OLED display modules for large-format OLED displays

OLED display modules for large-format displays are disclosed. The OLED display module includes a matrix of OLEDs, with each OLED having an anode and a cathode, and an OLED drive circuit having electrical connections defined by rows and columns that electrically connect to the OLEDs in the OLED matrix. Groups of adjacent rows are arranged in parallel and groups of adjacent columns are arranged in parallel, thereby defining super pixels each having an array of four or more OLEDS, wherein the OLEDs in a given super pixel cannot be individually activated. The modules can be combined to form the large-format display.

FIELD

The present disclosure relates to organic light-emitting diodes (OLEDs) and OLED displays, and in particular relates to OLED display modules for large-format OLED displays.

The entire disclosure of any publication or patent document mentioned herein is incorporated by reference, including US 2004/0207315, entitled “Organic light-emitting diode display assembly for use in a large-screen display application,” and US 2005/0017922, entitled “Method for controlling an organic light-emitting diode display, and display applying this method.”

BACKGROUND

Organic light-emitting diodes (OLEDs) utilize a layer of organic luminescent material that, when sandwiched between electrodes and subjected to a DC electric current, produces light of a variety of colors (wavelengths). These OLED structures can be combined into picture elements or “pixels” to form an OLED display. OLEDs are also useful in a variety of applications as discrete light-emitting devices or as the active element of light-emitting arrays or displays, such as flat-panel displays in watches, telephones, laptop computers, pagers, cellular phones, calculators, and the like. To date, the use of OLEDS to form light-emitting arrays or displays has been largely limited to small-screen applications such as those mentioned above.

Demands for large-format displays having higher quality and higher resolution have led the industry to turn to alternative display technologies to replace older LED and liquid crystal displays (LCDs). For example, LCDs fail to provide the bright, high light output, larger viewing angles, and high resolution and speed requirements that the large-format display market demands. Another drawback of conventional LCD's is the fact that the driving interconnections are made from the sides, which precludes efficient tiling of LCD-based display modules. By contrast, OLEDs promise bright, vivid colors in high resolution and at wider viewing angles and so are an appealing option as light sources for large-format displays, such as outdoor or indoor stadium displays, large marketing advertisement displays, and mass-public informational displays.

To date, the use of OLED technology in large-format displays has largely relied upon the same technology used for smaller OLED displays. While this approach is simple and generally sensible, it can also be relatively expensive and not always optimal for the given application.

SUMMARY

An aspect of the disclosure is an OLED display module that includes: a matrix of OLEDs, with each OLED having an anode and a cathode; an OLED drive circuit having electrical connections defined by rows and columns that electrically connect to the OLEDs in the OLED matrix; and wherein groups of i adjacent rows are arranged in parallel and wherein groups of j adjacent columns are arranged in parallel, thereby defining super pixels each having an i×j array of OLEDS, wherein i and j are integers equal to or greater than 2, and wherein the OLEDs in a given super pixel cannot be individually activated.

Another aspect of the disclosure is the OLED display module as described above, wherein the OLED drive circuit has a common-anode configuration, with each column including a current sink and a column switch and each row including a voltage input and a row switch.

Another aspect of the disclosure is the OLED display module as described above, wherein the OLEDs in the matrix of OLEDs emit light of substantially the same wavelength.

Another aspect of the disclosure is the OLED display module as described above, wherein different OLEDs within a given super pixel emit one of a plurality of different colors of light.

Another aspect of the disclosure is the OLED display module as described above, wherein respective OLEDs within a given super pixel emit one of red, green or blue light.

Another aspect of the disclosure is the OLED display module as described above, wherein the colors of light include two or more of red, green, blue, yellow, white, orange, magenta and cyan.

Another aspect of the disclosure is the OLED display module as described above, wherein some of the super pixels are edge super pixels, and wherein at least some of the edge super pixels are inactive.

