Segmented OLED with patterned buslines

Abstract

This invention provides an OLED device comprising an array of bottom-emitting OLED segments, each bottom-emitting OLED segment having a bottom electrode segment, a top electrode, and an organic layer for emitting light, separated by a non-emitting gap. The bottom electrode of each segment has an individual power feed line that may be opaque. At least one individual power feed line for another OLED segment is disposed within the emission light path of a first OLED segment. The power feed lines positioned within the emission light path are portions of a visible pattern of uniformly spaced parallel lines of constant width. The visible pattern may include a non-electrically connected extension associated with each power feed line, which together form a visiblely continuous extension. The visible pattern may include additional pattern lines. The visible regular pattern is not easily perceptible or obvious to the human visual system.

Description

Prior Technology

[0001] LED and OLED lighting panels offer numerous advantages for general lighting purposes. They are highly efficient in terms of light output and power consumption. They operate at low voltage, which helps avoid potential electric shock, is less likely to spark in potentially explosive environments, and reduces the load on supporting electrical systems. The spectrum of emitted light can be varied using appropriate internal design. They produce very little or no UV or IR light. They are instant-on; that is, they emit light immediately whenever electrical power is supplied.

[0002] LED light sources are inherently small point sources, and to function as a flat, general-purpose lighting source, numerous individual LED devices must be connected together. This increases manufacturing costs and complexity. The uniformity of the light surface must be controlled through proper design. LEDs generate some heat, and therefore heat sinks or other thermal control measures are typically used. Practical LED lighting panels can be manufactured very thin, for example, from 3 mm to 16 mm, using appropriate system design.

[0003] OLED light sources are inherently flat-area light sources. They offer several advantages over LED lighting panels. They can be manufactured thinner (e.g., less than 1 mm thick) and generate very little heat under normal operating conditions. However, OLED lifespan can be an issue. Both LED and OLED lighting panels can be manufactured on flexible or curved substrates, but OLED is better suited for these types of applications.

[0004] In summary, both LED and OLED devices can be used as lighting panels. Both are highly efficient, low-voltage, cool to the touch, and thin.

[0005] For some applications, multiple independently controlled individual OLED or LED devices can be mounted on a single substrate to provide a "mounted" device. In this application, each individual OLED or LED light source (excluding electrical connections) (including its own substrate) is pre-fabricated and independently, and mounted side-by-side or in an array. Such devices can provide variable general-purpose lighting (i.e., by supplying power to individual units according to the desired total light intensity) or a low-resolution communication device (i.e., by supplying power to individual units in a pattern). OLED panels are generally advantageous for this purpose because OLEDs can have a larger emitting area than a single LED. This provides a generally desirable larger fill factor (total emitting area). To provide a larger emitting area with LED light sources, multiple LEDs sharing the same power supply must be used in the same area. This increases manufacturing complexity and cost, and without the use of diffusers (which reduce light output efficiency and reduce sharpness and contrast at the edges of the emitting area), a uniform appearance is not provided.

[0006] For other applications, multiple independently controlled individual OLED devices can be directly fabricated on a single common substrate to provide a "segmented" OLED device. Non-emitting gaps or spaces exist between the individual segments. The surface area of ​​each individual segment corresponds to the illumination area and is typically surrounded by a non-illuminating boundary region along the outer edge of the substrate. These segmented OLED light sources offer manufacturing and cost advantages because multiple layers can be shared across all individual units without the need to handle or install separate OLED panels. Because LEDs must be individually fabricated on their own substrates, it is impossible to fabricate a true segmented LED device where all LEDs share a common internal substrate. Segmented OLED devices can provide variable universal lighting or a low-resolution communication device.

[0007] Segmented OLED devices are particularly well-suited for automotive exterior lighting applications (such as taillights) because, unlike LED devices, they do not require additional reflectors, light guides, or additional optics to produce homogeneous surface light. See, for example, M. Kruppa et al., Information Display 4 / 19, pp. 14–18 (2019). Furthermore, applications such as automotive taillights typically require some degree of visibility from the sides and directly from the rear; therefore, taillight assemblies often have a complex design involving a mixture of curved and relatively flat surfaces. Segmented OLED devices can be fabricated on flexible substrates, simplifying design considerations in a non-planar taillight assembly. However, automotive taillight assemblies are an internal part of the overall exterior appearance of a vehicle and must provide a smooth and compatible design and appearance.

[0008] Generally, OLED devices are formed on a substrate and can be top-emitting (light emitted from a surface opposite the substrate) or bottom-emitting (light emitted through a transparent substrate). To create individually controlled OLED segments, at least one electrode must be segmented; that is, the electrode of one OLED segment is electrically isolated from a corresponding electrode in a different OLED segment. In this way, the emission from each OLED segment can be individually controlled by a single, dedicated power feed line to one electrode segment.

[0009] While both top-emitting and bottom-emitting OLEDs are suitable for automotive applications, bottom-emitting OLEDs are preferred for at least two reasons. First, external applications require robust encapsulation. This is more difficult to achieve with the transparent encapsulation required for a top-emitting OLED, especially when the OLED (and therefore the encapsulation) must be flexible. A bottom-emitting OLED can use a very robust encapsulation because the encapsulation on the non-emitting side does not need to be transparent. Second, the OLED will be positioned in a confined space where heat accumulation can be problematic. A bottom-emitting OLED allows a heat sink to be positioned on the back side. With a top-emitting OLED, the heat sink is positioned on the opposite side of the substrate, which reduces the heat transfer rate and therefore cooling is inefficient.

[0010] Each segment in a segmented OLED device requires a separate power feed (also referred to as a power line, busline, metal trace, conductive trace, lead, or current trace), which presents several design challenges. If the power feed is positioned in the emission path below the active region of the OLED segment, it can be visible due to light absorption or scattering. This is undesirable. Specifically, in a bottom-emitting OLED, positioning the power feed directly on a transparent substrate, either below or above the transparent bottom electrode and below the organic layer, can be problematic. Furthermore, depending on its reflectivity, it can be visible even when the segment is cut off and not emitting, because incident light enters the OLED and is reflected from the power feed. The visibility of the power feed at any time will detrimental to the smooth and uniform appearance of the segmented OLED device.

[0011] This problem is illustrated in Figure 1, a top view photograph of a prior art bottom-emitting segmented OLED device in which power feeds are positioned under electrode segments and in the light emission path. In this particular example, individual OLED segments are configured in an array of triangles and hexagons, with non-emitting gaps between them. The underlying individual power feeds are made of ITO and operate directly under the OLED segments and in the light emission path. The power feeds are laterally separated from each other and separated from the overlying electrode segments by an insulating layer of SiO2. In this configuration, the non-linear and non-uniformly spaced ITO power feeds are clearly visible even when partially transparent, and the entire segmented OLED device does not have a smooth and clean appearance.

[0012] Figure 1 shows a segmented OLED device in a non-emitting, unlit state. The ITO power feed line is visible because ambient light can pass through the transparent substrate, the partially transparent power feed line, the partially transparent bottom electrode (also made of ITO), and bounce off the reflective top electrode and return through other structures and the substrate. Because some of the light is absorbed by the power feed line, it becomes visible. In an operational emitting (lit) state, the power feed line may be visible or invisible, depending on the emission level and viewing distance. In either case, a visible power feed line is undesirable, but its relative importance will depend on the specific application.

[0013] Power feeders are typically made of conductive materials and must be sufficiently conductive to supply power over a distance (which can be relatively long in some cases (e.g., internally segmented)) without a significant IR (current × resistance or voltage) drop attributable to resistance. This can result in uneven brightness. Generally, the amount of IR drop is inversely proportional to conductivity, which, for any given material, is controlled by its thickness (height), width, and length. In many cases, even if the material is mostly transparent, the required thickness and width to provide sufficient conductivity can make the power feeder visible. If it is thin enough to be almost invisible, the power loss attributable to the IR drop can be large and unacceptable. To avoid IR drop, power feeders made of highly conductive metals would be desirable; however, metal power feeders would generally need to be thick enough to be completely opaque, but in some cases, they can be translucent and partially transparent. In either case, metal power feeders will be visible if positioned in the emission path. The IR drop along the power feed line is important regardless of the distance from the external power source or the size of the OLED segment (larger segments require more operating power than smaller segments). However, the IR drop can be minimized by adjusting the width (parallel to the substrate) or height (above the substrate) of the power feed line.

[0014] For this reason, the power feed is expected to be positioned in the non-emitting gaps between the individual OLED segments, so that the power feed is not visible at least when the OLED segments are emitting and the gaps will appear dim. Typically, the width of the non-emitting gaps between the individual OLED segments will be consistent to provide a uniform appearance and will be as thin as possible to maximize the emission area.

[0015] However, positioning the power feeders within the non-emission gaps between OLED segments presents a problem. First, all power feeders (one for each individual OLED segment) must be separate and electrically isolated from each other, allowing each segment to be independently controlled and free from short circuits. Depending on the configuration of the OLED segments and the width of the gaps, it is impossible to place all the required power feeders within the limited area of ​​the non-emission gaps unless the feeders traverse each other without contact. This significantly increases manufacturing costs. Second, the power feeders for OLED segments along or near the edge of the device are relatively short, while those for the OLED segments inside the device are relatively long, especially when the path of the power feeders is confined by the gaps between the segments. Assuming a common power source, the power delivered by a longer power feeder is less than that delivered by a shorter power feeder due to its increased resistance (IR drop). This can lead to uneven emission, where the inner segments have lower emission than the segments along the edge of the device. For this reason, the power feeds leading to the internal OLED segments need to be relatively large (to reduce resistance) and the spacing between them need not be wide enough to allow for multiple large power feeds. For these reasons, it is impractical to typically position all power feeds in the gaps between OLED segments.

[0016] To avoid these issues, many previous methods for segmented OLED devices were based on top-emitting OLED formulations where the power feed lines were not visible. However, it would still be desirable to position the power feed lines on the substrate in a segmented bottom-emitting OLED device, such that any power feed lines located within the emission path of an individual OLED segment are invisible or at least not very noticeable or perceptible.

[0017] This is described in WO2022 / 250995 as a segmented OLED device in which a segmented power feed line is arranged within the light emission path. The visibility of the power feed line is reduced by including at least one refractive-reducing material in contact with it. However, this method is not suitable for opaque metallic power feed lines located within the light emission path.

[0018] This is jointly described in WO2023 / 224594 as a segmented OLED device having an internal passive capacitor structure. Power feed lines to the segments can be configured within the emitted light path.

[0019] Bechert et al.’s “Flexible and highly segmented OLED for automobile applications” (SPIE proceedings, Vol. 10687, SPIE Photonics Conference 2018) describes a top-emitting OLED in which the bottom electrodes of each segment are electrically connected to metal traces located on a substrate via a polymer insulating layer that separates the two.

[0020] US9048450B2 describes the use of a current distribution line that contacts the interior of a first electrode and is positioned above a second electrode and is not in the emission path.

[0021] US20140326983A1 describes an OLED in which bus lines are positioned above or between anode segments. These are not positioned between the anode segments and the substrate. US 9,583,731 relates to an auxiliary electrode positioned in a trench outside the light path.

[0022] Other references describing the power feed lines in a bottom-emitting segmented OLED include US8309977B2, US8432095B2, US10888002B2, US8927309B2, US8653509, US2017 / 0207411, US9692005, US10141535, US8941143, US9487878, US9159945, US7408296, US10068958, US9627643, US2006 / 0108915, US7336036, JP2002075662 and US20190363155.

[0023] It is known that internal structures configured as a periodic pattern can improve light scattering or reduce surface plasma formation in OLEDs. Examples include: US10581029B2; DE102011076733A1; JP2017162616A; US8541778; US20120132897; US8710527B2; and US9203054B2. However, these structures are neither conductive nor function as power feeds.

[0024] Other references include: A. Salehi et al., “Recent Advances in OLED Optical Design”, Adv. Funct. Mater., 29, 1808803 (2019); Y. Qian et al., “Human Eye Contrast Sensitivity to Vehicle Displays under Strong Ambient Light”, Crystals, 13, p. 1384 (2023); YJ Kim and Hs. Kim, “Spatial Luminance Contrast Sensitivity: Effects of Surround”, Journal of the Korean Optical Society, 14 (2), pp. 152-162 (2010); E. Langendijk and M. Hammer, “14.4: Contrast Requirements for OLEDs and LCDs Based on Human Eye Glare”, SID Conference Abstracts, 41 (1), pp. 192-194 (2010); J. Ko et al., “An Effective Quantification Method for Evaluating Horizontal”. "Line Defects by Interference between Flexible OLED and Touch Sensor", SID Symposium Abstracts, 52 (1), pp. 1346-1349 (2021); and "Correcting for Optical Aberrations using Multilayer Displays" by FCHuang et al., ACM Graphics Journal, Vol. 31 (6), Article 185 (2012). Summary of the Invention

[0025] To reduce the visibility of opaque power feeds located within the emission path, it is desirable for the power feeds within the emission path to be configured as a portion of a visible pattern of uniformly spaced parallel lines of constant width extending continuously across the active region from one OLED segment to another within the array. This regular pattern is less noticeable or more obvious than a broken or irregular pattern.

