Patent Application
20080068362
Recent years have seen considerable advances in the dynamic information presentation marketplace, particularly with regard to the use of plasma display technology. Conventionally, the dynamic advertising market uses networked plasma-based display systems because of its excellent optical characteristics, thin profile and wide viewing angle. Since the original commercial introduction of 42-inch plasma display products, use of this technology as a “Digital Ad Board” has become fairly commonplace. In a Digital Ad Board application the entire screen is typically used to display an “ad loop,” or a series of full-screen advertisements that cycle on a regular basis.
One peculiarity of plasma display technology is its tendency to “burn in” if a static image is displayed in the same location over a continued period of time. This burn-in is a physical property of plasma display technology and is not likely to be eliminated through core technology advancements. The burn-in is caused by a natural degradation of the amount of light output the phosphor chemicals emit as they continue to be “excited” over time, and translates to a “ghost image” when the same image is displayed in the same location for a prolonged period. When a static image like this is displayed, pixels that were “on 100%” (displaying white) would be degrading at the maximum rate while pixels that were “turned off” (displaying black) would not be degrading at all. Over time, after these two groups of pixels were displaying the same color, a noticeable variation in light output for the two groups occurs and the ghost image becomes recognizable.
For Digital Ad Board applications, this characteristic is not too problematic as long as the ad segments that comprise the ad loop represent sufficient variation over the cycle so as to approach a fully dynamic (random) presentation at each pixel of the display. In practice, this would translate to setting a maximum duty cycle of 1% or so for any given image (depending on the native characteristics of the particular plasma display used, the color gradation of the images, the frequency of changes of the ad loop itself, and whether any image spiraling techniques were used to reduce the native burn rate). The net result of a fully dynamic ad loop is that all pixels of the display would degrade roughly the same amount over time, and no ghost effect would be noticed.
For digital signage applications other than Digital Ad Boards (“General Purpose Digital Signage”), the impact of burn-in is far more pronounced. In these applications, at least some portion of the display is not presenting a series of images or video; rather, it would generally include some fixed or pseudo-fixed images that would be present over an extended period of time. For example, as a Flight Information Display in an airport or as a Digital Menu Board in a quick service restaurant, there are generally fixed text fields and frequently fixed text that would be displayed; generating random location patterns is simply not practical in most cases. For these applications, the effect of burn-in becomes dramatic and, in many cases, would prevent the use of plasma technology. Furthermore, eliminating plasma display technology from consideration limits the use of digital displays at all in many of these applications since there are currently no other practical alternatives.
In order to reduce the rate of burn, some plasma manufacturers have incorporated electronics that periodically shifts the image around in a spiral or other pattern, usually within a 5 pixel radius. Although this technique reduces the rate of burn-in, it does not eliminate it; additionally, it introduces a noticeable and distracting movement of the screen image which is particularly noticeable when the user is reading text at the time of the movement.
Furthermore, Digital Menu Board applications generally have zero tolerance to down time; if the menu is not visible the patrons cannot effectively place orders and the entire operation can be sidetracked. Given the typical layout of traditional menu boards that include menu lists (critical) and promotional images (non-critical) content, it is possible to construct a system for multiple display installations that can automatically recover from a single-unit hardware failure by redeploying critical information to the remaining display(s). By doing so, this fault-tolerant design addresses the most critical issue currently stifling the conversion to a digital paradigm: what if the hardware fails?
Wayfinding is one specific digital signage application that utilizes interactive plasma (or other large-screen) display technology to deliver facility directory and other relevant information services. As described in the related U.S. Patent Application Publication Nos. 2002/0078459 and 2002/0165781, the user interface architecture must be conducive to intuitive operation and must blend the generally divergent influences of information and advertising components (when a hybrid advertising/public information model is being used). The marketplace has demonstrated unequivocally that user acceptance of interactive public information systems is paramount to their commercial success, and to date few products of this kind have succeeded even though many have been tried.
Because of the fact that wayfinding users are in a transient mode within a public space, small delays that might be acceptable in a desktop interface may cause the user to disengage in a wayfinding environment. In order to achieve intuitive operation, the interface design must be focused and elements must be carefully chosen so that new users to the system are able to navigate to the desired information quickly and with minimal effort. In order to achieve the desired result, one must focus on three main areas of the interface design:
In view of the foregoing, there remains a need in the art for enhanced display panels and associated apparatus and methodology for driving such display panels.
A visual display including a display installation and a computer is disclosed. The display installation may include a display panel having including a plurality of pixels each with a bit depth and an interface for receiving a video input and for driving the display panel. The computer is configured to determine a primary burn value for each of the pixels for a primary period of time, and to determine a secondary burn value for each of the pixels for a secondary period of time. The computer determines the secondary burn values such that when a pixel is driven at the secondary burn value thereof for the secondary period of time, an average value of the pixel for the primary and secondary periods of time is approximately equal to one-half of the bit depth of the pixel.
