Patent Publication Number: US-2010118060-A1

Title: Portable electronic apparatus and method for controlling light thereof

Description:
This application claims the benefit of priority based on Taiwan Patent Application No. 097143393, filed on Nov. 10, 2008, the contents of which are incorporated herein by reference in their entirety. 
     CROSS-REFERENCES TO RELATED APPLICATIONS 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a portable electronic apparatus and a method for controlling light thereof. More particularly, the present invention relates to a portable electronic apparatus having a plurality of sets of light control parameters stored in the memory of a main control module. 
     2. Descriptions of the Related Art 
     Portable electronic apparatuses commercially available in the market, such as mobile phones and personal digital assistants (PDAs), are usually equipped with light-emitting diodes (LEDs) of different colors that can flicker according to different events. For example, when a mobile phone is in a standby mode, a green LED thereof will flicker to indicate that the mobile phone is now in the standby mode. In another example, if the mobile phone operates under a low battery status, a red LED thereof will flicker to remind the user to replace or recharge the battery. However, light control parameters, e.g., the flickering frequency and brightness, dictating the flickering modes of LEDs may have preset and unchangeably stored at memory early in the design stage of a portable electronic apparatus. Therefore, as the number of flickering modes in the portable electronic apparatus increases, the capacity of the memory for storing corresponding light control parameters needs to also be increased accordingly, leading to higher manufacturing costs. 
     Furthermore, as the number of flickering modes increases, it will take more time to find the light control parameters, corresponding to the event occurring, from the memory, making it impossible to adjust the brightness or chromaticity of the LEDs in a real-time manner in response to the event. 
     As a result, it is important to maintain constant memory capacity of the portable electronic apparatus as the number of light control parameters increase while minimizing the time necessary for switching between different light brightnesses of the LED and even while changing from monochromatic light to color light in the portable electronic apparatus. 
     SUMMARY OF THE INVENTION 
     The invention provides a portable electronic apparatus, which comprises a main control module, a light control module and a light source module. The main control module is configured to receive an input signal, and output a first set of light control parameters according to the input signal. The light control module has a first preload unit which is configured to receive and store the first set of light control parameters outputted from the main control module. The light control module generates a light control signal according to the first set of light control parameters. The light source module is electrically connected to the main control module via the light control module and configured to generate light and receive the light control signal to control the brightness of the light. 
     This invention also provides a portable electronic apparatus, which comprises a main control module, a light control module and a light source module. The main control module is configured to output a control signal and a plurality of sets of light control parameters. The light control module has a plurality of preload units which are configured to respectively receive and store the sets of light control parameters outputted from the main control module. The light control module selects one of the sets of light control parameters stored in one of the preload units according to the control signal, and generates a light control signal according to the selected one of sets of the light control parameters. The light source module is electrically connected to the main control module via the light control module and has a first color emitting unit and a second color emitting unit. The light source module is configured to generate a mixing light and receive the light control signal to control the brightness of the mixing light. 
     This invention further provides a method for controlling light of a portable electronic apparatus. The portable electronic apparatus stores a plurality of sets of light control parameters. The method comprises the following steps: receiving an input signal; outputting one of sets of the light control parameters according to the input signal; generating a light control signal according to the outputted one of sets of light control parameters; and controlling the brightness of the light according to the light control signal. 
     According to the above descriptions, the various sets of light control parameters are pre-stored in a memory of the main control module, and the set of light control parameters is transmitted to the light control module for the light control module to generate a light control signal for controlling the light source module. Meanwhile, the present invention further transmits and stores the sets of light control parameters that are frequently used into the preload unit of the light control module. In this way, the capacity of the memory in the light control module is reduced, and the overall time of switching between the brightnesses of the light source module is further shortened. 
     The detailed technology and preferred embodiments implemented for the subject invention are described in the following paragraphs accompanying the appended drawings for people skilled in this field to well appreciate the features of the claimed invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic outside view of the portable electronic apparatus of the present invention; 
         FIG. 2  is a circuit block diagram of the portable electronic apparatus of the present invention; 
         FIG. 3  is a light waveform diagram of the light source module in the portable electronic apparatus of the present invention; 
         FIG. 4  is another schematic outside view of the portable electronic apparatus of the present invention; 
         FIG. 5  is a flowchart illustrating how the portable electronic apparatus of the present invention controls the light brightness; 
         FIG. 6  is a flowchart illustrating how the light control signal is generated; 
         FIG. 7  is a flowchart illustrating how the light brightness is controlled according to the light control signal; and 
         FIG. 8  is a circuit block diagram of another portable electronic apparatus of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the following descriptions, this invention will be explained with reference to the embodiments thereof. However, these embodiments are not intended to limit this invention to any specific environment, applications or particular implementations described in these embodiments. Therefore, descriptions of these embodiments are only for purposes of illustration rather than limitation of this invention. In the following embodiments and the attached drawings, elements unrelated to this invention are omitted from depiction. 