[0026] Some key features include an OLED device comprising: an array of bottom-emitting OLED segments disposed on a common transparent substrate, each individual OLED segment being separated by a non-emitting gap; wherein each OLED segment has an active region defined by a transparent bottom electrode segment, a top electrode, and an organic layer for light emission between the top electrode and the bottom electrode segment, wherein the bottom electrode of each segment is electrically connected to a separate power feed line; such that for at least one first OLED segment (S1), there is at least one separate power feed line for another OLED segment that is not electrically contacted with the first OLED segment (S1) and is disposed within the light emission path of the first OLED segment (S1); wherein the power feed line of the other OLED segment located within the light emission path of the first OLED segment (S1) is at least a portion of a visible pattern comprising uniformly spaced parallel lines (50, 51) of a constant width that appear to extend continuously across the active regions of the first (S1) and at least one other OLED segment.

[0027] As described in the aforementioned OLED device, at least one of the parallel lines of the visible pattern includes: a first line segment which is a separate power feed line; and a second line segment which is an extension line; the extension line is electrically isolated from the power feed line in the first line segment, such that the first and second line segments together form a straight line that appears to be continuous in a visible manner.

[0028] As in any of the aforementioned OLED devices, at least a portion of the visible pattern includes at least one additional pattern line that is separated from and electrically isolated from any of the individual power feeds.

[0029] As in any of the aforementioned OLED devices, the extension lines (50a, 56, 58, 60a, 62a) of the visible pattern are positioned above the substrate in the same plane as the power feed lines (P1, P2, P3...), have the same composition as the power feed lines (P1, P2, P3...), and have the same width as the power feed lines (P1, P2, P3...).

[0030] As in any of the aforementioned OLED devices, all individual power feed lines and additional pattern lines within the array are opaque. These individual power feed lines may include layers of chromium and aluminum.

[0031] As in any of the aforementioned OLED devices, at least two of the lines of the visible pattern extend from one edge of the emitting region of the array to the opposite edge, such that the lines of the pattern are visible in the emission of all OLED segments along the lines.

[0032] As in any of the aforementioned OLED devices, there are two or more overlapping visible patterns with uniformly spaced parallel lines of constant width, wherein the uniformly spaced parallel lines of each pattern are set to form an angle with each other.

[0033] As in any of the aforementioned OLED devices, the visible pattern of uniformly spaced parallel lines of constant width is superimposed on at least 70% of the total emitting area of ​​the array. There may be a primary visible pattern and one or more secondary visible patterns of uniformly spaced parallel lines of constant width, wherein the primary pattern is superimposed on at least 51% of the total emitting area of ​​the array. The primary pattern may be positioned at the center of the array, and all the secondary patterns are positioned within 20% of the total distance from the emitting region of the array to the nearest edge.

[0034] As in any of the aforementioned OLED devices, there is a power feed line for positioning at least one OLED segment within the non-emission gap. At least one of the parallel lines (50, 51) of the visible pattern may be positioned within the non-emission gap, the line within the non-emission gap comprising: a first line segment which is a separate power feed line; and a second line segment which is an extension line; the extension line is electrically isolated from the power feed line in the first line segment, such that the first and second segments together form a visiblely continuous straight line.

[0035] As in any of the aforementioned OLED devices, the parallel lines are spaced apart by a distance (d) ranging from 0.05 mm to 10 mm. As in any of the aforementioned OLED devices, the width of the parallel lines is ranging from 0.005 mm to 1 mm. Simple Explanation of the Diagram

[0036] Figure 1 is a top view photograph of a prior art bottom-emitting segmented OLED device, in which power feed lines located below the electrode segments and in the light emission path leading to the individual OLED segments are visible.

[0037] Figure 2A is a top view of a prior art segmented OLED device 100 in a non-operational, unlit state. Figure 2B shows the same view of 100 in an emission-lit state. Figure 2C shows a cross-sectional view along edge 1 (as indicated in Figures 2A and 2B).

[0038] Figure 3A shows a view of one of the segmented OLED devices 200 of the present invention in an unlit state. Figure 3B shows the same view of 200 when it is lit. Figure 3C shows a cross-sectional view along line xy of 200 indicated in Figure 3A. Figure 3D shows a cross-sectional view along line x'-y' of 200 indicated in Figure 2A.

[0039] Figures 4A (unlit) and 4B (lit) show a top view of one of the segmented OLED devices 300 of the present invention.

[0040] Figures 5A (unlit) and 5B (lit) show a top view of one of the segmented OLED devices 400 of the present invention.

[0041] Figures 6A (unlit) and 6B (lit) show a top view of one of the segmented OLED devices 500 of the present invention.

[0042] Figure 7 shows a partial top view of a section of an OLED array (not lit) from the emitting side.

[0043] Figures 8A (unlit) and 8B (lit) show one view of a segmented OLED device 600 of the present invention.

[0044] Figures 9A (unlit) and 9B (lit) show a top view of the emitting bottom side of a segmented OLED device 700 of the present invention.

[0045] Figures 10A (unlit) and 10B (lit) show a top view of one of the segmented OLED devices 800 of the present invention.

[0046] Figures 11A (unlit) and 11B (lit) show a top view of a segmented OLED device 900 of the present invention. Figure 11C shows a cross-sectional view along edge 1 (indicated in Figure 11A) of 900 (unlit). Figure 11D shows a cross-sectional view along edge 2 (indicated in Figure 11A) of 900 (unlit).

[0047] Figure 12A illustrates the Poggendorff illusion. Figure 12B illustrates one possible adjustment to avoid the Poggendorff illusion effect.

[0048] Figure 13 shows a schematic cross-sectional view of one or two stacked OLED formulations 1000.

[0049] The figures are for illustrative purposes only and are not to scale. All top views of the device are taken from the (bottom) emitting side of the device (i.e., the transparent support side). All cross-sectional views are drawn with the transparent substrate on the bottom side of the view, not the top side (which will be aligned with the orientation of the top view). This does not alter the internal structure or any relationship to details in the description. Implementation

[0050] [Cross-reference to related applications] [] Refer to the joint assignment PCT application PCT / US2022 / 029413 entitled "SEGMENTED OLED WITH ELECTROSTATIC DISCHARGE PROTECTION" filed on May 16, 2022, and the joint assignment PCT application PCT / US2022 / 029409 entitled "SEGMENTED OLED" filed on May 25, 2021, claiming the rights of U.S. Provisional Application No. 63 / 192,942.

[0051] For the purposes of this invention, the terms "above" or "over" mean that the structure in question is positioned above another structure, i.e., on the side opposite to the substrate. "Uppermost" or "above" refers to the side or surface furthest from the substrate, while "lowest" or "below" refers to the side or surface closest to the substrate. Unless otherwise specified, "above" should be interpreted as two structures being in direct contact or an intermediate layer existing between them. "Layer" should be understood as a layer having two sides or surfaces (a topmost and a bottommost) and multiple layers may exist, not limited to a single layer. "LEL" always refers to a single light-emitting layer. "Unit" generally refers to a minimum portion of a layer, which can be considered as acting as a single light source; a unit can be equivalent to a single LEL, may contain one LEL associated with other non-emitting layers, or may have multiple LELs with or without additional layers. A light-emitting unit is a group of one or more LELs separated from another light-emitting unit by a charge-generating layer (CGL). Therefore, if an OLED device does not have a CGL, there is no light-emitting unit, but it may have multiple LELs. This device is typically referred to as a "stacked" device. If an OLED device has two light-emitting units separated by a CGL, it can be referred to as a "double-stacked" device. A stacked OLED can have multiple units or combinations of units and LELs that together form a total emission.

[0052] R indicates a layer or unit that primarily emits red light (>600 nm, ideally in the range of 620 nm to 660 nm), G indicates a layer or unit that primarily emits green light (500 nm to 600 nm, ideally in the range of 540 nm to 565 nm), and B indicates a layer or unit that primarily emits blue light (<500 nm, ideally in the range of 440 nm to 485 nm). It is worth noting that R, G, and B layers can produce a certain degree of light outside the indicated range, but the amount is always less than the primary color. Y (yellow) indicates a layer or unit that emits a large amount of both R and G light and a much smaller amount of B light. Unless otherwise specified, wavelengths are expressed as vacuum values ​​rather than in-situ values.

[0053] The OLED light-emitting element of this invention can be a single OLED capable of emitting one monochromatic or multicolor light, a single-stacked OLED, a double-stacked OLED, or even three or more OLED stacks. If monochromatic light output is required or the color temperature of the light output needs to be adjusted or modified, a color filter can be used to eliminate any undesired wavelengths.

[0054] An OLED light-emitting LEL or cell can produce a single "color" of light (i.e., a combination of two primary colors, R, G, and B, such as Y, cyan, or W (white)). Individual OLED light-emitting cells may have a single emitting layer or more emitting layers (directly adjacent to each other or separated by an intermediate layer). Individual light-emitting cells may also contain various non-emitting layers (such as hole transport layers, electron transport layers, blocking layers, and other layers known in this art) to provide desired effects, such as promoting emission and managing charge transfer across the light-emitting cells. Monochromatic light can be produced within an OLED cell by a single layer of one or more emitters of the same color, or by multiple layers, each having the same or different emitters (whose primary emission falls within the same color). The monochromatic light provided by an OLED cell can be a combination of two primary colors; specifically, a yellow-emitting OLED cell that produces a combination of R and G light. In this case, yellow is considered a monochromatic light.

[0055] A stacked OLED device can produce monochromatic light or multi-color light (multi-mode). For example, a multi-mode OLED produces white light with roughly equal amounts of R, G, and B light. Typically, this would correspond to CIE x and CIE y values ​​of about 0.33 and 0.33, respectively. White light, even without equal amounts of R, G, and B light, can generally be produced in an OLED by having three separate R, G, and B emitting layers, two separate emitting layers (such as blue and yellow), or even a single white emitting layer. A red emitting OLED will have CIE x and CIE y values ​​of about 0.6 to 0.7 and 0.2 to 0.35, respectively. The OLED of the present invention can utilize a microcavity effect to increase the emission of a desired color of light.

[0056] For specific applications (such as automotive taillights used for signal braking, stopping, turning, and other functions), the light output of the OLEDs used should be selected to meet all government regulations and SAE or industry standards applicable to that application, particularly in terms of color and brightness. Additionally, the size and dimensions of the segmented OLED devices should be selected to comply with all appropriate government regulations and industry standards applicable to the specific application. For these applications, red is the preferred emission color.

[0057] Segmented OLED devices comprising multiple individual OLED segments on a common substrate can have any shape as needed. "Common" should mean that all OLED segments in the array share the same substrate and are manufactured together as an array on that substrate. It can be completely flat or planar, may have multiple planar surfaces angled relative to each other, may be completely curved, or may have a mixture of flat, angled, or curved surfaces. Typically, the OLED array will have an active (total) emitting region defined by the outer edges of the area containing the individual OLED segments and excluding the non-emitting gaps between segments, surrounded by a non-emitting boundary or edge region. The segmented OLED device will typically be housed within a housing or module portion, along with any necessary external power supply connections and control elements for supplying a signal or power to the individual segments. The housing or module will typically have transparent sections that allow light from the OLED device to pass through while still providing protection from the external environment. The housing or module may also have internal reflectors or light guides to facilitate light conduction as needed. The entire housing or module containing the segmented OLED device can be hermetically sealed. The size of a segmented OLED device suitable for automotive taillight applications typically ranges from 10 cm² to 500 cm².

[0058] In a segmented OLED device, each individual OLED segment should have uniform light emission across the active area of ​​the segment, be undivided, and powered by a single source and signal. A segmented OLED device with individually controlled segments configured as an array can be used for illumination purposes, wherein all segments are activated simultaneously to provide uniform light emission (except for the gaps between segments). Light emission across all segments can be constant, as a dimming, as brightening, and / or flickering / off. Alternatively, a segmented OLED device can have segments that are individually and independently activated according to a certain pattern. The pattern may involve some segments that are fully on, some segments that are at intermediate brightness levels, and some segments that are off. The pattern can be constant or movable over a period of time, wherein individual segments are turned on / off according to a certain type of time-based or position-based sequence. Because a segmented OLED device is not a high-resolution display and is generally meant to be viewed from a considerable distance, an individual OLED segment is substantially larger than an individual pixel in a high-resolution display (which typically has an emission area much smaller than 0.1 mm²). Ideally, for smaller segmented OLED devices with a total emission area of ​​500 cm² or less, each individual OLED segment should have an emission area of ​​at least 1 mm² and ideally at least 3 mm². For larger segmented devices with a total emission area greater than 500 cm², each individual OLED segment should have an emission area of ​​at least 0.25 cm², more ideally at least 1.0 cm², and most ideally at least 10 cm².

[0059] Individual OLED segments can have any shape or area as needed. Generally, to minimize the non-emissive space between individual segments, the segments will form a compact array. Ideally, the array is a regular array, resulting in uniform spacing between segments and providing a smooth appearance. The array can be of any overall shape and does not have to be square or rectangular, but can also be circular, elliptical, triangular, or polygonal. In some designs, some areas of the array are regular in shape with uniform spacing between them, while other parts of the array are irregular. For example, in a square array, the outer part of the array may have smaller square segments set according to a uniform pattern, while the inner region has a single larger star-shaped segment surrounding a large non-emissive area at its precise center. Similarly, the shape of individual OLED segments within the array is not limited and can be square, rectangular, circular, elliptical, triangular, polygonal, or even irregular as needed.

[0060] Furthermore, the OLED segments within the array do not need to be all the same shape, but can have a mixture of shapes, such as (for example) interlocking triangles and hexagons. Compact arrays with only triangles, only parallelograms, or a mixture of triangles and hexagons, or triangles and trapezoids are preferred. Individual segments do not necessarily have the same area, and the array can be composed of a mixture of large and small segments. Individual segments in the array do not need to emit the same color (but each individual segment will emit a single color), and segments emitting different colors can be positioned within the array according to a specific pattern.

