DISPLAY DEVICE
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`CROSS-REFERENCE TO RELATED APPLICATION
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`[0001] This application claims priority from and the benefit of Korean Patent Application
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`No. 10-2017-0069269, filed on June 2, 2017, which is hereby incorporated by reference for all
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`purposes as if fully set forth herein.
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`BACKGROUND
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`[0002] FIELD
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`[0003] Exemplary embodiments relate to a display device.
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`[0004] DISCUSSION OF THE BACKGROUND
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`[0005] Display devices have become increasingly important in accordance with
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`developments in multimedia technology. Accordingly, various types of display devices, such as
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`a liquid crystal display (LCD), an organic light-emitting display, and the like have been used.
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`[0006] An organic light emitting display device, among other display devices, displays
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`an image by using organic light-emitting elements that generate light by recombining electrons
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`and holes. The organic light emitting display device has numerous advantages, such as a high
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`response speed, high luminance, a wide viewing angle, and low power consumption.
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`[0007] The above information disclosed in this Background section is only for
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`enhancement of understanding of the background of the inventive concept, and, therefore, it may
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`contain information that does not form the prior art that is already known in this country to a
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`person of ordinary skill in the art.
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`SUMMARY
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`[0008] Exemplary embodiments provide a display device capable of increasing an
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`effective light-emitting area ratio.
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`[0009] Exemplary embodiments provide also provide a display device capable of
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`minimizing blurring of the displayed image.
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`[0010] However, exemplary embodiments are not restricted to those set forth herein. The
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`above and other exemplary embodiments of the inventive concept will become more apparent to
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`one of ordinary skill in the art to which the inventive concept pertains by referencing the detailed
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`description of the inventive concept given below.
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`[0011] Additional aspects will be set forth in the detailed description which follows, and;
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`in part; will be apparent from the disclosure, or may be learned by practice of the inventive
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`concept.
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`[0012] An exemplary embodiment discloses a display device including a substrate; a first
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`light-emitting element disposed on the substrate; an encapsulation layer disposed on the first
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`light-emitting element; an input sensing layer disposed on the encapsulation layer; and a
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`diffraction pattern layer disposed on the input sensing layer. The diffraction pattern layer may
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`include a plurality of diffraction patterns arranged to have a first period in one direction.
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`[0013] An exemplary embodiment also discloses a display device including a substrate; a
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`f1rstlight-emitting element disposed on the substrate; an encapsulation layer disposed on the first
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`light-emitting element; a diffraction pattern layer disposed on the encapsulation layer; and an
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`input sensing layer disposed on the diffraction pattern layer. The diffraction pattern layer may
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`include a plurality of diffraction patterns arranged to have a first period in one direction.
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`[0014] An exemplary embodiment also discloses a display device including a substrate; a
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`f1rstlight-emitting element disposed on the substrate; an encapsulation layer disposed on the first
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`light-emitting element; an input sensing layer disposed on the encapsulation layer; and a
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`diffraction pattern layer including a plurality of diffraction patterns disposed on an optical path
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`of light emitted from the first light-emitting element. The diffraction patterns may be arranged to
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`have a first period in one direction; and when a cross-sectional width of one of the diffraction
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`patterns may be defined as a first length; the first period and the first length satisfy the following
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`equation: O.4£dl/DP1<1; where DP denotes the first period and d1 denotes the first length.
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`[0015] According to the aforementioned and other exemplary embodiments of the
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`inventive concept; the effective light-emitting area ratio can be increased.
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`[0016] Also; the visibility of blurring can be minimized.
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`[0017] Other features and exemplary embodiments may be apparent from the following
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`detailed description; the drawings; and the claims.
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`[0018] The foregoing general description and the following detailed description are
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`exemplary and explanatory and are intended to provide further explanation of the claimed
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`subject matter.
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`BRIEF DESCRIPTION OF THE DRAWINGS
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`[0019] The accompanying drawings, which are included to provide a further
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`understanding of the inventive concept, and are incorporated in and constitute a part of this
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`specification, illustrate exemplary embodiments of the inventive concept, and, together with the
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`description, serve to explain principles of the inventive concept.
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`[0020] FIG. 1 is a cross-sectional view of a display device according to an exemplary
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`embodiment of the inventive concept.
