Abstract:
A display includes a display panel, a transflective reflector positioned on a lower surface of the display panel, an upper polarizer positioned on the upper surface of the display panel, a lower polarizer positioned on the lower surface of the transflective reflector, and a backlight unit positioned below the lower polarizer. The transflective reflector partially reflects light propagating to the transflective reflector so as to improve images of the display.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The invention relates to a display, and more particularly, to a display with a transflective reflector.  
         [0003]     2. Description of the Prior Art  
         [0004]     As the technology advances, mobile information devices have been fully utilized in our daily lives. Flat panel displays used in the mobile information devices, therefore, had become important. Because of their advantages of light weight, low power consumption, and no radiation, flat panel displays have been widely applied in notebooks, personal digital assistants (PDAs), cellular phones, and similar mobile information devices, and become to take large market shares in the market of consuming electronics.  
         [0005]     Since the mobile information devices must meet the requirements of the market such as light weight, small size, and low power consumption, the flat panel displays applied on these devices must have continuous developments to produce good images with low power consumption and thin thickness. Currently the industry proposed to reutilize the ambient light so that the displays may have the function of micro-reflection, which allows the display to produce clear images by micro-reflecting ambient light even though the back light module is off. Most of the manufacturers now form thin reflective layers during the fabrication process of the internal elements on the glass substrate of the display panels for creating the effects of micro-reflection. For example, in the manufacturing processes of thin film transistors (TFTs), such as micro filming or etching processes, reserving some reflective metal conducting layers in each individual pixel area may improve the brightness and quality of the images on the screen, since the metal conducting layers may micro-reflect the ambient light. However, this method complicates the original manufacturing processes and may reduce the yield rate.  
       SUMMARY OF THE INVENTION  
       [0006]     It is therefore a primary objective of the claimed invention to provide a display with a transflective reflector positioned on the lower surface of the display panel for partially reflecting ambient light to increase the brightness of displayed images and solve the above-mentioned problems.  
         [0007]     According to the claimed invention, the display comprises a display panel, a transflective reflector positioned on the lower surface of the display panel, an upper polarizer on the upper surface of the display panel, a lower polarizer on the lower surface of the transflective reflector, and a backlight module under the lower side of the polarizer to provide the back light source for the display panel.  
         [0008]     In the claimed invention, since a transflective reflector is positioned between the display panel and a polarizer, partial ambient light may be reflected back by the transflective reflector to the display panel to increase the brightness of the displayed images and also to decrease the utilization and power consumption of the backlight module.  
         [0009]     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a cross-section schematic diagram of a display according to a first embodiment of this invention.  
         [0011]      FIG. 2  is a schematic diagram of a frontal view of the transflective reflector in  FIG. 1 .  
         [0012]      FIG. 3  and  FIG. 4  are the cross-section schematic diagrams of displays according to a second and a third embodiment of this invention respectively.  
         [0013]      FIGS. 5-7  are cross-section schematic diagrams of displays according to a forth embodiment, a fifth embodiment and a sixth embodiment of this invention respectively. 
     
    
     DETAILED DESCRIPTION  
       [0014]     Please refer to  FIG. 1 .  FIG. 1  is a cross-section schematic diagram of a display  10  according to a first embodiment of this invention. The display  10  comprises a display panel  12  and a backlight module  14  positioned under the display panel  12 . The display panel  12  is a liquid crystal display (LCD) panel. An upper polarizer  16  is on the upper surface of the display panel  12  and a lower polarizer  18  is on the lower surface of the display panel. Between the lower polarizer  18  and the display panel  12  is a transflective reflector  24 . The upper polarizer  16  and the transflective reflector  24  are attached to two sides of the display panel  12  through an upper adhesive  20  and a lower adhesive  22  respectively.  
         [0015]     Please refer to  FIG. 2 .  FIG. 2  is a schematic diagram of a frontal view of the transflective reflector  24  in  FIG. 1 . The transflective reflector  24  is a transparent thin plate which comprises a plurality of reflective patterns  26  on its surfaces. Therefore, light passing through the display panel  12  and reaching the reflective patterns  24  may be completely reflected by the reflective patterns  24  and back into the display panel  12  to be reutilized to improve the brightness of the display images, as the arrows indicate. In addition, the portion of surface of the transflective reflector  24  without the reflective patterns  26  is the light-penetrating region  28  which allows light to propagate and continue forward. Hence the rate of penetration and the rate of reflection of the transflective reflector  24  are determined by the ratio of the area of the reflective patterns  26  to the area of the transflective reflector  24 . Moreover, the reflective patterns  26  may be composed by reflective semi-transparent materials, such as photoresist materials or metal thin films. The surfaces of the reflective patterns  26  may be selectively roughened to increase the scattering of the reflected light. Or the reflective patterns  26  themselves may be the rough surfaces f the transparent thin plate to create the effects of reflection and diffusion of light.  