[0061] Figures 2A and 2C illustrate the problem of using opaque power feed lines in the light emission path of an exemplary segmented OLED device 100 according to a prior art. Figures 2A and 2B are top views (from the emission side) of 100, which is an array of seven irregular OLED segments S1 to S7 of different sizes and relative positions. However, due to the arrangement of the OLED segments within the array, it is not necessary to run the power feed line to some segments below or above other OLED segments, and there is no electrical contact between the power feed line and the overlying or underlying OLED segments.

[0062] Figure 2C is a cross-sectional view from edge 1 indicated in Figure 2A. Power feed lines P1 to P7 are positioned on top of a transparent substrate 10, and each of the power feed lines P1 to P7 is individually and uniquely electrically connected to segments S1 to S7. Power feed lines P1 to P7 are opaque. An electrically insulating layer 15 is located between and above the power feed lines P1 to P7, which prevents electrical contact between the individual power feed lines and provides planarization of the upper surface. Layer 15 is transparent. Transparent individual OLED bottom electrode segments 20 are positioned on the insulating layer 15. Electrical contact between appropriate dedicated power feed lines and their electrode segments is generated through pathways (openings) V1 to V7 in the insulating layer 15. An insulating layer (pixel defining layer or PDL) 17 is located between the bottom electrode segments 20, so that there is no electrical contact between them. A common organic layer (or layers) 25 for light emission and a common reflective upper or top electrode 30 are located on the bottom electrode segments 20. A bottom electrode segment 20, an emissive layer 25, and a top electrode 30 together form a separate OLED segment, the emitting region of which generally corresponds to the bottom electrode segment. An encapsulation layer 35 is located on top of the OLED segment and outside the OLED array. In the view shown in Figure 2C, only segments S1 and S2 are visible, along with a non-emissive gap 5 based on the insulating layer 17. Although shown here as being between segments S1 and S2, gap 5 can refer to a non-emissive gap between any two adjacent emitting segments. Emission from the LEL 25 passes through the transmissive bottom electrode segment 20, the insulating layer 15, and the transparent substrate 10, as indicated by the arrows. Opaque power feed lines P4 and P5 are directly located in the emission path from S1, and opaque power feed lines P6 and P7 are directly located in the emission path from S2. Power feeders P1 and P2 terminate before any transmission area (see Figure 2A), and power feeder P3 is located below the non-transmission gap 5 according to layer 17 and is therefore not in any segment of the transmission path.

[0063] Figure 2A shows a device 100 in a non-emitting, unlit state. Note that the area of ​​the encapsulation 35 is smaller than that of the substrate 10, therefore the ends of power feed lines P1 to P7 are not covered and are exposed along edge 1. This forms a contact area for the power feed lines, which can then be electrically connected to an external controller / power supply. As illustrated, power feed line P1 is connected to OLED segment S1 only through path V1, P2 is connected to OLED segment S2 only through path V2, and so on. That is, each individual power feed line is electrically connected to a single OLED segment and not electrically connected to other OLED segments. In this example, all power feed lines have the same width that is constant along their length.

[0064] Because the substrate 10, insulating layer 15, bottom electrode segment 20, and LEL 25 are all transparent, ambient light can enter the device, be reflected from the reflective top electrode 30, and return. However, the power feed lines P1 to P7 are opaque and therefore visible to an observer, as indicated by the solid black lines. The power feed line P3, located in the gap 5, may be visible or invisible depending on whether the insulating layer 17 is transparent (in this example, 17 is transparent and therefore P3 is visible). However, because the power feed line P3 is opaque and represents a significant percentage of the gap's area, the overall appearance of the gap may appear darker than that of the OLED segments under these conditions.

[0065] It is readily apparent that the visible pattern of the power feed lines in 100 is non-uniform in a non-operating state; that is, some power feed lines are visible in some OLED segments (i.e., S1, S2, S3, and S6) but not in other OLED segments (i.e., S4, S5, and S7). The power feed lines appear as partial lines only in some portions of the array. Because the human visual system is more likely to distinguish irregular patterns (such as in 100) than regular patterns, the visual appearance of 100 can be interpreted as less smooth, smooth, and glossy.

[0066] Figure 2B shows the device 100 in a single-light emission state. This is illustrated herein by presenting the non-emission areas as dark (because in the single-light state, these areas will be perceived as dark). Because gap 5 is non-emission, it becomes much less noticeable than the emission segments S1 to S7. Therefore, the power feeds P1 to P3 located in the non-emission area (i.e., gap 5) should not be very visible. At a lower emission level, power feed P7 will be considered as a line running across S6, power feeds P4 and P5 will be considered as lines running across S1, P6 and P7 will be considered as lines running across S2, and all four power feeds will be considered as lines crossing S3.

[0067] This is undesirable because the irregular pattern of the lines would be very obvious and noticeable. At higher emission levels, the power feed line, although opaque, may be visible or invisible due to light diffraction and / or viewing distance.

[0068] In the following figures of the OLED array of this invention, the array shown is for illustration only and is intended to demonstrate how the presence of power feed lines (with or without additional extension lines) can be used to generate a visible pattern of uniformly spaced parallel lines in an unlit or lit state. Different array layouts can affect what kind of visible pattern, which can be produced by the presence of opaque or partially opaque lines in the emission path. The visible pattern can differ between the unlit and lit states. The relative importance of the visible pattern in an unlit or lit state will depend on the application. Many options are possible.

[0069] Figures 3A and 3B illustrate a device 200 of the present invention, wherein the opaque power feed line is configured as at least part of a visible pattern of uniformly spaced parallel lines of a constant width that appear to extend continuously across all active regions from one OLED segment to another within the array.

[0070] Figure 3A illustrates the device 200 of the present invention (in an unlit state), which is similar to 100 in Figure 2A, except that it contains a pattern of visible pattern lines 50. This pattern generates a regular visible pattern of uniformly spaced parallel lines that extend linearly across all OLED segments in the array and are all separated by the same distance d. In 200, there are two different types of visible pattern lines 50 contained within the uniformly spaced visible pattern. It should be noted that power feeds P1 and P2 supply power to S1 and S2, which are positioned close to the edges of the device and are therefore invisible and not part of the pattern.

[0071] One type of visible line 50 within the pattern of 200 includes an extension line 50a extending beyond an associated power feeder. In prior art example 100, power feeders P3 to P7 do not extend through passages V3 to V7, resulting in an incomplete appearance of the visible lines they produce. An extension line 50a, having the same width and visible appearance as P3 to P7, is added as a linear extension to the power feeders (appearing as a segment of a line). The purpose of the extension line 50a is to create the visual impression of a complete and continuous straight line extending across the segment without bending, kinking, or curvature, as part of a uniform pattern of visible lines 50. In some examples, an extension line 50a may be associated with a power line within a gap (e.g., see the extension line 50a associated with P3 located within gap 5).

[0072] At least some visible lines 50 of the pattern will have two distinct segments (power feed line and extension line) and will appear to be continuous, but they are discontinuous because the space or gap between the power feed line and the extension line is too small to be easily seen. The extension line 50a is electrically isolated from any of the power feed lines and any of the bottom electrode segments of the OLED and does not directly control, participate in, or supply power for the operation of the OLED segments. The space or gap between the electrically isolated power feed line and the extension line is filled with an electrically insulating layer 15. This is illustrated in an enlarged view of Figure 3A, showing the area around S4 connected to P4 via the passage V4. P4 terminates at the electrical connection leading to the edge of S4. The extension line 50a, which continues the line across S4, is not connected to P4 at all. However, the space or gap between the extension line 50a and P4 is large enough to prevent an electrical connection but not large enough to be visible, making 50a appear as a linear continuation of P4 across S4. Ideally, extension line 50a will appear identical to the power feed and therefore will be made of the same material, appear to have the same width and height, and be positioned within the emission path. Extension line 50a is also expected to be laterally positioned in a plane above the substrate identical to the power feed.

[0073] Another type of visible line within the pattern in 200 includes an additional pattern line 50b, which is neither associated with any power feed nor a linear continuation of any power feed. If the power feeds are too far apart due to different segment sizes, this additional pattern line 50b may be needed to maintain a constant distance d between the visible lines of the pattern.

[0074] Any number of additional pattern lines 50b may exist. The visibility of the additional pattern lines 50b should appear identical to the other lines of the pattern. Desiredly, they should appear to have the same width and height, composition, and position as the extension lines 50a. Like the extension lines 50a, the additional pattern lines 50b are electrically isolated from any power feed lines and any of the bottom electrode segments of the OLED and do not directly control, participate in, or supply power for the operation of the OLED segments. The spaces or gaps between the electrically isolated additional pattern lines 50b are filled with an electrically insulating layer 15. For example, in 200, there is one additional pattern line 50b across S1 and S3 between P4 and P5 and two additional pattern lines 50b between P2 and P6, but they are not associated with any power feed lines.

[0075] Furthermore, an additional pattern line 50b may be required, the portion of which can be positioned within a gap 5 and may not extend completely across the array. For example, referring to the additional pattern line 50b leading to the right side of P4 in Figure 3A, it may be partially positioned within the gap 5 between S4 and S5 to maintain a uniform pattern. In such cases, and under certain viewing conditions (e.g., when the array is emitting as shown in Figure 3B), the gap 5 may be a portion of the visible pattern.

[0076] Figure 3A (as in Figure 2A) shows 200 in a non-emitting, unlit state, where it is assumed that gap 5 (according to layer 17) is transparent. The opaque power feed lines P3 to P7, together with their associated extension lines 50a or additional pattern lines 50b, form one of the visible (attributed to reflection of ambient light) uniform patterns of uniformly spaced parallel lines 50 extending across all OLED segments within the array. The visible pattern of the uniformly spaced parallel lines 50 consists of the power feed lines and their associated extension lines 50a, the additional pattern lines 50b, and (partially) the gap 5.

[0077] Figure 3B (similar to Figure 2B) shows 200 in a single-light, emitting state, where gap 5, being non-emitting, becomes far less noticeable than emitting segments S1 to S7, effectively revealing both dark and visible patterns. At lower emission levels, power feeds P4, P5, P6, and P7, along with extension lines 50a and additional pattern lines 50b, will be visible across all OLED segments in the array according to a regularly spaced pattern. In this example, the non-emitting gap 5 can appear as a portion of the pattern of the power feeds and extension lines 50a. For example, the gap between S4 and S5 can appear as a linear continuation of line 50b across S1 and S3. Similarly, the gap between segments S1 and S2 (where power feed P3 is located) can also appear as a portion of the same line 50a across S3 and S5. In these cases, gap 5 should be designed to be approximately the same width as or as close as possible to the extension lines.

[0078] Figure 3C is a cross-sectional view along line xy 200 as indicated in Figure 3A. It is similar to the view 100 shown in Figure 2C, with the addition of additional pattern lines 50b above the transparent substrate 10 and below the bottom electrode segments 20 of S1 and S2. The relative spacing between the power feed lines P3 to P6 and the additional pattern lines 50b is adjusted to a constant distance d. In this example, the edge of the emission region of the OLED array is maintained at the same distance d from the nearest visible lines (which are power feed lines P4 and P7). Although this is desirable, it is not always necessary, and the distance between the pattern of the visible lines 50 and the edge of the OLED array is not limited to the same spacing d used between the visible lines.

[0079] Figure 3D is a cross-sectional view along line x'-y' 200 as indicated in Figure 3A. In this view, the extension line 50a (associated with P3) can be seen running under S3 but not touching S3.

[0080] Because a uniform, regular pattern of lines is less noticeable than an irregular, non-uniform pattern, the device 200 of the present invention will appear smoother, more even, and more polished, at least at a lower emission level in both an unlit state and an emitting state.

[0081] To further reduce the perceptibility of a visible pattern formed by a combination of power feed lines, extension lines, and possibly additional patterned lines (and, under some conditions, gaps), it is desirable to make the portion of the pattern located under the bottom electrode segment of the OLED equally divided over the light output of the OLED segment's emission area. For example, a single visible line will appear to divide the OLED segment into two equal parts, two visible lines will appear to divide the OLED segment into three equal parts, and so on. It is worth noting that the presence of the visible lines (located within the emission path) does not directly contact the OLED segment; the effect is that the opaque line portion blocks light emitted from an undivided OLED segment.

[0082] Figure 4A illustrates an embodiment of this type of segmented OLED array 300 under unlit conditions. 300 has three columns of OLED segments, with the second column laterally offset from the first and third columns. All power feeds of the first column (indicated by a solid line) are segmented and positioned from the edge of the substrate to the bottom. All power feeds of the second column pass between the OLED segments in the first column. The power feeds of the third column are positioned such that they equally bisect the light emission from the overlying OLED segments in the first column (i.e., equidistant from any opposite edge) and continue through the gaps between the segments in the second column. The lines generated by these power feeds are then continued by adding an extension line 50a (indicated by a dashed line). To complete the line pattern, an electrically isolated extension line 50a is added to bisect the emission from the OLED segments in the third column. In this way, a pattern of equally spaced lines across the entire array is created, where the lines bisect the OLED segments. Depending on the transparency of the gaps between OLED segments, all such lines can be seen in a non-emitting state. However, they will be less noticeable or perceptible because the uniformly spaced line pattern is regular and the OLED segments are equally divided.

