Abstract:
An organic light emitting display includes a first substrate comprising a major surface, and a pixel array formed over the major surface of the first substrate. The pixel array comprises a plurality of pixels formed over the first substrate and a plurality of spacers arranged over the first substrate. Each pixel comprises a first electrode and an organic emission layer formed over the first electrode. The pixel array provides a plurality of recesses and a plurality of bumps, and the plurality of recesses correspond to the first electrodes of the plurality of pixels and the plurality of bumps corresponds to the plurality of spacers. When viewing the pixel array from the top in a first direction perpendicular to the major surface, each spacer is interposed between two immediately neighboring recesses and a row of spacers are arranged along a first axis, and each recess has a first width taken along the first axis and a second width taken along a second axis parallel to the first axis, the first width being smaller than the second width.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims priority to and the benefit of Korean Patent Application No. 10-2013-0121657, filed on Oct. 14, 2013, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference in their entirety. 
       BACKGROUND 
       [0002]    1. Field 
         [0003]    The present disclosure relates to an organic light emitting display. 
         [0004]    2. Description of the Related Art 
         [0005]    With the development of display technologies, display devices have come into wide use in not only household display devices such as TVs and monitors but also portable devices such as notebook computers, cellular phones and portable media players (PMPs). As the display devices become lighter in weight and thinner in thickness, a liquid crystal display, an organic light emitting display and the like have come into the spotlight. 
         [0006]    Among these display devices, the organic light emitting display is self-luminescent using an organic material, and has low power consumption and high luminance characteristics. The organic light emitting display is a next-generation display having the self-luminescent characteristic, and has superior characteristics to a liquid crystal display (LCD) in terms of viewing angle, contrast, response speed, and the like. 
         [0007]    Accordingly, demands for organic light emitting displays have increased, and various studies have been conducted to develop an organic light emitting display having lower power consumption and higher luminance characteristics while increasing the lifespan thereof. 
       SUMMARY 
       [0008]    Embodiments provide an organic light emitting display having a spacer which can minimize the contact area between the spacer and an encapsulation substrate. 
         [0009]    Embodiments also provide an organic light emitting display which can prevent a stain transferred to an encapsulation substrate by an external force from being overlapped with an emission layer. 
         [0010]    Embodiments also provide an organic light emitting display which can improve emission efficiency by providing shapes of a new opening (e.g., light emitting area) and a new spacer, and ensure the uniformity of luminance (e.g., based on transmittance). 
         [0011]    According to an aspect of the present invention, there is provided an organic light emitting display, including: a first substrate comprising a major surface; and a pixel array formed over the major surface of the first substrate, the pixel array comprising a plurality of pixels formed over the first substrate and a plurality of spacers arranged over the first substrate, and each pixel comprising a first electrode and an organic emission layer formed over the first electrode, the pixel array providing a plurality of recesses and a plurality of bumps, the plurality of recesses corresponding to the first electrodes of the plurality of pixels and the plurality of bumps corresponding to the plurality of spacers, wherein when viewing the pixel array from the top in a first direction perpendicular to the major surface, each spacer is interposed between two immediately neighboring recesses and a row of spacers are arranged along a first axis, and each recess has a first width taken along the first axis and a second width taken along a second axis parallel to the first axis, the first width being smaller than the second width. 
         [0012]    Each spacer may comprise a base portion and a top portion placed on the base portion, the base portion being wider than the top portion in a cross section taken by a plane parallel to the first axis and perpendicular to the major surface. 
         [0013]    The tip of the top portion may be rounded. 
         [0014]    The base portion may comprise generally semicircular or trapezoidal sides in a cross section taken by a plane parallel to the first axis and perpendicular to the major surface. 
         [0015]    The pixel array may further include a second electrode formed over the organic emission layer and the plurality of spacers, and a protective layer formed on the second electrode. 
         [0016]    The width of the recess may be the shortest when measured along the first axis and gradually increasing when measured along another axis parallel to the first axis. 
         [0017]    When viewing the pixel array from the top in a first direction perpendicular to the major surface, the recess may have a center line along the first axis, and the center line may be equidistant from each of the two ends of the recess along a third axis that is perpendicular to the first axis and parallel to the major surface. 