Another aspect of the disclosure is the OLED display module as described above, wherein some of the super pixels have edge sub-pixels, and wherein one or more of the edge sub-pixels are inactive.

Another aspect of the disclosure is the OLED display module as described above, wherein each of the edge sub-pixels in each super pixel is inactive.

Another aspect of the disclosure is the OLED display module as described above, further including a circuit controller electrically connected to the rows and columns.

Another aspect of the disclosure is the OLED display module as described above, wherein the circuit controller is electrically connected to the rows and columns via a ball-grid-array (BGA) structure.

Another aspect of the disclosure is large-format OLED display that includes a plurality of the OLED display modules as described above, and one or more panels, with each panel operably supporting one or more of the modules.

Another aspect of the disclosure is the large-format OLED display e as described above, wherein the OLED display modules are color modules.

Another aspect of the disclosure is a method of displaying a large-format display image. The method includes: providing a matrix of organic light-emitting diodes (OLEDs); electrically connecting the OLEDs in the matrix of OLEDs to define an OLED display having super pixels, wherein each super pixel includes a group of four or more OLEDs and wherein the OLEDs in each super pixel cannot be activated individually; providing a video signal representative of the display image to the OLED display; and displaying the display image on the OLED display using the super pixels.

Another aspect of the disclosure is the method of displaying a large-format display image as described above, including providing the matrix of OLEDs in multiple modules, and forming the OLED display from the multiple modules.

Another aspect of the disclosure is a method of displaying a large-format display image, wherein different OLEDs within a given super pixel emit one of a plurality of different colors of light.

Another aspect of the disclosure is a method of displaying a large-format display image, wherein respective OLEDs within a given super pixel emit one of red, green or blue light.

Another aspect of the disclosure is a method of displaying a large-format display image, wherein the colors of light include red, green, blue, yellow, white, orange, magenta and cyan.

Another aspect of the disclosure is a method of displaying a large-format display image, wherein some of the super pixels are edge super pixels, and wherein at least some of the edge super pixels are inactive.

Another aspect of the disclosure is a method of displaying a large-format display image, wherein the matrix of OLED are electrically connected in either a common-anode configuration or a common-cathode configuration.

Another aspect of the disclosure is an OLED display module that includes: a matrix of OLEDs, with each OLED having an anode and a cathode, wherein some of the OLEDs constitute edge OLEDs; an OLED drive circuit having electrical connections defined by rows and columns that electrically connect to the OLEDs in the OLED matrix wherein at least some of the edge OLEDs are not electrically connected to the OLED drive circuit; and wherein groups of adjacent rows are arranged in parallel and wherein groups of adjacent columns are arranged in parallel, thereby defining super pixels each having an array of at least four OLEDS, and wherein the OLEDs in a given super pixel cannot be individually activated.

Another aspect of the disclosure is the OLED display module as described above, wherein the OLED drive circuit has a common-anode configuration, with each column including a current sink and a column switch and each row including a voltage input and a row switch.

Another aspect of the disclosure is an OLED display module as described above, wherein the OLED drive circuit has a common-cathode configuration.

Another aspect of the disclosure is an OLED display module as described above, wherein all of the edge OLEDs are not electrically connected to the OLED drive circuit and are not included in any of the super pixels.

Another aspect of the disclosure is an OLED display module as described above, wherein the module includes four edges, and wherein all of the edge OLEDs that reside along at least one of the four edges of the module are not electrically connected to the OLED drive circuit.

Another aspect of the disclosure is an OLED display module as described above, wherein different OLEDs within a given super pixel emit one of a plurality of different colors of light.

Another aspect of the disclosure is an OLED display module as described above, wherein the different colors of light include two or more of red, green, blue, yellow, white, orange, magenta and cyan.

Another aspect of the disclosure is an OLED display module as described above, wherein each super pixel includes edge sub pixels, and wherein at least some of the edge sub pixels in each super pixel are inactive.