[0083] Figure 4B illustrates a state of emission 300, where only the lines in the emission paths of the OLED segments are readily visible. In this embodiment, where the gaps between the OLED segments are relatively large, the visible pattern of the line 50 (formed by the power feed line and extension line 50a, as shown in Figure 4A) will appear differently than in the same device under an unlit condition. The visible pattern will still equally divide the emission area of ​​the OLED segments and will still be regularly spaced, but will present an offset pattern. It should be noted that in this example, the visible pattern of the line does not extend continuously across all segments within the array. Alternatively, the width of the gaps can be adjusted so that they will be visible as part of the overall pattern of regularly spaced lines. In any case, because all segments are evenly divided by opaque lines according to a regular, uniformly spaced pattern, the appearance will be smoother and more polished than an irregular pattern.

[0084] However, positioning the power feed lines to uniformly divide the emissions from the overlying OLED segments into equal portions may not always be feasible, depending on the layout, shape, and size of the individual OLED segments in the array. Figures 5A to 5B and 6A to 6B illustrate the problem and some possible solutions.

[0085] Figure 5A shows an OLED array 400 in an unlit state. It is similar to 300 in Figure 4A, except that the second column is not offset from the first and third columns, ensuring all OLED segments are vertically aligned. In this case, the power feed line of the third column cannot divide the segments in the second column because the power feed line of the second column will then need to overlap under the OLED segments in the first column. To prevent electrical contact between the power feed lines, they need to be laterally offset from each other. Therefore, the power feed lines (solid lines) of the second and third columns under the segments of the first column will divide the emission of the segments in the first column into three equal parts. To extend the visible pattern of the power feed lines, an extension line 50a (dashed line) under the segments in the second column and two extension lines 50a running under the segments in the third column are then required. In Figure 5A, it should be noted that the pattern of visible line 50 consists of a power feed line and its extension line 50a, which are set as one of two visible lines evenly spaced across the entire vertical line of the segment, and the two lines are evenly spaced apart.

[0086] Figure 5A also shows the selected additional pattern lines 50b (dashed lines) in the gaps between the rows of segments. These visible lines are due to the combination of the two power feed / extension lines described above, rather than being part of the first pattern, but forming a second pattern independent of the first pattern. In this embodiment, the two patterns overlap each other over the entire emission area of ​​the array. Each of the two patterns consists of evenly spaced parallel lines, but the spacing between them is different. Adding this second pattern helps maintain an overall smooth and clean appearance when the gaps between the segments are wide.

[0087] Figure 5B shows an OLED 400 in an emission state. Due to the opaque power feed line located within the emission path, each OLED segment appears to be divided into three equal parts. The additional pattern line 50b positioned in the gaps is not easily visible, and the second pattern disappears, leaving only the first pattern.

[0088] Figures 6A (unlit) and 6B (lit) show an OLED array 500. It is similar to 400 in Figure 5A, except for the pattern of the power feed lines and extension lines 50a. In 500, the power feed lines of the third column are positioned in the gaps between the rows of OLED segments in the first and second columns. This allows the power feed lines (solid lines) / extension lines (dashed lines) in the first and second columns to be positioned the same as in 300. However, the relative positions of the gaps and segments require the power feed lines of the third column to bend within the gaps to contact the OLED segments, as shown in the enlarged view (the path is not shown for clarity). The enlarged view also shows extension lines 50a, which visibly extend the linear pattern of the power feed lines in the third column but do not contact the power feed lines. Figure 6B shows a 500 in a transmit state, which appears to be the same as the 300 in Figure 4B, where the segments appear to be divided by the power feed line 50, but is different from the 400 in Figure 5B, where the segments are divided into three parts.

[0089] It should be noted that allowing a certain degree of nonlinear deviation in the power feed line within the gap can still permit a linear pattern, particularly in a firing state. In many embodiments, such as 500, it is generally desirable to position the power feed line within the gap, even if some sections of the power feed line are nonlinear. For example, Figure 7 illustrates a partial view of a segment of an OLED array, where a power feed line is desired to be positioned within the gaps between different OLED segments and has multiple kinks or bends. The linear pattern can still maintain an appropriate extension line.

[0090] Figures 8A and 8B are for one of OLED arrays 600 consisting of 10 OLED segments (S1 to S10 with their individual power feed lines P1 to P10) with irregular shapes and positions. This example illustrates some trade-offs between the features that may be required to maintain the pattern of visible lines.

[0091] In Figure 8A (unlit), the power feed lines (solid lines) of S2 to S7 in the OLED array 600 are positioned within the gaps but operate under segment S1. In this embodiment, there are two power feed lines within each gap, and as shown in Figure 6A 500, they must have a small non-linear extension to contact the OLED segment through a path (not shown). Two extension lines 50a are used to complete the pattern within the gaps and under S10 but, as shown in the exploded view, do not contact the power feed lines. It should be understood that because the width of the power feed lines is relatively narrow, a single extension line (whose width can be adjusted as needed) can be used to extend the visible lines generated by two or more parallel power feed lines. In this embodiment, the visible pattern of line 50 consists of parallel double lines (which are equally close together), wherein the groups of double lines are evenly spaced by a constant distance d.

[0092] Figure 8B illustrates a 600-degree transmission state, where the power feed line within the gap is not readily visible. A linear pattern of visible lines 50 operates under S1 and S10 but is not apparent in any segment located between them. However, the visible lines under S1 and S10 coincide with the gaps in the portions that will appear as patterns. This is desirable because it maximizes transmission from segments S2 to S9, since there are no visible lines intersecting below them in the transmission path.

[0093] OLED array 600 also depicts a visible pattern of uniformly spaced parallel lines of constant width that appear to extend continuously from one OLED segment to another across all active regions of the array, without needing to be physically continuous across all intermediate segments. Segments of the visible lines can be omitted, as long as the appearance of the existing segments remains aligned with each other, as if they fall along the same lines (e.g., 600). In some embodiments, the gaps between segments can be used as a substitute for one of the omitted segments of the pattern. This is because the human visual system can "fill in" omitted segments and create the impression of a complete line system.

[0094] The OLED array 600 is also illustrated: In some embodiments, power feed lines may be positioned along the outer edge of the OLED array. For example, the power feed lines of S8 to S10 are positioned between the outer edge of the OLED array and the edge of the substrate. Power feed lines along the outer edge but within the encapsulation may not be part of the pattern, as this area is generally not visible even when not illuminated. This edge area is generally covered by the array being mounted or held in place, or may be covered by opaque tape, etc.

[0095] Figures 9A (an unlit view) and 9B (a partially lit view) illustrate an OLED array 700. There are eight OLED segments S1 to S8, each with its own power supply lines P1 to P8. This embodiment illustrates two overlapping patterns that may exist, arranged as parallel, uniformly spaced lines at different angles to each other.

[0096] In 700, portions of power feed lines P5, P7, P3, and P8 are positioned along the edge of the device. Therefore, these portions of the power feed lines are not visible and thus not part of the visible pattern. Other portions of P5, P7, P3, and P8 are positioned in the gaps between OLED segments at an angle to the other gaps in the array (due to the shape of the OLED segments). These power feed lines are extended using extension lines 56. There is also an additional pattern line 54 that is not associated with any power feed line. However, power feed lines P2, P4, and P6 operate under OLED segment S1. Extension lines 58 extend these lines from S2 to S8. As shown in the enlarged view, the additional pattern line 54 is separated from the power feed line (P2 in this view) by a gap, therefore there is no electrical contact between them.

[0097] In 700, there exists a first visible pattern consisting of three evenly spaced parallel lines 50 formed by S5 / 56 and S3 / 56, and an additional pattern line 54 between S1 and S2 / S4 / S6. There also exists a second visible pattern consisting of three evenly spaced parallel lines 51 formed by P2 / 58, S4 / 58, and S6 / 58. The first and second visible patterns are set at an angle to each other, but the power feeds in each pattern remain electrically isolated from each other and from the power feeds in the other pattern. In this case, because the extension lines 56 and 58 do not make electrical contact with any power feed in any pattern, there is no need for a gap at any intersection or crossing point between them.

[0098] In the illuminated view at 700° (Figure 9B), only the first pattern 50 will be visible under certain conditions, because the second pattern 51 is entirely located within the non-emission gap and is not easily visible. It should be noted that due to the irregular layout of the array, OLED segments S2 to S6 will be bisected by visible lines, but OLED segments S1 and S8 will be irregularly divided. However, because the pattern of parallel visible lines extends straight across all registration segments, it will still be considered uniform and regular and therefore less noticeable.

[0099] Figures 10A (unlit) and 10B (lit) illustrate an OLED array 800 having one of nine OLED segments S1 to S9, each containing a corresponding power feed line P1 to P9. In 800, the boundary region surrounding the OLED array is expected to be very small, with insufficient space for any power feed lines. Except for the edges with contact pads, the remaining power feed lines must operate beneath the array.

[0100] To form a regular pattern of lines, all power feeds within the array should have the same width. However, in the 800, OLED segment S9 is very large and will require more power than any other OLED segment. To supply sufficient power to S9, a wider power feed is needed, and therefore all power feeds will need to be wider than required. This will reduce unwanted light emission.

[0101] The diagram 800 illustrates the use of multiple common power feeders to supply sufficient power to a large segment without increasing the width of the power feeders leading to other smaller segments. In 800, several common power feeders with a narrower width can function as a single individual power feeder. For example, the individual power feeder P9 of S9 has two separate contact pads P9a and P9b that receive the same signal from an external driver. P9a and P9b then each split (outside the array area) into two smaller common power feeders than the power feeders located under S1 and S5 and contact S9 with a total of four contact points. This allows S9 to receive power from four distributed paths, rather than a single path as in other segments of the array. All the lines that make up P9 will still be considered an individual power feeder because all lines are common, carry the same signal, and contact only one electrode segment. However, the disadvantage is that this method will require more visible lines and therefore reduce the amount of transmission.

[0102] To reduce the number of visible lines in the array, the split power feed line P9 is positioned near the edge of the array. This configuration results in two different patterns existing in different parts of the same array.

[0103] The first pattern is located in the central portion of the array (S2 to S4 and S6 to S8), wherein power feed line P6 divides S2 and S6, P7 divides S3 and S7, P8 divides S4 and S8, and an associated extension line 50a extends the power feed line across S9. In the first pattern, visible line 50 can be further divided within the central portion of the display.

[0104] The second pattern is formed along the outer edge of the array, where contact pads P9a and P9b each split into two common power feed lines P9, dividing the emissions from S1 and S5 into three equal parts. Associated extension lines 50a cross S9 to complete the linear pattern of each of the common power feed lines P9 and P9'. The second pattern is then formed by four separate but interconnected visible lines 51 resulting from the common power feed lines P9 and associated extension lines 50a. In the second pattern, the spacing between parallel lines is less than that in the first pattern.

[0105] In the 800 series, an example is where the distance between visible lines in the more important central region of the array increases as the distance between visible lines along the edges of the display decreases accordingly. Ideally, a single visible pattern of uniformly spaced parallel lines would exist across the entire array. However, in many configurations, compromises must be made, and for various reasons, more than one pattern may be required. In this case, it is known that, according to the human visual system, the central region of the visual field is more important than the edges.

[0106] If it is necessary for only a portion of the total emission area of ​​the array to be covered by a pattern and the remaining portion to be unpatterned, or if two (or more) visible patterns are required, then it is desirable for one visual pattern to dominate; that is, for more than 50% of the total emission area of ​​the array to be covered by a primary pattern. In both cases, it is desirable for the dominant primary visual pattern to be positioned at the center of the emission area of ​​the array; that is, for any secondary visual patterns to be positioned along the outer edge of the emission area of ​​the array.

[0107] In these cases, the primary visible pattern may have parallel lines separated by a distance (d), while the secondary visible pattern may have parallel lines separated by a different distance (d'), where d' ≠ d. Preferably, d' is less than d, because the increased space between the visible patterns increases the light emission in the central region.

[0108] Figures 11A to 11D illustrate an OLED array 900. There are 18 triangular OLED segments S1 to S18, each with its own power supply line P1 to P18. 900 has two overlapping patterns with parallel uniformly spaced lines set at different angles to form one of the visible grids as in 700 (see Figure 8A), but the overlapping patterns are generated using a different layout.

[0109] In Figure 11A (unlit), the vertical power feed lines P1, P3, P5, P7, P9, P11, P13, P15, and P17 (solid lines) and their associated extension lines 62a (dashed lines) are all positioned perpendicularly to edge 1 and contact the corresponding OLED segments S1, S3, S5, S7, S9, S11, S13, S15, and S17 through pathways (black dots). Vertical additional pattern lines 62b exist in the gaps between segments in the same direction to maintain the spacing between visible lines. These power feed lines / extension lines 62a and additional pattern lines 62b together form a first pattern (in a vertical direction) of uniformly spaced parallel lines 51. The contact pads of these power feed lines extend through the encapsulation 35 to the edge 1 of the substrate.

[0110] A second (horizontal) pattern also exists, consisting of visible lines perpendicular to the first (vertical) pattern. Horizontal power feed lines P14, P8, P2, P16, P10, P4, P18, P12, and P6 (solid lines) are all positioned perpendicular to edge 2 and contact the corresponding OLED segments S14, S8, S2, S16, S10, S4, S18, S12, and S6 via pathways (black dots). A visible extension line 60a (dashed line) extending in the direction of the power feed lines creates a second (horizontal) pattern consisting of uniformly spaced parallel lines 50. Additional horizontal pattern lines 60b (positioned within the gaps) also exist to maintain the uniform spacing of the second pattern. Although the contact pads of these power feed lines are shown along edge 2, the contact pads of the power feed lines can also be positioned on edge 1 by extending along the edge of the substrate (parallel to edge 2) and redirection lines. Therefore, there exists a second horizontal pattern consisting of uniformly spaced lines 50, which are power supply feed lines P14, P8, P2, P16, P10, P4, P18, P12 and P6, their associated extension lines 60a and additional pattern lines 60b.