         [0018]    When viewing the pixel array from the top in a first direction perpendicular to the major surface, the recess has a center line that divides the recess into first and second portions, the widest width of the first portion measured along the first axis may be substantially equal to the widest width of the second portion measured along the first axis. 
         [0019]    The width of the recess along the center line may be about 20% to about 60% of the widest width of the first or second portion. 
         [0020]    The spacer may be adjacent to a central portion of the recess that is on the first axis. 
         [0021]    When viewing the pixel array from the top in a first direction perpendicular to the major surface, the shape of the spacer may complement the portion of the recess that is on the first axis. 
         [0022]    When viewing the pixel array from the top in a first direction perpendicular to the major surface, the spacer has a shape that is generally circular or rhomboidal. 
         [0023]    The organic light emitting display may further include a thin film transistor coupled to the first electrode. 
         [0024]    The organic light emitting display may further include a second substrate disposed opposite to the first substrate, the second substrate being spaced apart from the first substrate at a predetermined interval by the spacer. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]    Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the example embodiments to those skilled in the art. 
           [0026]    In the drawing figures, dimensions may be exaggerated for clarity of illustration. It will be understood that when an element is referred to as being “between” two elements, it can be the only element between the two elements, or one or more intervening elements may also be present. Like reference numerals refer to like elements throughout. 
           [0027]      FIG. 1A  is a schematic plan view illustrating an organic light emitting display according to an embodiment of the present invention. 
           [0028]      FIG. 1B  is a sectional view of the organic light emitting display shown in  FIG. 1A  according to an embodiment of the present invention. 
           [0029]      FIG. 2  is a top view showing only spacers and recesses in an organic light emitting display according to an embodiment of the present invention. 
           [0030]      FIG. 3  is a sectional view taken along line I-I of  FIG. 2  according to an embodiment of the present invention. 
           [0031]      FIG. 4  is a top view showing only spacers and recesses in an organic light emitting display according to another embodiment of the present invention. 
           [0032]      FIG. 5  is a top view showing only spacers and recesses in an organic light emitting display according to still another embodiment of the present invention. 
           [0033]      FIG. 6  is a sectional view taken along line II-II of  FIG. 5  according to an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0034]    Hereinafter, certain exemplary embodiments according to the present invention will be described with reference to the accompanying drawings. Here, when a first element is described as being coupled to a second element, the first element may be not only directly coupled to the second element but may also be indirectly coupled to the second element via a third element. Further, some of the elements that are not essential to the complete understanding of the invention are omitted for clarity. Also, like reference numerals refer to like elements throughout. 
         [0035]    In the accompanying drawings, an active matrix (AM) organic light emitting display of a 2Tr-1Cap structure having two thin film transistors (TFTs) and one capacitor in one pixel is described, but the present invention are not limited thereto. Therefore, the organic light emitting display may have three or more TFTs and two or more capacitors in one pixel. The organic light emitting display may have various structures as a separate wire is further formed. Here, the pixel refers to a minimum unit that displays an image, and the organic light emitting display displays an image through a plurality of pixels. 
         [0036]      FIG. 1A  is a schematic plan view illustrating an organic light emitting display according to an embodiment of the present invention.  FIG. 1B  is a sectional view of the organic light emitting display shown in  FIG. 1A . 
         [0037]    The organic light emitting display according to this embodiment may include a pixel area  110  and a non-pixel area  120 , which are configured with a plurality of layers on a first substrate  100 . The non-pixel area  120  is provided to surround the pixel area  110 , and may include an area other than the pixel area  110 . 
         [0038]    The pixel area  110  (e.g., pixel array shown in  FIGS. 2 ,  4 , and  5 ) has a plurality of organic light emitting diode devices  220  disposed on the first substrate  100 . Here, the plurality of organic light emitting diode devices  220  are coupled in a matrix form between scan and data lines  130  and  140 . The non-pixel area  120  has scan and data lines  130  and  140 , power supply lines (not shown) and scan and data drivers  150  and  160 , which are disposed on the first substrate  100 . Here, the scan and data lines  130  and  140  are respectively extended from the scan and data lines  130  and  140  in the pixel area  110 . The power supply lines (not shown) are provided to operate the organic light emitting diode devices  220 . The scan and data drivers  150  and  160  process signals provided from outside the organic light emitting display through pads  170  and supply the processed signals to the scan and data lines  130  and  140 . The scan or data driver  150  or  160  includes a driving circuit for selectively driving each organic light emitting diode device  220  by converting a signal provided from the outside through the pad  170  into a scan or data signal. 
