Patent Publication Number: US-2013250072-A1

Title: 2d/3d display and method for forming 3d image

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application of and claims priority benefit of application Ser. No. 11/935,475, filed on Nov. 6, 2007, now pending, which is a divisional application of and claims priority benefit of application Ser. No. 11/117,257, filed on Apr. 28, 2005, now U.S. Pat. No. 7,477,331, which is based upon and claims the benefit of priority from the prior Taiwan Patent Application No. 94103365, filed on Feb. 3, 2005. The entirety of each of the above-mentioned patent applications is hereby fully incorporated herein by reference and made a part of this specification. 
    
    
     BACKGROUND 
     The invention relates to a flat panel display and in particular to a flat panel display capable of providing 2D and 3D images. 
     In a conventional stereoscopic or three-dimensional (3D) display, users are required to wear a device, such as a shutter or polarization glasses, that ensure left and right views are seen by the correct eye. Such a stereoscopic display, however, suffers from the drawback that the viewers must wear, or be very close to, the device to separate left and right eye views. 
     Recently, many stereoscopic display designs, such as lenticular and parallax designs have been proposed which do not require use of shutter or polarization glasses. In these stereoscopic display devices, specific optical devices such as lenticular lens or parallax barriers are generally disposed on the front or rear sides of image display devices. For example, a simple stereoscopic image display device can be easily constituted by a combination of such parallax barriers and a two-dimensional (2D) display device, such as a liquid crystal display (LCD). Half the pixels of the display device radiate light only in directions seen by the left eye and half the pixels in directions seen by the right eye through the parallax barrier, creating twin-view stereoscopic images. Conventionally, the parallax barrier comprises a retarder which suffers from the drawback of difficult alignment between the LCD and the parallax barrier. 
     U.S. Pat. No. 6,157,424 discloses a 2D/3D image display, in which two LCDs are employed. One of the LCDs provides image information and the other parallax barrier image patterns. LCDs, however, suffer from the drawback of higher power consumption due to back light device. 
     SUMMARY 
     A 2D/3D display and methods for forming a 3D image are provided. An embodiment of a 2D/3D display comprises a liquid crystal display device and a self-emissive display device. The liquid crystal display device provides a first image. The self-emissive display device is disposed on the rear of the liquid crystal display device, providing a backlight source and a second image. One of the first and second images comprises a parallax barrier pattern for forming a 3D image, and the other is a 2D image. 
     An embodiment of a method for forming a 3D image comprising forming a 2D image by a liquid crystal display device is provided. An image with a parallax barrier pattern is formed behind the 2D image by a self-emissive display device, such that a viewer sees a 3D image from the liquid crystal display device side by transferring the 2D image through the parallax barrier pattern. 
     Additionally, an embodiment of a method for forming a 3D image comprising forming a 2D image by a self-emissive display device is provided. An image with a parallax barrier pattern is formed in front of the 2D image by a liquid crystal display device, such that a viewer sees a 3D image from the liquid crystal display device side by transferring the 2D image through the parallax barrier pattern. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       A 2D/3D display and methods for forming a 3D image will become more fully understood from the detailed description given hereinbelow and the accompanying drawings, given by way of illustration only and thus not intended to be limitative of the invention. 
         FIGS. 1   a  and  2   a  are cross-sections of embodiments of 2D/3D display of the invention. 
         FIGS. 1   b,    1   c,    2   b,  and  2   c  are cross-sections of embodiments of methods for forming a 3D image of the invention. 
         FIGS. 3   a  and  3   b  are cross-sections of embodiments of parallax barrier patterns of the invention. 
         FIG. 4  is a schematic diagram of relative positions of a viewer and a display. 
         FIG. 5   a  is a schematic diagram of a 2D image fully overlapping a parallax barrier pattern. 
         FIG. 5   b  is a schematic diagram of a 2D image partially overlapping a parallax barrier pattern. 
     
    
    