[0111] However, although the visible impression of 900 (unlit or lit) has a uniform grid, the first and second patterns are vertically separated in space and there is no electrical contact between them. The second pattern is set at a right angle to the first pattern to produce a visible impression of a uniformly spaced square grid of parallel lines, since the distance between the visible lines is the same in both patterns. It should be noted that this grid pattern does not contact the bottom electrode covering the OLED segment (except at one path of each power feed) and does not act as an auxiliary electrode.

[0112] Figure 11B (lit) illustrates that the visual appearance is a uniformly spaced grid of visible lines 51 (vertical) and 50 (horizontal) superimposed on the light-emitting array of OLED segments, and the power feed lines / extension lines or additional pattern lines located in the gaps are not visible in these segments.

[0113] Figure 11C is a cross-sectional view at 90° from edge 1. The power feed lines P1, P3, P5, P7, P9, P11, P13, P15, and P17 are visible on the substrate along with two additional pattern lines 62b not associated with any power feed line. When viewed from above (Figures 11A and 11B), these (along with the extension lines 62a associated with the power feed lines) form a first (vertical) visible pattern 51. Also visible are the pathway V1 connecting P1 to the bottom electrode segment 20 (S1), the pathway V7 connecting P7 to the bottom electrode segment 20 (S7), and the pathway V13 connecting P13 to the bottom electrode segment 20 (S13), as these are the OLED segments closest to edge 1. Above the plane forming the power feed line, extension line, and additional pattern lines of the first pattern, and behind V1, V7, and V13, the side of the power feed line P14 (which is part of the second pattern) along with its outer contact pad P14' is visible. P14 extends from edge 2 to below the edge of the bottom electrode 20 of OLED segment S14 (whose edge is only visible behind 20 of S13) and is connected through passage V14. Extension line 60a extends the line of P14 in the same plane to the far edge of the device. Other passages V3, V5, V9, V11, V15, and V17 of the OLED segment further away from edge 1 are also shown. The remainder of the device is the same as shown in Figures 2C and 3C.

[0114] Figure 11D is a cross-sectional view taken at 90° from edge 2. The end / contact pad (P17') of power feed line P17 and extension line 62a are visible on the substrate (see Figure 11C). Power feed line P17 is electrically connected to segment S17 via passage V17. Other power feed lines / additional pattern lines P15, P13, 60b, P11, P9, P7, 60b, P5, P3, and P1 forming the vertical pattern 51 are directly behind P17 (and therefore not visible). Contact pads (positioned on a grid of insulating layer 15) / power feed lines P14, P8, P2, P16, P10, P4, P18, P12, and P6, along with two additional pattern lines 60b not associated with any power feed line, are located above and electrically isolated from the power feed lines / extension lines on the substrate (see Figure 11C). When viewed from above (Figures 11A and 11B), the power feed lines P14, P8, P2, P16, P10, P4, P18, P12, P6, their associated extension lines 60a, and additional pattern lines 60b will form a second (horizontal) visible pattern 50. The pathway is not shown in this view.

[0115] It should be noted that in Figures 11C and 11D, all power feeds and extensions are completely surrounded by the electrical insulating layer 15 (except where the power feeds and extensions of the second pattern contact the substrate 10). In practice, the power feeds and associated extensions / additional pattern lines of the first pattern are patterned on the transparent substrate and completely covered by the insulating layer 15. The power feeds / extensions / additional pattern lines of the second pattern are then patterned on top of the insulating layer. The second pattern is then completely covered by further insulating layers 15. In this way, the first and second patterns of the lines occupy different vertical spaces within the insulating layer, and there is no electrical contact between any power feeds in either pattern or between different patterns. Furthermore, the insulating layer 15 prevents the power feeds from making electrical contact with any of the bottom electrodes 20, except through a path from one of the appropriate individual power feeds. The same composition of the insulating layer 15 may always exist between the top of the transparent substrate and the bottom of the electrode segment 20 / PDL 17, or different electrical insulating materials may be used in two or more layers.

[0116] This invention relies on the human visual system's response to regular patterns of parallel lines. The most important characteristics are the spacing d (distance between lines), frequency (number of lines within a given distance), line width, and line contrast (the difference in opacity between the line and the background). Generally, spatial patterns that are small enough and / or far enough away will be invisible. For example, some computational examples (italic values ​​indicate invisible patterns): Viewing distance -> 0.2m 2m 5m The physiological cycle corresponding to the visual acuity limit of 60 cpd 0.058mm 0.58mm 1.5mm Physiological cycle corresponding to maximum visual sensitivity of 3 cpd 1.2mm 12mm 29mm Frequency of 215 μm periodic pattern 32.5cpd 325cpd 812cpd Frequency of 155 μm periodic pattern 45.1cpd 451cpd 1128cpd

[0117] As a further illustration, the following image has four quadrants. The upper left quadrant has a pattern of thick lines that are evenly spaced but widely separated. The lower left quadrant has thinner lines that are more closely spaced together. The upper right quadrant has even thinner lines that are more closely spaced. The lower right quadrant has the thinnest lines that are very closely spaced. It is evident that the visibility of a pattern becomes less perceptible as the width of the lines and the distance between them (the period of the pattern) decreases. Regardless of the period, as the thickness of the lines in the pattern increases proportionally to the period of the pattern (effectively increasing the coverage area), this will manifest as a decrease in brightness.

[0118] It is evident that the visibility of a pattern becomes less perceptible as the width of the lines and the distance between them decreases. As the lines of a pattern become narrower and closer together, the change will manifest as a difference in brightness.

[0119] The visual acuity limit is approximately 60 cycles per degree (cpd), meaning 60 line pairs per viewing angle, or equivalently, 1 cycle per minute of viewing angle for any periodic pattern. The viewing angle varies depending on both the size of the pattern and the viewing distance. The spatial frequency of cpd can be calculated from the line spacing as follows: f = 2 * tan(0.5) * D / p, where f is the spatial frequency of cpd, D is the viewing distance, and p is the period or line spacing (also referred to as distance d), and the length units of D and p are matched. Peak visual sensitivity is approximately 3 cpd to approximately 5 cpd, and sensitivity decreases rapidly at higher frequencies. Some references regarding the visibility of periodic patterns based on contrast, size, brightness, and other factors include: PGJ Barten's "Formula for the Contrast Sensitivity of the Human Eye in Image Quality and System Performance" (SPIE-IS&T Electronic Imaging, SPIE Proceedings, Vol. 5294 (2004)) and RK Mantiuk et al.'s "A Unified Model of Contrast Sensitivity as the Function of Spatio-Temporal Frequency, Eccentricity, Luminance and Area" (SCO Graphics Journal 41, 4, Article 145 (July 2022)).

[0120] For large arrays, it is anticipated that each OLED segment will require multiple power feed lines / extension lines / additional pattern lines in its emission path. For example, in an array with 224 OLED segments (64 hexagons @ 21 mm², 16 half-hexagons @ 10 mm², and 144 triangles @ 3 mm², for a total area of ​​1936 mm²), 224 individual power feed lines are required, with only a small number positioned within a gap. In this example, the hexagonal segments will be intersected by 26 visible lines, the half-hexagonal segments by 16 lines, and the triangular segments by 12 lines. In a large array (100 or more OLED segments), each OLED segment within a parallel line pattern may have as few as one visible line or as many as 50 visible lines, depending on the size of the individual segments.

[0121] Because of the presence of opaque or light-blocking power feed lines and extension lines or additional pattern lines located in the emission path, the total emission from the OLED array will be impaired due to the large number of lines, which are particularly closely spaced. Desiredly, the presence of power feed lines and extension lines or additional pattern lines will cause a loss of no more than 30% in total emission (compared to the absence of lines), and more preferably, no more than 25% and most preferably, no more than 20%.

[0122] It is desired that all segments within the array or at least a single pattern have a peak luminance of no more than one JND. It should be noted that, generally, one of the relevant luminance ranges for a minimum perceptible difference (JND) is approximately one 1% luminance difference (equivalent to 1% of the difference in (1 - coverage area)). For example, for an 18.5% coverage area, the transmitted intensity is 0.815, such that 1% = 0.008, therefore the intensity (proportional to luminance) difference will be one JND. Preferably, all segments should have a peak luminance of cd / m², preferably + / - 10%, and more preferably + / - 5% if the distance between parallel lines is 2 mm or greater, or preferably + / - 1% if the distance between parallel lines is less than 2 mm, regardless of the percentage loss caused by the presence of opaque lines in the emission path.

[0123] The spacing between parallel visible lines in the pattern depends on the layout and number of OLED segments in the array and the width of the visible lines. At least, the spacing d between parallel lines should be at least 0.05 mm (50 μm) and a maximum value not greater than 10 mm, preferably not greater than 5 mm, and most preferably not greater than 1 mm.

[0124] The width of all visible lines should appear constant within the pattern; that is, the line width does not need to be physically constant, as long as there is no perceptible or obvious variability along the line length or between lines. The width of the power feed line should be 5 μm or greater, and preferably in the range of 0.005 mm to 1 mm. The height of the power feed line should be 0.03 μm or greater, and preferably in the range of 0.1 μm to 2 μm. It should be noted that if the power feed line is opaque and blocks 100% of the light, the height of individual power feed lines can differ from each other with little impact on their visibility. This is useful for minimizing the IR voltage drop on the power feed line. At least, if the gap is part of the pattern, the width of the non-emission gap 5 should be similar to the width of the visible line (or, if grouped together, the width of the group). If it is a part of a non-visible pattern, it should be significantly wider than a visible line by at least 5 times. One of the desired ranges for the width of a non-patterned gap is at least 0.005 mm and 20 mm or less, preferably 2 mm or less, and most preferably 0.25 mm or less. It is desirable that the width of the gap between all OLED segments in the array be as constant as possible.

[0125] There are two well-known phenomena that can affect the visibility or perceptibility of a pattern of uniformly spaced parallel lines. The first is spatial frequency adaptation. Some reviews can be found in: "SEEING THE LIGHT: Optics in Nature, Photography, Color, Vision and Holography," DS Falk et al., John Wiley & Sons, 1986: Chapter 7.8; "Channels, Spatial Frequency and Tilt"; "Emergent Techniques for Assessment of Visual Performance, Committee on Vision," National Research Council, National Academy of Sciences Press, Washington, D.C., 1985; and "Perception Lecture Notes: Spatial Frequency Channels" (Professor Michael Landy), see https: / / www.cns.nyu.edu / ~david / courses / perception / lecturenotes / channels / channels.html. In spatial frequency adaptation, the human visual system perceives a regular pattern as decreasing over time. A regular pattern is required, and the human eye must scan the pattern in all directions to induce adaptation. In spatial frequency adaptation, the distance / frequency between parallel lines is the most important factor and is usually described by a sine wave. A secondary consideration is usually the "sharpness" of the lines; that is, whether the edges of the lines are clearly defined (based on density differences within a distance) or more diffuse.

[0126] The second important phenomenon is the Poggendorff illusion (see https: / / en.wikipedia.org / wiki / Poggendorff_illusion), an optical illusion involving the brain's perception of the interaction between diagonals and horizontal and vertical edges. A typical example is the shift, discontinuity, and / or angular difference that occurs when a thin line is blocked by a thicker line. The Poggendorff illusion depends on the steepness of the interacting lines. As the slope decreases, the illusion becomes less pronounced.

[0127] Figure 12A illustrates the problem caused by the overlap of relatively thick (non-emissive) gaps between the uniformly spaced parallel lines of the pattern and the OLED segments. Depending on the shape of the OLED segments and their arrangement within the array, the sides of the OLED segments may not be perpendicular to the visible lines of the pattern. In Figure 12A, an OLED segment with parallel lines covering approximately 20% of the area exhibits several different gaps at different angles to the lines. The visible lines appear linear across the segments and gaps. If the angle between the segment boundary and the visible line is 90°, the visible line appears to be linearly continuous across the segments. However, at 30°, the visible line appears non-linear at the gap boundaries. The effect is less noticeable at 45° or 60°. Specifically, due to the Poggendorf illusion, the visible line appears to be offset to a certain extent on the opposite side of a segment. This results in an uneven appearance and a jagged effect.

[0128] Figure 12A shows visible lines that are physically aligned across the segment boundaries, but the thin lines that intersect with the thick gaps between the OLED segments at 30º and 45º appear offset and discontinuous. The offset is more pronounced at smaller angles. Figure 12B shows a solution when the Poggendorf illusion is noticeable and annoying. In Figure 12B, the visible lines in the lower segment with the arrows have been slightly shifted to the right, which visually makes the lines appear more continuous across the 60º boundary. Note that although the visible lines in this example are no longer physically aligned as a single continuous line, they appear more continuous. In this example, it should be noted that what matters is the visual appearance of the pattern of evenly spaced parallel lines rather than the actual physical layout of the lines.

