Patent Publication Number: US-2010122102-A1

Title: Display device and method for displaying power consumption

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from Korean Patent Application No. 10-2008-0110475, filed Nov. 7, 2008, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Devices and methods consistent with the present invention relate to a display device and method for displaying power consumption information, and more particularly, to a display device and method for displaying power consumption information of the display device in a current display mode. 
     2. Description of the Related Art 
     As electronic technology has been developing, various kinds of home appliances have been used. Examples of the home appliances include display devices such as televisions. Recently, the screens of display devices, such as liquid crystal displays (LCD) and plasma display panels (PDP), have become bigger, resulting in increased power consumption of the television units compared with cathode-ray tube televisions. 
     Accordingly, users may wish to know how much power their big screen display devices consume. 
     Generally, a label showing power consumption is attached to display devices, but such a label only shows the maximum power consumption and does not show variation in power consumption according to the usage. 
     Furthermore, since power consumption used by the components of the display device is not shown, the user does not know how much power a specific component consumes. 
     Therefore, there is a need to determine how much power the components of the display device consume. 
     SUMMARY OF THE INVENTION 
     Exemplary embodiments of the present invention address at least the above problems and/or disadvantages and other disadvantages not described above. Also, the present invention is not required to overcome the disadvantages described above, and an exemplary embodiment of the present invention may not overcome any of the problems described above. 
     Exemplary embodiments of the present invention provide a display device and method for calculating and displaying power consumption using a software-oriented method. 
     According to an exemplary aspect of the present invention, there is provided a display device including a user input unit, a calculation unit which calculates power consumption in a current display mode if a user command to display the power consumption is input through the user input unit, and a display unit which displays information regarding the power consumption calculated by the calculation unit. 
     The calculation unit may individually calculate and sum up power consumption of each component used to output a broadcast so as to calculate a total power consumption of the display device. 
     The calculation unit may individually calculate power consumption of each component used to output a broadcast, and the display unit may additionally display the individually calculated power consumption of each component. 
     The calculation unit may individually calculate power consumption of each component used to output a broadcast, and the display unit may additionally display power consumption of a component selected by a user from among the individually calculated power consumption of each component. 
     The display device may further include a storage unit which stores information regarding power consumption of other components previously calculated by a user. 
     The calculation unit may calculate power consumption of a sound component using an audio output value set in the current display mode, calculate power consumption of a backlight unit using dimming information corresponding to a video output value set in the current display mode, and sum up the calculated power consumption of the sound component and backlight unit and the power consumption of the other components stored in the storage unit so as to calculate the power consumption in the current display mode. 
     The storage unit may store individually stores the power consumption of each component calculated by the calculation unit, or store the sum of the power consumption of each component calculated by the calculation unit. 
     The calculation unit may calculate the power consumption of the sound component E(vol) using the following equation: E(vol)=E(sound)*A(vol_set)/A(vol_max), wherein E(sound) indicates a maximum output power of the sound component, A(vol_max) indicates a maximum volume, and A(vol_set) indicates a volume set by the user. 
     The calculation unit may calculate the power consumption of the backlight unit E(dim) using the following equation: E(dim)=E(blu)*A(dim_set)/A(dim_max), wherein E(blu) indicates a maximum output power of the backlight unit, A(dim_max) indicates a maximum dimming value, and A(dim_set) indicates a dimming value set by a user. 
     The display mode may be a mode in which a broadcast is output according to an audio output value and a video output value which are individually set by a user. 
     The display mode may be one of a day mode, a night mode, a clear screen mode, a soft screen mode, a standard screen mode, a movie screen mode, and a news screen mode. 
     According to another exemplary aspect of the present invention, there is provided a method for displaying power consumption of a display device, the method including outputting a broadcast according to a preset audio output value and a preset video output value, calculating power consumption in a current display mode, in which the broadcast is output according to the preset audio output value and the preset video output value, if a user command to display the power consumption is input, and displaying information regarding the calculated power consumption. 
     The calculating operation may include individually calculating and summing up power consumption of each component used to output the broadcast so as to calculate a total power consumption of the display device. 
     The method may further include additionally displaying individually calculated power consumption of each component used to output the broadcast. 