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`[0021] FIG. 2 is a cross-sectional view illustrating a display panel and a diffraction
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`pattern layer according to the exemplary embodiment of FIG. 1.
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`[0022] FIG. 3 shows a plan view and a cross-sectional view of a first pixel unit of FIG. 2.
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`[0023] FIG. 4 is a perspective view illustrating a first encapsulation layer and the
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`diffraction pattern layer of FIG. 2.
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`[0024] FIG. 5 is a plan view illustrating the first encapsulation layer and the diffraction
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`pattern layer of FIG. 4.
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`[0025] FIG. 6 is a cross-sectional view taken along line 12-12’ of FIG. 5.
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`[0026] FIG. 7 is a cross-sectional view taken along a first imaginary line cll of FIG. 6.
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`[0027] FIG. 8 shows how the light-emitting area of the display device of FIG. 1 can be
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`expanded.
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`[0028] FIG. 9A and FIG. 9B show an increase in the effective light-emitting area ratio of
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`the display device of FIG. 1.
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`[0029] FIG. 10A and FIG. lOB show a cross-sectional region taken along line 12-12’ of
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`FIG. 5.
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`[0030] FIG. 11A, FIG. 11B, and FIG. llC show graphs indicating the luminances of a
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`reference emission pattern and first and fifth duplicated emission patterns of FIG. 8 for different
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`colors.
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`[0031] FIG. 12A, FIG. 12B, and FIG. 12C show graphs obtained by normalizing the
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`luminances of the first and fifth duplicated emission patterns of FIG. 8 with respect to the
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`luminance of the reference emission pattern of FIG. 8.
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`[0032] FIG. 13A is a graph showing the variation of luminance in accordance with An tl
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`when a first organic light-emitting element emits blue light, FIG. 13B is a graph showing the
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`variation of luminance in accordance with An t1 when the first organic light-emitting element
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`emits green light, and FIG. 13C is a graph showing the variation of luminance in accordance
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`with An t1 when the first organic light-emitting element emits red light.
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`[0033] FIG. 14A is a graph showing normalized luminance in accordance with An t1
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`when a first organic light-emitting element emits blue light, FIG. 14B is a graph showing the
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`normalized luminance in accordance with An t1 when the first organic light-emitting element
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`emits green light, and FIG. 14C is a graph showing the normalized luminance in accordance with
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`An t1 when the first organic light-emitting element emits red light.
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`[0034] FIG. 15 is a cross-sectional view showing factors that affect a first diffraction
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`distance.
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`[0035] FIG. 16 is a plan view illustrating the arrangement of pixel units included in the
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`display panel of FIG. 2.
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`[0036] FIG. 17 is a cross-sectional view illustrating an input sensing layer according to
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`an exemplary embodiment of the inventive concept.
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`[0037] FIG. 18 is a plan view of the input sensing layer of FIG. 17.
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`[0038] FIG. 19A is a plan view of a first conductive layer of FIG. 17.
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`[0039] FIG. 19B is a plan view of a second conductive layer of FIG. 17.
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`[0040] FIG. 20 is an exemplary cross-sectional view taken along line II-II’ of FIG. 18.
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`[0041] FIG. 21 is another exemplary cross-sectional view taken along line II—II’ of FIG.
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`18.
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`[0042] FIG. 22 is a cross-sectional view of a display device including an input sensing
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`layer according to another exemplary embodiment of the inventive concept and a diffraction
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`pattern layer according to another exemplary embodiment of the inventive concept.
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`[0043] FIG. 23 is a cross-sectional view of the input sensing layer of FIG. 22.
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`[0044] FIG. 24, FIG. 25, FIG. 26, FIG. 27, FIG. 28, and FIG. 29 are cross-sectional
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`views illustrating input sensing layers according to other exemplary embodiments of the
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`inventive concept.
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`[0045] FIG. 30 is a cross-sectional view of a display device including a display panel
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`according to another exemplary embodiment of the inventive concept.
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`[0046] FIG. 31 is a cross-sectional view showing factors in the display device of FIG. 30
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`that determine a diffraction distance.
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`[0047] FIG. 32 is a plan view of an input sensing layer according to another exemplary
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`embodiment of the inventive concept.
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`[0048] FIG. 33 is a cross-sectional view of the input sensing layer of FIG. 32.
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`[0049] FIG. 34 is a cross-sectional view of an input sensing layer according to another
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`exemplary embodiment of the inventive concept.
