three dimensional image using a visual difference between the images presented to the left and right eyes of a human. 3D image displaying apparatus are generally classified into apparatus using a glass method which uses a special glass, and apparatus using a lenticular method. Among apparatus of the glass method, there are a polarizing glass type, a liquid crystal shutter glass type, and an anaglyph type for thereby implementing a 3D image. In the above-described glass method, it is necessary to wear special glasses, which makes this method inconvenient. 
     In addition, among apparatus of the lenticular method, there are a direct viewing type in which a lenticular lens sheet is installed on a surface of a displaying apparatus such as a CRT, liquid display panel, etc., and a projection type in which an image is projected onto a lenticular lens sheet using a projector. In the projection-type lenticular method, a half mirror is engaged for projecting an image. 
     A conventional 3D image displaying apparatus includes a casing, a first image display apparatus engaged at a lower portion of the casing, a second image display apparatus engaged in a vertical direction with respect to the first image display apparatus, a half mirror installed at an angle of 45° with respect to the first and second image display apparatuses, and a pair of support frames for supporting the half mirror. 
     The pair of the support frames are installed in a diagonal direction at both sides of the casing. The upper and lower ends of the same are engaged to the casing by an engaging screw. A pair of the support frames are formed in a longitudinal rectangular bar shape, and a pair of engaging protrusions are formed on an inner surface of the same in a longitudinal direction for thereby forming an engaging groove. Therefore, both ends of the half mirror are installed into the engaging grooves of the support frames, so that the half mirror is engaged to the casing. 
     However, in the 3D image displaying apparatus, the half mirror is fixed at a certain angle, the half mirror may be used for only the 3D image displaying apparatus. In addition, in the case that the half mirror is inclined at a certain angle due to an external force, it is difficult to adjust the installation angle of the half mirror because it is fixed, so that it is impossible to correct a certain error. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide an improved half-mirror apparatus for three-dimensional image display. 
     A further object of the invention is to provide an apparatus which can be used as for 3D or 2D image display. 
     A still further object of the invention is to provide a half-mirror apparatus in which displacement of the half-mirror from the proper angle can be corrected. 
     Accordingly, the present invention provides a half mirror fixing apparatus which is capable of selectively using a 3D image displaying apparatus as a 2D or 3D displaying apparatus by varying a half mirror upwardly and downwardly. 
     To achieve the above objects, there is provided a 3D image displaying apparatus which includes a casing, a pair of plates engaged at both sides of the casing and having a guide hole having a certain curvature at upper and lower portions and a fixing bole formed near the guide hole, a pair of support frames engaged at both inner sides of the casing each having a lower portion engaged at a bottom of the casing by a hinge shaft and an engaging groove formed on an inner surface for thereby fixing a half mirror, said support frames being rotatable along the guide hole in upward and downward directions, and a handle engaged at upper portions of the support frames for fixing the support frames at a certain angle, whereby it is possible to selectively use a 2D image displaying apparatus and a 3D image displaying apparatus by moving the half mirror upward or downward. 
     The handle includes a rack gear formed at an upper portion of each of the support frames in a vertical direction, a pinion heat rotatably engaged on the inner surfaces of the plates and engaged with the rack gear, and a handle having one end protruded into an interior of the upper portion of the support frame, and the other end protruded to the outside through the guide bole for thereby being inserted into the fixing holes of the plates, whereby the handle is upwardly moved along the guide hole, and the other end of the handle is inserted into the fixing hole, and the pinion gear is rotated at a certain angle for thereby implementing an accurate adjustment. 
     The support frame includes a cubic space formed in its upper portion of the interior of the same for receiving one end of the handle therein, and a spring is engaged in the interior of the space, and one end of the spring elastically supports one end of the handle, and the other end of the spring elastically supports an inner surface of the cubic space. 
     The through hole is formed at a center of the pinion gear, and a hole is formed at a certain portion of each of a pair of the plates corresponding to the through hole, so that the handle is integrally engaged with the through hole through the hole, and the pinion gear is rotatable by an adjusting knob. 