In an embodiment, a computer may control or operate a display panel by first determining a primary burn value for each of the pixels in the display panel during an active burn mode. The computer may then identify one of the pixels that has a low primary burn value, thereby indicating that the identified pixel has been burned at a greater degree than pixels having higher primary burn values. The computer may then determine a number of pixels that have primary burn values higher than the low primary burn value, thus indicating that these pixels have been burned at a lesser degree than the identified pixel with the low burn value. The computer may then cause the interface to drive the display panel during a reverse burn mode such that the pixels having a primary burn value higher than the low primary burn value of the identified pixel are burned to reduce the respective differences between higher primary burn values and the low primary burn value.
In yet another embodiment, a computer may control a display panel by monitoring an image history of the pixels during an active burn mode and then identifying a pixel that has been burned at a greater degree than a number of other pixels. The computer may then determine a number of pixels that have been burned at a lesser degree than the identified pixel. The display. panel may then be driven during a reverse burn mode such that the number of pixels that have been burned at a lesser degree are burned to reduce the burn difference between each of the number of pixels and the identified pixel.
Other features and advantages of the display panels disclosed herein will become apparent to those skilled in the art from a consideration of the following detailed description taken in conjunction with the accompanying drawings.
These and other features, aspects and advantages to a visual display panel will be more fully understood when considered with respect to the following specification, appended claims and accompanying drawings, wherein:
Referring to the drawings in more detail, an embodiment of a visual display 100 is illustrated in
According to a number of embodiments, the computer 104 is configured to condition the display panel 106 in response to the video input 112. This panel conditioning feature mitigates uneven burn-in of the pictures where the display panel 106 is not used in an ideal dynamic mode in which all of the pixels are burned at the same rate and intensity. For example and with additional reference to
For the purposes of this description, the primary period of time ΔT1 may be defined as a period of time during which the interface 108 is driving the panel 106 to display a desired or a predetermined video input 112, such as a sequence of advertising images or a sequence of images resulting from an interactive selection (which will be discussed in more detail below). Also for the purposes of this description, the display installation 102 may be described as operating in an active burn mode during the primary period of time ΔT1, which is indicated by reference numeral 116 in
Further, for the purposes of this description, the image history may include data indicative of the color and the intensity of each pixel 110 during the active burn mode 116 of the panel 106. For example, in embodiments in which each of the pixels 110 includes a color set having a plurality of color values each with a bit depth, e.g., red-green-blue (RGB) color values each ranging from 0 to 255, the image history may include data indicative of the each set of color values driving each of the pixels 110. More specifically, the drive signal 114 may include a drive value for each pixel 110, with the drive value including a value for each of the color values, e.g., 128-128-128 for gray, 255-0-0 for red, or 0-0-0 for white. During the active burn mode 116, the interface 108 may drive the display panel 106 such that each of the pixels 110 is driven at a plurality of drive values.
The computer 104, which may include a processor 118 and a memory 120, may then store the image history in a database in the memory 120 (S106). Based on the image history, the computer 104 may then determine a primary burn value B1 (S108). for each of the pixels 110 during the active burn mode 116 (i.e., during the primary period of time ΔT1). In a number of embodiments, the primary burn value B1 for a pixel 110 may be an average value of the pixel during the active burn mode 116.
The computer 104 may then determine a secondary burn value B2 (S110) for each of the pixels 110. The secondary burn value B1 is calculated to complement or even out the burn-in effects the primary burn value B1 had on a respective pixel 110. For example, in a number of embodiments, the second burn value B2 is determined such that when a pixel 110 is driven at the secondary burn value B2 for a secondary period of time ΔT2, an average value of the pixel for the primary period of time ΔT1 (i.e., the active burn mode 116) and secondary period of time ΔT2 is approximately equal to one-half of the bit depth of the pixel, that is:
(B1+B2)÷2=2N÷2, or
B1+B2=2N,
where:
Based on the secondary burn values B2 of the pixels 110, the computer 104 may then generate a conditioning input 122 (S112) and provide the conditioning input 122 to the interface 108. Upon receiving the conditioning input 122 (S114), the interface 108 may then drive the panel display 106 for the secondary period of time ΔT2. For the purposes of this description, the display installation 102 may be described as operating in a reverse burn mode during the secondary period of time ΔT2, which is indicated by reference numeral 124 in
During the reverse burn mode 124, the interface 108 generates the drive signal 114 responsive to the conditioning input 122. After driving the display panel 106 during the reverse burn mode 124 (i.e., for the secondary period of time ΔT2), the interface 108 may then return to the active burn mode 116 and receive another video input 112 (S100). Also during the reverse burn mode 124, the interface 108 drives the display panel 106 to counteract burn-in of pixels 110 during the active burn mode 116 so that each of the pixels 10 degrades or burns out at the same rate, thereby reducing or substantially eliminating ghosts in subsequent active burn modes 116.