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`[0050] FIG. 35 is a cross-sectional view of a display device including an input sensing
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`layer according to another exemplary embodiment of the inventive concept and a diffraction
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`pattern layer according to another exemplary embodiment of the inventive concept.
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`[0051] FIG. 36 is a cross-sectional view of a display device including an input sensing
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`layer according to another exemplary embodiment of the inventive concept and a diffraction
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`pattern layer according to another exemplary embodiment of the inventive concept.
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`[0052] FIG. 37 is a cross-sectional view of a display device including a display panel
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`according to another exemplary embodiment of the inventive concept.
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`[0053] FIG. 38 is a cross-sectional view of a display device including an input sensing
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`layer according to another exemplary embodiment of the inventive concept and a diffraction
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`pattern layer according to another exemplary embodiment of the inventive concept.
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`[0054] FIG. 39 and FIG. 40 are cross-sectional views of display devices according to
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`[0055] FIG. 41A, FIG. 41B, FIG. 41C, FIG. 41D, FIG. 41E, and FIG. 4lF are cross-
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`sectional views of display devices according to other exemplary embodiments of the inventive
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`concept.
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`[0056] FIG. 42A, FIG. 42B, FIG. 42C, FIG. 42D, FIG. 42E, FIG. 42F, and FIG. 42G are
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`cross-sectional views of display devices according to other exemplary embodiments of the
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`inventive concept.
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`[0057] FIG. 43A, FIG. 43B, FIG. 43C, FIG. 43D, FIG. 43E, and FIG. 43F are cross-
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`sectional views of display devices according to other exemplary embodiments of the inventive
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`concept.
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`[0058] FIG. 44A, FIG. 44B, FIG. 44C, FIG. 44D, FIG. 44E, and FIG. 44F are cross-
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`sectional views of display devices according to other exemplary embodiments of the inventive
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`concept.
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`[0059] FIG. 45A is a cross-sectional view of a display device according to another
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`exemplary embodiment of the inventive concept.
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`[0060] FIG. 45B is a cross-sectional view of a display device according to another
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`exemplary embodiment of the inventive concept.
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`[0061] FIG. 46, FIG. 47, FIG. 48, FIG. 49, and FIG. 50 are cross-sectional views of
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`display devices according to other exemplary embodiments of the inventive concept.
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`[0062] FIG. 51 is a perspective view of a diffraction pattern layer according to another
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`exemplary embodiment of the inventive concept.
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`[0063] FIG. 52 is a plan view of the diffraction pattern layer of FIG. 51.
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`[0064] FIG. 53 is a cross-sectional view taken along line I3-I3’ of FIG. 52.
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`[0065] FIG. 54 is a cross-sectional view taken along a second imaginary line c12 of FIG.
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`[0066] FIG. 55 is a plan view of a diffraction pattern layer according to another
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`exemplary embodiment of the inventive concept.
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`[0067] FIG. 56A is a cross-sectional view of a diffraction pattern layer according to
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`another exemplary embodiment of the inventive concept, and FIG. 56B is a cross-sectional view
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`taken along a third imaginary line cl3 of FIG. 56A.
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`[0068] FIG. 57A is a cross-sectional view of a diffraction pattern layer according to
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`another exemplary embodiment of the inventive concept, and FIG. 57B is a cross-sectional view
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`taken along a fourth imaginary line cl4 of FIG. 57A.
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`[0069] FIG. 58 and FIG. 59 are plan views illustrating the pixel arrangements of display
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`device according to other exemplary embodiment of the inventive concept.
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`DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODHVIENTS
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`[0070] In the following description, for the purposes of explanation, numerous specific
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`details are set forth in order to provide a thorough understanding of various exemplary
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`embodiments. It is apparent, however, that various exemplary embodiments may be practiced
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`without these specific details or with one or more equivalent arrangements.
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`In other instances,
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`well-known structures and devices are shown in block diagram form in order to avoid
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`unnecessarily obscuring various exemplary embodiments.
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`[0071] In the accompanying figures, the size and relative sizes of layers, films, panels,
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`regions, etc., may be exaggerated for clarity and descriptive purposes. Also, like reference
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`numerals denote like elements.
