Abstract:
A portable terminal is provided including a touch screen display; and a processor configured to control the touch screen display to display a brightness step selection interface for selecting a brightness step, receive, via the touch screen display, a first user input for selecting a first brightness step, control the touch screen display to display an indicator at a first position corresponding to the first brightness step and to control a brightness of the touch screen display based on the first brightness step, receive, via the touch screen display, a second user input for selecting a second brightness step, and control the touch screen display to change a position of the indicator from the first position to a second position corresponding to the second brightness step and to change the brightness of the touch screen display based on the second brightness step.

Description:
[0001]    This application is a continuation of U.S. patent application Ser. No. 13/243,497, which was filed in the U.S. Patent and Trademark Office on Sep. 23, 2011, which is a continuation of U.S. patent application Ser. No. 11/340,617, which was filed in the U.S. Patent and Trademark Office on Jan. 27, 2006, issued as U.S. Pat. No. 9,318,074 on Apr. 19, 2016, and claims priority under 35 U.S.C. §119(a) to Korean Patent Application Serial No. 10-2005-0049300, which was filed in the Korean Intellectual Property Office on Jun. 9, 2005, the entire disclosure of each of which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a portable terminal. More particularly, the present invention relates to a portable terminal capable of controlling a backlight and a method for controlling a backlight thereof. 
         [0004]    2. Description of the Related Art 
         [0005]    A conventional portable terminal having a backlight function turns on and off the backlight at a predetermined level of brightness for a period of time which is set by a user. Therefore, a user can operate the portable terminal containing the backlight function at night while using a lower illumination intensity. 
         [0006]    The portable terminal can be programmed to set the on time of the backlight. Namely, in the case in which a user sets the on time of the backlight to thirty seconds, the portable terminal turns the backlight on for thirty seconds when the power is turned on or there are key input data, and the backlight is turned off after thirty seconds. 
         [0007]    The backlight is generally turned on at a candela value of a predetermined brightness that is determined during the manufacturing process of the portable terminal. If a backlight of a predetermined brightness is turned on at night, however, the battery is unnecessarily consumed. Due to the low exterior illumination intensity at night, a user can see the display screen even with a backlight of a low brightness. 
         [0008]    On the other hand, a user having a weak visual acuity may feel that the brightness of the fixed or predetermined backlight is too dark when the user uses the portable terminal at night with a low illumination intensity. In this case, if the brightness of the backlight can be made brighter, the user can operate the portable terminal more conveniently. 
         [0009]    A need therefore exists for an improved portable terminal wherein the backlight can be controlled to reduce battery consumption or to better suit the needs of users requiring more backlight brightness than is provided by the initial manufacturers setting. 
       SUMMARY 
       [0010]    Accordingly, the present invention has been made to address the above-mentioned problems, and an aspect of the present invention is to provide a portable terminal and a method for controlling a backlight. 
         [0011]    It is another aspect of the present invention to provide a method for reducing battery consumption in a portable terminal having a backlight function. 
         [0012]    In accordance with an aspect of the present invention, a portable terminal is provided for controlling a display brightness thereof. The portable terminal includes a touch screen display; and a processor configured to control the touch screen display to display a brightness step selection interface for selecting one of a plurality of brightness steps, receive, via the touch screen display, a first user input for selecting a first brightness step of the plurality of brightness steps, control the touch screen display to display an indicator at a first position corresponding to the first brightness step and to control a brightness of the touch screen display based on the first brightness step, receive, via the touch screen display, a second user input for selecting a second brightness step of the plurality of brightness steps, and control the touch screen display to change a position of the indicator from the first position to a second position corresponding to the second brightness step and to change the brightness of the touch screen display based on the second brightness step. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The above and other objects, features, and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: 
           [0014]      FIG. 1  is a block diagram illustrating a portable terminal according to an exemplary embodiment of the present invention; 
           [0015]      FIG. 2  is a flow chart illustrating the operation of a portable terminal according to an exemplary embodiment of the present invention; 
           [0016]      FIG. 3  is a flow chart illustrating the operation of a portable terminal according to an exemplary embodiment of the present invention; 
           [0017]      FIGS. 4A and 4B  are exemplary views illustrating the operation of a portable terminal according to an exemplary embodiment of the present invention. 
       