       FIG. 1  shows an outside view of a portable electronic apparatus  3  according to one embodiment of the present invention. The portable electronic apparatus  3  refers generally to apparatuses that are portable in use, including but not limited to mobile phones, notebook computers, personal digital assistants (PDAs), satellite navigation devices and the like. For purposes of illustration, a mobile phone will be described as an example of the portable electronic apparatus  3  in this embodiment. The portable electronic apparatus  3  depicted in  FIG. 1  has an input unit  311  and a light source module  35 . The input unit  311  may be a keypad, a touch screen or some other input device for a user to input instructions. The light source module  35  uses light emitting diodes (LEDs) to generate light, although this invention is not merely limited thereto. 
       FIG. 2  illustrates a circuit block diagram of the portable electronic apparatus  3  of the present invention. The portable electronic apparatus  3  comprises a main control module  31 , a light control module  33  and a light source module  35 . The main control module  31  is electrically connected to an input unit  311  and comprises a memory  313  and a microprocessor  315 . The input unit  311  is adapted to generate an input signal  310  according to an instruction inputted by the user. The memory  313  stores a plurality of sets of light control parameter. For purposes of simplicity, only a first set of light control parameters  3131  and second sets of light control parameters  3133 ,  3135  are illustrated in this embodiment. The microprocessor  315  receives the input signal  310  from the input unit  311  and, after processing the input signal  310 , selects and retrieves light control parameters corresponding to the input signal  310  from the memory  313  for being outputted. In this embodiment, the light control parameters corresponding to the input signal  310  are the first set of light control parameters  3131 . Thus, after receiving the input signal  310 , the microprocessor  315  selects and retrieves the first set of light control parameters  3131  from the memory  313  for being outputted. In other embodiments, the input signal  310  may be generated by other events, for example, an incoming call, a dead battery or an alert event, rather than being limited to be generated by the input unit  311 . 
     The light control module  33  comprises an interface  331 , a control unit  333  and a preload bank  335 . The interface  331  may be an I 2 C bus, a universal serial bus (USB), an IEEE 1394 bus or a serial peripheral interface (SPI). Through the interface  331 , the first set of light control parameters  3131  outputted from the microprocessor  315  of the main control module  31  can be received by the light control module  33 . After receiving the first set of light control parameters  3131 , the control unit  333  generates a light control signal  330  and a preload signal  332  according to the received first set of light control parameters  3131 . The preload bank  335  comprises a first preload unit  335   a  and a second preload unit  335   b . It should be noted that the present invention has no limitation on the number of preload units included in the preload bank  335 , and the two preload units included in the preload bank  335  of this embodiment are only for purposes of illustration rather than limitation of the present invention. 
     After receiving the first set of light control parameters  3131 , the light control module  33  will store it into the first preload unit  335   a . The above description involves operations of the main control module  31  transmitting the first set of light control parameters  3131  to the light control module  33 . However, after the first set of light control parameters  3131  is transmitted to the light control module  33 , the preload signal  332  generated by the light control module  33  will be transmitted to the microprocessor  315  of the main control module  31  so that in response to the preload signal  332 , the microprocessor  315  of the main control module  31  can transmit one of the second sets of light control parameters  3133 ,  3135  from the memory  313  to the light control module  33  and store it into the preload bank  335  via the control unit  333  of the control module  33 . 
     The control unit  333  of the light control module  33  further comprises an access sub-unit  3331 , an executing sub-unit  3333  and an input/output control sub-unit  3335 . The access sub-unit  3331  is configured to receive the aforesaid first set of light control parameters  3131  and generate an access instruction  334  according to the first set of light control parameters  3131 . The executing sub-unit  3333  is configured to execute the access instruction  334  and output a driving signal  336 . The input/output control sub-unit  3335  is configured to receive and process the driving signal  336  and then output the light control signal  330  to the light source module  35 . 