     The method may further include additionally displaying individually calculated power consumption of a component selected by a user from among components used to output the broadcast. 
     The calculating operation may include calculating power consumption of a sound component using an audio output value set in the current display mode, calculates power consumption of a backlight unit using dimming information corresponding to a video output value set in the current display mode, and summing up the calculated power consumption of the sound component and backlight unit and pre-stored power consumption of other components so as to calculate the power consumption in the current display mode. 
     The method may further include individually storing calculated power consumption of each component, or storing the sum of calculated power consumption of each component. 
     The calculating operation may include calculating the power consumption of the sound component E(vol) using the following equation: E(vol)=E(sound)*A(vol_set)/A(vol_max), wherein E(sound) indicates a maximum output power of the sound component, A(vol_max) indicates a maximum volume, and A(vol_set) indicates a volume set by a user. 
     The calculating operation may include calculating the power consumption of the backlight unit E(dim) using the following equation: E(dim)=E(blu)*A(dim_set)/A(dim_max), wherein E(blu) indicates a maximum output power of the backlight unit, A(dim_max) indicates a maximum dimming value, and A(dim_set) indicates a dimming value set by a user. 
     The display mode may be one of a day mode, a night mode, a clear screen mode, a soft screen mode, a standard screen mode, a movie screen mode, and a news screen mode. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and/or other aspects of the present invention will be more apparent by describing certain exemplary embodiments of the present invention with reference to the accompanying drawings, in which: 
         FIG. 1  is a schematic block diagram of a display device according to an exemplary embodiment of the present invention; 
         FIG. 2  is a detailed block diagram of the display device according to an exemplary embodiment of the present invention; 
         FIG. 3  illustrates an example of displaying power consumption information in the display device according to an exemplary embodiment of the present invention; 
         FIG. 4  illustrates an example of displaying power consumption information in the display device according to an exemplary embodiment of the present invention; 
         FIG. 5  illustrates an example of displaying power consumption information in the display device according to an exemplary embodiment of the present invention; 
         FIG. 6  is a flow chart illustrating a method for displaying power consumption information in the display device according to an exemplary embodiment of the present invention; and 
         FIG. 7  is a flow chart illustrating a method for calculating power consumption values according to an exemplary embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Exemplary embodiments of the present invention are described in greater detail below with reference to the accompanying drawings. 
     In the following description, like drawing reference numerals are used for like elements, even in different drawings. The matters defined in the description, such as detailed construction and elements, are provided to assist in a comprehensive understanding of the invention. However, the present invention can be practiced without those specifically defined matters. Also, well-known functions or constructions are not described in detail since they would obscure the invention with unnecessary detail. 
       FIG. 1  is a schematic block diagram of a display device  102  according to an exemplary embodiment of the present invention. As illustrated in  FIG. 1 , the display device  102  may include a user input unit  110 , a calculation unit  120 , and a display unit  130 . 
     The user input unit  110  inputs a user command to display power consumption information. More specifically, a user may input a command to display power consumption information by manipulating a key pad provided on a main body of the display device or manipulating a remote controller. Alternatively, the user input unit  110  may be implemented as a touch screen. In this case, an on-screen display (OSD) menu to input a command to display power consumption information is displayed on the screen of the display device. When a user touches the OSD menu, the user input unit  110  recognizes that the user command to display power consumption information is input. 
     The calculation unit  120  calculates a power consumption value in a current display mode if a user command to display power consumption information is input. For example, a display mode is a mode in which an output state is defined according to an audio output value set by the user, that is, a volume value, or a video output value set by the user. A video output value indicates a value regarding various video information, such as the luminance, contrast, chroma, and brightness, which is set by the user. 
     For example, a display mode is a mode in which an audio output value and a video output value set as the default are applied. For example, the display device may operate in various display modes such as a day mode, a night mode, a clear screen mode, a soft screen mode, a standard screen mode, a movie screen mode, and a news screen mode. A mode of the display device is converted according to selection by the user. Audio and video are output as an audio output value and a video output value defined in the selected mode. 