For example, in embodiments where each pixel 110 has a RGB color set with a bit depth of 256, if the primary burn value B1 of a pixel 110 is 0-0-0 for a primary period of time ΔT1 of 8 hours, then the secondary burn value B2 of the pixel may be 255-255-255 for a secondary period of time ΔT2 of 8 hours, such that the average value of the pixel for a full duty cycle ΔT1+ΔT2 (i.e., during the active and reverse burn modes 116 and 124) is 128-128-128, wherein the primary and secondary periods of time are approximately equal. Alternatively, if the primary burn value B1 of a pixel 110 is 0-0-0 for a primary period of time ΔT1 of 8 hours, then the secondary burn value B2 of the pixel may be 234-234-234 for a secondary period of time ΔT2 of 16 hours, such that the average value of the pixel for a full duty cycle ΔT1+ΔT2 is still 128-128-128.
In a number of embodiments, the computer 104 may include software stored in memory 120 for use by the processor 118 to carry out the foregoing functionality of the visual display 100. In other embodiments, the computer 104 may be a single-board computer with a graphics card connected to the interface 108.
In still other embodiments, the computer 104 may determine a plurality of secondary burn values B2(1), B2(2), B2(3), . . . , B2(n) for each of the pixels 110 such that when a pixel is driven at the secondary burn values B2 for a corresponding plurality of secondary periods of time ΔT2(1), ΔT2(2), ΔT2(3), . . . , ΔT2(n), an average value of the pixel for the primary and secondary periods of time ΔT1+{ΣΔT2(i) [where i=1 to n]} is approximately equal to one-half of the bit depth. For example, as shown in
The cumulative effect of the plurality of reverse burn modes 124, 126 causes the pixels 110 to have a weight average value of one-half of the bit depth which, in an 8-bit embodiment, is 128-128-128. For example, for a RGB display panel, the interface 108 may drive the panel 106 at a duty cycle of 50% (100-200-150)+25% (152-100-100)+25% (160-12-112), where X%=the duty cycle.
According to a number of embodiments, a visual display 100 may include a plurality of display installations 102 in communication with the computer 104, for example, via a network 128 such as shown in
Regarding the monitoring of the image history (S104), the computer 104 may monitor the drive signal 114 from the interface 108 to the panel display 106. For example, an instantaneous measurement of the drive signal 114 at a given time may be made, with the resulting data stored in the memory 120. In addition, the drive signal 114 may be sampled at a predetermined frequency (e.g., once a second) with the resulting data stored in memory 120.
With reference to
With continued reference to
When the display installation 102 is in normal use during the active burn mode 124, the image-history monitoring process may continue. When the display installation 102 is in the reverse burn mode 126, the data of the image-history database in the memory 120 may be used to determine which of the pixels 110 need to display which colors and for how long in order to effectively reverse or counteract the burn-in effect that has occurred during the active burn mode 124.
One example of the monitoring process is illustrated in
Prior to the start of the monitoring process, each database 134 may be set to “empty,” i.e., all n values are set to 0, and a counter variable is set to 1 (S130). Alternatively, the date and time may be recorded. At the start of the monitoring process, the computer 104 may record the pixel matrix of the display memory 136 into the first database 134a (S132); accordingly, Average-DB is populated with the RGB values from the display memory 136 at that point in time. After a predetermined amount of time, e.g., one second (S134), the computer 104 may record the display memory 136 and store this data in the second database 134b (S136), i.e., Current-DB, with the counter being incremented by 1 (or, alternatively, the current date and time being recorded) (S138).
During the next cycle period, for example, one second (S140), the contents of Average-DB may be re-calculated (S142). For example, for each color field of each record in Average-DB, the corresponding field in Current-DB and the counter may be used to modify each field in Average-DB according to the formula:
NAF={[OAF*(C−1)]+CF}/C,
where:
As shown in
It is possible that after running the reverse burn process for a period of time, all of the fields of Average-DB are not less than 128, at which point the reverse burn mode 126 may stop. However, some of the field values may now be significantly higher than 128 (indicating a dark spot on the display panel 106). These higher values may then be continued in the reverse burn mode 126. Applying 255 to all of the fields that are now at 128 may gradually increase so that entire set towards the peak value. In this case, care would need to be exercised to ensure that the entire display panel 106 is not unnecessarily run in the reverse burn mode 126 (hence shortening the life expectancy thereof) to bring all fields in sync with a small group of pixels.
