PATENT DOCUMENT

Publication Number: US-8687026-B2
Application Number: US-201113246961-A
Country: US
Kind Code: B2

Title: Systems and method for display temperature detection

Abstract:
Disclosed embodiments relate to a display temperature detection system that can detect temperature variations in different regions of a display panel. The temperature measuring display system includes a display panel that provides graphical images. Further, the temperature measuring display system includes temperature measurement circuitry. The temperature measurement circuitry includes one or more thermal diodes, transistors, or a mesh layer useful to determine at least one temperature measurement of the display panel.

Claims:
What is claimed is: 
     
       1. Temperature-measuring display system, comprising:
 a display panel configured to display a graphical image; 
 temperature measurement circuitry, comprising:
 a mesh layer disposed in or on the display panel, wherein the mesh layer comprises rows and columns of wire; 
 measurement circuitry configured to measure baseline resistance values or the baseline capacitance values or a combination thereof, at various points in a mesh layer disposed in or on the display panel and to determine temperature values in one or more areas of the display panel that correspond to various intersecting points of the rows and columns of the mesh layer based upon electrical attributes of the rows and columns in the mesh layer; and 
 
 a processor configured to control the display panel based at least in part upon the temperature values. 
 
     
     
       2. The temperature-measuring display system of  claim 1 , wherein the measurement circuitry is configured to determine the temperature values at each intersecting point of the rows and the columns. 
     
     
       3. The temperature-measuring display system of  claim 1 , wherein the temperature values represent a temperature measurement at the one or more areas of the display panel. 
     
     
       4. The temperature-measuring display system of  claim 1 , wherein the temperature values represent a change in temperature from baseline temperature values at the one or more areas of the display panel. 
     
     
       5. The temperature-measuring display system of  claim 1 , wherein the temperature measurement circuitry is configured to measure at least one of resistance values or capacitance values of the mesh layer in the plurality of locations that correspond to intersections of the rows and columns of wire and determine the temperature values of the intersections based at least in part upon the measured values of the mesh layer. 
     
     
       6. The temperature-measuring display system of  claim 5 , wherein the temperature measurement circuitry comprises a low-pass filter configured to filter high frequency components of the measured resistance values, the capacitance values, or a combination thereof. 
     
     
       7. The temperature-measuring display system of  claim 1 , comprising:
 a driver integrated circuit configured to provide data signals for the graphical image; and 
 one or more thermal diodes disposed in the driver integrated circuit, wherein the temperature measurement circuitry is configured to provide a temperature measurement of the driver integrated circuit based upon measurements obtained from the one or more thermal diodes. 
 
     
     
       8. The temperature-measuring display system of  claim 1 , comprising display circuitry configured to generate a temperature gradient map based at least in part upon the temperature values. 
     
     
       9. The temperature-measuring display system of  claim 8 , wherein the temperature gradient map comprises regions of temperature value ranges based at least in part upon the temperature values. 
     
     
       10. The temperature-measuring display system of  claim 1 , comprising the display circuitry configured to generate a white point gradient map based at least in part upon the temperature values. 
     
     
       11. The temperature-measuring display system of  claim 10 , wherein the white point gradient map comprises regions of white point value ranges based at least in part upon the temperature values. 
     
     
       12. The temperature-measuring display system of  claim 1 , comprising display circuitry configured to adjust one or more white point values based at least in part upon the temperature values. 
     
     
       13. The temperature-measuring display system of  claim 12 , wherein the display circuitry is configured to adjust the white point value to offset an increased blue color when one or more temperature values is above a baseline value. 
     
     
       14. The temperature-measuring display system of  claim 12 , wherein the display circuitry is configured to adjust the white point value to offset an increased yellow color when one or more temperature values is below a baseline value. 
     
     
       15. The temperature-measuring display system of  claim 1 , comprising communications circuitry or an input/output port configured to provide the temperature values to an entity external to the temperature-measuring display system. 
     
