Patent Publication Number: US-2012026112-A1

Title: Image display apparatus and method thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from and the benefit under 35 U.S.C. §119 of Korean Patent Application No. 10-2010-00073199, filed on Jul. 29, 2010, which is hereby incorporated by reference for all purposes as if fully set forth herein. 
     BACKGROUND 
     1. Field 
     This disclosure relates to a stereographic image display, and more particularly, to a stereographic image display apparatus having a touch function and a manufacturing method thereof. 
     2. Discussion of the Background 
     An autostereographic image technology may be implemented using a parallax phenomenon, which relies on a person&#39;s two eyes viewing a display in a different manner. In order to utilize parallax, a display element has an ability to display a pixel for the left eye and the right eye distinctly. This may be implemented by using an image filter for individually displaying a left eye image and a right eye image. Specifically, the image filter may be implemented with autostereographic images, a parallax barrier, a lenticular lens, and the like. 
     In the case of a stereographic method utilizing a lenticular lens, a lenticular lens is disposed on a display through which an image is viewed such that a pixel line for the left eye and a pixel line for the right eye are alternately arranged in a direction. The lenticular lens may then be used to display a left eye image and a right eye image using a light refraction phenomenon, thus providing stereographic effects. 
       FIG. 1  ( a ) is a diagram illustrating a stereographic image method using a lenticular lens. 
     Referring to  FIG. 1  ( a ), the display element  11  and a lenticular lens  12  are adhered to an optically clear adhesive (OCA)  13  disposed therebetween. The lenticular lens  12  allows for a right and left eye to see different images. 
       FIG. 1  ( b ) is a diagram schematically illustrating a cross-sectional structure of a capacitive touchscreen. 
     The touch screen mainly includes two transparent films  21  and  22  on which transparent electrode layers  31  and  32  are deposited, respectively, and a protection film  51 . The transparent films  21  and  22  are adhered through optically clear adhesives  41  and  42 . 
     There are numerous disadvantages to providing autostereographic images and a touch screen together. If the touchscreen is attached to the autostereographic image display, image quality degradation occurs, and there are problems caused by the thickness of the entire display apparatus being increased. Further, material costs and manufacturing costs are increased. 
     SUMMARY 
     The following description relates to an image display apparatus and method thereof according to various embodiment contained herein. 
     An exemplary embodiment provides for an image display apparatus, including an image display unit which includes pixels in a matrix form and in which a pixel for the left eye and a pixel for the right eye are arranged alternately in each pixel; and a touch sensing unit positioned on the image display unit, the touch sensing unit comprises: a lens array interposed between a first transparent electrode layer and a second transparent electrode layer that intersect each other, wherein the touch sensing unit senses a touch or touch position by the first transparent electrode layer and the second transparent electrode layer, and separates an image output from the image display unit through the lens array into a left eye image and a right eye image based on a refractive index of light. 
     Another exemplary embodiment provides a manufacturing method of a stereographic image display apparatus including disposing a transparent conductive material on opposing sides of a lens array; forming a first transparent electrode layer and a second transparent electrode layer by etching the transparent conductive material deposited on the lens array to generate a touch sensing unit; and adhering the touch sensing unit to an image display unit. 
     Another exemplary embodiment provides a 3D image display apparatus, including a lens array with pixels for a right eye image and a left eye image, to separate an image output from the image display unit with a refractive index of light for the right eye image and the left eye image; a first transparent electrode layer disposed on a first side of the lens array; a second transparent electrode layer disposed on a second side of the lens array, wherein the first transparent electrode and the second transparent electrode are disposed in directions to intersect with each other and configured to sense a touch. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. Other features and aspects will be apparent from the following detailed description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention. 
         FIG. 1(   a ) is a diagram illustrating a structure of a stereographic image display according to the related arts. 
         FIG. 1(   b ) is a diagram illustrating a structure of a touch screen according to the related arts. 
         FIG. 2  is a perspective view of a stereographic display apparatus according to an exemplary embodiment. 
         FIG. 3  is a cross-sectional view illustrating an I-I′ section of a stereographic display apparatus according to an exemplary embodiment. 
         FIG. 4  is a cross-sectional view schematically illustrating a stereographic image display apparatus according to an exemplary embodiment. 
         FIG. 5A ,  FIG. 5B ,  FIG. 5C  and  FIG. 5D  are diagrams illustrating a manufacturing of a stereographic image display apparatus according to an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments now will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth therein. Rather, these exemplary embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of this disclosure to those skilled in the art. In the description, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the presented embodiments. It is to be understood that if an element is described as being “disposed on” another element, it may be disposed directly on the other element or intervening elements may be present. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, the use of the terms a, an, etc. does not denote a limitation of quantity, but rather denotes the presence of at least one of the referenced item. It will be further understood that the terms “comprises” and/or “comprising”, or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     In the drawings, like reference numerals in the drawings denote like elements. The shape, size and regions, and the like, of the drawing may be exaggerated for clarity. 
