Abstract:
A brightness controlling system includes a sensor, an input device, a display device and a control circuit. The sensor is used for detecting a current ambient illumination level. The input device is used for inputting brightness adjusting commands. The control circuit is used for receiving the brightness adjusting commands and sending control signals to the display device to adjust a current brightness value based on the brightness adjusting commands, and updating relationships between ambient illumination levels and brightness values according to the brightness adjusting commands. A related brightness controlling method and a storage medium recorded with an application program to accomplish the brightness controlling method are also provided.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention generally relates to systems and methods for controlling display devices brightness and, more particularly, to a brightness controlling system and method for automatically adjusting the brightness of a display device.  
       DESCRIPTION OF RELATED ART  
       [0002]     Display devices, such as cathode ray tube (CRT) monitors and liquid crystal display (LCD) screens, are wildly used in people&#39;s everyday life. The display devices are used in computers, mobile phones, and other electronic apparatuses to display text or graphic information.  
         [0003]     Display devices, especially those used in portable electronic apparatuses, such as notebook computers, are usually taken to various locations. Ambient illuminations of the locations may be different. If the display devices maintain a constant brightness regardless of the ambient illuminations change, the brightness may not be suitable to the ambient illuminations. This will make viewers feel uncomfortable.  
         [0004]     Traditionally, special functional keys are provided on the display devices for adjusting the brightness of the display device according to viewing comfortableness and the ambient illuminations thereof. However, manual adjustment is not convenient and, particularly substantially impossible to follow the change of ambient illuminations. Thus it is desirable to change the brightness of the display device automatically according to the ambient illuminations.  
         [0005]     Therefore, automatic adjustments of the brightness of the display devices based on the ambient illuminations have been introduced. A sensor is provided in the display device for detecting a current ambient illumination level and for generating electronic signals based on the current ambient illumination level. The electronic signals are used to change a current brightness value of the display device, so as to conform to the current ambient illumination level.  
         [0006]     However, the above mentioned automatic adjustments of the brightness cannot truly satisfy different viewers&#39; requirements because of different viewers comfortableness. That is, at a given ambient illumination level, a viewer A may prefer a relatively high brightness, while a viewer B may prefer a relatively low brightness. However, the sensor generates only one kind of electronic signal dependant on the specific ambient illumination level. Therefore, only one fixed brightness value can be provided according to the fixed relationships between the brightness values and the ambient illumination levels.  
         [0007]     Therefore, an improved system and method for adjusting the brightness of a display device is desired.  
       SUMMARY OF THE INVENTION  
       [0008]     A brightness controlling system includes a sensor, an input device, a display device and a control circuit. The sensor is used for detecting a current ambient illumination level. The input device is used for inputting brightness adjusting commands. The control circuit is used for receiving the brightness adjusting commands and sending control signals to the display device to adjust a current brightness value based on the brightness adjusting commands, and updating relationships between ambient illumination levels and brightness values according to the brightness adjusting commands.  
         [0009]     A brightness controlling method for controlling brightness of a display device includes steps of: detecting a current ambient illumination level; determining whether a command is inputted for changing current brightness of the display device; changing the current brightness of the display device based on the command if the command is inputted; and updating relationships between brightness values and ambient illumination levels.  
         [0010]     A storage medium is provided for recording an application program. The application program has a computer executable the steps of: detecting a current ambient illumination level; determining whether a command is inputted for changing current brightness of the display device; changing the current brightness of the display device based on the command if the command is inputted; and updating relationships between brightness values and ambient illumination levels.  
         [0011]     Other advantages and novel features will become more apparent from the following detailed description of preferred embodiments when taken in conjunction with the accompanying drawings, in which: 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     Many aspects of the brightness controlling system and the brightness controlling method thereof can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, the emphasis instead being placed upon clearly illustrating the principles of the present device. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.  
