Patent Publication Number: US-2005122279-A1

Title: Method of warming up a display device

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a method of warming up a display device and, more particularly, to a method of warming up a display device without inputting a test signal.  
      2. Description of the Related Art  
      Both cathode-ray tube (CRTs) displays and liquid crystal displays (LCDs) need to perform a warming up process for quality examination during manufacture, to ensure that each displayer can display an image pattern precisely. The color saturation of the display image pattern will be stable after a warming up period (for example, 20 minutes), and then a technician performs a modification of display parameters to correct the color of the display image pattern. Since different display devices have different structures, they require different warming up methods.  
      As shown in  FIG. 1 , a CRT display device  10  has a power button  12  and a plurality of adjustment buttons on a front panel; the power button  12  is used for turning the cathode-ray tube  10  on or off, and the plurality of adjustment buttons  14  are used for calling up an on screen display (OSD) interface to adjust the display parameters.  
      As shown in  FIG. 2 , a video signal input interface  21  of the CRT display device  10  is used for inputting an image signal and outputting the image signal to a microprocessor  22  and an OSD controller  25  respectively. A memory  23  is used for storing display parameters, and the microprocessor  22  generates an image pattern according to the display parameters and the image signal, and utilizes a synchronous process chip  24 , a vertical deflection controller  27 , a horizontal deflection controller  28  and a display driver  29  to drive the cathode-ray tube for displaying the image pattern on the screen. The OSD controller  25  is triggered by the adjustment buttons  14  and utilizes an amplifier  26  to output an OSD signal to the display driver  29  so as to display the OSD interface on the screen. When the CRT display device  10  is to perform a warming up process, the CRT display device  10  inputs the image signal to generate the image pattern; if the video signal input interface  21  does not input any image signal, the CRT display device  10  switches into a power-saving mode, such as idle mode or sleep mode, and will cease the warming up process.  
      As shown in  FIG. 3 , a video signal input interface  31  of an LCD display device  30  inputs the image signal and outputs the image signal to a microprocessor  32  and a scalar  34  respectively. A memory  33  is used for storing display parameters, and the microprocessor  22  generates an image pattern according to the display parameters and the image signal, and utilizes the scalar  34  and a display driver  35  to drive a display panel to display the image pattern. When the LCD display device  30  is to perform a warming up process, the video signal input interface  31  inputs the image signal to generate the image pattern; if the video signal input interface  31  did not input the image signal, the LCD display device  30  will switch into a power-saving mode, such as idle mode or sleep mode, and will cease the warming up process.  
      Therefore, both display devices require an image signal to be input into the video signal input interface  21  or  31  to generate the image pattern to perform the warming up process. During the manufacturing step for either of the display devices, only a few images output devices (such as computer) are available. If every display device must be connected to the image output devices for 20 minutes, a great deal of time is wasted.  
      Therefore, it is desirable to provide a method of warming up a display device to mitigate and/or obviate the aforementioned problems.  
     SUMMARY OF THE INVENTION  
      A main objective of the present invention is to provide a method of warming up a display device so that the display device can perform a warm up process without an image signal.  
      Another objective of the present invention is to provide a method of warming up a display device, which avoids long warm up time that otherwise reduce the lifetime of the display device.  
      In order to achieve the above-mentioned objectives, there is at least one adjustment button placed on the display device, the at least one adjustment button is used for calling up a visual adjusting display interface and setting a display parameter, the method comprises: (A) turning on the display device; (B) determining if the at least one button is pressed; if the at least one button is not pressed, step (F) is next performed; (C) determining if an image signal is input; if there is no image signal input, step (E) is next performed; (D) utilizing a display driving circuit to output an image to a display device, and then performing step (C); and (E) calling the visual adjusting display interface to set up a display parameter corresponding to the image; wherein the image is output by a visual adjusting display control center, the image signal is provided by an image output device, and the display device driving circuit is used for driving the display device to display the image.  
      Another method of the present invention comprises: (A) switching on the display device; (B) determining if the at least one button is pressed; if the at least one button is not pressed, the method is ceased; and (C) outputting an image to a display driving circuit; wherein the image is output by a visual adjusting display control center, and the display driving circuit is used for driving the display device to display the image.  
      Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a schematic drawing of a CRT display device;  
       FIG. 2  is a functional block drawing of the CRT display device;  
       FIG. 3  is a functional block drawing of a liquid crystal display; and  
       FIG. 4  is a flowchart of the method of warming up the display device according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      The method of warming up the display device (either the CRT display device  10  or the LCD display device  30 ) according to the present invention requires no input image signal; the OSD controller  25  or the image dimension processor  34  outputs the image signal automatically according to an instruction from the microprocessor  22  or  32 , and then the driving circuit  29  or  35  drives the cathode-ray tube or the display panel to display an image pattern. Since the display device displays the image pattern according to the image signal, the display device performs the warming up process. In the present invention, the warming up process can be initiated by appropriate pressing of one of the adjustment buttons  14 ; for example, by continuously pressing one of the adjustment buttons  14  for 5 seconds, or by pressing two or more adjustment buttons  14  at the same time, so that the microprocessor  22  or  32  will be triggered and then the display device will perform the warming up process. Therefore, the method of warming up the display device not only saves on warming up time, but also saves on the manufacturing costs of the image output device. The method of warming up the display device comprises the following steps:  
      Step S 40 : initializing. After the display device is turned on, the user decides whether the display device should perform the warming up process or switch to the power-saving mode.  
      Step S 41 : determining whether an adjustment button  14  is pressed; if the user presses at least one adjustment button  14 , the microprocessor  22  or  32  will output an instruction to perform the warming up process; otherwise, the display device will enter into the normal mode and step S 45  is performed. During the warming up process, the OSD controller  25  or the image dimension processor  34  generates an image signal automatically according to the command from the microprocessor  22  or  32 , and then the screen or the display panel will display the image pattern corresponding to the image signal. In the normal mode, when the image output device outputs the image signal, the display device generates the image pattern corresponding to the image signal; if the image output device does not output an image signal, the display device will switch into the power-saving mode to save the power. The switching process, however, is not the purpose of the present invention, and so no further description will be provided.  
      Step S 42 : determining whether an image signal is input. The image output device outputs the image signal to the display device so that the display device displays the image pattern. When the image output device outputs the image signal to the display device, step S 44  is performed next; otherwise, step S 43  is next performed.  
      Step S 43 : outputting the image signal automatically to perform the warming up process. Since the triggered microprocessor  22  or  32  outputs the instruction the OSD controller  25  or the scalar  34 , the image pattern driven by the driving circuit  29  or  35  corresponds to the image signal and is displayed on the screen or the display panel. The image pattern can be a red block, a blue block, a green block, a white block or a combination of the above blocks. The image pattern also can change its position, shape, or color with time, and then step S 42  is re-performed.  
      Step S 44 : modifying and saving the display parameters. When the image output device outputs the image signal to the display device, the display device performs the warming up process for a period and the color saturation becomes more and more stable, so the technician modifies the display parameters precisely and saves the modified display parameters in the memory  23  or  33  via the OSD interface. The display parameters include image color, image position, image size and so on.  
      Step S 45 : end.  
      Another embodiment to warm up a display is also applicable to execute the above steps of the first embodiment in addition to the steps S 42  and S 44 , so that this second embodiment has only steps S 40 , S 41 , S 43  and S 45 . The only difference between the two embodiments is whether the display parameters are provided for adjustment; when the display device manufacturer needs no more additional display parameter adjustment, the second embodiment is preferable.  
      Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.