    
    
       [0018]    Throughout the drawings, like reference numerals will be understood to refer to like parts, components and structures. 
       DETAILED DESCRIPTION OF EMBODIMENTS 
       [0019]    Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein is omitted for clarity and conciseness. 
         [0020]      FIG. 1  is a block diagram illustrating a portable terminal according to an exemplary embodiment of the present invention. 
         [0021]    The portable terminal  100  comprises a radio transceiver  110 , a modem  120 , an audio processing unit  130 , a key input unit  140 , a memory  150 , a control unit  160 , a backlight regulating unit  165 , a camera module  170 , an image processing unit  180 , and a display unit  190 . 
         [0022]    The radio transceiver  110  transmits and receives voice data, letter data, image data, and control data, under the control of the control unit  160 . The radio transceiver  110  comprises a RF transmitter for raising and amplifying the frequencies of transmitted signals and an RF receiver for amplifying received signals with low noise and lowering the frequencies. 
         [0023]    The modem  120  comprises a transmitter for encoding and modulating the transmitted signals and a receiver for decoding and demodulating the received signals. 
         [0024]    The audio processing unit  130  can comprise a codec. The codec comprises a data codec for processing packet data and the like and an audio codec for processing audio signals such as voices and the like. 
         [0025]    The audio processing unit  130  modulates the electrical signals input from a microphone and converts them to voice data, and demodulates the encoded voice data input from the radio transceiver  110  into electrical signals and outputs them to a speaker. Further, it is preferable that the audio processing unit  130  comprises a codec to convert the digital audio signals received by the radio transceiver  110  to analog signals and then reproduce them, or to convert the analog audio signals generated in the microphone to digital audio signals. The codec comprises a data codec for processing packet data and an audio codec for processing audio signals such as voices. The codec can be provided in the control unit  160 . 
         [0026]    The key input unit  140  has a key matrix structure (not shown), and comprises letter keys, number keys, function keys, and exterior volume keys to output the key input signals corresponding to the keys input by a user to the control unit  160 . 
         [0027]    The memory  150  can comprise a program memory and a data memory, and stores selected information on the basis of the information required for controlling the operation of the portable terminal  100  according to an exemplary embodiment of the present invention and the user selecting information. The memory  150  stores the backlight brightness values corresponding to the backlight steps, such as, the number and amount of incremental increases and correspondingly decreases in brightness level of a backlight that are generally preset during manufacturing of a portable terminal according to an exemplary embodiment of the present invention. The backlight brightness values preferably correspond to candela values (unit: cd) representing luminosity. 
         [0028]    It is preferable that the memory  150  stores the backlight brightness values corresponding to the backlight steps as shown in the following Table 1 wherein an exemplary number of steps=5. 
         [0000]    
       
         
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                   
                 TABLE 1 
               
             
             
               
                   
                   
               
               
                   
                 Backlight steps 
               
             
          
           
               
                   
                 1 
                 2 
                 3 
                 4 
                 5 
               
               
                   
                   
               
             
          
           
               
                   
                 Candela 
                 100 
                 125 
                 150 
                 175 
                 200 
               
               
                   
                 values (cd) 
               
               
                   
                   
               
             
          
         
       
     
         [0029]    Referring to Table 1, the backlight steps comprise five steps, and a candela value of 100 cd corresponds to the step  1  of the backlight, a candela value of 125 cd corresponds to the step  2  of the backlight, a candela value of 150 cd corresponds to the step  3  of the backlight, a candela value of 175 cd corresponds to the step  4  of the backlight, and a candela value of 200 cd corresponds to the step  5  of the backlight. Referring to Table 1, it can be seen that the backlight brightness is the brightest in step  5  and the candela value corresponding to the step  5  is the highest. On the other hand, although the backlight steps are divided into five steps in an exemplary embodiment of the present invention, they are not restricted thereto and can be divided into more or fewer steps. 
         [0030]    On the other hand, the memory  150  can store the information in which predetermined keys correspond to the backlight steps having predetermined backlight brightness values as shown in the following Table 2. 
         [0000]    
       
         
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                 TABLE 2 
               
             
             
               
                   
                   
               
               
                   
                 Backlight steps 
               
             
          
           
               
                   
                   
                   
                   
                   
                 5 
               
               
                   
                 1 (100 cd) 
                 2 (125 cd) 
                 3 (150 cd) 
                 4 (175 cd) 
                 (200 cd) 
               
               
                   
                   
               
             
          
           
               
                 Corresponding 
                 Number 
                 Number 
                 Number 
                 Number 
                 Number 
               
               
                 Keys 
                 key 1 
                 key 2 
                 key 3 
                 key 4 
                 key 5 
               
               
                   
               
             
          
         
       
     
