Abstract:
An exemplary liquid crystal display includes a thin film transistor (TFT) substrate, a color filter substrate opposite to the TFT substrate, and a liquid crystal layer sandwiched between the TFT substrate. The color filter substrate includes a plurality of color units and a first infrared detection layer arranged between the color units. The first infrared detection layer is configured to detect infrared light beams irradiating thereon and determine an irradiated position thereof. A remote control display system employing the liquid crystal display is also provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is related to, and claims the benefit of, a foreign priority application filed in Taiwan as Application No. 097110103 on Mar. 21, 2008. The related application is incorporated herein by reference. 
     FIELD OF THE DISCLOSURE 
     The present disclosure relates to a liquid crystal display (LCD) that includes an infrared detection layer, and a remote control display system employing the liquid crystal display. 
     GENERAL BACKGROUND 
     Recently, liquid crystal displays that are light and thin and have low power consumption characteristics have been widely used in office automation equipment, video units, and the like. Generally, a liquid crystal display having touch panel function is achieved by stacking a transparent touch panel on a liquid crystal panel. The touch panel mounted on the liquid crystal panel display acts as an interface or a medium for inputting of signals by a user. However, the touch panel of the liquid crystal display generally needs to be physically contacted, i.e. by a person&#39;s finger or a touch pen, to utilize touch control function. This may result in an inconvenient operation in some situations, such as large-sized display, teaching classes, or speeches. 
     What is needed, therefore, is a liquid crystal display that can overcome the described limitations, as well as a remote control display system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of at least one embodiment of the present disclosure. In the drawings, like reference numerals designate corresponding parts throughout various views, and all the views are schematic. 
         FIG. 1  is a side, cross-sectional view of a remote control display system according to a first embodiment of the present disclosure, the remote control display system including a liquid crystal display and a light beams generator, the liquid crystal display including a thin film transistor (TFT) substrate and a color filter substrate located opposite to each other. 
         FIG. 2  is a top, plan, partial view of the TFT substrate of the liquid crystal display of  FIG. 1 . 
         FIG. 3  is a bottom, plan, partial view of the color filter substrate of the liquid crystal display of  FIG. 1 . 
         FIG. 4  is a side, cross-sectional view of a remote control display system according to a second embodiment of the present disclosure, the remote control display system including a liquid crystal display having a color filter substrate. 
         FIG. 5  is a bottom, plan, partial view of the color filter substrate of the liquid crystal display of  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Reference will now be made to the drawings to describe preferred and exemplary embodiments in detail. 
     Referring to  FIG. 1 , a remote control display system  10  according to a first embodiment of the present disclosure is shown. The remote control display system  10  includes a light beams generator  140  configured to generate visible light beams and infrared light beams, and a liquid crystal display  100  configured to display information and detect the infrared light beams from the light beams generator  140 . 
     The liquid crystal display  100  includes a TFT substrate  130 , a color filter substrate  110 , and a liquid crystal layer  120  sandwiched between the TFT substrate  130  and the color filter substrate  110 . Referring also to  FIG. 2 , the TFT substrate  130  includes a first glass substrate  131 , a plurality of display units  132 , a plurality of data lines  133 , a plurality of scanning lines  134 , and a plurality of TFTs  135 . The display units  132  are regularly arrayed at the first glass substrate  131 . The data lines  133  are parallel to each other, each extending along a first direction. The scanning lines  134  are parallel to each other, each extending along a second direction orthogonal to the first direction. The TFTs  135  function as switching elements, and each is provided in the vicinity of a respective point of intersection of the data lines  133  and the scanning lines  134 . 
     Referring to  FIG. 3 , the color filter substrate  110  includes a second glass substrate  111 , a color filter layer  112 , a black matrix  113 , an infrared detection layer  114 , a plurality of first buses  115 , a plurality of second buses  116 , a plurality of first leads  117 , and a plurality of second leads  118 . The color filter layer  112  includes a plurality of red (R), green (G), and blue (B) color units (not labeled) corresponding to the display units  132  of the TFT substrate  130 , respectively. 
     The infrared detection layer  114  is configured to sense infrared light beams. The infrared detection layer  114  is arranged at the second glass substrate  111 , and surrounds each color unit, thus defining a plurality of detection blocks (not labeled). The detection blocks correspond to the TFTs  135  of the TFT substrate  130 , respectively. The infrared detection layer  114  includes a plurality of P-areas (not labeled) and N-areas (not labeled) doped on the second glass substrate  111 , and a plurality of PN-junctions formed between the adjacent P-areas and N-areas. 
     The first buses  115  and the second buses  116  are arranged at the second glass substrate  111 , and are between the infrared detection layer  114 . The first leads  117  are connected to the P-areas and the first buses  115 . The second leads  118  are connected to the N-areas and the second buses  116 . The first buses  115  and the second buses  116  are further connected to an external driving circuit (not shown). 
     The black matrix  113  covers the infrared detection layer  114 , the first buses  115 , the second buses  116 , the first leads  117 , and the second leads  118 . The black matrix  113  is configured to absorb light beams passing therethrough and keep the color units separate from each other. 