     
       16. A method, comprising:
 measuring, via measurement circuitry of a display panel, baseline resistance values or the baseline capacitance values or a combination thereof, at various points in a mesh layer disposed in or on the display panel, wherein the mesh layer comprises rows and columns of electrically conductive lines; 
 determining, via the measurement circuitry, a change in resistance, a change in capacitance, or combination thereof from the baseline resistance, capacitance, or combination thereof at various intersecting points of the rows and columns of electrically conductive lines in the mesh layer; 
 associating, via the processing circuitry, the change in resistance, the change in capacitance or combination thereof of the rows and columns of electrically conductive lines with one or more temperature values that correspond to various intersecting points of the rows and columns of electrically conductive lines; and 
 controlling the display panel, via the processing circuitry, based at least in part upon the temperature values. 
 
     
     
       17. The method of  claim 16 , wherein controlling the display panel comprises adjusting, via the circuitry, white point values of the display panel based at least in part upon the one or more temperature values. 
     
     
       18. The method of  claim 16 , wherein controlling the display panel comprises providing, via the circuitry, the one or more temperature values to an entity external to the display panel. 
     
     
       19. The method of  claim 16 , comprising comparing the one or more temperature values with a simulated temperature value to determine an accuracy of the simulated temperature value. 
     
     
       20. The method of  claim 16 , comprising determining a plurality of baseline temperature measurements by correlating the determined resistance values with the one or more temperature values. 
     
     
       21. The method of  claim 16 , comprising determining the one or more temperature values by correlating a range of resistance values with a specific temperature value. 
     
     
       22. The method of  claim 16 , comprising:
 filtering high frequency components from at least one of the baseline resistance values, the baseline capacitance values, the change in resistance, or the change in capacitance, via a low-pass filter; and 
 determining the one or more temperature values based at least in part upon at least one of the filtered baseline resistance values, the filtered baseline capacitance values, the filtered change in resistance, or the filtered change in capacitance. 
 
     
     
       23. An electronic device, comprising:
 a display panel configured to display a graphical image; 
 a processor configured to provide image data to the display panel; and 
 temperature measurement circuitry, comprising:
 a mesh layer disposed in or on the display panel, wherein the mesh layer comprises rows and columns of wire, and wherein resistance values, capacitance values, or a combination thereof at various intersecting points of the rows and columns of wire change based upon temperature changes of the display panel; 
 measurement circuitry, configured to determine at least one of the resistance values or the capacitance values at various intersecting points of the rows and columns of wire, wherein the processor is configured to determine one or more temperature values in one or more areas of the display based at least in part upon the resistance values, capacitance values, or combination thereof; and 
 a processor configured to control the display panel based at least in part upon the temperature values. 
 
 
     
     
       24. The electronic device, of  claim 23 , comprising output circuitry comprising at least one of an input/output port, a network interface, or an RF transmitter; wherein the processor is configured to transmit temperature statistics of the display panel via the output circuitry. 
     
     
       25. The electronic device of  claim 23 , comprising at least one of storage or memory configured to store temperature statistics of the display panel. 
     
     
       26. The electronic device of  claim 23 , comprising at least one input structure configured to accept an input from a user of the electronic device, wherein the input represents a request to display temperature statistics and the processor is configured to selectively provide image data representative of the temperature statistics to the display panel based upon the input. 
     
     
       27. A method, comprising:
 measuring, via measurement circuitry of a display panel, baseline resistance values or the baseline capacitance values or a combination thereof to determine a plurality of temperature values that correspond to various points in a mesh layer disposed in or on the display panel; 
 generating, via display circuitry, a temperature gradient map that corresponds to various intersecting points of rows and columns of the mesh layer disposed in or on the display panel based at least in part on the plurality of temperature values; and 
 adjusting, via processing circuitry, one or more white point values of the display panel based at least in part on the plurality of temperature values.