       FIG. 2  is an exploded perspective view of a stereographic display apparatus according to an exemplary embodiment.  FIG. 3  is a cross-sectional view illustrating an I-I′ section of  FIG. 2 .  FIGS. 2 and 3  illustrate a structure in which a display element for a stereographic image and a touchscreen function are integrated. 
     The stereographic display apparatus according to an exemplary embodiment includes an image display unit  110  to output an image, a lens array  122  to separate the image output from the image display unit  110  in a left eye direction and a right eye direction, first and second transparent electrode layers  121  and  123  disposed on both surfaces of the lens array  122 , and a protection layer  130 . 
     The image display unit  110 , the lens array  122  on which the first and second transparent electrode layers  121  and  123  are disposed, and the protection layer  130  are directly adhered. However, aspects of the present invention are not limited thereto such that intervening layers may be present between any of the layers  110 ,  121 ,  122 ,  123  and  130 . The adhering process may be performed using heat, pressure, and the like without additional adhesives being used, as illustrated. The first transparent electrode layer  121  is disposed on one side of a touch sensing unit  120  and is adhered to the image display unit  110 , and the protection layer  130  is adhered to the second transparent electrode layer  123  formed at a second side of the touch sensing unit  120 . If the use of optically clear adhesives is minimized and corresponding layers are removed, the thickness of the entire apparatus can be reduced, material costs can be reduced, and image quality degradation due to the optically clear adhesives may be avoided. 
     The image display unit  110  may be a display such as a liquid crystal display (LCD) panel or an organic light emitting diode (OLED) panel and may include pixels in a matrix form. In the image display unit  110 , a pixel line for the left eye and a pixel line for the right eye may intersect in various directions, with each pixel including at least a pixel for the left eye and a pixel for the right eye arranged alternately with each other. The image display unit  110  outputs a separate image through each of the pixel for the left eye and the pixel for the right eye, and thus allows the two eyes to see different images and to perceive the different images, causing the two eyes to see a stereographic image. 
     The lens array  122  is disposed on the image display unit  110 . The lens array  122  provides an autostereographic image and may be a convex lens type or a concave lens type lenticular lens, or the like. 
     The lens array  122  may be an image filter of an optical structure using a light refraction phenomenon that displays the left eye image and the right eye image by separating the images input to the lens array  122  from the image display unit  110  into left and right side images based on the refractive index of light. Due to the lens array  122  using light refraction, the lens array  122  may be designed in consideration of various factors, including the pixels for the left eye and the pixels for the right eye of the image display unit  110 , the size and shape of the lens, distances, and the like. 
     The hemispheres of the lenses of the lens array  122  are aligned with the pixels for the left eye and the pixels for the right eye of the image display unit  110  and positioned so that the left eye image and the right eye image are separated through each lens of the lens array  122  into a stereographic image. A focal region in which a stereographic image is seen is formed by changing the transmittance of light using a fixed hemispheric lens. For this, the image display unit  110  separately operates the display of a pixel for the left eye and the pixel for the right eye, thereby producing images contents separately produced for stereographic images for each eye. In a case of displaying a 2D image, such as text, which does not require a stereographic image, the same image may be displayed on the pixel for the left eye and the pixel for the right eye. 
     The lens array  122 , the first transparent electrode layer  121 , and the second transparent electrode layer  123  are disposed on the image display unit  110  and collectively compose the touch sensing unit  120 . The touch sensing unit  120  may filter the image to separate the image output from the image display unit  110  into images for the left eye and for the right image based on the refractive index of light, and provide touchscreen functionality. 
     The touch sensing unit  120  may be an integrated structure in which the lens array  122  is disposed between the first and second transparent electrode layers  121  and  123 . The images output from the image display unit  110  are separated for the left eye and right eye directions based on the refractive index of light through the lens array  122 . 
     The touch sensing unit  120  may be a capacitive touchscreen in which the first and second transparent electrode layers  121  and  123 , are disposed irrespective of the first and second sides of the translucent lens array  122 . In this case, the touch sensing unit  120  senses a touch position by sensing changes in static electricity and current between the first and second transparent electrode layers  121  and  123 , which are deformed when touched to change an interval by which the first and second transparent electrode layers  121  and  123  are separated. The first and second transparent electrode layers  121  and  123  may be formed into a matrix pattern (or in a perpendicular orientation) to determine a touch, and touch position of the touch, on the touch sensing unit  120 . For example, the pattern of the first transparent electrode layer  121  is formed in a first direction, and the pattern of the transparent electrode layer  123  may be formed in a second direction that crosses the first direction. 