         [0013]      FIG. 1  is a block diagram of a brightness controlling system in accordance with an exemplary embodiment; and  
         [0014]      FIG. 2  is a flow chart illustrating a brightness controlling procedure of a brightness controlling method in accordance with an exemplary embodiment. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]     Reference will now be made to the drawings to describe the preferred embodiment of the present brightness controlling system, in detail.  
         [0016]     Referring to  FIG. 1 , a block diagram of a brightness controlling system  100  in accordance with an exemplary embodiment is illustrated. The brightness controlling system  100  includes a sensor  110 , a keyboard  120 , a control circuit  130 , and a display device  140 .  
         [0017]     The sensor  110  is a photosensitive element (e.g., a photoresistor, a photodiode, or a phototransistor) and is coupled to the control circuit  130  for generating electronic signals based on ambient illumination levels. The electronic signals are transmitted to the control circuit  130  to indicate a current ambient illumination level.  
         [0018]     The keyboard  120  is coupled to the control circuit  130  for inputting commands to the control circuit  130 . The control circuit  130  adjusts the brightness of the display device  140  according to the commands.  
         [0019]     The control circuit  130  includes a control module  132  and a storage module  134 . The control module  132  receives the electronic signals generated by the sensor  110  and the commands inputted by the keyboard  120 , and then adjusts the brightness of the display device  140  accordingly. The storage module  134  stores a lookup unit  136  that records relationships between the ambient illumination levels and brightness values of the display device  140 .  
         [0020]     The lookup unit  136  includes a brightness-to-step (B-S) table  137  and a level-to-step (L-S) table  138 . The B-S table  137  defines constant relationships between the brightness values and step values. There is a plurality of different brightness values in the B-S table  137 , each brightness value corresponding to a respective step value.  
         [0021]     The L-S table  138  defines relationships between the ambient illumination levels and step values. Each ambient illumination level corresponds to a respective step value. The step values in the L-S table  138  are replaceable according to the commands inputted by the keyboard  120 .  
         [0022]     The step values are employed to associate the brightness values and the ambient illumination levels in the brightness controlling system  100 . For example, the sensor  110  generates an electronic signal representing a current ambient illumination level. The electronic signal is then fed to the control module  132 . A corresponding step value is obtained in the L-S table  138  according to the electronic signal. A corresponding brightness value is then obtained after being searched from the B-S table  137  according to the corresponding step value. Thus the brightness of the display device  140  can be adjusted automatically according to the current ambient illumination level.  
         [0023]     Viewers can reset current brightness of the display device  140  according to their own comfortableness. The step value corresponding to the current ambient level in the L-S table  138  can be modified to another step value defined in the B-S table  137 . Thus relationships between the ambient illumination levels and the brightness values are adjustable in the lookup unit  136 .  
         [0024]     An exemplary B-S table  137  is shown as follows:  
                                                   Brightness Value   Step Value                           B00   S0           B11   S1           B22   S2           B33   S3           B44   S4           . . .   . . .           BFF   S15                      
 
         [0025]     An exemplary L-S table  138  is shown as follows:  
                                                   Illumination Level   Step Value                           L0   S3           L1   S5           L2   S11           L3   S15                      
 
         [0026]     Preferred embodiments will be described with reference to the B-S table  137  and the L-S table  138 . For example, the ambient illumination level is L 0  according to the electronic signals generated by the sensor  110 . The step value corresponding to the ambient illumination level L 0  is S 3  according to the L-S table  138 . The brightness value B 33  is then obtained from the B-S table  137 , and current brightness of the display device  140  is adjusted according to the brightness value B 33 .  