         [0016]     In preferable embodiments, the reflective patterns  26  are arranged in an array, as shown in  FIG. 2 , to create an even reflective rate on the entire transflective reflector. In addition, in more preferable embodiments, the reflective patterns  26  are set to evenly corresponding to each pixel or sub-pixel of the display panel  12 . For example, each sub-pixel may include a reflective pattern  26  to ensure light is reflected in each pixel and increase the brightness of the entire display panel  12 . However, the transflective reflector  24  in this invention is not limited to the form that depends on the area of reflective patterns  26 . It may be other thin plates which partially reflect light and allow some light to propagate, such as a semi-transparent panel.  
         [0017]     Please refer to  FIGS. 3-4 .  FIGS. 3-4  are cross-section schematic diagrams of displays according to a second and a third embodiment of this invention respectively. All symbols of parts here are the same as in  FIG. 1 . In the second embodiment, the lower adhesive  22  is a scattering adhesive which comprises a plurality of diffusion particles  30  spread in the lower adhesive  22 . The diffusion particles  30  are made of materials with functions of scattering or reflecting light. When light from the display panel  12  is transmitted into the lower adhesive  22  and reaches the diffusion particles  30  and the transflective reflector  24 , it may be reflected and scattered back to the display panel  12 , as the arrows indicate. Since the distribution density, size, shape, material, and arrangement position of diffusion particles  30  may influence the performance of light scattering, the variables of the diffusion particles  30  as mentioned previously may be different due to the differences of their arrangement positions and of the displays they are applied to. For example, in different arrangement positions in the lower adhesive  22 , the distribution densities of the diffusion particles  30  may be completely different. The display  10  shown in  FIG. 4  also comprises a lower retardation film  32  and an upper retardation film  34  in the inner side of the lower polarizer  18  and the upper polarizer  16  respectively to recover the problem of chromatic polarization resulting from the process of reflection and diffusion of light.  
         [0018]     Referring to  FIG. 5 ,  FIG. 5  is a cross-section schematic diagram of a display according to a forth embodiment of this invention. The display  50  comprises a display panel  52  and a backlight module  54 . On the upper surface and lower surface of the display panel  50  are an upper polarizer  56  and a lower polarizer  58  respectively which are attached to the surfaces of the display panel  52  via an upper adhesive  60  and a lower adhesive  62  separately. In addition, on the lower surface of the lower polarizer  58  is a transflective reflector  64  which may be the same as the transflective reflector  24  as in  FIG. 2  or other thin plates with the function of partially reflecting light.  
         [0019]      FIGS. 6-7  are cross-section schematic diagrams of displays according to a fifth and a sixth embodiment of this invention respectively.  FIG. 6  shows a plurality of diffusion particles  66  are distributed in the lower adhesive  62  to enhance the diffusion of light and adjust the path of the reflected light. The embodiment in  FIG. 7  has an upper retardation film  68  between the upper polarizer  56  and the display panel  52  and a lower retardation film  70  between the lower polarizer  58  and the display panel  52 . Since the scatter and reflection of light may create problems of chromatic polarization and weaken the intensity of light with certain wavelengths, the upper and lower retardation films  68 ,  70  for certain wavelengths may be provided to improve the display images.  
         [0020]     In contrast to the prior art, this invention provides a transflective reflector on the lower surface of the display panel to improve the brightness of the entire display images by partially reflecting light from external ambient light sources passing into the display panel. Furthermore, since the transflective reflector may reflect ambient light, the goal of reducing power consumption may be reached because the user may still see clear images on the display while the backlight source is off or light source with relatively low brightness is provided by the backlight module. In addition, since the transifective reflector in this invention uses reflective patterns to create the function of reflecting light, its rate of reflection and rate of penetration may be adjusted easily by changing the area and the shape of the reflective patterns, so that better displays may be designed by utilizing simple manufacturing processes and methods.  
         [0021]     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.