Description:
BACKGROUND 
     The present disclosure relates generally to display panels, and more particularly, to detection of temperatures within the display panels. 
     This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art. 
     Many electronic devices include display panels that provide visual images to a user of the electronic device. These display panels may emit non-uniform temperatures in various areas of the display panels. For example, in a display panel that uses light emitting diodes (LEDs), the display temperatures may be higher in regions near the LEDs than in regions further away from the LEDs. Also, heat generating components near the display screen, such as drivers, can also contribute to temperature variations on the display. 
     Temperature variations in the display panels may produce color maladies, such as producing more blue in higher temperature areas and producing more yellow in lower temperature areas. Thus, understanding the temperature variations in the display panels may help manufactures to counteract these color maladies. Manufactures of electronic devices may attempt to simulate the variations in temperature using software models. However, such models may be insufficient to understand the true nature of the color variations in physical prototypes of the display panels. Further these models merely provide a prediction of possible temperature variations. 
     SUMMARY 
     A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below. 
     Embodiments of the present disclosure relate to devices and methods for determining temperature values of a display. For example, the temperature values of the display may be obtained through thermal diodes and/or through measuring resistance and/or capacitance in a mesh layer. In certain embodiments, the temperature values of the display are used to adjust white points of the display to reduce color maladies based upon the non-uniform temperatures of the display. 
     Various refinements of the features noted above may exist in relation to various aspects of the present disclosure. Further features may also be incorporated in these various aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to one or more of the illustrated embodiments may be incorporated into any of the above-described aspects of the present disclosure alone or in any combination. Again, the brief summary presented above is intended only to familiarize the reader with certain aspects and contexts of embodiments of the present disclosure without limitation to the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which: 
         FIG. 1  is a schematic block diagram of an electronic device with display panel temperature measuring circuitry, in accordance with an embodiment; 
         FIG. 2  is a perspective view of a handheld electronic device including the display panel temperature measuring circuitry, in accordance with an embodiment; 
         FIG. 3  is a perspective view of a display panel with integrated temperature measurement circuitry, illustrating temperature varying elements of the display panel, in accordance with an embodiment; 
         FIG. 4  is a flowchart describing a process for adjusting white point values of a display panel based upon display panel temperature values, in accordance with an embodiment; 
         FIG. 5  is an illustration of a temperature gradient map, in accordance with an embodiment; 
         FIG. 6  is an illustration of a white point value map, in accordance with an embodiment; 
         FIG. 7  is a schematic diagram of temperature measuring circuitry, in accordance with an embodiment; 
         FIG. 8  is a flowchart depicting a process for determining temperature values of a mesh layer; and 
         FIG. 9  is a schematic diagram of display panel circuitry having temperature measuring elements, in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
     One or more specific embodiments will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
     As may be appreciated, electronic devices may include various components that contribute to the function of the device. For instance,  FIG. 1  is a block diagram illustrating components that may be present in one such electronic device  10 . Those of ordinary skill in the art will appreciate that the various functional blocks shown in  FIG. 1  may include hardware elements (including circuitry), software elements (including computer code stored on a computer-readable medium, such as a hard drive or system memory), or a combination of both hardware and software elements.  FIG. 1  is only one example of a particular implementation and is merely intended to illustrate the types of components that may be present in the electronic device  10 . For example, in the presently illustrated embodiment, these components may include a display  12 , temperature measurement circuitry  14 , input/output (I/O) ports  16 , input structures  18 , one or more processors  20 , one or more memory devices  22 , non-volatile storage  24 , a network interface  26 , an RF transmitter  28 , and an antenna  30  coupled to the RF transmitter  28 . The network interface  26  may provide communications capabilities through a wired (e.g., Ethernet) or wireless (e.g., Wi-Fi) network. Further, the RF transmitter  28  may provide communications through radio frequency signals. 
     The display  12  may be used to display various images generated by the electronic device  10 . For example, the processor  20  may provide image data to the display  12 . Further, the non-volatile storage  24  may be configured to store image data provided by the processor  20 . The display  12  may be any suitable liquid crystal display (LCD), such as a fringe-field switching (FFS) and/or an in-plane switching (IPS) LCD. Additionally, the display  12  may have touch-sensing capabilities that may be used as part of the control interface for the electronic device  10 . 