     The light source module  35  consists of a red light emitting unit  351 , a green light emitting unit  353  and a blue light emitting unit  355 . More specifically, each of these light emitting units may be an LED, in which the red LED is adapted to generate red light, the green LED is adapted to generate green light and the blue LED is adapted to generate blue light. The light source module  35  may generate light of a certain brightness level by mixing the light of the aforesaid three primary colors (i.e. red, green, and blue). Each of the aforesaid light control parameter sets  3131 ,  3133 ,  3135  includes red data, green data and blue data. The control unit  333  of the light control module  33  generates the light control signal  330  according to the red, green and blue data of the first set of light control parameters  3131 . Then, the light control signal  330  controls the brightness of the light from the red light emitting unit  351  according to the red data of the first set of light control parameters  3131 , the brightness of the light from the green light emitting unit  353  according to the green data of the first set of light control parameters  3131 , and the brightness of the light from the blue light emitting unit  355  according to the blue data of the first set of light control parameters  3131 . Thus, the brightness of the light from the light source module  35  can be controlled by adjusting the brightness of the red light, the green light and the blue light respectively. 
     More specifically, after the microprocessor  315  of the main control module  31  receives the input signal  310  via the interface  311 , the microprocessor  315  selects and retrieves the first set of light control parameters  3131 , which further comprises a standby mode control parameter, from the memory  313  according to the input signal  310 . The microprocessor  315  then transmits the first set of light control parameters  3131  to the interface  331  of the light control module  33 . The first set of light control parameters  3131  includes red, green and blue data; the configuration of which will be detailed later. After receiving the first set of light control parameters  3131 , the interface  331  then transmits the first set of light control parameters  3131  to the control unit  333  which then programs and stores the red, green and blue data of the first set of light control parameters  3131  into the first preload unit  335   a  respectively. In this embodiment, the first preload unit  335   a  has five pre-configured preload tables  3351 ,  3352 ,  3353 ,  3354  and  3355 . The red, green and blue data of the first set of light control parameters  3131  are stored into the preload table  3351 . Meanwhile, the control unit  333  outputs the light control signal  330  to the light source module  35  so that the light source module  35  can control the brightness of the light according to the first set of light control parameters  3131  (i.e. comprising a standby mode control parameter). 
     While the control unit  333  outputs the light control signal  330  to the light source module  35 , the control unit  333  also transmits the preload signal  332  to the microprocessor  315  of the main control module  31 . In response to the preload signal  332 , the microprocessor  315  transmits the second set of light control parameters  3133  (e.g. comprising an incoming call mode control parameter) or the other second set of light control parameters  3135  (e.g. comprising a dead battery mode control parameter) stored in the memory  313  to the light control module  33 , and stores the red, green and blue data of the second sets of light control parameters  3133 ,  3135  into the preload tables of the second preload unit  335   b  in the aforesaid sequence respectively. Thus, both the second set of light control parameters  3133  (i.e. comprising an incoming call mode control parameter) and the other second set of light control parameters  3135  (i.e. comprising a dead battery mode control parameter) are stored into the second preload unit  335   b  of the light control module  33  in advance. Therefore, when the light source module  35  of the portable electronic apparatus  3  is controlling the brightness of light according to the first set of light control parameters  3131  (i.e. comprising the standby mode control parameter), if there is an incoming call to cause the light source module  35  to be switched to use the second set of light control parameters  3133  (i.e. comprising an incoming call mode control parameter), the control unit  333  may access the red, green and blue data of the second set of light control parameters  3133  directly from the second preload unit  335   b  so that the light brightness of the light source module  35  can be switched promptly to shorten the time necessary for light brightness control. The above embodiment is only provided to illustrate an example of and explain the technical features of this invention, but not to limit the scope of this invention. 
     Herein, it should be appreciated that although the second sets of light control parameters  3133 ,  3135  are stored into the second preload unit  335   b  in this preferred embodiment, the second sets of light control parameters  3133 ,  3135  outputted by the main control module  31  may also be stored into the first preload unit  335   a  apart from the second preload unit  335   b . The present invention does not limit which preload unit of the preload bank  335  the sets of light control parameters will be stored in. That is, the second sets of light control parameters  3133 ,  3135  may be stored into a preload table of either the first preload unit  335   a  or the second preload unit  335   b  according to the preload signal  332 . 