In embodiments in which the display panel 106 includes a plasma display panel (PDP), different manufacturers utilize plasma crystals whose burn rate differs between red, green, and blue components. Additionally, some manufacturer's electronics dynamically modify the light intensity of displayed pixels depending on the total light output being displayed. In both cases, the computer 104 may accordingly modify or adjust the weighting of the reverse burn values B2 or the conditioning input 122 to take into account these manufacturing variances.
According to a number of embodiments, the display panel 106 may include a combination of critical and non-critical content (such as promotional and menu items in a digital menu board application) as illustrated in
In addition, in the event of a hardware failure of one of the display installations (1, 2, . . . , N) 102, the computer 104 may redeploy critical content onto the display panel 106 of a surviving display installation 102. The computer 104 may utilize a standard interface mode and alternate interface mode(s) in conjunction with peer-to-peer polling mechanisms to trigger the redeployment event.
With continued reference to
In this embodiment, each of the display installations 102 may include a computer 150, an interface 152, and a display panel 154 as shown in
In other embodiments, the computer 104 may automatically change a display layout of one of the display panels of one of the functioning installations 102 to include the critical content of the nonfunctioning installation. For example, with reference to
As mentioned above, according to a number of embodiments, the display panel 106 may include an interactive display panel 140, an example of which is illustrated in
According to still other embodiments, navigation may be further enhanced by introducing feedback/guidance mechanisms throughout navigation of the decision tree. For example, the computer 104 may employ audio and/or visual indicators to reinforce the current location in the decision tree and guide the user on to the next step in the process. In addition, the computer 104 may utilize the content window 144 to display “next step” visual prompts (that is, “Visual Navigation Enhancement,” elements or VNE) in conjunction with relevant audio prompts to guide the user. Categories of VNE elements can be stored and called by the user interface depending on the type of information being displayed and where the user is located within the decision tree structure. For example, a generic “select a store from the list” audio prompt may be one such audio prompt that may coincide with a VNE element. In further embodiments, the VNE element may include a computer animated figure that virtually guides the user on to the next step.
With reference to
According to a number of embodiments, the low primary burn value B1 of the identified pixel may be the lowest value of the primary burn values B1 determined by the computer 104, such that the identified pixel has been burned at the greatest degree out of any of the pixels 110 of the display panel 106 during the active burn mode 116. For the purposes of this description, the term “burn” indicates to activate, operate, or drive a pixel with a drive value or a plurality of drive values for a period of time. In color applications, the drive value may include a plurality of color values (e.g., RGB).
In addition, each of the pixels 110 has a difference between the primary burn value B1 thereof and the low primary burn value B1 of the identified pixel 110. The computer 104 may then cause the interface to drive the display panel 106 during the reverse burn mode 124 such that each of the pixels 110 is burned to reduce the difference between the primary burn value thereof and the low primary burn value of the identified pixel.
Referring to
With further reference to
With further reference to
With particular reference to
With particular reference to
As mentioned above, the interactive user interface 172 may utilize the Content Screen to display visual navigation enhancement (VNE) during decision tree navigation. For example, the visual navigation enhancement may be accomplished via a 3D virtual guide 174. The user interface 172 may include a speaker 176 so that may the virtual guide 174 may include audio coupled to animated speech. In addition, the 3D virtual guide may speak in multiple languages. In these embodiments, the speech may be generated by text-to-speech software. These embodiments may also be implemented as public information systems.
Referencing
With reference to
Referencing
Those skilled in the art will understand that the preceding embodiments of the display panel provide the foundation for numerous alternatives and modifications thereto. These other modifications are also within the scope of the present invention. Accordingly, the display panel is not limited to that precisely as shown and described in the present application.
The present application claims priority under 35 U.S.C. § 119(e) on U.S. Provisional Application for Patent Ser. No. 60/410,539 filed Sep. 12, 2002. In addition, the present application is a continuation-in-part application of and claims priority under 35 U.S.C. § 120 on U.S. patent application Ser. No. 09/943,585 filed Aug. 30, 2001, and on U.S. patent application Ser. No. 10/004,281 filed Oct. 31, 2001. Each of these three prior applications is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60410539 | Sep 2002 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10660818 | Sep 2003 | US |
| Child | 11985164 | Nov 2007 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 09943585 | Aug 2001 | US |
| Child | 11985164 | Nov 2007 | US |
| Parent | 10004281 | Oct 2001 | US |
| Child | 11985164 | Nov 2007 | US |
