Patent Publication Number: US-7717601-B2

Title: Systems and methods for compensating brightness uniformity of backlit image displays

Description:
FIELD OF THE INVENTION 
   This invention relates generally to image display and, more particularly, to backlighting image displays. 
   BACKGROUND OF THE INVENTION 
   As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems. 
   Display devices for information handling systems include liquid crystal display (LCD) display devices. Most LCD display devices employ cold cathode fluorescent lamp (CCFL) backlights for lighting the display. In one typical configuration illustrated in cross-section in  FIG. 1 , a LCD display device  100  is shown coupled to an information handling system  120  (such as a desktop personal computer) and includes a LCD backlight module  102  that is provided for lighting a transmissive LCD display panel  104 . Such a transmissive display panel  104  typically includes multiple layers (e.g., diffuser layer  130 , input polarizer layer  132 , LCD crystal layer  134 , output polarizer layer  136 ) that together operate to produce an image based on image data  122  provided by graphics/video processing components of information handling system  120 . As shown in  FIG. 2 , LCD backlight module  102  includes multiple “U-shaped” CCFL backlights  106  that are disposed in spaced relationship to each other within a “light pipe” area  116  of the LCD backlight module  102 . The multiple CCFL backlights  106  are distributed in top-to-bottom relationship and across the planar area of the LCD backlight module  102  as shown. As illustrated in  FIGS. 1 and 2 , LCD backlight module  102  is also provided with a reflector  108  that helps to direct light  110  produced by the CCFL backlights  106  toward the LCD display panel  104 . 
   Uneven brightness and poor brightness uniformity are problems that are often experienced by conventional LCD display devices such as illustrated in  FIGS. 1 and 2 . These brightness problems may occur initially or over time due to a number of factors, such as due to the physical arrangement of the CCFL backlights  106  (e.g., uneven lamp spacing), stray capacitance that shunts partial lamp current between the two cathodes, light loss toward the ends of CCFL backlights  106  that are adjacent connectors for power  112 , and aging of the CCFL backlights  106 . It is typical for the brightness uniformity to deteriorate over time with use and wear of the CCFL backlight power connectors. 
   SUMMARY OF THE INVENTION 
   Disclosed herein are systems and methods for compensating brightness uniformity of transmissive backlit display devices. The disclosed systems and methods may be implemented using auxiliary lights (e.g., white light emitting diode and/or 3-color RGB light emitting diode lights) to provide additional light to compensate light provided by the main backlights (e.g., CCFL backlights) of a backlit image display device. Such auxiliary lights may be, for example, embedded into the light pipe area of an image display and/or placed in any other suitable position relative to the main backlights that is suitable for compensating the main backlights. For example, auxiliary backlights may be inserted on the side opposite the light pipe and/or between the main backlights depending on the particular shape and arrangement of the main backlight lamps. In one exemplary embodiment, white or 3-color light emitting diode (LED) lights having an adjustable color temperature (white point) may be employed as auxiliary backlights so that the color temperature produced for compensation may be adjusted to match the color temperature characteristics of the existing main backlights of the image display, e.g., for 72%, 92% or 102˜4% high color gamut CCFL panels. 
   The disclosed systems and methods may be implemented in one exemplary embodiment to compensate brightness uniformity of a transmissive image display based at least in part on measured luminance of one or more areas of the display. In this regard, brightness uniformity of a display device may be adjusted based on display luminance measured at the factory (e.g., during assembly or calibration of an image display), and/or may be adjusted at any time later during the operating life of the image display based on luminance measurements that may be made using external light metering sensor/s and/or light metering sensor/s that are integral or provided internal to the display device itself. In one exemplary embodiment, a feed back loop may be provided that allows image display brightness uniformity to be adjusted in real time based on real time display brightness measurements received from one or more light metering sensor/s provided as integral components of the display device. In another embodiment, brightness uniformity of a display device may be adjusted based on user input, e.g., using an I/O device of an information handling system coupled to the display device. This capability advantageously allows a user to adjust display brightness uniformity to match the conditions under which the display is being viewed. 