[0129] The appearance of a regular line pattern can be affected by the shape of the line's edge contour (corresponding to the line's edge when viewed from above) or its sharpness (vertical height). A square wave intensity (equivalent to brightness) pattern along a straight edge of a line appears sharpest between fully illuminated and fully opaque edge areas, while a line edge with a sinusoidal intensity variation will appear softer and less visible. Intermediates between these extremes can be achieved using translucent, jagged, or irregular edges. It should be noted that these edge contour variations (along the edge or the vertical slope of the edge) will be small compared to the line width and not easily visible at a reasonable viewing distance.

[0130] Contrast ratio (also referred to as amplitude or modulation) has a significant effect on the visibility of a periodic pattern. However, in this case, the power feed lines / extension lines / additional pattern lines of the visible pattern will have a high contrast ratio relative to the background (OLED segments and gaps). If the visible lines are opaque, the contrast ratio is not easily adjustable and is conceptually infinite. It should be noted that the contrast ratio of the visible lines can depend on the effects of ambient light. If the visible lines are composed of metallic and reflective material, they will eventually be brighter than the illuminated area under proper lighting conditions. If they are matte black, they will reflect a small amount of light, slightly reducing the contrast ratio but making the appearance more consistent with changes in lighting. The contrast ratio of the visible lines can also be varied by diffusion. Using an optical diffuser (such as a scattering medium or a textured surface) between the OLED and the viewer will produce lines with both lower amplitude and softer edges. However, this will affect the overall "appearance" of the array when emitting.

[0131] The contrast of a visible line can also be reduced by forming gaps or holes within the body of the line to allow at least some light to pass through. For example, holes can be etched into the body of the line. Alternatively, the visible line can be divided into two or more closely spaced parallel lines separated by a small gap to allow some light to pass through. In this case, the spacing will be small enough that it appears as a single line at a suitable viewing distance. As another alternative, the edges of the line can be made uneven, making it appear blurry or indistinct. In yet another alternative, the edges of the line can be made thinner than the center, making the edges partially transparent. In any case, the thickness of the conductive line can be adjusted to maintain conductivity as needed.

[0132] Ideally, a single, uniformly spaced visual pattern of parallel lines should be superimposed over the entire emission area of ​​a segmented OLED array. However, it is not strictly necessary to make the visible lines less noticeable or perceptible. In many configurations, compromises must be made, and partial or multiple patterns may be necessary for various reasons.

[0133] In practice, some deviations in the overall pattern are acceptable, especially when the amount or magnitude of the deviation is small relative to the total emitting area of ​​the array. It is desirable to superimpose a visible pattern of uniformly spaced parallel lines of constant width onto at least 70% of the total emitting area of ​​the array, and more preferably, at least 80%, and most preferably, at least 90%. The remaining portion of the array's emitting area may not have a visible line pattern.

[0134] In some embodiments, two or more patterns may exist, one of which will be the dominant primary pattern and the others secondary patterns. When there is a primary visible pattern and one or more secondary visible patterns of uniformly spaced parallel lines of constant width, it is desirable that the primary pattern is superimposed on at least 51% of the total emission area of ​​the array. It is desirable that each segment has a consistent visible pattern, with most segments having the primary pattern and a small number of segments having one or more secondary patterns.

[0135] An alternative configuration of a segment combination with different visible patterns is a regular alternation, wherein a segment or group of segments having a primary pattern alternates with a segment or group of segments having a secondary pattern. This can take the form of a striped configuration or a checkerboard configuration of different pattern segments.

[0136] Another alternative configuration of a combination of segments with different visible patterns is a gradient pattern, wherein a group of segments near an edge (e.g., the top) of the array has a primary pattern of visible lines, and an adjacent group of segments has a secondary pattern of visible lines. Further adjacent groups of segments have additional secondary patterns, such that the resulting visual effect is a gradient of one of the following: line pattern period, line thickness, line coverage area, or brightness.

[0137] It is known that, according to the human visual system, the central region of the visual field is more important than the edges. In an example of the 800 series, the distance between visible lines in the more important central region of the array can increase as the distance between visible lines along the edges of the display decreases accordingly. If a primary visual pattern is not superimposed on the entire luminous area of ​​the array, then the desired primary pattern is positioned at the center of the array, and any deviations or secondary patterns are positioned within 20%, preferably 10%, and most preferably 5%, of the total distance from the array to the nearest edge. The desired secondary pattern is limited to segments adjacent to or connected to the edge segments. For example, if the total luminous area of ​​the array is 100 × 200 and the desired distance from the edge is 20%, then the deviations or secondary patterns should be limited to within 20% of the edge along the 100 direction and within 40% of the edge along the 200 direction. Boundaries or spaces may exist between patterns.

[0138] In such cases, the primary or dominant visible pattern may have parallel lines separated by a distance (d), while the secondary visible pattern may have parallel lines separated by a different distance (d'), where d' ≠ d. Preferably, d' is less than d, because the larger space between the visible patterns increases the amount of light emitted in the central region.

[0139] Ideally, a uniformly spaced parallel line of a visible pattern should extend from one edge of the emitting region of the array to the opposite edge, such that the line of the pattern is visible in the emission of all OLED segments along that line. However, the visual pattern may not always extend completely across the entire emitting array, and there may be missing segments within the visual line. For example, see Figures 8A and 8B. In such cases, it is most desirable for the visual line to appear to be registered. That is, the visual line will appear straight, even with large missing segments or solid offsets (compensating for the Poggendorff illusion). This is because the human visual system tends to ignore missing segments of the line when it appears to be registered. In some cases, a missing segment of a visual line may appear to be replaced by a gap between OLED segments; in such cases, the gap should coincide with the visible segment of the line in the pattern.

[0140] It should be noted that visual patterns are not necessarily limited to individual single lines spaced at equal distances. For example, three parallel lines (generated by a power feed / extension / additional pattern line) can be closely spaced together at a small distance. Several such groups of three individual lines can be spaced at a greater distance. When viewed up close, this will form a visual pattern of one group of three lines that are regularly spaced. However, when viewed at a greater distance, the groups of three closely spaced lines will appear to merge into a single, wider line, and therefore the visual pattern will appear to be a single line that is regularly spaced. In both cases, the visual pattern of the lines will appear regular and therefore less obvious or perceptible.

[0141] The transparent substrate 10 can be glass (including flexible glass) or a polymer material. Generally, it will be flat and have a uniform thickness. The top surface of the substrate faces the OLED. Because the substrate will be part of the overall encapsulation of the OLED, it should be sufficiently airtight and watertight to ensure the OLED has the desired lifespan. The substrate can be rigid or flexible. The substrate can have various types of underlayers (i.e., planarization layers, light management layers, etc.), which can be patterned or unpatterned and positioned on the top or bottom surface. Rigid or flexible glass is preferred.

[0142] All or part of the individual power feed lines of each OLED segment can be located within the emission path of another OLED segment (but electrically isolated from it) and will form a visible pattern portion. Within the emission path, the power feed line will be located within an OLED segment between the bottom electrode of an overlying OLED segment and a transparent support (outside the OLED segment) or between the organic light-emitting layer and the bottom electrode. When located within the OLED segment, the power feed line will be electrically isolated from both the organic layer and the underlying bottom electrode.

[0143] Desiredly, power feeds are formed before any organic OLED layer is applied. This is because they must be individually patterned, as each segment contains at least one power feed. One cost-effective way to manufacture power feeds is using photolithography processes and techniques capable of forming very fine patterns of conductive structures. However, photolithography is generally incompatible when used on top of organic OLED layers. Fine metal masking processes and techniques can be used to generate power feeds even on top of organic OLED layers, but they are more expensive and more prone to defects during manufacturing. The conductive structures produced by masking processes are also significantly larger than those produced using photolithography. Regardless of whether the power feed is located above or below the bottom electrode, it is desirable for it to be positioned within an electrically insulating layer.

[0144] In some embodiments, the power feed is positioned between the bottom electrode and the transparent substrate. The power feed is preferably positioned directly on the upper surface of the substrate. Only one power feed should exist per segment. In some examples, the power feed may be split into two or more sub-feeds connected to the same electrode segment at different locations. In some cases, two or more separate but co-operating power feeds (considered equivalent to a single power feed) may be connected to a single segment. For example, one of the drivers with a maximum output of 10 mA is connected to a 20 cm² segment. If the segment requires 1 mA / cm² to produce the desired light output, this segment will require two power feeds (one for each driver or one for each of the two channels of a multi-channel driver). Such configurations can help distribute power more evenly across the segment or reduce IR drop. However, in some examples, the same power feed may be used for two or more segments. Segments that share a common power feed cannot be independently started and are co-emitting are considered equivalent to a single segment.

[0145] An external contact area (also referred to as a contact pad) exists outside the encapsulation, which is electrically connected to each of the power feed lines within the encapsulation. Although the figure shows an extension of one of the power feed lines outside the encapsulation forming the contact area, the encapsulation above the power feed line can also be selectively removed to create electrical contact through the encapsulation. A control power supply is then electrically connected (i.e., by soldering or ACF (anisotropic conductive film)) to these contact areas to supply power to the power feed lines and segment electrodes within the encapsulation as needed. Delivering an appropriate amount of power to the contact area within a suitable time period will cause the OLED segments to emit light at the desired brightness during that time period. The power delivered to the external contact pad is determined by a controller or driver. It is highly desirable that all contact pads be located on the same edge of the substrate.

[0146] The location and distribution of individual power feeds across the substrate surface will depend on the design of the segment array. Some power feeds may be positioned along non-emitting areas (i.e., below gaps and / or at the outer edges of devices), while others may be positioned below or above the bottom electrode of a segment and in the optical path. Depending on the design, some segments may not have any power feeds positioned above or below them, while others may have multiple power feeds. Depending on their location and viewing conditions (i.e., lit or unlit), an individual power feed may be part of a visible or invisible pattern.

[0147] Power feeders, if not completely opaque, are at least partially opaque. Power feeders can be composed of any patternable conductive material. For example, power feeders can be made of: metals such as chromium, aluminum, silver, copper, molybdenum, tungsten, neodymium, titanium, gold, or alloys thereof; conductive metal oxides such as ITO, AZO, IZO, GZO, ZnO, TiN, or SnO2; organic materials such as PEDOT:PSS, CNTs (carbon nanotubes), graphene, or conductive particles such as silver, nickel, or copper suspended in a polymer binder (conductive ink), or any combination of these materials. The conductive material can be in the form of nanowires. Ideally, the power feeder should have a resistivity of less than 25 ohms / square and preferably less than 15 ohms / square.

[0148] Desiredly, the power feeder has two or three layers of at least two conductive materials. The layers may be of equal width or one may be wider than the other. For example, the power feeder may be a two-layer structure having one layer of a conductive metal oxide and another layer made of a metal. ITO is preferred as the conductive metal oxide. In one embodiment, the top layer is a conductive metal oxide and is wider than the bottom metal layer, such that the edges of the bottom layer are covered by the top layer. This helps prevent defects when covered by the insulating layer 15. A suitable three-layer structure may consist of two metal layers and a different metal between them. For example, a Cr / Al / Cr three-layer structure is particularly useful.

[0149] It should be noted that a visible line in a pattern can be composed of two or more power feeds for different segments, wherein the power feeds are electrically isolated from each other. For example, a first power feed can terminate at a path leading to a first segment and form a segment of a visible line, and a second power feed for a second segment can extend linearly along the same visible line generated by the power feed of the first segment, with no electrical contact between the two power feeds. In practice, a power feed for a second OLED segment can act as a linear extension of a power feed for a first OLED segment.

[0150] The visible pattern can be attributed solely to the power feed. However, when the power feed does not extend the full length of the pattern, an extension line is needed to visually extend, fill, or complete the portion of the visible line generated by the power feed. The extension line is separate from the power feed along the same line of the pattern and is not electrically connected to the power feed and is entirely different from an auxiliary electrode. An additional pattern line is similar, except that it is not associated with any extension of the power feed. The purpose of the additional pattern line is to act as a "dummy line" to visually complete the portion of the pattern based on the power feed and the extension line (if present). Therefore, both the extension line and the additional pattern line should appear visually identical to or very similar to the power feed included as part of the visible pattern. The extension line or additional pattern line can be made of any material having an opacity similar to that of the power feed. However, it is most desirable that its appearance and position within the emission path should appear visually identical to or very similar to the power feed. It should be noted that the visual appearance is not always identical or equal in all respects. For example, the visible line generated by two closely spaced power feeds can be extended using a single, wider extension line.

[0151] Although the extension lines and / or additional pattern lines do not directly cause light emission from the OLED segments, they can be used for other purposes within the device. For example, because they can be made of conductive materials, they can serve as general-purpose busbars to help distribute power to a distant portion of the array. As another example, they can serve as part of a passive capacitor structure, in which the bottom electrode of the OLED segment is the upper electrode of the passive capacitor structure, the insulating layer is the dielectric of the passive capacitor structure, and the conductive extension lines and / or additional pattern lines are the lower electrode of the passive capacitor structure.

[0152] Ideally, an insulating layer 15 exists between the transparent substrate 10 and the segmented bottom electrode 20 to surround the power feed and extensions or additional pattern lines, or alternatively, between the upper surface of the bottom electrode and the bottom surface of a power feed. In some embodiments, the insulating layer 15 may be discontinuous and does not need to fill the space between the power feed / bottom electrode / extension / additional pattern line. The upper surface of the insulating layer 15 does not need to be planar, as long as the edge below or above the bottom electrode is not sharp. The insulating layer 15 should prevent short circuits between the power feed / extension or additional pattern line and any bottom electrode segment, and, if necessary, from the organic light-emitting layer. For this reason, the insulating layer should have a resistance of not less than 1 molar (MΩ) and preferably not less than 2 molars. The vertical distance between the top of the power feed / extension or additional pattern line and the bottom electrode segment or organic layer should be greater than 0.1 micrometers to prevent short circuits and not greater than 10 micrometers, and ideally in the range of 1 to 2 micrometers to maintain a thin device. The insulating layer can be organic, including polymers, or inorganic, including mixtures of organic and inorganic materials, or alternating layers of organic and inorganic materials. Suitable organic insulating layers include polyimide, polyacrylate, polyester, epoxy resin, etc., and mixtures thereof. Suitable inorganic insulating layers or materials include SiO2, SiN, SiON, Al2O3, TiO2, etc., or mixtures thereof.