         [0027]     If a current brightness value, such as B 33 , doesn&#39;t meet a viewer&#39;s comfortableness at the current ambient illumination level, such as L 0 , the viewer can modify the current brightness value via the keyboard  120  to another brightness value defined in the B-S table  137 , such as B 22 . The control module  132  updates the relationships between the illumination levels and the brightness values in the lookup unit  136  based on the viewer&#39;s input. The step value S 2 , which corresponds to the brightness value B 22 , replaces the step value S 3  in the L-S table  138 . Then the L-S table  138  is updated as follows:  
                                                   Illumination Level   Step Value                           L0   S2           L1   S5           L2   S11           L3   S15                      
 
         [0028]     When the ambient illumination level detected by the sensor  110  is L 0 , the step value corresponding to the illumination level L 0  is S 2  according to the updated L-S table  138 . The control module  130  adjusts the current brightness of the display device  140  according to the brightness value B 22 . Thus, the current brightness of the display device  140  meets the viewer&#39;s comfortableness.  
         [0029]     Exemplarily, a predetermined key (not shown) can be employed to turn on/off the sensor  110  so as to turn on/off the brightness controlling system  100 . A delay circuit (not shown) can be introduced to the brightness controlling system  100  for setting the brightness adjusting time intervals.  
         [0030]     Referring also to  FIG. 2 , an exemplary brightness controlling procedure of a brightness controlling method is illustrated. First, in step  201 , the sensor  110  is enabled. There are many ways to enable the sensor  110 , such as pressing the predetermined key or using other input devices to input enabling commands.  
         [0031]     Then in step  202 , the sensor  110  detects the ambient illumination and generates electronic signals representing a current ambient illumination level.  
         [0032]     In step  203 , a determination is made as to whether the current brightness value of the display device  140  corresponds to the current ambient illumination level. If so, the procedure then proceeds to step  205 .  
         [0033]     If in step  203 , it is determined that the current brightness value of the display device  140  doesn&#39;t corresponds to the current ambient illumination level, the control module  130  changes the current brightness value accordingly so as to match the current ambient illumination level (step  204 ).  
         [0034]     In step  205 , The control module  130  concludes whether there is a command inputted via the keyboard  120  to change the current brightness of the display device  140 . If no commands are inputted via the keyboard  120  to change the brightness, the procedure delays a period of predetermined time (step  209 ) and loops back to step  202 . If there is a command inputted via the keyboard  120  to change the current brightness, the control module  132  changes the current brightness value according to the command inputted via the keyboard (step  206 ).  
         [0035]     Successively, in step  207 , the control module  132  updates the L-S table  138  of the brightness controlling system  100  by changing the step value that corresponds to the current ambient illumination level in the L-S table  138  to another step value which corresponds to the adjusted brightness value of the B-S table  137 .  
         [0036]     In step  208 , A determination is made as to whether the sensor  110  is disabled. If so, the procedure is terminated. If the sensor  110  is not disabled, the procedure delays a period of predetermined time (step  209 ) and loops back to step  202 .  
         [0037]     When a viewer inputs commands to change the brightness of the display device  140  corresponding to a specific ambient illumination level, the step value will be updated according to the viewer&#39;s input. Thus relationships between the ambient illumination levels and the brightness values are customizable because of an updateable step value.  
         [0038]     The depicted embodiment in  FIG. 1  and the above-described procedure are not meant to imply architectural limitations. It should be noted that the described system is exemplary, and that  FIG. 1  could include any other input devices besides the keyboard  120 , such as, for example, a mouse, predetermined keys set on the display device  140 , touch pad, and the like. It is easy to be understood that the control circuit  130  can be many kinds of controllers or chipsets, such as, but not limited to, an embedded controller, a display controller, a general processor, a graphic processing unit (GPU) or multiple chipsets. The storage module  134  may be a flash memory integrated in the controllers or an independent memory for storing the lookup unit  136  and other program instructions.  
         [0039]     The embodiments described herein are merely illustrative of the principles of the present invention. Other arrangements and advantages may be devised by those skilled in the art without departing from the spirit and scope of the present invention. Accordingly, the present invention should be deemed not to be limited to the above detailed description, but rather by the spirit and scope of the claims that follow, and their equivalents.