         [0039]    Referring to  FIG. 1B , a second substrate  300  (e.g., an encapsulation substrate) may be disposed opposite to the first substrate  100  so as to hermetically seal the pixel area  110  above the first substrate  100  having the organic light emitting diode devices  220  formed thereon, and side surfaces of the first and second substrates  100  and  300  may be bonded together by a sealing material  310 . In this case, the second substrate  300  may be spaced apart from the first substrate  100  at a predetermined interval by a plurality of spacers  230  formed on the first substrate  100 . 
         [0040]      FIG. 2  is a top view showing only the spacers and recesses in an organic light emitting display according to an embodiment of the present invention.  FIG. 3  is a sectional view taken along line I-I of  FIG. 2  according to an embodiment of the present invention. 
         [0041]    Referring to  FIG. 2 , the spacers  230  according to this embodiment may be arranged in the form of dots to be spaced apart from a plurality of recesses  240  arranged in row and column directions. In the present disclosure, the area indicated by  240  (e.g., a portion of the OLED device  220  that is recessed as shown in  FIG. 3 ) is referred to as a recess for convenience. Alternatively, such recess can also be referred to as a recessed area, an opening, a light emitting area, or other labels that describe a similar feature. The organic light emitting diode device  220  may be provided such that at least one portion of the organic light emitting diode device  220  corresponds to the recess  240 . Thus, the organic light emitting diode device  220  may emit light through the recess  240 . In this case, a thin film transistor for controlling an operation of the organic light emitting diode device  220  and a capacitor for maintaining a signal may be coupled to the organic light emitting diode device  220 . However, for convenience of illustration, only a thin film transistor  210  and the organic light emitting diode device  220  are shown in  FIG. 3 . 
         [0042]    The organic light emitting display according to this embodiment includes: a plurality of first electrodes  221  formed on the first substrate  100 ; a pixel defining layer  222  formed on the first substrate  100  over the first electrodes  221 , the pixel defining layer  222  having recesses  240  respectively formed such that the first electrodes  221  in emission areas are exposed therethrough; an organic emission layer  223  formed on the exposed first electrode  221 ; spacers  230  formed on the pixel defining layer  222 ; and a second electrode  224  formed above the first electrodes  221  over the organic emission layers  223  and the spacers  230 . In this case, the spacer  230  is provided at an outside of the recess  240 , and the width S1 (shown in  FIG. 5 ) of a portion adjacent to the spacer  230  in the recess  240  may be smaller than the widths S2 or S3 of another portion of the recess  240 . The organic light emitting display may further include a protective layer  250  formed on the second electrode  224  (e.g., configured to cover the spacers  230 ). For example, the protective layer  250  may be provided to protect a lower layer, and may be formed of an organic material. The organic material may include one or more of LiF, Liq, Alq3, NPB, TPD, m-MTDATA, and TCTA. 
         [0043]    The organic light emitting diode device  220  may include a first electrode  221 , a second electrode  224 , and an organic emission layer  223  provided between the first and second electrodes  221  and  224 . For example, the first electrode  221  may be an anode electrode, and the second electrode  224  may be a cathode electrode. 
         [0044]    The plurality of first electrodes  221  may be formed on the first substrate  100  such that they are spaced apart from each other. The organic emission layer  223  may be formed to cover the recesses  240  (e.g., areas of the respective first electrodes  221  on which pixel defining layer  222  is not formed, as shown in  FIG. 3 ) which are emission areas defined by the pixel defining layer  222 . The organic emission layer  223  may include a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer. The second electrode  224  may be formed above the first electrodes  221  over the organic emission layers  223 . 