Another aspect of the disclosure is an OLED display module as described above, wherein all of the edge sub pixels in each super pixel are inactive.

An advantage of the modules disclosed herein is that the cost of the control electronics is proportional to the display resolution desired and not to the display's highest possible resolution as defined by the OLED matrix. By taking advantage of the physics of combining individual OLEDs on a common device, the amount of drive electronics is reduced and in example can be optimized (i.e., minimized). This is important because when the cost of the drive electronics is based on the highest possible resolution of the device as defined by the OLED matrix and not on the resolution of the final display as defined by super pixels, large-format displays become extremely expensive to the point of being uneconomical.

DETAILED DESCRIPTION

Reference is now made in detail to various embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Whenever possible, the same or like reference numbers and symbols are used throughout the drawings to refer to the same or like parts. The drawings are not necessarily to scale, and one skilled in the art will recognize where the drawings have been simplified to illustrate the key aspects of the disclosure.

The claims as set forth below are incorporated into and constitute a part of this Detailed Description.

Cartesian coordinates are shown in some of the Figures for the sake of reference and are not intended to be limiting as to direction or orientation.

In the discussion below, an A×B array of elements has A elements in the x-direction and B elements in the y-direction, wherein the x-direction represents the horizontal direction and the y-direction represents the vertical direction unless noted otherwise.

Also in the discussion below, a “module” is a display that in an example is configured such that it can be used to form a larger display by the combination of two or more modules, such as by operably supporting one or more modules using one or more panels. Examples of large-format displays that utilize display modules supported by panels are described in U.S. Pat. No. 7,654,878 and in U.S. Pat. No. 6,870,519.

In addition, in the discussion below, the term “sub-pixel” refers to an OLED that constitutes part of a super pixel. An edge sub-pixel is a sub-pixel that resides at the edge of the super pixel.

OLED Display System

FIG. 1is a schematic diagram of an example OLED display system50that includes a large-format OLED-based display assembly (“OLED display”)260, which is described in greater detail below. The OLED display260has dimensions Dx and Dy. In an example, the dimension Dx can be many feet, e.g., greater than 2 feet or greater than 10 feet or even greater than 50 feet. The dimension Dy can have corresponding values consistent with the desired aspect ratio of OLED display260. In the example shown, a cameraman50with a camera52records a video image of people54dancing, and the video image is relayed to OLED display260using conventional means to form an OLED display image56.

In an example, OLED display260is made up of a number of display panels (“panels”)70, such as the 6×5 array of panels shown by way of example. Each display panel70has dimensions d1x×d1y. In an example, the dimension d1xcan range from 450 to 500 mm and the dimension d1ycan range from 250 to 300 mm. In an example, each panel70can be made up of a number of display assemblies or “modules”80, such as the 3×4 array of display modules shown. Each module80has dimensions d2x×d2y. In an example, the dimension d2xcan range from 100 to 150 mm and the dimension d2ycan range from 80 to 120 mm.

FIG. 2Ais a schematic diagram of an example module80that shows in the close-up inset a portion of an OLED drive circuit250as disclosed herein and as discussed in greater detail below.FIG. 2Bis a cross-sectional view of the example module80ofFIG. 2A. The module80has an upper surface81, an edge82, and a lower surface83. In an example, module80is rectangular as shown and edge82is constituted by four edges82a,82b,82cand82d. The OLED drive circuit250includes a circuit controller254(e.g., a microcontroller) and a matrix100M of OLEDs100, each of which has a central light-emitting portion102, as shown in the lowermost close-up inset inFIG. 1. Other electronic components known in the art, such as column registers, shift registers, etc. can be included in OLED drive circuit250but are not shown for ease of illustration. The OLED drive circuit250includes rows r and columns c that represent an x-y grid of electrical connections that electrically connect OLEDs100in OLED matrix100M in a select manner as discussed below.

FIG. 2Bshows an example wherein circuit controller254is electrically connected to row-and-column electrical connections r and c via lower surface83of module80using a ball-grid-array (BGA) structure256.