   In one respect, disclosed herein is a method of compensating brightness uniformity of display for an information handling system, including: providing a transmissive display panel and one or more main backlight lamps configured to provide light to the transmissive display panel; providing one or more auxiliary backlight lamps configured to supplement light provided by the main backlight lamps to light the transmissive display panel; lighting an area of the transmissive display panel with the main backlight lamps; and providing light from the auxiliary backlight lamps to supplement light provided by the main backlight lamps to light the area of the transmissive display panel. In this exemplary method, the area of the transmissive display panel is lit with a first brightness uniformity by the main backlight lamps alone, and the area of the transmissive display panel is lit with a second brightness uniformity by the main backlight lamps and the auxiliary backlight lamps together, the second brightness uniformity being greater than the first brightness uniformity. 
   In another respect, disclosed herein is a display for an information handling system, including: a transmissive display panel and one or more main backlight lamps configured to provide light to an area of the transmissive display panel; and one or more auxiliary backlight lamps configured to supplement light provided by the main backlight lamps to light the transmissive display panel. In this exemplary method, the area of the transmissive display panel is lit with a first brightness uniformity by the main backlight lamps alone, and the area of the transmissive display panel is lit with a second brightness uniformity by the main backlight lamps and the auxiliary backlight lamps together, the second brightness uniformity being greater than the first brightness uniformity. 
   In another respect, disclosed herein is a method of compensating brightness uniformity of a display for an information handling system, including: providing a transmissive display panel, one or more backlights configured for lighting the transmissive display panel, and one or more auxiliary backlight lamps configured for selectably lighting the transmissive display panel; lighting the transmissive display panel with one or more main backlight lamps; and increasing the brightness uniformity of the transmissive display panel by selectably adjusting the brightness of the one or more auxiliary backlight lamps. 
   In another respect, disclosed herein is an information handling system and display, including: a transmissive display panel; one or more backlights configured for lighting the transmissive display panel; one or more auxiliary backlight lamps configured for selectably lighting the transmissive display panel; and one or more auxiliary backlight control components configured to increase a brightness uniformity of the transmissive display panel by selectably adjusting the brightness of the one or more auxiliary backlight lamps. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a simplified overhead cross-sectional view of a conventional LCD display device. 
       FIG. 2  is a simplified side cross-sectional view of a conventional LCD display device. 
       FIG. 3  is a simplified overhead cross-sectional view of a LCD display device configured according to one exemplary embodiment of the disclosed systems and methods. 
       FIG. 4  is a simplified side cross-sectional view of a LCD display device configured according to one exemplary embodiment of the disclosed systems and methods. 
       FIG. 5  is a simplified side cross-sectional view of a LCD display device configured according to one exemplary embodiment of the disclosed systems and methods. 
       FIG. 6  illustrates a brightness calibration procedure according to one exemplary embodiment of the disclosed systems and methods. 
       FIG. 7  illustrates active display area of a display device according to one exemplary embodiment of the disclosed systems and methods. 
   

   DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     FIG. 3  illustrates an overhead cross-sectional view of an LCD display device  300  configured according to one exemplary embodiment of the disclosed systems and methods. LCD display device  300  may be employed as, for example, an image display monitor for a desktop portable information handling system (e.g., desktop PC), an image display monitor for a portable information handling system (e.g., notebook computer), a television display, an instrument display (e.g., processing plant instrument display, aircraft or other vehicle instrument display), etc. In this exemplary embodiment, LCD display device  300  is shown coupled to an information handling system  320  which may be, for example, a desktop personal computer or other components of a portable information handling system such as a notebook computer that is configured with graphics/video processing component/s  324  and auxiliary backlight control component/s  326 . It will be understood that the embodiment of  FIG. 3  is exemplary only, and that any other configuration of image display device having one or more auxiliary backlights and one or more external (non-integrated) or integrated auxiliary backlight control components may be employed that is suitable for controlling auxiliary backlight/s in a manner as described elsewhere herein. 
   Still referring to  FIG. 3 , LCD display device  300  includes a LCD backlight module  302  that is provided for lighting transmissive LCD display panel  304 . In this exemplary embodiment, transmissive display panel  304  includes diffuser layer  330 , input polarizer layer  332 , LCD crystal layer  334  and output polarizer layer  336  that together operate to produce an image based on image data  322  provided by graphics/video processing components  324  of information handling system  320 . However, it will be understood that a transmissive display device may be configured with any other configuration of transmissive display panel that is suitable for receiving light from one or more backlights and for modifying the received light to displaying an image. 
     FIG. 4  illustrates a front cross-sectional view of LCD backlight module  302  of  FIG. 3 . As shown in  FIG. 4 , backlight module  302  includes multiple “U-shaped” CCFL backlights  306  that are disposed in spaced relationship to each other within light pipe area  316  of LCD backlight module  302 . In this embodiment, multiple CCFL backlights  306  are distributed in top-to-bottom relationship and across the planar area of LCD backlight module  302  as shown. In this configuration multiple CCFL backlights  306  are configured to provide light to light substantially the entire area of LCD display panel  304 , although reduced areas of brightness may nevertheless exist within this area. 
   As illustrated in  FIGS. 3 and 4 , LCD backlight module  302  is also provided with a reflector  308  that helps to direct light  310  produced by CCFL backlights  306  toward LCD display panel  304 . Although LCD backlight module  302  is provided in this exemplary embodiment with multiple U-shaped backlights  306 , it will be understood that any other shape and/or configuration of one or more backlights suitable for backlighting a transmissive display panel may be employed in the practice of the disclosed systems and methods, e.g., multiple rod-shaped backlights extending at least partially across the width of a LCD backlight module in parallel relationship to each other with a connector on each end, etc. Furthermore, although LCD backlight module  302  is provided in this embodiment with CCFL backlights, other types of backlights may be employed within a backlight module including, but not limited to, hot cathode fluorescent lamp (HCFL), phosphorescent light source, external electrode light-emitting lamp (EEFL), electro luminance (EL), LED, etc. 
   Still referring to  FIGS. 3 and 4 , LCD backlight module  302  is provided in this embodiment with multiple auxiliary lights  380  that are supported by printed circuit board (PCB)  382  disposed along the external edge of light pipe area  316  so that auxiliary backlights  380  are embedded in the light pipe area  316 . In this exemplary embodiment auxiliary lights  380  are mounted to extend from the same edge of light pipe area  316  as are CCFL backlights  306 , and auxiliary lights  380  are mounted in substantially the same plane relative to LCD backlight module  302  as are CCFL backlights  306 . As shown, auxiliary lights  380  are mounted to face inward to light pipe area  316  of LCD backlight module  302  so as to emit light  360  into light pipe  316  in a manner that is reflected by reflector  308  to supplement light emitted by CCFL backlights  306  to LCD display panel  304  from edge area  390  of LCD backlight module  302 . In this exemplary embodiment, an optional diffuser layer  384  is provided between auxiliary backlights  380  and CCFL backlights  306  for purposes of diffusing the light from the CCFL lamps to achieve a uniformly illuminated surface. 