     The display  12  may be coupled to the temperature measurement circuitry  14 , which may be controlled by the processor  20  and/or other data processing circuitry of the electronic device  10  (e.g., logic circuitry of the display  12 ). As will be described in more detail below, the temperature measurement circuitry  14  may enable the processor  20  and/or other data processing circuitry to detect temperature values in one or more areas of the display  12 . These temperature values may be stored in the non-volatile storage  24  or communicated to an external entity (e.g., through use of the I/O ports  16 , the network interface  26 , or the RF transmitter  28 ). As will be described in more detail below, the temperature values may be useful in understanding real-world statistics of the display  12  as well as useful for adjusting the display  12  to provide better color quality. 
     The electronic device  10  may take the form of a cellular telephone or some other type of electronic device. In certain embodiments, electronic device  10  in the form of a handheld electronic device may include a model of an iPod® or iPhone® available from Apple Inc. of Cupertino, Calif. By way of example, an electronic device  10  in the form of a handheld electronic device  30  (e.g., a cellular telephone) is illustrated in  FIG. 2  in accordance with one embodiment. The depicted handheld electronic device  30  includes a display  12  (e.g., in the form of an LCD or some other suitable display) with the temperature measurement circuitry  14  of  FIG. 1 , I/O ports  16 , and input structures  18 . 
     Although the electronic device  10  is generally depicted in the context of a cellular phone in  FIG. 2 , an electronic device  10  may also take the form of other types of electronic devices. In some embodiments, various electronic devices  10  may include media players, personal data organizers, handheld game platforms, cameras, and combinations of such devices. For instance, the device  10  may be provided in the form of handheld electronic device  30  that includes various functionalities (such as the ability to take pictures, make telephone calls, access the Internet, communicate via email, record audio and video, listen to music, play games, and connect to wireless networks). In another example, the electronic device  10  may also be provided in the form of a portable multi-function tablet computing device. By way of example, the tablet computing device may be a model of an iPad® tablet computer, available from Apple Inc. Alternatively, the electronic device  10  may also be provided in the form of a desktop or notebook computer with the display  12 . For example, such a desktop or notebook computer may be a model of an iMac®, MacBook Air®, or MacBook Pro®. Although the following disclosure uses the handheld device  30  by way of example, it should be understood that the temperature measurement circuitry  14  may be employed in like fashion in any suitable form factor, such as those mentioned above. 
     The display  12  may display various images generated by the handheld electronic device  30 , such as a graphical user interface (GUI)  38  having icons  40 . The temperature measurement circuitry  14  may be useful in providing higher quality images (e.g., GUI  38 ) to the handheld electronic device  30  by providing temperature readings of the display  12 , such that the display  12  may be adjusted to counteract the effects of varying temperatures within the display  12 . Thus, a more accurate color representation for images may be displayed on the display  12 . 
     Effects of the temperature variations may be more clearly shown by describing elements of the display  12 .  FIG. 3  is an embodiment of the display  12  with the temperature measuring circuitry  14 . In the illustrated embodiment, a light source  80  is disposed along an edge  82  of the display  12  and is configured to provide light to the display  12 . The light source  80  may include light emitting diodes (LEDs)  84 , which may include a combination of red, blue, and green LEDs and/or white LEDs. In the illustrated embodiment, the LEDs  84  may be arranged on one or more printed circuit boards (PCBs)  86  adjacent to an edge (e.g., edge  82 ) of the display  12  as part of an edge-lit backlight assembly. In another embodiment, a backlight unit may be configured such that the LEDs  84  are arranged on one or more PCBs  86  at the back of the display  12  in a direct-lighting backlight assembly. The LEDs  84  may include multiple groupings of LEDs, and each grouping may be referred to as an LED string. Each string may include a subset of the LEDs  84 , and the LEDs within each string may be electrically connected in series with the other LEDs within the same string. The strings of LEDs  84  may be arranged end-to-end or may be interleaved. 
     When activated, the LEDs  84  may emit heat. Further, other heat generating components, such as display drivers  88  or other components of the handheld electronic device  30  may be positioned near the display  12  and affect temperatures of the display  12 . Temperature variations in the display  12  may create undesirable effects to the color quality of the display  12 . For example, in areas of the display  12  where there are increased or decreased temperatures, the white point of the display  12  may change. In areas with higher temperatures, more blue may be produced by light emitted from the LEDs  84 , and in areas of decreased temperatures, more yellow may be produced by the LEDs  84 . For example, in the illustrated embodiment, the LEDs  84  are mounted to the right side of the display  12 . Thus, heat emitted from the LEDs  84  may cause right portions of the display  12  to have an increased temperature over right portions of the display  12 . Thus, the right side of the display  12  may provide more blue when the LEDs  84  are activated and the left portions may provide more yellow when the LEDs  84  are activated. Such color variations may result in a lower quality image being provided by the display  12 . 