In an example, OLEDs100have a center-to-center spacing s, which is typically in the range from just over 0.25 mm (e.g., 0.625 mm) to 3.5 mm. In an example, OLEDs100can emit light at one of a number of different wavelengths, such as red (R), green (G), blue (B), white (W), yellow (Y), orange (O), cyan (C), magenta (M) and other colors used in color displays. In some of the discussion below, OLEDs100are assumed to emit a single color of light so that OLED display260is monochromatic, for ease of illustration and discussion of the super-pixel configurations disclosed herein. Example embodiments of a color OLED display260that utilize the super-pixel configurations and OLED drive circuits250disclosed herein are also discussed below. In an example, OLED display260is configured to have high definition.

An advantage of using OLEDs100in module80is that they allow for electrical connections to be made from the back of the module (seeFIG. 2B) rather than from the sides, as is done for liquid crystal display (LCD) panels. This means that the size of an optional bezel (not shown) on the upper surface81of module80can be reduced significantly as compared to that needed for an LCD panel because the bezel for the module would be used only for sealing OLEDs100from the surroundings and not for hiding electrical interconnects. This allows for modules80to be smaller than LCD panels while also reducing adverse effects of the bezels that arise between adjacent modules (e.g., so-called bezel or seam effects).

Conventional OLED Display

FIG. 3is a schematic circuit diagram of a conventional (prior art) OLED drive circuit150as part of a conventional OLED display160. The OLED drive circuit150has a common-anode circuit configuration that allows for activating OLEDs100individually (i.e., the OLEDs are independently addressable). The OLED drive circuit150can also have a common cathode configuration, as is known in the art. In the example shown, OLED display160has eight columns and six rows of OLEDs100(i.e., is an 8×6 display), for a total of 48 OLEDs that define OLED matrix100M.FIG. 3includes numbers in italics that denote the matrix position (row and column) of OLEDS100, e.g.,11indicates the OLED in the first row, first column in the array, while46indicates the OLED in the fourth row, sixth column in OLED matrix100M. Advantages of the common-anode configuration as compared to the common-cathode configuration include that for the former, the circuitry becomes more independent of the drive voltage. In the case of the common-cathode configuration, the drive voltage variations can have an effect on the current flowing through an OLED100and hence have an impact on the light output. In the common-anode configuration, the reference is ground G, which is by definition much more stable.

Commercially available displays can have many thousands of individual OLEDs100, which are available in different formats, colors, sizes and other attributes. Each OLED100has a cathode102and an anode104. The OLED drive circuit150includes an x-y grid of conductive lines or wires represented by columns c (e.g., c1through c8) and rows r (e.g., r1through r8). The cathode102and anode104of each OLED100is respectively electrically connected to a given row r and a given column c.

The OLED drive circuit150also includes current sinks CS (e.g., CS1through CS8) arranged at an end of the respective columns c (e.g., columns C1through C8), followed by ground switches SG (e.g., switches SG1through SG8). Each row r includes a (row) switch SR (e.g., switches SR1through SR6). The OLED drive circuit150also includes bank voltage inputs VB (e.g., VB1, VB2, . . . VB6) for rows r. The bank voltage inputs VB reside adjacent switches SR.

Each OLED100emits light when a current passes from its anode104to its cathode102. As an OLED100is a current-sensitive device, the current needs to be controlled to get the light output required without damaging the device. In an example, an OLED100and a current-limiting device such as a resistor (not shown) can be placed in a series circuit configuration. A voltage of higher potential is applied to the circuit closest to anode104and the other end of the series circuit is connected to a lower voltage potential. The difference in the voltage potential has to be high enough to overcome the threshold voltage of OLED100. By adjusting either the resistance in series with OLED100or the voltage applied across the OLED and the resistor, the current can be set to generate the required light output for the given application.