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`[0072] When an element or layer is referred to as being "on,
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`connected to," or "coupled
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`to" another element or layer, it may be directly on, connected to, or coupled to the other element
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`or layer or intervening elements or layers may be present. When, however, an element or layer is
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`referred to as being "directly on," "directly connected to," or "directly coupled to" another
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`element or layer, there are no intervening elements or layers present. For the purposes of this
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`disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of
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`X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of
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`X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. Like numbers refer to like elements
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`throughout. As used herein, the term "and/or" includes any and all combinations of one or more
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`of the associated listed items.
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`[0073] Although the terms first, second, etc. may be used herein to describe various
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`elements, components, regions, layers, and/or sections, these elements, components, regions,
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`layers, and/or sections should not be limited by these terms. These terms are used to distinguish
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`one element, component, region, layer, and/or section from another element, component, region,
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`layer, and/or section. Thus, a first element, component, region, layer, and/or section discussed
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`below could be termed a second element, component, region, layer, and/or section without
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`departing from the teachings of the inventive concept.
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`[0074] Spatially relative terms, such as "beneath," "below," "lower,
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`above,
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`upper,"
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`and the like, may be used herein for descriptive purposes, and, thereby, to describe one element
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`or feature's relationship to another element(s) or feature(s) as illustrated in the drawings.
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`Spatially relative terms are intended to encompass different orientations of an apparatus in use,
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`operation, and/or manufacture in addition to the orientation depicted in the drawings. For
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`example, if the apparatus in the drawings is turned over, elements described as "below" or
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`"beneath" other elements or features would then be oriented "above" the other elements or
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`features. Thus, the exemplary term "below" can encompass both an orientation of above and
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`below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at
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`other orientations), and, as such, the spatially relative descriptors used herein interpreted
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`accordingly.
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`[0075] The terminology used herein is for the purpose of describing particular
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`embodiments and is not intended to be limiting. As used herein, the singular forms,
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`a,
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`an,
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`and "the" are intended to include the plural forms as well, unless the context clearly indicates
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`otherwise. Moreover, the terms "comprises,
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`comprising,
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`1ncludes," and/or "including," when
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`used in this specification, specify the presence of stated features, integers, steps, operations,
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`elements, components, and/or groups thereof, but do not preclude the presence or addition of one
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`or more other features, integers, steps, operations, elements, components, and/or groups thereof.
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`[0076] Various exemplary embodiments are described herein with reference to sectional
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`illustrations that are schematic illustrations of idealized exemplary embodiments and/or
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`intermediate structures. As such, variations from the shapes of the illustrations as a result, for
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`example, of manufacturing techniques and/or tolerances, are to be expected. Thus, exemplary
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`embodiments disclosed herein should not be construed as limited to the particular illustrated
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`shapes of regions, but are to include deviations in shapes that result from, for instance,
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`manufacturing. The regions illustrated in the drawings are schematic in nature and their shapes
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`are not intended to illustrate the actual shape of a region of a device and are not intended to be
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`limiting.
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`[0077] Unless otherwise defined, all terms (including technical and scientific terms) used
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`herein have the same meaning as commonly understood by one of ordinary skill in the art to
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`which this disclosure is a part. Terms, such as those defined in commonly used dictionaries,
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`should be interpreted as having a meaning that is consistent with their meaning in the context of
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`the relevant art and will not be interpreted in an idealized or overly formal sense, unless
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`expressly so defined herein.
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`[0078] Hereinafter, exemplary embodiments will be described with reference to the
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`accompanying drawings.
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`[0079] FIG. 1 is a schematic cross-sectional view of a display device according to an
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`exemplary embodiment of the inventive concept.
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`[0080] Referring to FIG. 1, the display device may include a display panel 100, a
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`diffraction pattern layer 200, an input sensing layer 300, an anti-reflection panel 400, and a
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`window panel 500.
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`[0081] In the description that follows, elements formed by a continuous process may be
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`collectively referred to as a “layer”, and elements coupled to one another via another element or
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`an adhesive member may be collectively referred to as a “panel”. A panel includes a base layer
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`providing a base surface, but a layer may not include any base layer. That is, a layer denotes one
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`or more elements disposed on a base surface provided by another element. Examples of a base
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`layer may include a synthetic resin film, a composite film, and a glass substrate.