[0153] The insulating layer should be transparent. Ideally, it should have a transmittance of 90% or better. The insulating layer should not scatter light. It should not contain any particles, or if any particles are present, they should be small enough that light is not scattered. The maximum amount of light scattering attributable to the insulating layer should not exceed 10% (measured online when the source light is perpendicular to the substrate and compared with the total light measured in an integrating sphere).

[0154] The electrical connection between the power feed line and the overlying segmented electrode is created through a pathway, which is a hole or path in the insulating material (i.e., insulating layer) separating the two. The pathway extends from the power feed line to the segmented electrode. Ideally, the pathway connects to the segmented electrode at a location corresponding to a non-emitting region of the segmented OLED (such as the edge of the electrode). The pathway can be formed by patterning the insulating material to expose or leave uncovered at least a portion of the surface of the power feed line and / or the bottom electrode. Alternatively, the insulating material can be uniformly deposited and the pathway created by removing material over the desired segment of the power feed line and / or the bottom electrode, thus allowing electrical contact between the two.

[0155] The pathway is filled with a conductive material. When segmented electrodes are deposited on a power feed line, some of the material from the segmented electrodes can fill the pathway to create a connection. Alternatively, the pathway can be filled with a conductive material to contact the segmented electrodes before the power feed line is deposited to create a connection. In some cases, the power feed line needs to be treated with a material that promotes conductivity through the connection before depositing an insulating layer or filling a pathway.

[0156] The length and area of ​​the path are not critical, but it should be sufficient to supply the required power to the segmented electrodes. The path can have any shape along the surface of the power feeder. Specifically, it can extend along one length of the power feeder. There may be more than one path between an individual power feeder and an electrode segment.

[0157] In embodiments where the power feed line is outside the OLED segment, there is an array of individual electrode segments 20 positioned on the power feed line and an insulating layer 15 in which an extension or additional patterned line is embedded. Other interlayers, such as a refractive index reduction layer, may be present. A non-emission lateral gap 5 separating the individual OLED segments exists between all the individual segments on all sides (except those positioned along the outer edge or at the corner of the device).

[0158] A segmented OLED device is a bottom emitter with transparent bottom electrode segments. The transparent electrode segments should transmit as much light as possible, preferably with a transmittance of at least 70%, or more preferably at least 80%. However, in some applications (i.e., microcavity devices), the transparent bottom electrode may be only semi-transparent and have partial reflectivity. Although the bottom transparent electrode can be made of any conductive material, metal oxides such as ITO or AZO, or thin metal layers such as Ag, are preferred. In some cases, an auxiliary electrode may be present to help distribute the charge more uniformly across the transparent electrode area. Ideally, the electrode segments should have a resistivity in the range of less than 25 ohms / square and, preferably, between 10 ohms / square and 23 ohms / square.

[0159] An insulating layer 17 (also referred to as a pixel defining layer (PDL)) is present in gap 5, which separates a portion of one OLED segment from another OLED segment or a portion along the outer periphery of the array. For example, the PDL can separate electrode segments to prevent electrical contact, and can be used to confine the organic layer to the outer edge of a single OLED segment or to define the array. In some cases, it can be used to partially cover electrode segments to prevent light emission in PDL regions (e.g., regions where pathways are positioned along the edges of electrode segments). The PDL can also be used over power lines and extension lines to cover non-planar portions of electrodes or steep steps in electrodes. In other cases where there is no PDL layer in the gap between electrode segments, a PDL positioned along the outer periphery of the array may still be present. The PDL should be insulating (non-conductive).

[0160] In some embodiments, the PDL 17 in the gap 5 between the electrode segments will have a thickness approximately the same as that of the electrode segments. This will create a relatively flat surface for depositing the overlay. In other embodiments, the PDL will be thicker than the electrode segments, and therefore a segment of the PDL will extend beyond the upper surface of the electrode segments in the gap or along the outer edge of the array. In some cases, the extended portion of the PDL will also cover a portion of the upper surface of the electrode surface. In these cases, the PDL can cause undesirable light pipes or light guides. To reduce light pipes, an absorbing dye can be added to the PDL. Alternatively, the PDL layer material can be opaque or black. In this case, any power feeds located under the PDL will be invisible even when the device is not emitting.

[0161] Suitable PDL materials can be polymeric or inorganic and can be the same as or different from the material used for insulating layer 15. Some examples of suitable polymeric PDLs include acrylic and polyimide polymers. Some examples of suitable inorganic PDLs include SiO2, SiN, and SiON.

[0162] In embodiments where the power feed line is located within an OLED segment, there is an array of individual electrode segments 20 / PDL 17 positioned on a transparent substrate, and the power feed line, extension lines, and additional pattern lines (if present) are positioned above the bottom electrode and below the organic light-emitting layer. The power feed line is electrically isolated from the underlying bottom electrode, from each other (along with any extension lines or additional pattern lines), and from the overlying organic layer by an insulating layer 15 in which the power feed line and the extension or additional pattern lines are embedded.

[0163] Figure 13 illustrates a typical composition of one type of OLED layer used for light emission in an OLED device 1000. One or more light-emitting layers and multiple auxiliary layers will be present to facilitate and control the movement of charge between the electrodes during light emission. In this particular example, the bottom electrode segment is an anode and the top electrode is a cathode.

[0164] A transparent bottom electrode segment 20 is positioned on a transparent substrate 10 and an insulating layer 15 having embedded power feed lines and extension lines. A hole injection layer (HIL, layer 1001) may be present on the transparent electrode segment as needed. The purpose of the HIL is to manage the transport of holes from the organic layer to the anode. Suitable hole injection materials are well-known and commonly used. These layers may be mixtures of such materials and may contain dopants that modify their properties. Because they are non-luminescent, they do not contain emitting materials. Generally, only one HIL exists. The selection of appropriate materials is not critical and any can be chosen based on their performance. An example of a suitable HIL material is HAT-CN.

[0165] A hole transport layer (HTL, layer 1002) is positioned above a high-level interlayer (HIL, layer 1001). The purpose of an HTL is to manage hole transport from the HIL to the upper light-emitting layer. Suitable hole transport materials are well-known and commonly used. These layers can be mixtures of such materials and may contain dopants that modify their properties. Because they are non-luminescent, they do not contain emitting materials. Multiple HTLs can exist. The choice of appropriate materials is not critical and any can be chosen based on their performance. An example of a suitable HTL is NPB.

[0166] An exciton blocking layer (EBL; layer 1003) is positioned on top of the HTL (layer 1002) as needed. The light-emitting layer emits light via exciton formation, and in some cases, the excitons have sufficient lifetime to diffuse away from their formation site. The purpose of an EBL is to confine excitons to the LEL to maximize light emission. Suitable exciton blocking materials are well-known and commonly used. These layers can be mixtures of such materials and may contain dopants that modify their properties. Because they are non-luminescent, they do not contain emitting materials. Multiple EBLs can exist. The choice of appropriate materials is not critical and any can be chosen based on their performance. An example of a suitable EBL is mCP.

[0167] A first emitting layer or unit (LEL1; layer 1004) is positioned on top of the EBL (layer 1003). An emitting layer (LEL) (which is a single layer) generally contains one or more non-emitting host compounds and one or more emitting dopants. Suitable host materials and fluorescent, phosphorescent, and TADF emitting dopants for use in the emitting layer or unit are well-known and commonly used. An emitting unit as previously defined can also be used for emission. The selection of appropriate materials is not critical and any can be selected based on their performance and emission characteristics.

[0168] A hole-blocking layer (HBL; layer 1005) is positioned on top of LEL1 (layer 1004) as needed. The light-emitting layer emits light via exciton formation, which in some cases does not form rapidly enough before the hole migrates toward the cathode. The purpose of an HBL is to confine the hole to the LEL to maximize light emission. Suitable hole-blocking materials are well-known and commonly used. These layers can be mixtures of such materials and may contain dopants that modify their properties. Because they are non-luminescent, they do not contain emitting materials. Multiple HBLs can exist. The choice of appropriate materials is not critical and any can be chosen based on their performance. An example of a suitable HBL is SF3-TRZ.

[0169] A charge generation layer (CGL; layer 1006) is positioned above the HBL (layer 1005). The CGL (sometimes also referred to as a connector or interlayer) is positioned between individual OLED light-emitting cells and typically consists of multiple layers. This is because the CGL is structured so that electrons and holes are generated and injected into adjacent organic light-emitting layers upon application of voltage. Therefore, using a single CGL can convert one injected electron into multiple photons, allowing for higher brightness. Specifically, it is desirable for a CGL to be positioned between the light-emitting cells within the stack. However, a light-emitting cell does not need to have an adjacent CGL on both sides. OLED light-emitting cells on the top and bottom of the stack will generally have only one adjacent CGL. Typically, a CGL is not required between a light-emitting cell and one of the top or bottom electrodes, but it may be used as needed.

[0170] Many different types of charge-distributed junctions (CGLs) have been proposed and can be used in OLED stacks. See, for example, US7728517 and US2007 / 0046189. To form a CGL, an np semiconductor heterojunction is typically located at the interface between the n-type and p-type layers for charge generation. Therefore, the CGL will have two or more layers. For example, n-doped organic layer / transparent conductive layer, n-doped organic layer / insulator, n-doped organic material layer / metal oxide layer, and n-doped organic material layer / p-doped organic material layer have all been reported. One of the metal oxides of the CGL is expected to be MoO3. In some examples, the n-layer and p-layer can be separated by a thin intermediate layer. The CGL is typically configured such that the n-layer is closer to the anode and the p-layer is closer to the cathode.

[0171] One desired formulation of a CGL has three layers: an electron transport material doped with an n-doper (e.g., Li), a thin intermediate layer of the same (but undoped) electron transport material, and a hole transport material doped with a p-doper. Another desired formulation of a CGL will have the same type of doped ETL, with an intermediate layer of a different electron transport material and an electron-deficient hole-injecting material (such as HAT-CN). Yet another desired formulation of a CGL will have an undoped ETL layer, a Li or Ca layer, an intermediate layer of the same or a different electron transport material, and an electron-deficient hole-injecting material or a hole transport material doped with a p-doper.

[0172] Materials suitable for electron transport and hole injection or transport, along with suitable n-dopers and p-dopers for use in CGLs, are well-known and commonly used. Materials can be organic or inorganic. The choice of appropriate materials is not critical and can be based on their performance. Ideally, the thickness of the CGL should be in the range of 200 Å to 450 Å, but in some instances, a thinner CGL can be in the range of 100 Å to 200 Å. In many examples, the CGL will have an ETL or HBL on the anode side and an HTL or EBL on the cathode side to facilitate improved charge transport and to facilitate the separation of charge-generating dopants (if present) from the LEL in the light-emitting unit. Multiple such layers can exist and can be doped or undoped as needed.

[0173] The second light-emitting layer or cell (LEL2; layer 1007) of the second stack of the OLED device is positioned on top of CGL (layer 1006). In Figure 13, the two LELs (layers 1004 and 1007) are separated by a CGL (layer 1006), and therefore the OLED stack in Figure 13 is a "double-stacked" (or dual-stacked) OLED. One or more HTLs (doped or undoped) may exist between CGL (layer 1006) and LEL2 (layer 1007). LEL2 may emit the same color as LEL1 or a different color.

[0174] Similar to the description of at least one HBL (layer 1008) of HBL of layer 1005, it is positioned above LEL2 (layer 1007).

[0175] An electron transport layer (ETL; layer 1009) is positioned above the HBL (layer 1008). The purpose of the ETL is to manage the transport of electrons from the EIL to the underlying light-emitting layer. Suitable electron transport materials are well-known and commonly used. These layers can be mixtures of such materials and may contain dopants that modify their properties. Because they are non-luminescent, they do not contain emitting materials. Multiple ETLs can exist. The choice of appropriate materials is not critical and any can be chosen based on their performance. An example of a suitable ETL is TPBI.

[0176] An electron-injected layer (EIL; layer 1010) is positioned above the ETL (layer 1009) as needed. The purpose of the EIL is to manage electron transport from the cathode to the organic layer. Suitable electron-injected materials are well-known and commonly used. These layers can be mixtures of these materials and may contain dopants that modify their properties. Because they are non-luminescent, they do not contain emitting materials. Generally, only one EIL exists. The choice of appropriate materials is not critical and any can be chosen based on their performance. An example of a suitable EIL material is LiF.

[0177] A top electrode 30, which serves as a cathode, is situated atop the organic light-emitting layers (layers 1001 to 1010). Desiredly, it comprises a relatively thick layer of one of the following: a metal or metal alloy (such as Al, Ag, Mg / Al, Mg / Ag, and the like). A second electrode can be deposited using any known technique. The second electrode can be patterned in the non-emitting region, but is generally deposited uniformly over the emitting region. A contact area (contact pad) is required outside the encapsulation, electrically connected to the top electrode within the encapsulation for external power supply. Some examples of suitable materials for the top electrode are Al, Al / Mg, Ag / Mg, and Ag.