     The calculation unit  120  calculates power consumption values of individual components used to output a broadcast signal. More specifically, the display device may use a board in which various circuits used to process a broadcast signal are integrated. Examples of such circuits or components include a sound component which outputs an audio signal from a processed broadcast signal, a panel which outputs a video signal from a processed broadcast signal, a backlight unit which provides the luminance needed to output a video signal, and the like. The total power consumption value of the display device is the sum of respective power consumption values of such components. Accordingly, the calculation unit  120  calculates the total power consumption value by separately calculating a power consumption value of each component and summing up the calculated power consumption values. 
     The power consumption of the board and the panel does not vary to great extent even if the user sets an audio output value or a video output value to be great values. Accordingly, the power consumption value of the board and the panel (referred to hereinafter as the “power consumption value of other components”) may be calculated in advance under a particular experimental condition, pre-stored, and repeatedly used in further calculations. 
     The power consumption value of other components may be calculated as: 
         E (board)= E (total)− E (blu_set)−E(sound_set)   (1) 
     In Equation 1, E(board) indicates the power consumption value of other components, E(total) indicates the total power consumption value under the experimental condition, E(blu_set) indicates the power consumption value of the backlight unit under the experimental condition, and E(sound_set) indicates the power consumption value of the sound component under the experimental condition. 
     That is, for calculation, output values of the backlight unit and the sound component as, for example, an amplifier or a speaker, may be set to be equal to particular power values. For example, the output power of the backlight unit is fixed to 100 W, and the output power of the sound component is fixed to 1 W. Under this condition, the total power consumption value E(total) of the display device can be calculated by directly measuring the electric current flowing into the display device and the voltage applied to the display device as P=V×I. 
     Consequently, the power consumption value of other components E(board) can be calculated by subtracting the power values 100 W and 1 W from the total power consumption value E(total). In this case, since the output value of the sound component is negligible, the output value of the sound component may be omitted. 
     The power consumption value of other components E(board) which is calculated using the above method is pre-stored in a storage unit  140 . 
     The setting state of an audio output value affects the power consumption of the sound component, and the setting state of a video output value affects the power consumption of the backlight unit. 
     Therefore, the calculation unit  120  may calculate the power consumption value of the sound component as: 
         E (vol)= E (sound)* A (vol_set)/ A (vol_max)   (2) 
     In Equation 2, the sound component power consumption value E(sound) indicates the maximum output power of the sound component, A(vol_max) indicates the maximum audio output value, and A(vol_set) indicates the audio output value set by the user. 
     The power consumption of the sound component varies according to an audio output value set by the user. The power consumption value of the sound component at the maximum level may be provided by a manufacturer. The power consumption value of the sound component at various levels can be obtained using Equation 2 based on proportional relationship. For example, if it is assumed that the maximum audio output value of the sound component is level 50, the power consumption value at level 50 is 80 W. If level 20 is set by the user in the current display mode, the power consumption value of the sound component in the current display mode is calculated as approximately 80*20/50=32 W. 
     In addition, the calculation unit  120  may calculate the power consumption value of the backlight unit as: 
         E (dim)= E (blu)* A (dim_set)/ A (dim_max)   (3) 
     In Equation 3, the power consumption value of the backlight unit E(blu) indicates the maximum output power of backlight unit, A(dim_max) indicates the maximum dimming value, and A(dim_set) indicates the dimming value set by the user. 
     As described above, a video output value is determined according to various video factors such as the luminance, the chroma, the contrast, and the brightness. Accordingly, a luminance value, that is, a dimming value of the backlight unit is determined by summing up the video factor values. Obtaining a dimming value from video factor values may be performed using one of known algorithms. For example, if a dimming value ranges from 0 to 255, the maximum dimming value A(dim_max) is 255. It is assumed that if a dimming value is 255, an output power value of the backlight unit is 200 W. If the current dimming value is 100, E(dim) is calculated as approximately 200*10/255=78.4 W. 
     The calculation unit  120  calculates the total power consumption value by adding the power consumption values of the components, calculated using Equations 2 and 3 and the pre-stored power consumption value of other components. The total power consumption value may be obtained as: 
         E (final)= E (board)+ E (vol)+ E (dim)   (4) 
     In the above example, if the power consumption value of other components is 60 W, the total power consumption value is approximately 60+32+78.4=170.4 W. 