     The light beams generator  140  includes a first button  141  configured to control emission of visible light beams, a second button  142  configured to control emission of infrared light beams, and a convex lens  143  configured to focus the visible light beams and the infrared light beams emitting therefrom. By using the convex lens  143 , an area irradiated by the visible light beams and the infrared light beams can be controlled to be less than that of one single display unit  132 . In operation, the visible light beams are configured to show an irradiated position of the liquid crystal display  100 , and the infrared light beams are configured to irradiate the shown position for remote control. In the illustrated embodiment, the light beams generator  140  is a light-generating pen. 
     For convenience, a Decare coordinate system is induced to describe an operation of the remote control display system  10 . The Decare coordinate system includes an X-axis parallel to the second buses  116 , and a Y-axis parallel to the first buses  115 . That is, the first bus  115  connected to the irradiated P-area has a defined X-coordinate, and the second bus  116  connected to the irradiated N-area has a defined Y-coordinate. When the first button  141  is pressed, the visible light beams are generated and focused by the convex lens  143 . When the P-area and the N-area of the infrared detection layer  114  are irradiated, photogenic charge carriers are generated and result in a measurable voltage. A voltage applied to the first bus  115  connected to the irradiated P-area via the first lead  117  rises, and a voltage applied to the second bus  116  connected to the irradiated N-area via the second lead  118  correspondingly drops. Therefore, the X-coordinate and the Y-coordinate of the irradiated position of the infrared detection layer  114  can be thus determined, and is sent to the external driving circuit via the first and second buses  115 ,  116 . With the determined information of the irradiated position, the external driving circuit can generate correspondingly control signals. 
     In summary, the visible light beams are generated and irradiate the infrared detection layer  114  to provide a visual guide before the infrared light beams irradiate the infrared detection layer  114 , which can provide a reliable remote control. Moreover, there is no need of a touch panel employed in the remote control display system  10 , which may provide a light liquid crystal display  100  and avoid use of adhesive. 
     Referring to  FIG. 4  and  FIG. 5 , a remote control display system  20  according to a second embodiment of the present disclosure is shown. The remote control display system  20  is similar to the remote control display system  10  of the first embodiment except a color filter substrate  210  of a liquid crystal display  200  thereof. The color filter substrate  210  includes a glass substrate  211 , a color filter layer  212 , a first infrared detection layer  214   a , a second infrared detection layer  214   b , a plurality of first buses  215 , a plurality of second buses  216 , a plurality of third buses  217 , and a plurality of fourth buses  218 . The color filter layer  210  includes a plurality of red, green, and blue color units (not labeled) regularly arranged at the glass substrate  211 . The first infrared detection layer  214   a  covers portions of the glass substrate  211  extending along a first direction between the color units. The second infrared detection layer  214   b  covers portions of the glass substrate  211  extending along a second direction orthogonal to the first direction between the color units. Each of the first infrared detection layer  214   a  and the second infrared detection layer  214   b  includes a plurality of P-areas and N-areas. An insulate layer (not shown) is arranged between each cross portion of the first and second infrared detection layers  214   a ,  214   b.    
     Terminals of the first infrared detection layer  214   a  are connected to the first buses  215  and the second buses  216 , respectively. Terminals of the second infrared detection layer  214   b  are connected to the third buses  217  and the fourth buses  218 , respectively. The first buses  215  and the third buses  217  are connected to the P-areas of the first and second infrared detection layers  214   a ,  214   b . The second buses  216  and the fourth buses  218  are connected to the N-areas of the first and second infrared detection layers  214   a ,  214   b . The first, second, third and fourth buses  215 ,  216 ,  217 ,  218  are connected to an external driving circuit (not shown). The color filter substrate  210  further includes a black matrix layer  213  covers the first and second infrared detection layer  214   a ,  214   b.    
     The remote control display system  20  can be operated similar to the remote control display system  10 . For convenience, a Decare coordinate system is induced to describe an operation of the remote control display system  20 . When the color filter substrate  210  is irradiated by infrared light beams, a first coordinate is defined by the first infrared detection layer  214   b , and a second coordinate is defined by the second infrared detection layer  214   b . A voltage difference between the first and second infrared detection layers  214   a ,  214   b  is thus generated, and is sent to the external driving circuit. Therefore, the irradiated position of the liquid crystal display  200  can be determined. With the determined information of the irradiated position, the external driving circuit can generate correspondingly control signals. The remote control display system  20  can achieve advantages similar to those of the remote control display system  10 . 
     Further or alternative embodiments may include the following. In one example, the visible light beams not only irradiate the liquid crystal display  100  to provide a visual guide before the infrared light beams irradiate the infrared detection layer  114 , but also irradiate the liquid crystal display  100  to identify the irradiated position after the infrared light beams irradiate the infrared detection layer  114 . Therefore, an improved accurate control of the remote control display system  10  can be achieved. In another example, the area irradiated by the visible light beams and the infrared light beams of the infrared detection layer  114  is greater than that of one single display unit  132 . 
     It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit or scope of the disclosure or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the disclosure.