   With regard to the exemplary embodiment of  FIGS. 3 and 4 , brightness measurements have shown that brightness uniformity problems may be worse at the edges of some display devices, particularly at the backlight connector side of a display device where brightness may be less (e.g., about 10 to 15% less) than the center of the display device. Thus, auxiliary backlights  380  may be placed in one or more locations within a given display device that are selected to compensate for reduced brightness areas of the given display device, whether at the edge/s or elsewhere within the area of the display (e.g. toward the center or interior area of the display). Such reduced brightness areas may change over time as a given LCD display device ages and its CCFL backlights develop dim spots. Location/s of such an area of reduced brightness may be identified, for example, based on brightness testing of different points within a given display device (i.e., without auxiliary backlights  380 ), either with new CCFL backlights and/or over time as its CCFL backlights age. Therefore, it will be understood that the particular configuration of auxiliary backlights  380  relative to area  390  shown in  FIGS. 3 and 4  is exemplary only. 
   In one exemplary embodiment, auxiliary backlights  380  may be white or 3-color light LED lights having an adjustable color temperature (white point) so that the color temperature produced for brightness compensation may be adjusted to match the color temperature characteristics of the existing main backlights of the image display, e.g., for 72%, 92% or 102˜4% high color gamut CCFL panels. 
   It will be understood that the configuration (e.g., placement and number) of auxiliary backlights of  FIGS. 3 and 4  for brightness compensation is exemplary only. In this regard, the layout and number of auxiliary backlights may be selected to meet the brightness compensation needs and/or characteristics of a particular display device application (e.g., including shape, type and arrangement of particular backlight lamps employed in the application and the brightness uniformity that is desired). For example, given the display device configuration of  FIGS. 3 and 4 , more auxiliary backlights  380  may be embedded at the opposite edge of the light pipe area  316  from the CCFL backlight connectors and/or may be placed in-between one or more pairs of adjacent CCFL backlights  306  (e.g., mounted in reflector  308  to provide more coverage and brightness compensation). 
     FIG. 5  illustrates one possible configuration for a display device configuration that employs rod-shaped backlights extending across the width of the LCD backlight module  302  in parallel relationship to each other with a connector on each end, and having multiple auxiliary backlights  380   a  embedded at one edge of light pipe area  316  to emit light in-between each pair of CCFL backlights  306  (e.g., toward a first edge area  390  of LCD backlight module  302 ), multiple auxiliary backlights  380   c  embedded at the opposite edge of light pipe area  316  to emit light in-between each pair of CCFL backlights  306  (e.g., toward a second edge area  390  of LCD backlight module  302 ), and multiple auxiliary backlights  380   b  mounted in a position between the external edges of light pipe area  316  and in the interior area of LCD backlight module  302  so as to emit light in-between each pair of CCFL backlights  306  (e.g., toward the center of LCD backlight module  302 ) as shown. Thus, a display device may be configured with auxiliary backlights that emit light at one or more edge area locations of a transmissive display panel, and/or at one or more interior area locations (including adjacent a center area location) of a transmissive display panel. In this regard, auxiliary backlights  380  may be mounted at any one or more locations within an interior area of a LCD backlight module  302  of a display device  300 . 
   Referring again to  FIG. 3 , LCD display device  300  may be provided in one exemplary embodiment with one or more integral light metering sensors  392  configured to monitor brightness at one or more points within display device  300 . As shown, measured brightness data  350  may be provided from sensor/s  392  to auxiliary backlight control component/s  326  which may be configured to adjust brightness of one or more auxiliary lights  380  (e.g., by varying auxiliary backlight current  352  provided to auxiliary light/s  380  or by supplying a brightness control signal to another component that adjusts brightness of auxiliary backlight/s  380 ) based on measured brightness data  350 . Auxiliary backlight control component/s  326  may include, for example, memory and one or more processors that are executing software and/or firmware suitable for performing the brightness uniformity adjustments and/or calibration procedures as described elsewhere herein. 
   Still referring to the embodiment of  FIG. 3 , such a brightness adjustment may be made, for example, by increasing brightness of an auxiliary backlight  380  in a given area of display device  300  in response to measurement of low brightness level (e.g., low brightness level relative to a target brightness level needed for desired uniformity) at the given location by a sensor  392 . A similar methodology may be employed to decrease brightness of an auxiliary backlight  380  in a given area of display device  300  in response to measurement of high brightness level (e.g., high brightness level relative to a target brightness level needed for desired uniformity) at the given location by a sensor  392 . In this regard, a brightness adjustment may be made automatically (e.g., via brightness uniformity algorithm executed by auxiliary backlight control component/s  326 ) and/or may be made manually (e.g., by a user of information handling system  320 ) via input/output devices such as keyboard, mouse, and/or via graphical user interface. 