     Additional advantages, objects and features of the invention will become more apparent from the description which follows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the invention, and may of the attendant advantages, thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein: 
     FIG. 1 is a perspective view illustrating a conventional 3D image displaying apparatus; 
     FIG. 2 is a perspective view illustrating a 3D image displaying apparatus and a varying apparatus of a half mirror engaged at the 3D image displaying apparatus according to the present invention; 
     FIG. 3 is an operation state view illustrating an operation state of a varying apparatus for a half mirror engaged at a 3D image displaying apparatus according to the present invention; 
     FIG. 4 is an enlarged perspective view illustrating a state that a rack gear and pinion gear of a varying apparatus of a half mirror are engaged according to the present invention; 
     FIG. 5 is a front cross-sectional view illustrating a state that a rack gear and pinion gear of a varying apparatus of a half mirror are engaged according to the present invention; and 
     FIG. 6 is a front cross-sectional view illustrating a front portion of a varying apparatus of a half mirror according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning now to the drawings, FIG. 1 is a perspective view illustrating the conventional 3D image displaying apparatus described above. As shown therein, the 3D image displaying apparatus  1  includes a casing  2 , a first image display apparatus  3  engaged at a lower portion of the casing  2 , a second image display apparatus  4  engaged in a vertical direction with respect to the first image display apparatus  3 , a half mirror  6  installed at an angle of 45° with respect to the first and second image display apparatuses  3  and  4 , and a pair of support frames  5  for supporting the half mirror  6 . 
     The pair of the support frames  5  are installed in a diagonal direction at both sides of the casing  2 . The upper and lower ends of the same are engaged to the casing  2  by an engaging screw  7 . A pair of the support frames  5  are formed in a longitudinal rectangular bar shape, and a pair of engaging protrusions  8  are formed on an inner surface of the same in a longitudinal direction for thereby forming an engaging groove  9 . Therefore, both ends of the half mirror  6  are installed into the engaging grooves  9  of the support frames  5 , so that the half mirror  6  is engaged to the casing  2 . 
     The embodiments of the present invention will now be explained with reference to the accompanying drawings. As shown in FIGS. 2 and 3, the 3D image displaying apparatus  10  includes a casing  11 , a first image display apparatus  13  engaged at a lower portion of the casing  11 , a second image display apparatus  12  engaged in a vertical direction with respect to the first image display apparatus  13 , a pair of plates  14  engaged at both sides of the casing  11  and each having a guide hole and a fixing hole  27  near the guide hole  16 , a pair of support frames  22  engaged at both inner sides of the casing  11  for fixing the half mirror  15  and being movable upwardly and downwardly along the guide hole  16 , and a fixing member  20  for fixing the support frames  22 . 
     The plates  14  are engaged at both sides of the casing  11  by an engaging screw  17 , and a guide hole  16  having a certain curvature is formed at each plate  14 . In addition, a fixing hole  27  is formed at a portion spaced-apart in an upward direction from the guide hole  16 . 
     A pair of the support frames  22  are formed in a longitudinal rectangular bar, and a pair of engaging protrusions are formed on an inner surface in a longitudinal direction for thereby forming an engaging groove  21 . In addition, both ends of the half mirror  15  are inserted into the engaging groove  21 . Therefore, the half mirror  15  is fixed at a pair of the support frames  22 . 
     As shown in FIGS. 4 and 5, the fixing member  20  includes a rack gear  25  formed at an upper portion of each support frame  22 , a handle  24  protruded from one side of each of the support frame  22 , and a pinion gear  23  engaged with the rack gear  25 . 
     The rack gear  25  is protruded in a vertical direction from an upper portion of the support frame  22 . A gear  25   a  is formed at a lower portion of the same, and the rack gear  25  is engaged with the pinion gear  23 . The pinion gear  23  is a dial type gear to which a certain tension force is applied. Therefore, the half mirror may be positioned at a certain portion by rotating the pinion gear  23  in a clockwise direction or a counterclockwise direction. In this state, a tension force is applied, it is possible to support a certain weight. 
     Referring to FIG. 4, an adjusting knob  26  is integrally engaged with the pinion gear  23 . Namely, a through hole  23   a  is formed at a center portion of the pinion gear  23 . A hole  29  is formed at a certain portion of the plates corresponding to the through hole  23   a,  and the adjusting knob  26  is integrally engaged with the through hole  23   a  through the hole  29 . 
     Therefore, when rotating the adjusting knob  26  in a first arrow direction  37 , the pinion gear  25  is rotated in a second arrow direction  36 , and the rack gear  25  is rotated at a certain angle, so that it is possible to accurately control the half mirror  15 . 
     The handle  24  is formed in a channel shape protruded from the support frame  22 . One end  24   b  of the handle  24  is inserted into a cubic space  32  formed in the upper inner portion of the support frame  22  through an inlet hole  32   a.  In addition, the other end  24   a  of the handle  24  is protruded to the outside through the guide hole  16  of the casing  11  and is movably inserted into the fixing hole  27  formed at the casing  11 . 