     Additionally, in other embodiments where the portable electronic apparatus  3  has a sliding mechanism or has an extendable and retractable keypad, the first set of light control parameters  3131  stored in the memory  313  is adapted to drive the light source module  35  to generate a flickering light corresponding to the extending action of the keypad, while the second set of light control parameters  313  stored in the memory  313  is adapted to drive the light source module  35  to generate another flickering light corresponding to the retracting action of the keypad. The switching between the brightnesses corresponding to the keypad extending and retracting actions, as well as the operational relationships between the control unit  333  and the preload bank  335  of the light control module  33  and the main control module  31  have been described above and thus will not be further described herein. 
     For modulation of the chromaticity and brightness of the light, the pulse width modulation (PWM) is adopted. Because the PWM is well known in the art, the description of the modulation will be made only briefly herein. 
       FIG. 3  illustrates a brightness waveform diagram of the light source module  35  in the portable electronic apparatus  3  of the present invention. From top to bottom,  FIG. 3  shows a waveform of the red light channel, a waveform of the green light channel and a waveform of the blue light channel of the light source module  35 , respectively. More specifically, for the red light channel, coordinates (x, y) may be used to represent the brightness exhibited by the red light channel at individual time points, in which the horizontal axis (x) represents time and the longitudinal axis (y) represents the brightness exhibited by the red light emitting unit  351  of the light source module  35  through PWM. For example, for an 8-bit system, the red light channel has 256 different color levels, each of which has corresponding brightness. A lower brightness represents a lower color level. In other words, a longitudinal coordinate of 0/256 represents a fully dark state, i.e., a state in which the PWM is completely OFF. On the other hand, a higher brightness represents a higher color level. In other words, a longitudinal coordinate of 256/256 represents a fully bright state, i.e., a state in which the PWM is completely ON. Because the PWM is a conventional technology and those of ordinary skill in the art will readily appreciate how the PWM operates, no further description will be made herein. 
     For example, the red light channel has a brightness value of 0 at the time point 0, the label is (0, 0) which represents a fully dark state of the red light. When the red, green and blue light channels all have a brightness value of 0, the brightness state of the mixed light will be fully dark. At time point x1, the red light channel has a brightness value of 16, so the label is (x1, 16/256), i.e., (x1, 1/16), which represents that the brightness of the red light is one sixteenth of the brightness when the PWM is completely ON. At time point x2, the red light channel has a brightness value of 32, so the label is (x1, 32/256), i.e., (x1, ⅛), which represents that the brightness of the red light is one eighth of the brightness when the PWM is completely ON. The process will continue until the red, green and blue light channels all have their brightness represented by different coordinates (x, y) at different time points. Then, at time point x3, the red light channel, the green light channel and the blue light channel have a brightness value of (x3, 0), (x3, 0) and (x3, 1/16) respectively, so the mixed light is blue with a sixteenth of a brightness thereof when the PWM is completely ON. In this way, the light brightness of the light source module  35  can be controlled, and the chromaticity of the light can also be altered accordingly. 
     Although the operations and actions of only a single light source module  35  are described in this embodiment, this invention has no limitation on the number of light source modules  35 . Operations using a plurality of light source modules  35  (as shown in  FIG. 4 ) will be readily appreciated by those of ordinary skill in the art upon reviewing the above description and thus will not be further described herein. 
     A flowchart of the aforesaid process for controlling light brightness of the light source module  35  in the portable electronic apparatus  3  is depicted in  FIG. 5 . The portable electronic apparatus  3  is adapted to store a plurality of sets of light control parameters, including a first set of light control parameter and at least one second set of light control parameter. However, the number of light control parameters is not limited to three sets, and the three sets of light control parameters of this embodiment are provided only for illustration purposes. The light of the light source module  35  is generated by mixing red light, green light and blue light. The method comprises the following steps. Initially, step S 71  is executed to generate an input signal according to an event. Next, step S 72  is executed to receive the input signal. Then, step S 73  is executed to select and output a first set of light control parameters according to the input signal. 
     Afterwards, step S 74  is executed to receive and store the first set of light control parameters. Step S 75  is executed to generate a light control signal according to the first set of light control parameters. Thereafter, step S 76  is executed to control the brightness of the light according to the light control signal, and step S 77  is executed to generate a preload signal. Finally, step S 78  is executed to update and store at least one second set of light control parameters according to the preload signal. 
       FIG. 6  depicts a flowchart of the process of generating the light control signal in step S 75 . Initially, step S 81  is executed to generate an access instruction according to the first set of light control parameters. Next, step S 82  is executed to execute the access instruction and output a drive signal. Then, step S 83  is executed to receive and process the driving signal. Finally, step S 84  is executed to output a light control signal according to the driving signal. 