     FIG. 6  illustrates one exemplary embodiment of brightness calibration procedure  600  that may be employed to compensate brightness uniformity for a transmissive display device, e.g., such as LCD display devices  300  of  FIGS. 3-5 . In this regard, calibration procedure  600  may be performed at any time during the life or operation of a LCD display device  300 , e.g., at the factory when assembled, by a customer after purchase, etc. Moreover calibration procedure  600  may be performed automatically by auxiliary backlight control component/s  326  of an information handling system  320  (e.g., coupled to receive measured brightness data  350  from one or more integral light metering sensor/s  392  and to control brightness uniformity by varying auxiliary backlight current  352  provided to one or more auxiliary light/s  380  or by supplying a brightness control signal), may be performed by firmware and/or software of a separate measurement instrument configured to receive measured display brightness data from one or more external light metering sensors and to output brightness control information to allow a user to manually vary auxiliary backlight brightness and/or to supply brightness control signal/s to a LCD display device to control auxiliary backlight brightness, may be performed manually by taking one or more manual measurements of display brightness and manually varying manually varying auxiliary backlight brightness based on the manual measurements, etc. 
   As shown in  FIG. 6 , exemplary calibration procedure  600  starts in step  602 , e.g., in response to a command from a user, as part of an automated periodic calibration, in response to an automatic brightness uniformity measurement that deviates from a brightness uniformity set point, etc. Calibration procedure proceeds to step  604  where brightness of a LCD display device is measured at one or more points across the display area. In this regard, display brightness may be measured at any given point internal to a LCD display device  300  (e.g., within a LCD backlight module using an integral light metering sensor) or external to a LCD display device  300  (e.g., using external handheld or mounted light metering sensor applied to the front screen area of a LCD display device  300 ). Examples of equipment that may be employed to measure brightness in step  602  include, but are not limited to, color analyzers (e.g., using a Minolta CA210) employed under display-assembly factory conditions, or monitor calibration tools (e.g., ColorVision SpyderPro) employed by an end-user or customer in the home or office. 
   It will be understood that as few as one brightness point may be measured in step  604 . However, in one exemplary embodiment multiple brightness points may be measured as illustrated in  FIG. 7 . In this regard,  FIG. 7  shows an active display area  700  of a display device  300  having vertical dimension denoted by “V” and horizontal dimension denoted by “H”. Multiple brightness points  1  through  13  are shown in  FIG. 6 , each of which represents a point where brightness of LCD display device  300  is measured, e.g., by integral or external light metering sensor). Examples of brightness point patterns include, but are not limited to, a 9-point brightness measurement procedure in which brightness measurements are taken at the first 1-9 brightness points illustrated in  FIG. 7 , or a 13-point brightness measurement procedure in which brightness measurements are taken at the first 1-13 brightness points illustrated in  FIG. 7 . Although multiple brightness points  1 - 13  are arranged in a matrix orientation in  FIG. 7 , it will be understood that any other suitable orientation of multiple display devices may be employed, including multiple points that are distributed uniformly or non-uniformly across the active display area of a display device. 
   After brightness is measured at one or more points in step  604 , measured brightness data may be input into a brightness uniformity calibration software tool in step  606 . Such a brightness uniformity calibration software tool may be executing, for example, on auxiliary backlight control component/s  326  of information handling system  320  of  FIG. 3 , or on any other suitable processor or combination of processors. Measured brightness data may then be analyzed in step  608  and the brightness of one or more auxiliary backlights  380  adjusted by the brightness uniformity calibration software tool based on the measured brightness data of step  604 . Using the disclosed systems and methods, the brightness uniformity of an image display such as LCD display device  300  of  FIG. 3  may be compensated using any methodology suitable for increasing the uniformity of at least a portion of the total area of an image display. 
   Where brightness of a image display is measured at multiple points such as illustrated in the exemplary embodiment of  FIG. 7 , brightness uniformity (δ WHITE-Full White Screen Pattern ,) of the image display may be defined as the minimum measured brightness value of all measured brightness points divided by the maximum measured brightness of all measure brightness points for a given measurement cycle as follows: 
   