     To detect and/or counteract these color variations, temperature measurement circuitry  14  may be added to the display  12  to determine desirable adjustments of the display  12  design and/or white point values. For example, the temperature measurement circuitry  14  may include a mesh layer and/or thermal diodes that enable temperature values to be determined. As will be discussed in more detail below, the processor  20  and/or other data processing circuitry of the handheld electronic device  30  may associate resistance and/or capacitance values of the mesh layer  96  with temperature values or temperature variations in the display  12 . 
     The temperature measurements of the display  12  may be useful in helping handheld device manufacturers to understand the effects of the components of the handheld electronic device  30 . For example, the temperature measurement circuitry  14  may provide indications of heat producing components of the handheld electronic device  30 , and how these components affect the display  12 . The temperature measurements may be provided to external entities (e.g., the handheld electronic device manufacturers) through the I/O ports  16 , the network interface  26 , and/or the RF transmitter  28 . Further the manufacturers may observe the measured temperatures through information provided to the display  12 . The temperature measurements may be used by the manufacturers to adjust their design and/or manufacturing techniques to reduce temperature changes on the display. Moreover, the temperature measurements may provide a more complete indication of actual real-world usage scenarios of the display  12 . Further, the manufactures may create software models of the display  12  that attempt to determine potential temperature variations that are likely to occur. By comparing these simulated models with real-world temperature statistics of the display  12 , the manufacturer may be able to determine the accuracy of the software models of the display  12 . 
     Further, as previously discussed, the temperature measurements may be useful in altering white point values of the display  12  such that the color quality of the display  12  may be improved.  FIG. 4  is a flowchart that depicts a process  200  for altering the white point values of the display  12  based upon determined temperature measurements. To alter the white point values, temperatures of the display  12  are determined (block  202 ). The temperature determinations may include determining a measurement of change in the temperature, or an actual temperature of certain regions of the display  12 . For example, the temperature detection circuitry  14  may determine an increase of 10 degrees in a certain region or may detect that a certain region is 110 degrees. 
     The temperature determinations may be used to define a temperature gradient map  220 , as depicted in  FIG. 5  (block  204 ). The temperature gradient map  220  provides regions of temperature values (e.g., T 1 -T 6 ) for the display  12  based upon the temperature determinations. In some embodiments, the temperature regions (e.g., T 1 -T 6 ) may be determined by threshold ranges of temperature changes or temperature values. For example, temperature region T 1  may be temperature changes in the range of 25-30 degrees, temperature region T 2  may be temperature changes in the range of 23-24 degrees, temperature region T 3  may be temperature changes in the range of 15-22 degrees, etc. In other embodiments, the gradient map  220  may be much more granular. 
     As previously discussed, temperature fluctuations in the display  12  may affect the color quality of the display. For example, in areas of the display  12  where the temperature is hotter, blue hues may be present. In areas of the display  12  where the temperature is cooler, yellow hues may be present. Thus, it may be beneficial to associate white point values of the display  12  with the temperatures obtained from the temperature gradient map  220  (block  206 ) to counteract color quality maladies introduced by temperature variations in the display  12 . For example,  FIG. 6  illustrates a white point gradient map  222  that is derived by associating white point values with the temperature gradient map  220  of  FIG. 5 . As previously discussed, the white point values may change based upon temperature changes in the display  12 . For example, as temperature increases within the display  12 , more blue may be presented. Further, as temperature decreases within the display  12 , more yellow may be presented. Thus, new target white point values (e.g., WP 1 -WP 6 ) may be applied based upon the temperature determinations. For example, the new target white point values may be applied to the temperature gradient map. The new target white point values may represent changes that may be provided to the original white point configuration of the display  12  to account for the temperature determinations. For example, the target white point value WP 1  may be associated to determined temperature T 1 . T 1  may be a hot temperature value, causing a blue tint to be emitted. Target white point value WP 1  may include white point values that increase a yellow tint to offset the emitted blue tint. 