         [0031]    Referring to Table 2, the backlight steps are divided into five steps, and the backlight step  1  whose candela value is 100 cd corresponds to the number key  1 , the backlight step  2  whose candela value is 125 cd corresponds to the number key  2 , the backlight step  3  whose candela value is 150 cd corresponds to the number key  3 , the backlight step  4  whose candela value is 175 cd corresponds to the number key  4 , and the backlight step  5  whose candela value is 200 cd corresponds to the number key  5 . 
         [0032]    Referring to Table 2, the backlight brightness is the brightest in step  5 , and it is preferable that the numbers allocated to the number keys indicate the backlight steps. Although the backlight steps are divided into five steps in Table 2, they are not restricted thereto and can be divided into more or fewer steps. 
         [0033]    The control unit  160  controls the overall operation of the portable terminal  100  according to an exemplary embodiment of the present invention. The control unit  160  stores in the memory  150  the predetermined backlight brightness values, that is, the candela values corresponding to the backlight steps. Further, the control unit  160  associates the predetermined keys, for example, the number keys, to the backlight steps having the backlight brightness values, and then stores them in the memory  150 . Then, it is preferable that the control unit  160  controls the portable terminal so that the numbers allocated to the number keys correspond to the backlight steps. 
         [0034]    If regulation of the backlight is requested by the user, the control unit  160  converts the operation mode of the portable terminal  100  to the backlight regulation mode and controls the brightness of the backlight by retrieving the backlight brightness values stored in the memory  150  so as to correspond to the backlight steps required by the user through the key input unit  140  in the backlight regulation mode. It is preferable that after converting the operation mode of the portable terminal  100  to the backlight regulation mode, the control unit  160  controls the portable terminal so that the display unit  190  displays a step selecting screen for selecting the backlight step by a user. 
         [0035]    On the other hand, if one of the predetermined keys, for example, one of the number keys, stored in Table 2 is input, the control unit  160  can control the brightness of the backlight in the backlight step corresponding to the input key in the backlight regulation mode. In other words, if the user inputs the number key  5  through the key input unit  140  in the backlight regulation mode, the brightness of the backlight is regulated to the brightness of the step  5  by the control unit  160 . 
         [0036]    It is preferable that the control unit  160  controls the portable terminal so that at least one of the currently regulated backlight steps and the backlight brightness values is displayed on the display unit  190  in order that the user can easily recognize the currently regulated backlight brightness. 
         [0037]    The backlight regulating unit  165  regulates the backlight brightness of the display unit  190  according to the backlight brightness value output by the control unit  160 . The backlight regulating unit  165  can be included in the control unit  160 . 
         [0038]    In the case in which the portable terminal  100  has a camera function, it can comprise the camera module  170 . 
         [0039]    The camera module  170  can comprise a lens unit (not shown) which can be inserted and withdrawn, and photographs image data. 
         [0040]    Further, the camera module  170  comprises a camera sensor (not shown) for converting the photographed optical signals into electrical signals and a signal processing unit (not shown) for converting the analog image signals photographed by the camera sensor to digital data. 
         [0041]    Here, the camera sensor is assumed to be a Charge Coupled Device (CCD) sensor, and the signal processing unit can be embodied with a Digital Signal Processor (DSP). The camera sensor and the signal processing unit can be embodied integrally or separately. 
         [0042]    The image processing unit  180  generates screen data for displaying the image signals output in the camera module  170 . 
         [0043]    The image processing unit  180  processes the image signals output in the camera module  170  in frame unit and outputs the frame image data according to the characteristics and size of the display unit  190 . Further, the image processing unit  180  comprises an image codec. The image processing unit  180  compresses the frame image data shown on the display unit  190  or restores the compressed frame image data to the original frame image data. 
         [0044]    Further, the image processing unit  180  is assumed to have an On Screen Display (OSD) function and can output the OSD data according to the size of the screen displayed under the control of the control unit  160 . 
         [0045]    The display unit  190  can comprise a Liquid Crystal Display (LCD) and the like and outputs the display data generated in the portable terminal. Then, if the LCD is the touch screen type, the display unit  190  can be used as an input unit. 
         [0046]    Further, the display unit  190  displays the image signals output in the image processing unit  180  and displays the user data output in the control unit  160 . 
         [0047]    Further, it is preferable that the display unit  190  comprise white light emitting diodes for the backlight function, and according to an exemplary embodiment of the present invention, the light emitting diodes are assumed to emit the light in the brightness of 150 cd to perform the backlight function unless they are otherwise adjusted by the user. 
         [0048]      FIG. 2  is a flow chart illustrating the operation of the portable terminal according to an exemplary embodiment of the present invention. 