For many designs, the lower voltage potential is set at ground level and the higher potential is a positive power supply. Instead of a simple resistor, current sinks CS are used, as shown inFIG. 3. The current sinks CS are well known to practitioners in the electrical arts and use an active circuit to control the current flowing through the branch. In this manner, the operation is less sensitive to changes in supply voltage or changes in OLEDs100.

With continuing reference toFIG. 3and as noted above, OLED drive circuit150is configured such that each OLED100in OLED matrix100M can be activated individually. For example, to activate OLED100at position11, a positive voltage is applied to voltage input VB1, a ground potential (i.e., ground G) is connected to current sink CS1, switch SR1is turned on (i.e., is closed) and switch SG1is also turned on. This causes current to flow from the positive voltage at VB1, through switch SR1, through OLED100at position11, through current sink CS1, through switch SG1and then to ground G, as indicated by the leftmost arrow AR.

Multiple OLEDs100in the same row r can be activated at the same time. While switch SR1is active, any or all of the switches SG1through SG8can be activated. In this manner, the entire OLED display160can be activated one row r at a time by activating switches SR1through SR6one at a time while activating switches SG1through SG8such that OLEDs100are selectively illuminated. It is noted that multiple rows r cannot be activated at the same time since the current sinks CS1through CS8have been set to the current required by a single OLED100. If two rows r of OLEDs100were activated, the current to those OLEDs in the activated columns c would be half of that required to activate OLEDs in a single row. This would reduce the amount of light emitted from OLEDs100.

OLED Display with Super Pixels

FIG. 4Ais a schematic diagram of OLED drive circuit250as part of OLED display260as disclosed herein. The OLED drive circuit250has a modified common-anode circuit configuration. In another embodiment not shown, the OLED drive circuit250can have an analogous modified common-cathode configuration. The common-anode configuration has some advantages as described above and so is shown and discussed herein by way of illustration.

The OLED display260includes an 8×6 matrix100M of OLEDs100, with the dashed lines indicating groupings of adjacent OLEDs and with each grouping defining what is referred to herein a “super pixel”300, wherein each OLED100in given super pixel constitutes a sub-pixel for that super pixel. The example OLED drive circuit250has a common-anode configuration but has half the number of switches SG and SR and half the number of current sinks CS.

The electrical connections or wires defined by rows r and columns c are arranged so that OLEDs100in each super pixel300can only be activated together, i.e., the OLEDs are no longer individually addressable. In the example OLED drive circuit250ofFIG. 4A, rows r1and r2are electrically connected, rows r3and r4are electrically connected and rows r5and r6are electrically connected. Similarly, columns c1and c2are electrically connected, columns c3and c4are electrically connected, columns c5and c6are electrically connected, and columns c7and c8are electrically connected.

The super pixels300of OLED display260ofFIG. 4Aare four times larger than the OLED pixels of the conventional OLED display160ofFIG. 3. In an example, each OLED100(sub-pixel) in a given super pixel300can have substantially similar electrical and visual characteristics (e.g., a substantially similar emission wavelength) and share current when connected in a parallel fashion. In another example, OLEDs100in a given super pixel300can have at least one substantially different characteristic, such as different emission wavelengths.

With the super-pixel configuration for OLED matrix100M of OLED display260, the number of active electrical components in OLED drive circuit250is reduced as compared to the prior art OLED drive circuit150ofFIG. 3. In the example shown inFIG. 4A, the OLED drive circuit250has gone from six switches SR for the positive supply to three, eight current sinks CS to four and eight ground switches SG to four. Overall, the number of active control elements has been reduced from twenty two to eleven. This reduction in active control elements scales with the size of OLED display260.