       FIG. 7  depicts a flowchart of the process of controlling brightness of the light in step S 76 . Initially, step S 91  is executed to control the brightness of the red light according to the red data of the first set of light control parameters. Next, step S 92  is executed to control brightness of the green light according to the green data of the first set of light control parameters. Finally, step S 93  is executed to control the brightness of the blue light according to the blue data of the first set of light control parameters. 
     In addition to the aforesaid steps, the process of controlling the light brightness of the light source module  35  can also execute all the operations and functions set forth above with respect to the portable electronic apparatus  3  of the present invention. The methods in which the processes of  FIGS. 5-7  execute these operations and functions will be readily appreciated by those of ordinary skill in the art based on the explanation of the portable electronic apparatus  3  of this invention, and thus will not be further described herein. 
     Another preferred embodiment of this invention is depicted in  FIG. 8 , which is another circuit block diagram of the portable electronic apparatus  3  of this invention. The circuit block diagram comprises a main control module  91 , a light control module  93  and a light source module  95 . The main control module  91  comprises a memory  913  and a microprocessor  915 . The memory  913  is configured to store a plurality of sets of light control parameters  9131 ,  9133 ,  9135 . A microprocessor  915  is electrically connected to the memory  913  and configured to select the plurality of sets of light control parameters  9131 ,  9133 ,  9135  from the memory  913  and then output them and a control signal  912  to the light control module  93 . 
     The light control module  93  comprises an interface  931 , a plurality of preload units  935   a ,  935   b  and a control unit  933 . For purposes of simplicity, the plurality of preload units are represented by only a first preload unit  935   a  and a second preload unit  935   b  herein. The aforesaid plurality of sets of light control parameters  9131 ,  9133 ,  9135  are transmitted via the interface  931 , which may be an I 2 C bus, a USB, an IEEE 1394 bus or an SPI. 
     The first preload unit  935   a  and the second preload unit  935   b  receive and store the sets of light control parameters  9131 ,  9133 ,  9135  outputted by the main control module  91  respectively. The light control module  93  is configured to select one of the sets of light control parameters  9131 ,  9133 ,  9135  stored in the first preload unit  935   a  or the second preload unit  935   b  according to the control signal  912  transmitted by the microprocessor  915 . Meanwhile, the light control module  93  generates a light control signal  930  in the control unit  933  according to the selected set of light control parameters. The control unit  933  comprises an access sub-unit  9331 , an executing sub-unit  9333  and an input/output control sub-unit  9335 . After receiving one of sets of light control parameters  9131 ,  9133 ,  9135 , the access sub-unit  9331  generates and transmits an access instruction  934  to the executing sub-unit  9333 . Then, the executing sub-unit  9333  executes the access instruction  934  and outputs a driving signal  936 . The input/output control sub-unit  9335  receives and processes the driving signal  936  and then outputs the light control signal  930  according to the result of processing the processed driving signal  936 . 
     The light source module  95  is electrically connected to the light control module  93  and has a first color emitting unit  951  and a second color emitting unit  955  for generating mixed light. The light source module  95  receives the light control signal  930  and controls the brightness of the mixed light according to the light control signal  930 . It should be noted that the first color emitting unit  951  and second color emitting unit  955  may be LEDs of different colors. For example, the first color emitting unit  951  may be a red LED, while the second color emitting unit  955  may be a blue LED. Alternatively, the first color emitting unit  951  may be a green LED, while the second color emitting unit  955  may be a red LED. 
     This embodiment only makes a slight modification on the internal arrangement of the portable electronic apparatus, with operations of transmitting the sets of light control parameters  9131 ,  9133 ,  9135  among the main control module  91 , the light control module  93  and the light source module  95  as well as functions thereof remaining the same as those in the preferred embodiment shown in  FIG. 2 . Thus, no further description will be made herein. 
     According to the above descriptions, this present invention provides a portable electronic apparatus and a method for controlling light thereof. Furthermore, by storing a plurality of light control parameters into the main control module, and storing selected light control parameters that are used or frequently used into the preload units of the light control module, the necessary capacity of the memory in the light control module is reduced and the adjustment time necessary for controlling the light brightness is further shortened. 
     The above disclosure is related to the detailed technical contents and inventive features thereof. People skilled in this field may proceed with a variety of modifications and replacements based on the disclosures and suggestions of the invention as described without departing from the characteristics thereof. Nevertheless, although such modifications and replacements are not fully disclosed in the above descriptions, they have substantially been covered in the following claims as appended.