         [0049]    Referring to  FIGS. 1 and 2 , the control unit  160  matches the preset backlight brightness values to the backlight steps and stores them in the memory  150 . It is preferable that when the control unit  160  associates the preset backlight brightness values to associated backlight steps and stores them in the memory  150  at step S 110 , they are stored in a table as in Table 1. 
         [0050]    The control unit  160  examines whether there is a request for backlight regulation by the user, for example, a request through menu key input by the user. On the other hand, in an exemplary embodiment of the present invention, the backlight means the screen backlight brightness of the display unit  190  at step S 120 . 
         [0051]    The control unit  160  converts the operation mode of the portable terminal  100  to the backlight regulation mode if there is the request for the backlight regulation at step S 130 . 
         [0052]    If the operation mode of the portable terminal  100  is converted to the backlight regulation mode, the control unit  160  displays the backlight step selection screen for selecting a backlight step on the display unit  190  at step S 140 . 
         [0053]    The control unit  160  checks whether a backlight step is selected on the basis of the selection information of the user at step S 150 . 
         [0054]    If a backlight step is selected on the basis of the selection information of the user, the control unit  160  detects the brightness value corresponding to the selected backlight step from the memory  150  at step S 160 . 
         [0055]    The control unit  160  regulates the backlight brightness of the display unit  190  by controlling the backlight regulating unit  165  according to the retrieved backlight brightness value at step S 170 . Then, the control unit  160  can display the backlight step or the brightness value on the display unit so that the user can easily recognize the currently regulated backlight brightness. 
         [0056]      FIG. 3  is a flow chart illustrating the operation of a portable terminal according to an exemplary embodiment of the present invention. 
         [0057]    Referring to  FIGS. 1 and 3 , the control unit  160  assigns predetermined keys (for example, number keys) to the backlight steps having predetermined backlight brightness values and stores them in the memory  150  at step S 210 . Then, it is preferable that the numbers allocated to the number keys indicate the backlight steps. 
         [0058]    The control unit  160  examines whether there is a request for the backlight regulation of the user, for example, a request through menu key input of the user at step S 220 . 
         [0059]    If there is a request for backlight regulation, the control unit  160  converts the operation mode of the portable terminal  100  to the backlight regulation mode at step S 230 . 
         [0060]    The control unit  160  determines whether the number keys, such as the number keys registered in Table 2, stored in the memory are input through the key input unit  140  at step S 240 . 
         [0061]    If one of the number keys registered in Table 2 is input, the control unit  160  retrieves from memory the backlight brightness value of the backlight step corresponding to the input number key at step S 250 . For example, if the number key  5  to which the step  5  is allocated is input through the key input unit  140 , the backlight brightness is regulated to the backlight brightness value that corresponds to the step  5 . 
         [0062]    The control unit  160  regulates the backlight brightness of the display unit  190  by controlling the backlight regulating unit  165  according to the detected backlight brightness value at step S 260 . Then, the control unit  160  can display the backlight step or the brightness value on the display unit so that the user can easily recognize the currently regulated backlight brightness. 
         [0063]      FIGS. 4Aa and 4B  are exemplary views illustrating the operation of a portable terminal according to an exemplary embodiment of the present invention. 
         [0064]    Hereinafter,  FIGS. 4A and 4B  will be explained with reference to  FIGS. 1 to 3 . 
         [0065]      FIG. 4A  shows a screen for requesting for backlight regulation of the portable terminal by a user. 
         [0066]    If the user selects the “4. illumination brightness regulation” menu item in the screen of  FIG. 4A  through a direction key or other input and inputs the confirmation key, the portable terminal shows a screen for regulating the illumination brightness as shown in  FIG. 4B . 
         [0067]    In  FIG. 4B , the backlight regulation steps comprise total five steps, and selection flags are provided in the front of the items representing the steps respectively so that the selected item can be checked whenever the backlight step is selected. In  FIG. 4B , the user has selected the step  5 . 
         [0068]    On the other hand, it is preferable that the backlight of the display unit  190  is regulated to the brightness corresponding to the step selected by the user so that the user can recognize the backlight brightness corresponding to each step. 
         [0069]    According to an exemplary embodiment of the present invention, the user can properly regulate the backlight of the portable terminal  100  according to the situation, and can reduce the consumption of the battery due to the user of the backlight of unnecessary brightness. 
         [0070]    Although exemplary embodiments of the present invention describe the backlight brightness regulation of the display unit of the portable terminal, the present invention can be applied to the backlight regulation of a keypad. Further, while the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. 
         [0071]    As mentioned above, the present invention can properly regulate the backlight brightness of a portable terminal, if necessary, by providing a portable terminal controlling the backlight and a method for controlling the backlight. 
         [0072]    Further, since the present invention can regulate the backlight brightness at night so that the illumination intensity is low, battery consumption can be reduced.