Generally speaking, for a conventional OLED display160that includes p×q OLEDs100as pixels such as shown inFIG. 3, the “conventional” number NCof active electrical components is given by NC=2p+q. Thus, for the example OLED display150ofFIG. 3, p=8 and q=6, so that NC=2(8)+6=22. For an OLED display260that includes m×n super pixels300, the number NSPof active electrical components is NSP=2m+n, which in the 4×3 example ofFIG. 4Ais NSP=2(4)+3=11. The reduction or change Δ in the number of active electrical components is given by Δ=NC−NSP, which is for the present example, Δ=11, which represents a 50% reduction in the number of active electrical components.

Because each activated super pixel300in the example OLED matrix100M ofFIG. 4Ais four times as large as an individual OLED pixel, the capacity of the positive switches SR, current sinks CS and ground switches SG all need to handle four times the amount of current. However, the active control elements can be judiciously selected so that the scaling of the power capacity is not a substantial cost factor.

The number of active electrical components for the example ofFIG. 4Bis given by NSP=2n+m=2(2)+3=7, so that the reduction in the number of active electrical components is Δ=22−7=15, or about a 68% reduction.

Because each super pixel300in the example ofFIG. 4Bis eight times as large as an individual sub-pixel defined by OLED100, the capacity of the positive switches SR, current sinks CS and ground switches SG all have to handle eight (8) times the amount of current. As noted above in connection withFIG. 3, the active control elements can be judiciously selected so that the scaling of the power capacity is not a substantial cost factor.

In general, OLED drive circuit250as disclosed herein is configured to define super pixels300that consist of i×j OLEDs100by electrically connecting i adjacent columns and j adjacent rows for each super pixel. Any reasonable number of OLEDs100can be used to constitute a super pixel300, and in an example the smallest super pixels can be 2×2. In an example, the size of super pixels300is selected based on OLED display260having high-definition resolution. An example high-resolution OLED display260can have for example 1280×720 super pixels300or 1920×1080 super pixels, as defined by OLED drive circuit250disclosed herein.

FIG. 5is a close-up view of a portion of an example module80wherein each super pixel300includes red (R), green (G) and blue (B) OLEDs100so that the super pixels are color pixels and OLED display260is a color display. The super pixels300can other colors as well, such as those mentioned above

Modules with Color Super Pixels

FIG. 6Ais an elevated exploded view of an example color module80C that shows R, G and B monochrome modules80R,80G and80B arranged in a layered configuration. The R, G and B monochrome modules80R,80G and80B respectively include R, G and B OLEDs100, denoted100R,100G and100B, respectively. Other colors for the monochrome modules80can be used (e.g., white W, yellow Y, orange O, cyan C and magenta M) and the R, G and B colors are selected here merely for the sake of illustration and because R, G and B are common display colors.

The R, G and B monochrome OLED displays260R,260G and260B include respective super pixels300R,300G and300B, which are respectively made up of OLEDs100R,100G and100B. In the example shown inFIG. 6A, super pixels300R,300G and300B are each 4×3, as illustrated in the close-up insets.

It can be noted that R, G and B super pixels300R,300G and300B need not be activated at the same time. In an example, one of the super pixels300, such as the red super pixels300R, can be driven all in parallel, while the other super pixels, such as the G and B super pixels300G and300B, can be driven individually. In one example, the R, G and B super pixels300R,300G and300B are activated at the same time, i.e., are driven simultaneously.

FIG. 6Bis a close-up cross-sectional view of a portion of the example color module80C ofFIG. 6A. The layered configuration is made possible by the fact that the individual monochrome modules80R,80G and80B are substantially transparent. The OLED displays260are formed using a screened electronics process wherein the individual OLEDS can have nearly identical light output characteristics given the same electrical stimulus. The OLED displays260are commercially available in different resolutions, colors, and sizes and with other features, depending on the needs of the final application.

The monochrome red, green and blue modules80R,80G and80B are configured so that the respective super pixels300R,300G and300B emit R, G and B light generally in the z-direction through an upper surface81C of color module80C. In an example, super pixels300R,300G and300B are offset in the x-y plane as shown. In an example, triplets of super pixels300R,300G and300B define color super pixels300C.FIG. 6Cis an elevated, exploded view of an example color super pixel300C of color module80C.

