Patent Publication Number: US-2006015282-A1

Title: System and method for testing a display device

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to systems and methods for testing electronic products, and particularly to a system and method for testing display devices.  
      2. General Background  
      Display devices, such as Liquid Crystal Displays, Plasma Display Panels, etc., generally undergo a final testing process. For example, testing is done in order to determine whether the image quality of the display device is satisfactory for launching of the device into the market. The testing items of a display device typically include brightness, chrominance, contrast, etc. Each of these testing items needs to be carefully tested to evaluate the image quality.  
      A traditional testing process mainly requires an operator to manually manipulate setting buttons on a panel of a display device. The operator switches among testing items such as brightness, chrominance, and contrast, in order to determine one by one whether each of the items has met standard requirements. This manual testing process may be unduly time-consuming and waste valuable manpower, especially in the case of mass production of the display devices.  
      What is needed, therefore, is a system and method for testing display devices, which is capable of automatically testing the display devices in order to overcome the above-mentioned problems.  
     SUMMARY OF THE INVENTION  
      To solve the above mentioned and other problems, a display device testing system (hereinafter “the system”) is provided. The system includes a video signal outputting apparatus, a remote controller, a back board and a display devices which needs to be tested. The video outputting apparatus outputs video signals to the display device. The video signals contain one or more testing samples provided for testing the display device. The remote controller generates control signals to control the display device to display the testing samples. The back board includes an interface, for example, the back board configured with a VGA ((video graphic array) interface or a DVI ((digital visual interface) interface. The interface receives the control signals from the controller, combines the control signals with video signals containing one or more testing samples into mixed signals, and transmits the mixed signals to the display device to obtain a test result. The control signals and the video signals are combined into mixed signals by means of pins of the interface. For example, the control signals and the video signals are combined via 12 th  and 15 th  pins of the VGA or via 6 th  and 7 th  pins of the DVI. The mixed signals are output to the display device so that the display device displays test samples and obtains the test result according to the mixed signals. The test result is sent back to the remote controller via the back board for evaluating the performances of the display device.  
      Further, a display device testing method is also provided. The method includes: (a) providing video signals containing one or more testing samples via a video signal outputting apparatus; (b) generating and transmitting control signals containing instructions to control the display device to display the testing samples in correspondence to one or more testing items preset by an operator; (c) receiving and combining the control signals with the video signals containing a testing sample to obtaining combined signals, wherein the control signals and the video signals are combined via pins of a video signal output interface; (d) transmitting the combined signals to the display device; (e) displaying the testing sample and obtaining a test result of the testing items; and (f) evaluating the test result of the display device.  
      Other advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a block diagram showing hardware infrastructure of a system for testing display devices according to a preferred embodiment of the invention; and  
       FIG. 2  is a flowchart showing a preferred method for testing a display device according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       FIG. 1  is a block diagram of hardware infrastructure of a system for testing a display device  40  (hereinafter “the testing system”) according to a preferred embodiment of the present invention. The testing system mainly includes a video signal outputting apparatus  10 , a remote controller  20 , and a back board  30 . The video outputting apparatus  10  is a computer or any other suitable apparatus, which is adapted for outputting video signals to the display device  40 . The video signals contain one or more testing samples provided for testing the display device  40 . The remote controller  20  preferably includes a computer  210  and a first wireless transmission apparatus  220 . The computer  210  and the first wireless transmission apparatus  220  are interconnected with each other via a COM (Communication) port or an LTP (Print Port) port of the computer  210 .  
      The computer  210  communicates with the display device  40  via the back board  30  and the first wireless transmission apparatus  220 . The computer  210  is utilized to generate and transmit control signals. The control signals generally contain example instructions for controlling the display device to display given testing samples in correspondence to testing items set by an operator, and for displaying an analysis result to the operator. The computer  210  is also utilized to analyze obtained test result data of the display device  40 . For example, once it receives the test result data from the back board  30 , the computer  210  compares the test result data with standard reference data that are pre-stored in the computer  210 . The computer  210  analyzes the test result data to generate an analysis result to determine whether the display device  40  is qualified, and then displays the test result data and the analysis result to the operator. For example, if the display device  40  fails to meet a standard requirement on a given testing item according to a corresponding analysis result, the computer  210  then displays the test result data and the analysis result to the operator.  