         [0045]    The thin film transistor  210  may be electrically coupled to the first electrode  221 . In the example of  FIG. 3 , the thin film transistor  210  includes a semiconductor layer  204  for providing source and drain regions and a channel region, a gate electrode  202  insulated from the semiconductor layer  204  by a gate insulating layer  203 , and source and drain electrodes  205  coupled to the semiconductor layer  204  in the source and drain regions. A buffer layer  201  may be formed beneath the gate electrode  202 , and a planarization insulating layer  206  may be formed on the source and drain electrodes  205 . 
         [0046]    The plurality of spacers  230  are formed on the pixel defining layer  222 , and may be spaced apart from each other and formed adjacent to the boundaries of the recesses  240 . The spacers  230  may be arranged in the form of a mask (not shown) for selectively depositing an organic material or in the form of dots so as to uniformly and stably maintain the interval between the second and first substrates  300  and  100 . In order to decrease the contact area of the spacer  230  with the second substrate  300 , the spacer  230  may be provided such that the width T1 (shown in  FIG. 3 ) of a lower portion adjacent to the pixel defining layer  222  is greater than the width T2 of an upper portion of the spacer  230 . In addition, the spacer  230  may be provided such that an upper portion of the spacer  230  (e.g., a portion of the spacer  230  that faces the second substrate  300 ) is rounded. In one example, the section of the spacer  230  that is substantially perpendicular to the first substrate  100  may be formed in a semicircular or trapezoidal shape, for example, as shown in  FIG. 6 . 
         [0047]    In the spacer  230 , the width T1 of the lower portion adjacent to the pixel defining layer  222  may be greater than that T2 of the upper portion, such that the spacer  230  can stably support the second substrate  300  when the second substrate  300  is drooped downward. The second electrode  224  and the protective layer  250  may be provided on the spacer  230 . In a case where the second substrate  300  is contacted with the protective layer  250 , by decreasing the contact area between the protective layer  250  and the second substrate  300 , the area of a stain transferred to the second substrate  300  may also be decreased. In this case, the upper portion of the spacer  230  may be rounded, such that the contact area between the protective layer  250  and the second substrate  300  is decreased and the impact applied to the second substrate  300  is thereby reduced. 
         [0048]    As described above, the organic light emitting display according to this embodiment may be provided with the second electrode  224 , the protective layer  250 , and the second substrate  300 , which are sequentially formed on the spacer  230 . For example, the second substrate  300  of the organic light emitting display is an encapsulation substrate, which is provided to protect a device and the like inside the organic light emitting display. 
         [0049]    In order to check a failure caused by an external impact, a ball drop test may be performed on the organic light emitting display. The ball drop test is a test for checking a crack in the second substrate, a droop of the second substrate, or the like by dropping a steel ball (weight of 43.75 g and diameter of 22 mm) on a predetermined point of the second substrate  300  from the above the second substrate  300 . The ball drop test is used to simulate an impact that may frequently occur due to characteristics of the organic light emitting display. In the ball drop test, the second substrate  300  may come in contact with the protective layer  250  by being drooped downward. In this case, the protective layer  250  may be made of, for example, an organic material, and a portion of the protective layer  250  may be transferred onto and stain the second substrate  300 . The stain transferred to the second substrate  300  may block light passing through the second substrate  300 . 
         [0050]    Generally, in a case where the second substrate comes in contact with the protective layer by being drooped downward, the second substrate ends up compressing the protective layer, and therefore, the stain transferred to the second substrate is larger than the shape of an upper portion of the protective layer. Accordingly, the stain formed on the second substrate after the second substrate is returned to the original state covers the recess, i.e., the emission area, and the portion covered by the stain is visualized as a stain due to the generation of a luminance difference caused by a transmittance difference. 
         [0051]    In this embodiment, the organic light emitting display can be provided with the spacer  230  and the recess  240 , which are designed such that even when a stain is transferred to the second substrate  300  due to the contact between the second substrate  300  and the protective layer  250 , the stain does not cover the recess, i.e., the emission area. In the organic light emitting display according to this embodiment, the function of the spacer  230  is maintained, and simultaneously, it is possible to improve emission efficiency by increasing the area of the recess  240 . 