     DETAILED DESCRIPTION 
     A 2D/3D display and methods for forming a 3D image will be described in greater detail in the following.  FIGS. 1   a  and  2   a  illustrate embodiments of 2D/3D display  100 . The display  100  comprises a self-emissive display device  102 , a liquid crystal display device  104 , a detector device  108 , and a control device  110 . The liquid crystal display device  104  provides a first image, such as a 2D image. Typically, the liquid crystal display device  104  comprises an upper substrate  104   b,  a lower substrate  104   a,  and a liquid crystal layer  104   c  interposed between the upper and lower substrates  104   b  and  104   a,  wherein color filters (not shown) may be disposed on the upper or lower substrate  104   b  or  104   a.  The self-emissive display device  102  is disposed on the rear of the liquid crystal display device  104 , serving as a backlight source for the liquid crystal display device  104  and providing a second image, such as a 2D image. In this embodiment, the self-emissive display device  102  may comprise a plasma display device, an organic light-emitting device, or other electroluminescent display device. The first or second image presented on display  100  in a 2D mode may comprise a clear pattern. For example, the self-emissive display device  102  only serves as a backlight source without providing any image information (that is, a clear pattern). The 2D image information is provided by the liquid crystal display device  104 . Conversely, the 2D image information may be provided by the self-emissive display device  102 , while the liquid crystal display device  104  does not display any image information. Moreover, the first or second image may provide a parallax pattern formed by a 2D image when the display in a 3D mode. For example, the parallax barrier pattern may be provided by the self-emissive display device  102 . The 2D image information provided by the liquid crystal display device  104  may be transformed into the 3D image information through the parallax barrier pattern. Conversely, the parallax barrier pattern may be provided by the liquid crystal display device  104 . The 2D image information provided by the self-emissive display device  102  may also be transformed into the 3D image information through the parallax barrier pattern. In this case, the liquid crystal display device  104  may not require color filters. 
     The detector device  108  is coupled to the liquid crystal display device  104 , measuring a distance between a viewer and the display  100 . Moreover, the control device  110  is coupled to the display device providing the parallax barrier pattern, such as the self-emissive display device  102  (as shown in  FIG. 1   a ) or the liquid crystal display device (as shown in  FIG. 2   a ), thereby adjusting the parallax barrier pattern in the 3D mode according to the distance between a viewer and the display  100 . 
       FIG. 1   b  illustrates an embodiment of a method for forming a 3D image. A 2D image  103  is provided by the liquid crystal display device  104 . Another 2D image with a parallax barrier pattern is provided by the self-emissive display device  102  disposed on the rear of the liquid crystal display device  104 , such that a 3D image  103  is observed by a viewer from the liquid crystal display device  104  side by transferring the 2D image  103  through the parallax barrier pattern  101 . 
       FIGS. 3   a  and  3   b  illustrate embodiments of parallax barrier patterns  101 . In  FIG. 3   a , the parallax barrier pattern  101  comprises a plurality of dark strips  101   a  parallel to each other. In  FIG. 3   b , the parallax barrier pattern  101  comprises a plurality of dark strips  101   a  perpendicular to each other. The 2D image  103  may fully overlap the parallax barrier pattern  101 , as shown in  FIG. 5   a , thereby completely transforming the 2D image  103  provided by the liquid crystal display device  104  into a 3D image. 
       FIG. 1   c  illustrates another embodiment of a method for forming a 3D image. In this embodiment, the difference from  FIG. 1   b  is that the 2D image provided by the self-emissive display device  102  comprises a clear pattern and at least one parallax barrier pattern, such that the 2D image  103  in front of the parallax barrier pattern is transferred into the 3D image and that in front of the clear pattern is maintained without being transferred, as it is observed by a viewer from the liquid crystal display device  104  side. That is, the display  100  may simultaneously display 2D and 3D images. In this embodiment, the parallax barrier pattern partially overlaps the 2D image  103 . Moreover, the number and size of the parallax barrier pattern and the position thereof with respect to the 2D image  103  can be adjusted according to demands, as shown in  FIG. 5   b.    
       FIG. 2   b  illustrates yet another embodiment of a method for forming a 3D image. In this embodiment, the difference from  FIG. 1   b  is that the 2D image  103  is provided by the self-emissive display device  102  and the 2D image with the parallax barrier pattern  101  provided by the liquid crystal display device  104  in front of the self-emissive display device  102 , such that the 2D image  103  provided by the self-emissive display device  102  is transferred into the 3D image through the parallax barrier pattern  101 , as it is observed by a viewer from the liquid crystal display device  104  side. 
       FIG. 2   c  illustrates further another embodiment of a method for forming a 3D image. In this embodiment, the difference from  FIG. 2   b  is that the 2D image provided by the liquid crystal display device  104  comprises a clear pattern and at least one parallax barrier pattern, such that the 2D image  103  behind the parallax barrier pattern is transformed into the 3D image and the 2D image  103  behind the clear pattern is maintained without being transferred, as it is observed by a viewer from the liquid crystal display device  104  side. 
       FIG. 4  is a schematic diagram of the relative positions of a viewer  10  and a display  100 . In the embodiments of  FIGS. 1   b,    1   c,    2   b,  and  2   c,  a perpendicular distance L and a parallel distance of the viewer  10  to the center of the display  100  can further be measured. Next, in the parallax barrier pattern  101  (as shown in  FIG. 3   a  or  3   b ), the width of each dark strip  101   a  and the space therebetween can be adjusted according to the perpendicular distance L. Moreover, the shift of the dark strips  101   a  in a perpendicular direction can be adjusted according to the parallel distance d. 
     According to the 2D/3D display of the invention, since the self-emissive display device does not require a backlight device, power consumption can be reduced. Moreover, since the parallax barrier pattern is provided by the self-emissive display device or the liquid crystal display device, the 2D and/or 3D images can be provided. Furthermore, the relative positions between the 2D and 3D images can be randomly changed by adjusting the number, size, and position of the parallax barrier pattern. 
     While the invention has been described by way of example and in terms of preferred embodiment, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation to encompass all such modifications and similar arrangements.