OLED Display with Dark Super Pixels or Dark OLEDs

FIG. 7Ais a front-on view of an example module80made up of 234 super pixels300in an 18×13 configuration. The module80includes outer edges82a,82b,82cand82dat which reside edge super pixels300e, respectively denoted300ea,300eb,300ecand300ed.FIG. 7Bis similar toFIG. 7Aand shows edge super pixels300eas inactive or dark super pixels.FIG. 7Cshows an example panel70made up of modules80ofFIG. 7Bhaving dark edge pixels300ea,300eb,300ecand300ed.FIG. 7Dis similar toFIG. 7Cand shows an example where for adjacent modules80, only one row and/or column of edge super pixels300eare dark super pixels.

FIG. 8Ais a close-up, front-on view of an example panel70that shows two adjacent modules80and a seam84that resides between the modules. The modules80each include super pixels300in a 4×3 configuration. InFIG. 8A, only edge super pixels300eare shown for ease of illustration. In the example panel70, for the edge super pixels300ecand300eahat define seam84, the most edgewise OLEDs100in the edge super pixels are inactive or dark super pixels. Thus, rather than having all of OLEDs100of edge super pixel300ebeing dark (so that the entire edge super pixel is dark), only the edge OLEDs, denoted100ecand100ea, are dark or inactive. Note that this same technique can be used for seams84that are horizontal, with the corresponding edge OLEDs100edand100ebbeing inactive.

The inactive or dark edge OLEDs100ecan be formed by not connecting the OLEDs to a row r or column c in OLED drive circuit250. In another example, the inactive or dark edge OLEDs100ecan be formed by having them electrically connected with the rows r and columns c but programming circuit controller254to recognize the edge OLEDs and to provide a bank voltage VB suitable for preventing select edge OLEDs from emitting light (e.g., holding the bank voltage VB high to prevent current flow through the edge OLED). In a similar manner, entire edge super pixels300eof a given module80can be made dark by programming circuit controller254to selectively activate only those super pixels300that do not reside next to super pixels of an adjacent module. In the case ofFIG. 7D, circuit controller254can be programmed to ensure that only one column c or row r of edge super pixels300ethat reside adjacent seam84are inactive.

FIG. 9Ais a front-on schematic diagram of an example module80having a 64×48 OLED matrix100M of OLEDs100, with 4×4 super pixels300, so that the module has 16×12 super pixels. The module80includes edge OLEDs100eor edge sub-pixels (i.e.,100ea,100eb,100ecand100ed) that are inactive or dark and that do not belong to any of super pixels300. An example module80has at least one of edge OLEDs100ea,100eb,100ecand100edas dark or inactive edge OLEDs (i.e., the module has one or more dark edges82a,82b,82cand82d).

FIG. 9Bis a close-up view of portions of two adjacent modules80wherein edge OLEDS100ecof the left-side module and edge OLEDs100eaof the right-side module are inactive or dark, and wherein both of these edge OLEDs do not belong to any of super pixels300. In an example, the dark edge OLEDs100eare dark or inactive by virtue of not being electrically connected to OLED drive circuit250.

One reason for having dark edge pixels300eis to improve the overall resolution of OLED display260. Typically, modules80that make up OLED display260are formed on a glass substrate. In some examples, the thickness of the glass substrate creates illumination issues at seams84between adjacent modules80that give rise to undesirable visual effects when a display image is viewed. Consequently, it can be advantageous to have no light emission from either edge super pixels300eor edge OLEDs100eat seam84or the interface between adjacent modules80.

It will be apparent to those skilled in the art that various modifications to the preferred embodiments of the disclosure as described herein can be made without departing from the spirit or scope of the disclosure as defined in the appended claims. Thus, the disclosure covers the modifications and variations provided they come within the scope of the appended claims and the equivalents thereto.