         [0052]    The portion at which the protective layer  250  and the second substrate  300  come in contact with each other may be influenced by the spacer  230  provided beneath the protective layer  250 . Since the size of the recess  240  is related to the emission efficiency, the shape of the upper portion of the spacer  230  can minimize the stain of the protective layer  250  that is transferred to the second substrate  300 , while maximizing the size of the recess  240 . 
         [0053]    The recess  240  according to this embodiment may be formed in a dumbbell or ribbon shape where end portions (e.g., in the longitudinal direction) of the recess  240  are larger than the center portion of the recess  240 . In this case, the spacer  230  may be provided adjacent to the portion having the narrowest width in the recess  240 . For example, the recess  240  may include a central portion  241  provided with the narrowest width  51 , an upper portion  242 , and a lower portion  243  respectively provided such that their widths are gradually increased as they get farther away from the central portion  241 . The distance from the central portion  241  to the end of the upper portion  242  may be substantially identical to that from the central portion  241  to the end of the lower portion  243 , and the width S2 of the widest portion of the upper portion  242  may be substantially equal to the width S3 of the widest portion of the lower portion  243 . The spacer  230  may be provided adjacent to the central portion  241  of the recess  240 . 
         [0054]    That is, the recess  240  may be provided such that the central portion  241  is formed at the center of the recess  240 , and the upper and lower portions  242  and  243  are symmetrically provided on the respective sides of the recess  240 . The spacer  230  may be provided adjacent to the central portion  241  having the narrowest width in the recess  240 . In this case, the shape of the spacer  230  may be configured to complement the shape of the central portion  241  in the recess  240 . For example, the portion of the spacer  230  that faces the central portion  241  may mirror the shape of the central portion  241 . As shown in  FIG. 2 , the portion of the spacer  230  that is closest to the central portion  241  of the recess  240  is shaped such that the tip of the portion closest to the central portion  241  fits into the indentation created by the central portion  241  (e.g., the waist formed at the center of the recess  240 ). The spacer  230  may be spaced apart from the recess  240  and adjacent to the central portion  241  of the recess  240  having the narrowest width. Thus, the stain transferred to the second substrate  300  by the protective layer  250  is not overlapped with the recess  240  (i.e., the emission area), and accordingly, it is possible to prevent uniformity (e.g., such as in luminance) from being negatively affected by such stain. Further, the shape of the spacer  230  may be configured to complement the shape of the central portion  241  of the recess  240 , such that it is possible to prevent the light covering of the recess  240  caused by the stain transferred to the second substrate  300  while improving the emission efficiency. Since the end portion of the spacer  230  that faces the second substrate  300  has a round shape, it is possible to reduce the occurrence of a stain by minimizing the contact area between the protective layer  250  and the second substrate  300 . 
         [0055]    In a case where the spacing distance between the recess  240  and the spacer  230  is increased, the light covering of the recess  240 , caused by the stain transferred to the second substrate  300 , may be prevented. However, since the area of the recess  240  (e.g., emission area) is related to the emission efficiency, the emission efficiency of the organic light emitting display may be lowered by allowing the recess  240  and the spacer  230  to be spaced apart from each other, which may become problematic. Accordingly, it is desirable to effectively prevent the recess  240  and the stain transferred to the second substrate  300  from being overlapped with each other while improving the emission efficiency. 
         [0056]    The width S1 of the central portion  241  of the recess  240  is preferably provided to be about 20% to about 60% of the width S2 of the widest portion of the upper portion  242  or the width S3 of the lower portion  243  (e.g., in a top view showing the recess  240 ). In a case where the width  51  of the central portion  241  is less than 20% of the width S2 of the widest portion of the upper portion  242  or the width S3 of the lower portion  243 , the emission efficiency may be decreased, or stress caused by the current applied to the recess  240  may be increased, thereby reducing the lifespan of the organic light emitting display. If the width  51  of the central portion  241  exceeds 60% of the width S2 of the widest portion of the upper portion  242  or the width S3 of the widest portion of the upper portion  243 , the stain transferred to the second substrate  300  by the spacer  230  (or the protective layer  250 ) may be overlapped with the second or third portion  242  or  243  even when the spacer  230  is provided adjacent to the central portion  241 . Therefore, a luminance difference may be generated due to the partial generation of a transmittance difference. 