     The display unit  130  displays information regarding the power consumption value calculated by the calculation unit  120  on the screen. In this case, the information may be displayed in an OSD method. 
       FIG. 2  is a detailed block diagram of the display device  102  according to an exemplary embodiment of the present invention. 
     As illustrated in  FIG. 2 , the display device  102  may include an user input unit  110 , a calculation unit  120 , a display unit  130 , a storage unit  140 , a tuner unit  150 , a multiplexer  160 , a video signal processing unit  170 , a backlight control unit  175 , a backlight unit  180 , an audio signal processing unit  185 , and an amplifier  190 . 
     The tuner unit  150  is tuned to a broadcast channel and receives a broadcast signal. 
     The multiplexer  160  divides the broadcast signal received by the tuner unit  150  into a video signal and an audio signal. If the broadcast signal includes a data signal, the data signal is also divided by the multiplexer  160 . In this case, the display device may further include a data signal processing unit. 
     The video signal divided by the multiplexer  160  is transmitted to the video signal processing unit  170 . The video signal processing unit  170  decodes, interleaves, deinterleaves, and scales the video signal to convert the video signal into a displayable format. For example, the video signal processing unit  170  processes the video signal to have the luminance, the brightness, the chroma, and the contrast corresponding to a video output value preset by the user. 
     The display unit  130  receives the video signal processed by the video signal processing unit  170 , and displays the video signal on the screen. The display unit  130  may include a display panel  132  and a display control unit  131 . The display panel  132  may be implemented as an LCD. The display control unit  131  controls the liquid crystal cells of the display panel  132  according to the video signal to express an image. 
     The video signal processing unit  170  calculates a dimming value corresponding to the video output value preset by the user, and provides the backlight control unit  175  with the dimming value. The backlight control unit  175  drives the backlight unit  180  to have the luminance corresponding to the dimming value. 
     The audio signal processing unit  185  decodes, interleaves, and deinterleaves an audio signal received from the multiplexer  160  to restore audio data. The restored audio data are transmitted to the amplifier  190 . The amplifier  190  amplifies the audio data to have a gain corresponding to an audio output value set by the user, and outputs the audio data. 
     The storage unit  140  stores the audio output value and the video output value which are set by the user in the current display mode. The storage unit  140  also stores information regarding previously measured power consumption value of other components. The storage unit  140  also stores information regarding a fixed display mode having an audio output value and a video output value which are defined as the default by a manufacturer or the user. That is, the manufacturer or the user may experimentally measure video factors and the sound volume suitable for viewing according to various content categories including movies, news, drama, etc., and set an audio output value and a video output value as the default using the measured values. Alternatively, the manufacturer or the user may set values suitable for viewing according to the time zone such as day or night, or set a display mode to express clearly or softly according to the screen characteristics. As described above, if various display modes are set as the default, the user can set a display mode suitable for currently viewing content, a viewing time, and the user&#39;s preference by selecting a conversion button. 
     Although a single storage unit is illustrated in  FIG. 2 , the storage unit  140  may be implemented as at least one non-volatile memory and at least one volatile memory. In this case, the information described above is stored in appropriate memory. 
     The calculation unit  120  calculates power consumption values of the components as described above. In  FIG. 2 , the calculation unit  120  calculates the power consumption value of the backlight unit  180  and the power consumption value of the amplifier  190  using Equation 3 and Equation 2, respectively. The power consumption value of other components remains nearly constant regardless of a display mode, and thus can be calculated using Equation 1 and pre-stored. 
     If the display mode is set as the default, the storage unit  140  may store the power consumption value which is previously calculated for each display mode. In this case, the power consumption value stored in the storage unit  140  is read out and displayed without being calculated whenever a display mode changes. 
     In addition, the storage unit  140  may store the total power consumption value obtained by summing up the power consumption values of the components, and separately store the power consumption value of each component. Accordingly, the display unit  140  may display the power consumption value of each component as well as the total power consumption value. In this case, the display unit  140  may selectively display the power consumption values of components which the user wishes to know. The user may input desired information through the user input unit  110  using a key on the remote controller. 
     The user input unit  110  receives a user command to display power consumption information, and other user commands as described with reference to  FIG. 1 . Detailed description of the same components as those in  FIG. 1  is not repeated here. 