     The white points of the display may be modified based upon the white point values (e.g., WP 1 -WP 7 ) (block  208 ). Any suitable way of altering the white point of the display  12  may be employed. For example, in one embodiment, the white points of the display  12  may be modified by altering an amount of current passing through the LEDs  84 , to adjust the white points. For example, if the emitted white point has a blue tint when compared to the target white point, the current through a string of yellow tinted LEDs  84  may be increased to produce an output that substantially matches the target white point. By increasing the current through strings of LEDs  84 , the overall brightness of backlight  80  also may increase. In other embodiments, the ratio of the currents passing through LED strings may be adjusted to emit a white point that substantially matches the target white point while maintaining a relatively constant brightness. 
     In certain embodiments, the white points of the display  12  may be modified through software instructions provided to the processors  20  of the handheld electronic device  30 . The processors  20  may provide modified image data to the display circuitry of the display  12  based upon temperature measurements obtained through the temperature detection circuitry  14  or the temperature gradient map  220 . The modified image data may modify the color attributes of the image to reduce blue or yellow hues caused by variations in temperature. 
     Additionally, it may be beneficial for manufacturers to understand the display  12  temperature variations occurring in the field. In certain embodiments, temperature statistics for the handheld electronic device  30  (e.g., the temperature measurements obtained by the temperature detection circuitry  14 , temperature gradient maps  220 , or statistical data relating to the temperature measurements) may be provided to the manufacturer from the handheld electronic device  30 . For example, the temperature statistics may be provided to the manufacturer through the I/O ports  16 , the network interface  26 , or the RF transmitter  28 . The statistical information may be useful in providing display  12  troubleshooting when issues arise and may help the manufactures provide enhanced designs by understanding real-world temperature measurements of the display  12  in the field. 
     As previously discussed, embodiments of the temperature measurement circuitry  14  may include using attributes of a conductive mesh layer disposed in or on the display  12  to determine temperatures in one or more areas of the display  12 . Further, in certain embodiments, thermal diodes may be used to determine temperature values of the display  12 . 
     To illustrate the temperature measurement capabilities using the mesh layer  96 ,  FIGS. 7 and 8  will be discussed in conjunction.  FIG. 7  illustrates the mesh layer  96  with measurement circuitry  254 .  FIG. 8  is a flowchart depicting a process  260  for determining temperature values using the mesh layer  96 . As illustrated in  FIG. 8 , the mesh layer  96  may include rows  250  and columns  252  of wire. In some embodiments, the wire may include indium tin oxide (ITO). The rows  250  and columns  252  may be coupled to measurement circuitry  254 . In certain embodiments, the measurement circuitry  254  may measure a baseline resistance and/or capacitance at the portions of the mesh layer  96  where the rows  250  and columns  252  intersect (e.g., areas  256 ) (block  262 ). In certain embodiments, the temperature measurements may be associated with resistance and/or capacitance values that transition slowly because temperatures may not change rapidly over time. Thus, rapid variations in resistance and/or capacitance may be filtered with a high frequency filter (i.e., a low pass filter) (block  264 ). The measurement circuitry  254  may then provide the filtered resistance and/or capacitance measurements to the processor  20  or other data processing circuitry. 
     The processor  20  or other data processing circuitry may associate the filtered resistance and/or capacitance measurements with temperature values (block  266 ). For example, as temperature decreases, the resistance of the wires may decrease. Further, computer models or experimental data may provide a correlation between temperature values and capacitance values, such as a decrease in temperature correlating to an increase in capacitance. Thus, the resistance and/or capacitance values of the areas  256  may be associated with temperature values in the mesh layer  96 , and thus, temperature values in the display  12 . In certain embodiments the association between the resistance and/or capacitance values with temperature values may be provided by a lookup table stored in the memory  22  or storage  24  of  FIG. 1 . In other embodiments, the temperature values may be calculated through processor  20  instructions using the resistance and/or capacitance values. 
     In some embodiments, the measurement circuitry  254  may determine temperature changes rather than actual temperature measurements of the display  12 . For example, baseline resistances and/or capacitances may be determined at various points in the mesh layer  96  (e.g., areas  256 ) by the measurement circuitry  254 . As discussed above, a low-pass filter may filter high frequency changes in the resistance and/or capacitance. The measurement circuitry  254  may detect changes from the baseline resistance and/or capacitance and associate the changes in resistance and/or capacitance with temperature changes in the display  12 . For example, if the resistance decreases from the baseline resistance at a certain point, the processor  20  may associate the decrease in resistance with a decrease in temperature because as temperature decreases resistance decreases. Further, if an increase in resistance is detected, the processor  20  may associate the change with an increase in temperature. 