      The first wireless transmission apparatus  220  includes a transmitter and a receiver. The first wireless transmission apparatus  220  is interconnected with the back board  30  by a wireless connection. Wireless signals transmitted between the first wireless transmission apparatus  220  and the back board  30  can be in a form of infrared waves, microwaves, or ultrasonic waves. In another exemplary embodiment, the remote controller  20  may consist of only a first wireless transmission apparatus  220  to transmit or receive the wireless signals. In the absence of the computer  210 , the first wireless transmission apparatus  220  further includes a built-in micro-programmed control unit (MCU) (not shown), a display unit (not shown), and a plurality of operational buttons (not shown). The MCU, the display unit and the operational buttons cooperatively allow an operator to preset testing items, and analyze obtained test result data. Likewise, once receiving the test result data from the back board  30 , the MCU compares the test result data with standard reference data that are pre-stored in the MCU, analyzes the test result data to generate an analysis result in order to determine whether the display device  40  is qualified, and displays the test result data and the analysis result to the operator. For example, if the display device  40  fails to meet a standard requirement on a testing item according to a corresponding analysis result, the MCU then controls the display unit to display the test result data and the analysis result to the operator. In the preferred embodiment of the present invention, the remote controller  20  controls the testing of the display device  40  by way of the wireless signals transmitted between the first wireless transmission apparatus  220  and the back board  30 .  
      The back board  30  is utilized to mix up the control signals from the remote controller  20  with the video signals from the video signal outputting apparatus  10 , and to thereby generate mixed signals. The back board includes a VGA (video graphic array) interface  310  and a second wireless transmission apparatus  320 . The second wireless transmission apparatus  320  is similar to the first wireless transmission apparatus  220 . The first and second wireless transmission apparatuses  220 ,  320  intercommunicate with each other by the wireless connection.  
      The VGA interface  310  is generally a 15-pin VGA interface. The VGA interface  310  has a 12 th  pin used as an SDA (serial data line) and a 15 th  pin used as an SCL (serial clock line). By means of the 12 th  and 15 th  pins, the control signals and the video signals are combined with each other, and the mixed signals are obtained. The mixed signals containing the control signals and the video signals are then transmitted in a common VGA cable. In an alternative embodiment, a DVI (digital visual interface) interface may be employed as a substitute for the VGA interface  310 . The DVI interface serves as a communication channel between the video outputting apparatus  10  and the display device  40 . The control signals and the video signals are combined into mixed signals via 6 th  and 7 th  pins of the DVI interface. The mixed signals are then transmitted to the display device  40 .  
      The display device  40  mainly includes a display controller  410  and a display circuit  420 . The display controller  410  generally includes an MCU. The display controller  410  is used to control the display circuit  420  to display the testing samples and thereby obtaining the test result data on each testing item that is preset by the operator, as described above. The test result data are then sent back to the remote controller  20  via the back board  30 , for evaluating the performance of the display device  40 .  
       FIG. 2  is a flowchart of a preferred method for testing display devices according to the present invention. The method includes the following steps. In step S 200 , an operator presets testing items via the remote controller  20 . In step S 210 , the video signal outputting apparatus  10  transmits video signals containing one or more testing samples to the display device  40  via an interface of the back board  30 . In the illustrated embodiment, the interface can be a VGA interface  310  or a DVI interface that is configured in the back board  30 . In step S 220 , the remote controller  20  transmits a control signal containing the testing items preset by the operator to the back board  30 . In step S 230 , the back board  30  mixes up the control signal with the video signals via pins of the interface  310 , generates a mixed signal accordingly, and then outputs the mixed signal to the display device  40 . In step S 240 , the display device  40  displays the testing samples, and obtains the test result data on the testing items preset by the operator. The test result data are then transmitted back to the remote controller  20  via the back board  30 . In step S 250 , the remote controller  20  analyzes the test result data by comparing the test result data with standard reference data to determine whether the display device  40  is qualified based on the analysis result. In step S 260 , the remote controller  20  displays the analysis result and the test result data to the operator.  
      Although the present invention has been specifically described on the basis of preferred embodiments and a preferred method, the invention is not to be construed as being limited thereto. Various changes and modifications may be made to the embodiments and method without departing from the scope and the spirit of the invention.