         [0057]    The spacers  230  according to this embodiment are arranged in the form of dots outside of the recess  240  provided as the emission area. In this case, an upper portion of the spacer  230  (e.g., the portion of the spacer  230  facing the second substrate  300 ) may have a round shape such that the area of the upper portion is smaller than that of a lower portion of the spacer  230 . Thus, the mask for selectively depositing the organic material on only the recess  240  is uniformly supported at a predetermined interval by the spacers  230 , and hence the organic emission layer can be formed in an exact pattern (e.g., shape). Since the spacer  230  constantly maintains the interval between the first and second substrates  100  and  300  while coming in point contact with the second substrate  300 , the contact area between the spacer  230  and the second substrate  300  is minimized, thereby preventing the external appearance of the organic light emitting display from being negatively affected by a stain. Although it has been described in this embodiment that the spacer  230  is distinguished from the pixel defining layer  222 , the spacer  230  may be provided by patterning a portion of the pixel defining layer  222 , similarly to the patterning of the recess  240  on the pixel defining layer  222 . The spacer  230  may be formed of the same material as the pixel defining layer  222 . 
         [0058]      FIG. 4  is a top view showing only spacers and recesses in an organic light emitting display according to another embodiment of the present invention. 
         [0059]    Referring to  FIG. 4 , the spacer  230   a  according to this embodiment may be provided adjacent to the central portion  241  of the recess  240  having the narrowest width, and the shape of the spacer  230   a  may be configured to complement the shape of the central portion  241 . In this case, the cross-section of the spacer  230   a  that is parallel to the first substrate  100  may have a circular shape as shown in  FIG. 4 . Alternatively, the cross-section of the spacer  230   a  may have a rhomboidal shape (e.g., a rhombus) as shown in  FIG. 2 . 
         [0060]      FIG. 5  is a top view showing only spacers and recesses in an organic light emitting display according to still another embodiment of the present invention.  FIG. 6  is a sectional view taken along line II-II of  FIG. 5  according to an embodiment of the present invention. In the organic light emitting display according to this embodiment, contents except the following contents are similar to those of the embodiments described with reference to  FIGS. 1A to 4 , and therefore, their detailed descriptions will be omitted. 
         [0061]    Referring to  FIGS. 5 and 6 , the pixel defining layer  222  in which the recess  240  is formed such that a portion of the first electrode  221  is not covered by the pixel defining layer  222  may be provided on the first substrate  100 , and the organic emission layer  223  may be provided to cover the recess  240 . A spacer  233  is provided outside the recess  240  (e.g., on the pixel defining layer  222 ), to support the second substrate  300  (e.g., an encapsulation substrate) opposite to the first substrate  100 . 
         [0062]    The spacer  233  according to this embodiment may include a support portion  231  adjacent to the pixel defining layer  222 , and a contact portion  232  protruded toward the second substrate  300  from the support portion  231 . The support portion  231  and the contact portion  232  may be provided to have different thicknesses from each other. The support portion  231  and the contact portion  232  may be formed in different shapes from each other. For example, the support portion  231  may be formed by patterning the pixel defining layer  222 . The support portion  231  may be formed in a separate layer. That is, the support portion  231  and the contact portion  232  may not be formed in consecutive shapes but formed in separate shapes, such that it is possible to flexibly change the process of forming the spacer  233 . Further, the support portion  231  may be formed in a shape that is wider than that of the contact portion  232 , such that the spacer  233  can stably support the second substrate  300 . In addition, the contact portion  232  may be formed thinner than the support portion  231 , such that it is possible to prevent a stain formed on the second substrate  300 . 
         [0063]    As described above with respect to the various embodiments of the present invention, it is possible to provide an organic light emitting display having a spacer that can minimize the contact area between the spacer and an encapsulation substrate. 
         [0064]    Further, it is possible to provide an organic light emitting display which can prevent a stain transferred to an encapsulation substrate by an external force from overlapping with an emission layer. 
         [0065]    Further, it is possible to provide an organic light emitting display that can improve emission efficiency by providing shapes of a new opening and a new spacer, and ensure the uniformity of luminance (e.g. based on transmittance). 
         [0066]    Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not in a limiting manner. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present disclosure as set forth in the following claims.