[0178] A protective or spacer layer (1011) may be present above the top electrode to prevent damage during encapsulation. This may be a small-molecule organic, polymeric, or inorganic material. Organic materials are preferred.

[0179] Encapsulation 35 is deposited or placed on the reflective cathode and any optional protective layer (if present). At a minimum, the encapsulation should completely cover the top and upper side light-emitting areas and be in direct contact with the substrate. The encapsulation should be airtight and watertight. It can be transparent or opaque. It should not be conductive. It can be formed in situ or added as a separate preform along with the sealing edge.

[0180] One example of in-situ formation is thin-film encapsulation. Thin-film encapsulation involves the deposition of multiple layers having alternating layers of inorganic materials and polymer layers until the desired level of protection is achieved. Formulations and methods for forming thin-film encapsulations are well known and any can be used as needed.

[0181] Alternatively, the encapsulation can be provided as a preformed sheet or a strip cover attached to at least one sealing or enclosing area. The preformed sheet can be rigid or flexible. It can be made of glass (including flexible glass), metal, or organic / inorganic barrier layers. It should have a coefficient of thermal expansion close to that of the substrate to achieve a more robust bond. The preformed encapsulation sheet needs to be attached to the sealing area using air- and water-resistant adhesives (such as silicone or epoxy adhesives) or by thermal methods (such as ultrasonic welding or glass frit welding, which may require additional sealants such as solder or glass frit). The side and bottom edges of the strip cover can be specifically designed to have a better fit to the sealing area or promote a better seal. The strip cover and the sealing area can be designed together so that they partially fit or lock in place before the seal is formed. In addition, the strip cover can be pretreated to promote better adhesion to the sealing area.

[0182] For some applications, an enhanced encapsulation is required. This can be achieved by providing an additional metal foil encapsulation (layer 1013), which is attached to the encapsulation 35 by a pressure-sensitive adhesive (layer 1012). Using a metal foil not only provides a robust encapsulation, but it also acts as a heat sink to prevent excessive heating that is detrimental to the OLED device.

[0183] For many applications, a single stacked OLED device can provide sufficient emission for the desired purpose. For some applications, greater brightness than can be provided by a single OLED stack is required. In these cases, two (as shown in Figure 13) or more stacks will be needed. Generally, adding an OLED stack (i.e., two cells instead of one) will double the brightness produced, but also double the power required. Three stacked OLEDs will produce three times the brightness but require three times the power, and so on. In the segmented OLED device of the present invention, as many stacks as needed to produce the desired amount of brightness can be added; the only limitation is the increased voltage required for the driving device. Desiredly, the segmented OLED device contains at least two stacks and up to six stacks. Formulations and materials suitable for such OLED stacks are well known; for example, US7273663, US9379346, US9741957, US9281487, US2020 / 0013978 and US11031577 all describe OLED stacks having multiple stacks of light-emitting OLED units, each separated by an intermediate interconnect layer or charge-generating layer. Springer et al.'s Optics Express 24 (24), 28131 (2016) reports OLED stacks with 2 and 3 light-emitting units, each unit having a different color. OLED stacks with up to 6 light-emitting units have been reported (Spindler et al., "High Brightness OLED Lighting", SID Display Week 2016, San Francisco, CA, May 23-27, 2016).

[0184] Especially when monochromatic emission is required, another method to increase the brightness from an OLED is to incorporate the microcavity effect. To form a microcavity, one electrode is reflective and the other is translucent, thus light is reflected internally. Depending on the distance between the two electrodes, interference will occur, and some wavelengths of light will be eliminated or reduced, while others will be enhanced. The microcavity effect can be used for OLED segmentation in OLED devices.

[0185] While individual LEDs or cells within a segmented OLED device are not limited to providing the same color, some applications require monochromatic emission. For example, in many automotive taillight applications, all LEDs or cells should produce red light. It should be noted that although all different LEDs or cells can produce the same color light, they do not need to have the same emission spectrum; one may have a different proportion of a particular wavelength than another (i.e., one cell produces a spectrum with more short red wavelengths while another produces more long red wavelengths). For non-monochromatic arrays, the organic layer above the appropriate bottom electrode used for light emission may not be a common layer with other layers. In such cases, the light-emitting layers above each electrode segment are separated by a pixel-defining layer within the gap between the electrode segments. Alternatively, all OLED segments can emit white or multi-mode light, and color filters can be used to produce the desired color of emission from each specific segment.

[0186] A method for manufacturing a bottom-emitting segmented OLED device (such as 200) of an OLED segmented array having a perceptible reduction in the power feed located in the light emission path will sequentially include the following steps: 1) Pattern conductive power feed lines on a transparent substrate such that a dedicated power feed line for each OLED segment, together with any desired extension lines associated with but not in electrical contact with the power feed line, forms a line that appears continuous and forms a visible pattern of uniformly spaced parallel lines of constant width; 2) A non-conductive insulating layer is deposited on the power feed and extension lines (including any lateral space between the power feed and extension lines) and a path is patterned through the insulating layer above the power feed line; 3) Pattern the bottom electrode segments on top of the insulating layer; 4) Deposit the organic layer for light emission onto the electrode segments; 5) Deposit a top electrode onto the organic layer; and 6) Form a capsule on top of the top electrode.

[0187] Another method for manufacturing a bottom-emitting segmented OLED device in an OLED segmented array having a perceptible reduction in the power feed located in the light emission path will sequentially include the following steps: 1) Patterning the bottom electrode for OLED segments on a transparent substrate; 2) Pattern a non-conductive insulating layer over the bottom electrode segments; 3) A pathway is formed in the insulating layer above a bottom electrode segment; 4) Pattern a dedicated power feed line for one of the bottom electrodes (so that it is electrically connected through a path) on the insulating layer, together with any desired extension lines associated with a power feed line but not in electrical contact with the power feed line, such that the power feed line (and associated extension lines (if present)) forms a line that appears continuous and forms a visible pattern of uniformly spaced parallel lines of constant width; 5) Pattern a non-conductive insulating layer on the power feeder and extension lines; 6) Deposit the organic layer for light emission onto the electrode segments and the insulated power feed lines (and associated extensions, if present); 7) Deposit a top electrode onto the organic layer; and 8) Form a capsule on top of the top electrode.

[0188] Some useful variations of these two methods include: the step of patterning a non-conductive insulating layer on the bottom electrode segments; the step of patterning power feed lines and extension lines (if present) including adding additional patterned lines as part of the visible pattern; the step of patterning the bottom electrode segments including forming a non-conductive pixel defining layer between the segments; the step of forming a path for connection between an individual power feed line and a single bottom electrode; and the step of adding a metal heat sink on the encapsulation.

[0189] Some expected performance characteristics of segmented OLED devices with reduced power feed lines include: current density for 2000 cd / m²: 13 mA / cm² (2 stacks), 4.3 mA / cm² (6 stacks); current density for 5000 cd / m²: 32 mA / cm² (2 stacks), 9 mA / cm² (6 stacks); current density for 10000 cd / m²: 25 mA / cm² (6 stacks); and current density for 20000 cd / m²: 50 mA / cm² (6 stacks).

[0190] The above description describes several different embodiments. Individual features from any embodiment can be combined without limitation.

[0191] In the above description, reference is made to the accompanying drawings, which form a part of this document and in which specific embodiments that can be practiced are illustrated. These embodiments have been described in detail to enable those skilled in the art to practice the invention, and it should be understood that other embodiments can be utilized and structural, logical, and electrical changes can be made without departing from the scope of the invention. Therefore, the description of any exemplary embodiments should not be considered as intended to be limiting. Although the invention has been described for illustrative purposes, it should be understood that this detail is for that purpose only and that those skilled in the art can make changes without departing from the spirit and scope of the invention.

[0192] 5: Gap between OLED segments 10: Transparent support components 15: Electrical insulation layer 17: Insulating layer / pixel boundary layer 20: Bottom OLED electrode segmentation 25: Organic light-emitting layer 30: Top OLED electrode 35: Encapsulation 50, 51: A pattern with evenly spaced visible lines 50a, 56, 58, 60a, 62a: Extension lines 50b, 54, 60b, 62b: Additional pattern lines 100 to 900: Segmented OLED Array 1000: OLED device 1001:HIL 1002:HTL 1003:EBL 1004:LEL1 1005:HBL 1006:CGL 1007:LEL2 1008:HBL 1009:ETL 1010:EIL 1011: Select a protective layer 1012: Pressure-sensitive adhesive 1013: Metal foil encapsulation / radiator d: distance / spacing P1, P2, P3…: Individual power supply lines for segmented electrodes P9a, P9b: External contact pads of power feeder P9 S1, S2, S3…: OLED segmentation V1, V2, V3…: Pathways from the power supply feeder to the electrode segments

Claims

1. An OLED device comprising an array of bottom-emitting OLED segments (S1, S2, S3…) disposed on a common transparent substrate (10), each individual OLED segment being separated by a non-emitting gap (5); wherein each OLED segment (S1, S2, S3…) has an active emission region defined by a transparent bottom electrode segment (20), a top electrode (30), and an organic layer (25) for emitting light between the top electrode (30) and the bottom electrode segment (20), wherein the bottom electrode (20) of each segment is electrically connected to an individual power feed (P1, P2, P3…); such that for at least one first OLED segment (S1), there is at least one individual power feed for another OLED segment that is not electrically in contact with the first OLED segment (S1) and is disposed within the emission light path of the first OLED segment (S1); The power feed line of another OLED segment located within the light emission path of the first OLED segment (S1) is included in at least a portion of a visible pattern of parallel lines (50, 51) of constant width and uniform spacing, the visible pattern appearing to extend continuously across the active emission areas of the first (S1) and at least one of the other OLED segments; wherein at least one of the parallel lines of the visible pattern includes: a first line segment which is a separate power feed line (P1, P2, P3...); and a second line segment which is an extension line (50a, 56, 58, 60a, 62a); the extension line is electrically isolated from the power feed line (P1, P2, P3...) in the first line segment and does not directly control, participate in or provide power to the operation of the OLED segments, such that the first and second line segments together form a visiblely continuous straight line.

2. The OLED device of claim 1, wherein the extension lines (50a, 56, 58, 60a, 62a) of the visible pattern are positioned above the substrate in the same plane as the power feed lines (P1, P2, P3...), have the same composition as the power feed lines (P1, P2, P3...), and have the same width as the power feed lines (P1, P2, P3...).

3. The OLED device of claim 2, wherein at least a portion of the visible pattern includes at least one additional pattern line (50b, 54, 60b, 62b) which is separated and electrically isolated from any of the individual power feeds (P1, P2, P3...).

4. The OLED device of claim 3, wherein all individual power feed lines (P1, P2, P3...), extension lines (50a, 56, 58, 60a, 62a) and additional pattern lines (50b, 54, 60b, 62b) within the array are opaque.

5. The OLED device as claimed in claim 4, wherein the individual power feed lines (P1, P2, P3...) comprise layers of chromium and aluminum.

6. An OLED device according to any one of claims 1 to 5, wherein at least two of the uniformly spaced parallel lines (50, 51) of the visible pattern extend from one edge of the light-emitting region of the array to an opposite edge, such that the lines (50, 51) of the pattern are visible in the emission of all OLED segments along the lines.

7. An OLED device according to any one of claims 1 to 5, wherein there are two or more overlapping visible patterns with uniformly spaced parallel lines (50, 51) of constant width, wherein the uniformly spaced parallel lines (50, 51) of each pattern are set to form an angle with each other.

8. An OLED device as claimed in any one of claims 1 to 5, wherein the visible pattern of uniformly spaced parallel lines of constant width is superimposed on at least 70% of the total emitting area of ​​the array.

9. The OLED device of claim 8, wherein there is a primary visible pattern of uniformly spaced parallel lines (50) of constant width and one or more secondary visible patterns of uniformly spaced parallel lines (51) of constant width, wherein the primary visible pattern is superimposed on at least 51% of the total emitting area of ​​the array.

10. The OLED device of claim 9, wherein the primary visible pattern is positioned at the center of the array and all the secondary visible patterns are positioned within 20% of the total distance from the light-emitting area of ​​the array to the nearest edge.

11. An OLED device as claimed in any of claims 1 to 5, wherein a power supply line (P1, P2, P3...) is provided for positioning at least one OLED segment (S1, S2, S3...) within the non-emission gap (5).

12. The OLED device of claim 11, wherein at least one of the parallel lines (50, 51) of the visible pattern is positioned within the non-emission gap (5), the line within the non-emission gap (5) comprising: a first segment which is a separate power feed line (P1, P2, P3...); and a second segment which is an extension line (50a, 56, 58, 60a, 62a); wherein the extension line corresponding to the second segment is electrically isolated from the power feed line in the first segment, such that the first and second segments together form a visiblely continuous straight line.

13. An OLED device as claimed in any of claims 1 to 5, wherein the parallel lines are spaced apart by a distance (d) ranging from 0.05 mm to 10 mm.

14. An OLED device as claimed in any of claims 1 to 5, wherein the width of the parallel lines is in the range of 0.005 mm to 1 mm.

15. The OLED device of claim 1, wherein for a segmented OLED device having a total emitting area of ​​500 cm2 or less, the individual OLED segments shall have an emitting area of ​​at least 1 mm2, and for a segmented device having a total emitting area of ​​more than 500 cm2, the individual OLED segments shall have an emitting area of ​​at least 0.25 cm2.

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