     
       
         
           
             
               
                 
                   δ 
                   WHITE 
                 
                 = 
                 
                   
                     
                       Minimum 
                       ⁢ 
                       
                           
                       
                       ⁢ 
                       
                         ( 
                         
                           
                             L 
                             
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                               ⁢ 
                               
                                   
                               
                               ⁢ 
                               1 
                             
                           
                           , 
                           
                             L 
                             
                               on 
                               ⁢ 
                               
                                   
                               
                               ⁢ 
                               2 
                             
                           
                           , 
                           
                             … 
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                             ⁢ 
                             
                               L 
                               onx 
                             
                           
                         
                         ) 
                       
                     
                     
                       Maximum 
                       ⁢ 
                       
                           
                       
                       ⁢ 
                       
                         ( 
                         
                           
                             L 
                             
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                               ⁢ 
                               
                                   
                               
                               ⁢ 
                               1 
                             
                           
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                               ⁢ 
                               
                                   
                               
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                         ) 
                       
                     
                   
                   × 
                   100 
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                 Eq 
                 . 
                 
                     
                 
                 ⁢ 
                 
                   ( 
                   1 
                   ) 
                 
               
             
           
         
       
     
       
       
         
           where: L on  is measured luminance for each brightness measurement point 1 through x. 
         
       
     
  
   For example, given nine measured brightness points (e.g., measured in step  604  at points  1 - 9  of  FIG. 7 ), brightness uniformity (δ WHITE ) may be represented as follows: 
   
     
       
         
           
             δ 
             WHITE 
           
           = 
           
             
               
                 Minimum 
                 ⁢ 
                 
                     
                 
                 ⁢ 
                 
                   ( 
                   
                     
                       L 
                       
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                         1 
                       
                     
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                         2 
                       
                     
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                       ⁢ 
                       
                         L 
                         
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                           ⁢ 
                           
                               
                           
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                           9 
                         
                       
                     
                   
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                 Maximum 
                 ⁢ 
                 
                     
                 
                 ⁢ 
                 
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                         ⁢ 
                         1 
                       
                     
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                         ⁢ 
                         
                             
                         
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                         2 
                       
                     
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                       … 
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                         L 
                         
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                           9 
                         
                       
                     
                   
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             × 
             100 
             ⁢ 
             
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   Still referring to  FIG. 6 , brightness uniformity (δ WHITE ) of an image display may be compensated by (δ WHITE ) varying brightness of one or more auxiliary backlights to maximize the brightness uniformity (δ WHITE ) value calculated using Equation 1. This may be done, for example, by varying current provided by auxiliary backlight control components  326  to one or more auxiliary backlights  380  so as to maximize the value of δ WHITE  in Equation 1. It will be understood that the value of δ WHITE  may be maximized in this manner regardless of the overall brightness level of a image display such as LCD display device  300 . In this regard, overall brightness level of a image display may be set in one embodiment prior to initiating step  602  of  FIG. 6  by varying the main backlights (e.g., CCFL backlights  306 ) to meet a given user profile, user input (e.g., via brightness hotkeys), information handling system state (e.g., battery or AC power mode), and/or sensed ambient operating conditions (e.g., bright sunlight or office conditions versus nighttime or dim indoor lighting conditions). Brightness uniformity may then be maximized using the methodology of  FIG. 6  for the given overall brightness level of the display. 
   As shown by optional flow path  610  in  FIG. 6 , calibration procedure  600  of  FIG. 6  may optionally repeat in an iterative manner, e.g., when performed by auxiliary backlight control components  326  of  FIG. 3 . In this way, brightness uniformity may be continually adjusted over time (e.g., to compensate for deteriorated brightness uniformity value over time and/or to adjust brightness uniformity value with changing overall display brightness level). Alternatively, steps of calibration procedure  600  of  FIG. 6  may be performed once without repeating (e.g., in response to user command). 
   It will be understood that the steps of calibration procedure  600  of  FIG. 6  are exemplary only, and that any other combination of additional, alternative, or fewer steps may be employed that are suitable for compensating brightness uniformity of an image display in a manner as described elsewhere herein. It will also be understood that measured brightness data may be analyzed manually and/or adjustments to auxiliary backlights be made manually (e.g., by a user or technician), and that the disclosed calibration procedure may be applied to compensate brightness uniformity of types of transmissive display devices other than an LCD display device. 
   For purposes of this disclosure, an information handling system may include any instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, entertainment, or other purposes. For example, an information handling system may be a personal computer, a PDA, a consumer electronic device, a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system may include memory, one or more processing resources such as a central processing unit (CPU) or hardware or software control logic. Additional components of the information handling system may include one or more storage devices, one or more communications ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, and a video display. The information handling system may also include one or more buses operable to transmit communications between the various hardware components. 
   While the invention may be adaptable to various modifications and alternative forms, specific embodiments have been shown by way of example and described herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. Moreover, the different aspects of the disclosed methods and systems may be utilized in various combinations and/or independently. Thus the invention is not limited to only those combinations shown herein, but rather may include other combinations.