       FIGS. 3 ,  4 , and  5  illustrate examples of displaying information regarding power consumption in the display device according to an exemplary embodiment of the present invention. 
     In  FIG. 3 , only the total power consumption value  10  is displayed on one side of the screen  100  as an OSD. In this case, the screen  100  can keep displaying currently viewing content. 
     In  FIG. 4 , the total power consumption value  10  is displayed on one side of the screen  100 . The power consumption values of the components  20  are displayed underneath the total power consumption value  10 . In  FIG. 4 , the power consumption values of the backlight unit, the sound component, the panel, and the circuit are displayed. However, the power consumption values of the panel and the circuit do not substantially change, and thus can be grouped as one category and displayed as 60 W. 
     As illustrated in  FIG. 5 , the total power consumption value  10  is displayed. The power consumption values of only selected components  30  which the user wishes to know are displayed underneath the total power consumption value. 
     The process of displaying the power consumption value of the components can be performed in various manners. For example, if the user inputs a command to display power consumption information, the display device displays the total power consumption value as illustrated in  FIG. 3 , and activates a menu to select whether to display the power consumption values of the components thereunder. If the user selects to display the power consumption values of selected components, the display device displays the power consumption values of the selected components. 
       FIG. 6  is a flow chart illustrating a method for displaying power consumption information in the display device according to an exemplary embodiment of the present invention. 
     As illustrated in  FIG. 6 , if a broadcast signal is being output (S 610 ), and a user command to display power consumption information is input (S 620 ), a current display mode is identified (S 630 ). Identifying the current display mode indicates identifying a setting state of a currently output image characteristics, that is, a video output value, and a setting state of a currently output sound volume, that is, an audio output value. Alternatively, identifying the current display mode indicates identifying which display mode is selected from among fixed display modes and identifying a video output value and an audio output value in the selected display mode. 
     Subsequently, the power consumption information corresponding to the current display mode is calculated (S 640 ). Since a method for calculating the power consumption information has been described above in detail with reference to  FIG. 1 , description is not repeated here. 
     Information regarding the calculated power consumption is displayed on the screen (S 650 ). 
     According to exemplary embodiments of the present invention, the display device may display information regarding only the total power consumption, display information regarding the power consumption of each component as well as the total power consumption, or display information regarding only the power consumption of each component. In addition, the power consumption values of only selected components of which the user wishes to know the power consumption information, may be displayed with the total power consumption information or separately from the total power consumption information. 
     Following the above process, the user can identify the power consumption value of the display device in the current display mode set by the user. Furthermore, the process illustrated in  FIG. 6  may be performed using software-oriented calculation, so additional hardware might not be needed. 
       FIG. 7  is a flow chart illustrating an example of a process of calculating power consumption values according to an exemplary embodiment of the present invention. 
     As illustrated in  FIG. 7 , a setting state of an audio output value and a video output value of a currently displayed broadcast is identified (S 710 ). More specifically, the volume set by the user or a dimming value according to video factor values set by the user are identified. 
     Subsequently, the power consumption value of each component is individually calculated using the identified setting values (S 720 ). More specifically, the setting values of the sound component and the backlight unit are individually calculated using Equation 2 and Equation 3, respectively. 
     Pre-stored information regarding the power consumption value of other components is read out (S 730 ), and then is added to the calculated power consumption value. The total power consumption value of the display device is calculated (S 740 ). 
     As described above, since the power consumption of each component of the display device can be identified, the user can maintain the power consumption of each component at the minimum level, and set and view the desired screen, thereby enabling the optimum screen setting. 
     In the exemplary embodiments of the present invention, a method for displaying power consumption information when a broadcast signal is being output is described. However, the present invention is not limited to a broadcast signal. The inventive concept can be applied even when a signal provided from a recording medium playback device such as a digital versatile disk (DVD) player is being processed. In this case, the tuner unit  150  illustrated in  FIG. 2  can be omitted as a component. 
     In addition, in the exemplary embodiments of the present invention, the display device is not limited to a television, but may be implemented as a monitor, a laptop computer, or an electronic picture frame. 
     The foregoing exemplary embodiments and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. Also, the description of the exemplary embodiments of the present invention is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art.