     Therefore, when a user holds the handle  24  and rotates the support frame  22  along the guide hole  16  in an upward and downward direction, the other end  24   b  of the handle  24  is inserted into the fixing hole  27  for thereby fixing the half mirror  15 . After the half mirror  15  is fixed, the adjusting knob  26  is rotated, so that it is possible to accurately adjust the angle of the half mirror  15 . 
     At this time, since the fixing hole  27  is a longitudinal shape, in a state that the handle  24  is inserted into the fixing hole  27 , the handle  24  is movable therein for thereby implementing an accurate adjustment. In addition, a spring  31  is engaged in the interior of the cubic space  32 . One end of the spring  31  is elastically supported by one side  24   c  of the end portion  24   b  of the handle  24 , and the other end of the spring  31  is supported by an inner side  32   b  of the cubic space  32 . 
     Therefore, the spring  31  elastically pushes one end  24   b  of the handle  24  in an inner direction of the casing  11 . In the casing of using the handle  24 , the handle  24  is pulled in an outer direction of the casing  11  along a third arrow direction  38 . 
     As shown in FIG. 6, a hinge shaft  19  is protruded from a lower portion of the support frame  22 . In addition, the hinge shaft  19  is hingedly engaged to a support bracket  34  protruded from a lower surface of the casing  11 . Therefore, the handle  24  is held and moved in a fourth arrow direction  33  (shown in FIG.  3 ), the support frame  22  is moved at a certain angle upward or downward about the hinge shaft  19 . As a result, the half mirror  15  is moved upward or downward. 
     In the case of using the half mirror  15 , the handle  24  is held and moved upward along the guide hole  16  (shown in FIG.  3 ), so that the rack gear  25  is engaged with the pinion gear  23 . In addition, the adjusting knob  26  is rotated for an accurate adjustment. The other end  24   a  of the handle  24  (refer to FIG. 5) is fixedly inserted into the fixing hole  27 . 
     In the case that the half mirror  15  is not used, the support frame  22  is moved to the lower potion  16   a  along the guide hole  16  (refer to FIG.  3 ), so that it is possible to implement a 2D image apparatus. 
     The operation of the present invention will be explained with reference to the accompanying drawings. As shown in FIGS. 2 through 6, in the case that a user wishes to use the 3D image displaying apparatus  10  as a 3D image displaying apparatus, the handle  24  is held and pushed upwardly along the fourth arrow direction  33 . Therefore, the support frame  22  is rotated in an upward direction about the hinge shaft  19 , and the rack gear  25  is moved upwardly along the guide hole  16 . At this time, the handle  24  is pulled in an outer direction of the casing  10 , so that the other end  24   a  of the handle  24  does not interfere with the upper portion of the guide hole  16 . 
     The support frame  22  is moved upward, and the other end  24   a  of the handle  24  is positioned at the fixing hole  27 . In this state, when the user stops holding the handle  24 , the handle  24  is moved into the interior of the casing  10  by an elastic force of the spring  31 . In addition, the other end  24   a  of the handle  24  is inserted into the fixing hole  27 . 
     At this time, the rack gear  25  is engaged with the pinion gear  23 . Therefore, the adjusting knob  26  is rotated, and the pinion hear  23  is rotated at a certain angle along the first arrow direction  37 . Therefore, the rack gear  37  engaged to the pinion gear  23  is moved along the second arrow direction  36  for thereby implementing an accurate adjustment. At this time, since the fixing hole is longitudinal, the other end  24   a  of the handle  24  is movable upward or downward in the interior of the fixing hole  27 . 
     In the case that the 3D image displaying apparatus  10  is used as a 2D image displaying apparatus, a user holds the handle  24  and ejects the same to the outside along the third arrow direction  38 . Therefore, the other end  24   a  of the handle  24  inserted into the fixing hole  27  is removed from the fixing hole. In this state, the user continuously moves the handle  24  in the fourth arrow direction  33 . 
     At this time, the engaged state of the rack gear  25  and the pinion gear  23  is released, and the rack gear  25  is moved downward. In addition, when the handle  24  contacts the lower portion  16   a  of the guide hole  16 , the half mirror  15  maintains a horizontal state. Therefore, the user can use the apparatus as a 2D image displaying apparatus. 
     As described above, in the present invention, there is an advantage in that the image displaying apparatus according to the present invention may be selectively used as a 2D image displaying apparatus or a 3D image displaying apparatus by moving the displaying apparatus upwardly or downwardly. 
     Although the preferred embodiment of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as recited in the accompanying claims.