     The protection layer  130  may be a protection film or a protection glass to cover a side of the touch sensing unit  120 , and may be maintained at a specific height so as not to deform or break the outer shapes of the lens hemispheres on the lens array  122  when pressed by a pressure exerted during a touch input. 
     According to exemplary embodiments, the touch sensing unit  120  may be attachable to a display device such that the touch sensing unit  120  may be attached or detached according to a user&#39;s requirement. 
     The touch sensing unit  120  may implement the integrated structure by depositing a transparent conductive material on and under the lens array  122 . In this structure, the use of a transparent film and/or an optically clear adhesive as a supporting material of the transparent conductive material on the touchscreen may be omitted or reduced. In addition, due to the above reasons, since the transparent film and the optically clear adhesive for attaching it are omitted, the thickness of the entire apparatus can be reduced, and material costs may be reduced, and the transmittance may be enhanced, thereby providing a high quality image. In addition, the manufacturing process can be simplified, thereby minimizing defects. 
       FIG. 4  is a cross-sectional view schematically illustrating a stereographic image display apparatus according to an exemplary embodiment. 
     In  FIG. 4 , a structure in which the image display unit  110  is adhered to the touch sensing unit  120  including the lens array  122  by first and second optically clear adhesive layers  141  and  142  made of optically clear adhesives in a similar structure as illustrated in  FIGS. 2 and 3  is illustrated. The first transparent electrode layer  121  disposed on a first side of the touch sensing unit  120  is adhered to the image display unit  110  through the first optically clear adhesive layer  141 , and the second transparent electrode layer  123  disposed on a second side of the touch sensing unit  120  is adhered to the protection layer  130  by the second optically clear adhesive layer  142 . 
     As shown in  FIGS. 2 to 4 , the lens array  122  and the first and second transparent electrode layers  121  and  123  may be integrated, thereby reducing the number of layers. In addition, due to the exclusion of a transparent film, advantages such as a reduction in the thickness of the entire apparatus, a reduction in material cost, and improvement of image degradation due to the transparent film may be achieved. 
       FIG. 5A ,  FIG. 5B ,  FIG. 5C  and  FIG. 5D  are diagrams illustrating a manufacturing of a stereographic image display apparatus according to an exemplary embodiment. 
     As illustrated in  FIG. 5A , transparent conductive materials  124  and  125  are subjected to vacuum deposition to be formed as thin films on the both surfaces of the lens array  122 . The conductive materials may be formed of or include indium tin oxide (ITO), indium zinc oxide (IZO), or the like. 
     Thereafter, as illustrated in  FIG. 5B , the first and second transparent electrode layers  121  and  123  are formed by etching the transparent conductive materials  124  and  125  deposited on the both surfaces of the lens array  122 . This may be done through the process exemplified in  FIG. 5A , thereby sequentially disposing the first transparent electrode  121 , the lens array  122 , and the second transparent electrode layer  123 . Accordingly, the touch sensing unit  120  having an integrated image filter and capacitive touchscreen may be realize. The first and second transparent electrode layers  121  and  123  may be formed into a matrix pattern (or in perpendicular orientation) to determine a touch, and a position of the touch, on the touch sensing unit  120 . For example, the pattern of the first transparent electrode layer  121  may be formed in a first direction, and the pattern of the transparent electrode layer  123  may be formed in a second direction disposed to cross the first direction. 
     As illustrated in  FIG. 5C , the touch sensing unit  120  is adhered to a surface of the image display unit  110 . As illustrated in  FIG. 5D , the protection layer  130  is disposed on the touch sensing unit  120  opposite the image display unit  110 . However aspect are not limited thereto such that the protection layer  130  may be removed or replaced with other materials. 
     The image display unit  110 , the touch sensing unit  120 , and the protection layer  130  may be directly adhered using heat, pressure, and the like without use of the optically clear adhesives or may be adhered using optically clear adhesives. If the optically clear adhesive is used as a material for interlayer adhesion, as illustrated in  FIG. 4 , the upper surface of the image display unit  110  may be adhered to the touch sensing unit  120  using the first optically clear adhesive layer  141 , and the protection layer  130  may be adhered to the upper surface of the touch sensing unit  120  using the second optically clear adhesive layer  142 . 
     It will be apparent to those skilled in the art that various modifications and variation can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.