     In some embodiments, other temperature measurement circuitry may be included in the display  12 . For example, thermal diodes may determine temperature values of certain areas of the display  12 .  FIG. 9  is a schematic view of display circuitry  300  with a mesh layer  96  and thermal diodes  302  incorporated into the data line driving circuitry  304  and driving circuitry  306 . As depicted, the pixels  308  may be disposed in a matrix that forms an image display region of the display  12 . In such a matrix, each pixel  308  may be generally defined by the intersection of data or source lines (or “wires”)  310  and scanning or gate lines (or “wires”)  312 . The pixel array may also include common lines (or “wires”)  314  to apply voltages to common electrodes of the pixel array. 
     In the depicted embodiment, the data line driving circuitry  304  sends image or data signals to the pixels via the respective data lines  310 . Such image signals may be applied by line-sequence (i.e., the data lines  310  may be sequentially activated during operation). The gate lines  312  may provide scanning signals from the driving circuitry  306  such that thin film transistors (TFTs) may be activated and deactivated (i.e., turned on and off) based on the respective presence or absence of a scanning signal. When activated, the TFTs may store the image signals received via a respective data line  310 . In certain embodiments, the data lines  310  and the gate lines  312  may make up the mesh layer  96 . In such embodiments, measurement circuitry  254  may be coupled to the data lines  310  and the gate lines  312  such that temperature values may be determined by using the mesh layer  96  as discussed above. 
     It may be beneficial to determine additional temperature values near other components of the display  12 . For example, the driving circuitry  304  and/or  306  may produce heat, causing locations of the display  12  to be warmer near the driving circuitry  304  and/or  306 . Thermal diodes  302  incorporated into the data line driving circuitry  304  and the driving circuitry  306  may be useful in determining temperatures in the driving circuitry  304  and  306 . The thermal diodes  302  may be provided with a steady current from the data line driving circuitry  304  and the driving circuitry  306 . The processor  20  of  FIG. 1  or other data processing circuitry may be used to measure a voltage in the thermal diodes  302  that changes as temperature changes within the display  12 . For example, as the temperature of the thermal diodes  302  increases, the voltage provided by the thermal diodes  302  may decrease. The change in voltage provided by the thermal diodes  302  may be associated with specific temperature values, or may be associated with a specific temperature change in the data line driving circuitry  304  and/or the driving circuitry  306 . The temperature measurements gathered from the thermal diodes  302  may be stored in the storage  24 . 
     Determining display  12  temperatures may be very useful in manufacturing high quality displays  12 . Measuring display  12  regions (e.g., areas  256 ) to determine temperature measurements may enable manufacturers to more clearly understand the effects of integrated circuit designs of handheld electronic devices  30  during the design process. Further, in certain embodiments, such temperature measurement may be useful in dynamically adjusting white points of the handheld electronic device  30  to obtain better image quality on the display  12 . Further, temperature statistics may help manufacturers create enhanced designs based upon real-world usage. 
     The specific embodiments described above have been shown by way of example, and it should be understood that these embodiments may be susceptible to various modifications and alternative forms. It should be further understood that the claims are not intended to be limited to the particular forms disclosed, but rather to cover all modifications, equivalents, and alternatives falling within the spirit and scope of this disclosure.

Metadata:
Filing Date: 20110928
Publication Date: 20140401
Grant Date: 20140401
Priority Date: 20110928
Inventors: WURZEL JOSHUA GREY
AL-DAHLE AHMAD
Assignee: APPLE INC
CPC Classifications: [{"code": "G09G2320/0242", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3426", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G3/3677", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/0666", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01K2213/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01K1/026", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G3/3677", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/041", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3688", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G2320/0242", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3426", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01K2213/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2320/0666", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3688", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G2320/041", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01K1/026", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 47089132