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`[0082] Accordingly, in a case where the input sensing layer 300 includes a base layer, the
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`input sensing layer 300 may also be referred to as an input sensing panel. Also, in a case where
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`the anti-reflection panel 400 and the window panel 500 do not include a base layer, the anti-
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`refiection panel 400 and the window panel 500 may also be referred to as an anti-reflection layer
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`and a window layer, respectively.
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`[0083] The display panel 100 generates an image. In one exemplary embodiment, the
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`display panel 100 may be an emissive display panel. Specifically, the display panel 100 may be
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`an organic light-emitting display panel. However, the type of the display panel 100 is not
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`particularly limited. That is, the display panel 100 may be a quantum dot display panel or a
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`liquid crystal display (LCD) panel. The display panel 100 will hereinafter be described, taking
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`an organic light-emitting display panel.
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`[0084] A display panel including a first encapsulation layer 160 will hereinafter be
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`referred to as the display panel 100. A display panel including a second encapsulation layer 170
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`will hereinafter be referred to as a display panel 101 (or 102).
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`[0085] Referring to FIG. 1, although not specifically illustrated, the display device may
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`include a protective member, which is disposed below the display panel 100.
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`In one exemplary
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`embodiment, the protective member may be coupled to the display panel 100 by an adhesive
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`member. The material of the adhesive member is not particularly limited.
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`In one exemplary
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`embodiment, the adhesive member may be an optically clear adhesive (OCA) or optically clear
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`resin (OCR) member or a pressure sensitive adhesive (PSA) member.
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`[0086] The diffraction pattern layer 200 may be disposed on the display panel 100.
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`Specifically, the diffraction pattern layer 200 may be disposed on the optical path of light emitted
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`from a plurality of display elements included in the display panel 100. In one exemplary
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`embodiment, the display elements may be organic light-emitting elements. The location of the
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`diffraction pattern layer 200 is not particularly limited as long as the diffraction pattern layer 200
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`is positioned on the optical path of light emitted from the display elements included in the
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`display panel 100.
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`[0087] The diffraction pattern layer 200 may include a plurality of diffraction patterns
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`210 and a first passivation layer 220. In one exemplary embodiment, the diffraction patterns 210
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`may be disposed directly on the display panel 100. That is, an additional adhesive member may
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`not be disposed between the diffraction patterns 210 and the display panel 100.
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`In one
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`exemplary embodiment, the diffraction patterns 210 may be formed on the display panel 100
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`through a continuous process.
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`[0088] The diffraction patterns 210 may expand the light-emitting area of the display
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`device by diffracting light emitted from the display panel 100. This will be described later with
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`reference to FIG. 8. In one exemplary embodiment, the diffraction patterns 210 may be patterns
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`having periodicity. The periodicity and the shape of the diffraction patterns 210 will be
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`described later with reference to FIGS. 4 through 6.
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`[0089] The first passivation layer 220 may be disposed on the diffraction patterns 210.
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`In one exemplary embodiment, the first passivation layer 220 may be formed to cover the
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`diffraction patterns 210. The material of the f1rstpassivation layer 220 is not particularly
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`limited. In one exemplary embodiment, the f1rstpassivation layer 220 may be formed of an
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`organic film or an inorganic film. The organic film may comprise at least one of an acrylic resin,
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`a methacrylic resin, polyisoprene, a vinyl resin, an epoxy resin, a urethane resin, a cellulose
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`resin, a siloxane resin, a polyimide (PI) resin, and a perylene resin. The inorganic film may
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`comprise at least one of aluminum oxide, titanium oxide, silicon oxide, silicon oxynitride,
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`zirconium oxide, and hafnium oxide. The f1rstpassivation layer 220 may be replaced with an air
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`layer.
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`[0090] The input sensing layer 300 may be disposed on the diffraction pattern layer 200.
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`In one exemplary embodiment, the input sensing layer 300 may be formed on the first
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`passivation layer 220 through a continuous process. The input sensing layer 300 may obtain
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`coordinate information from an external input such as, for example, a touch input. That is, the
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`input sensing layer 300 may be a touch panel that senses a user’s touch, or a fingerprint sensing
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`panel that acquires fingerprint information from a user’s f1nger.
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`[0091] In one exemplary embodiment, the input sensing layer 300 may sense an external
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`input in a capacitive manner. The type of input sensing method used by the input sensing layer
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`300 is not particularly limited. In one exemplary embodiment, the input sensing layer 300 may
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`sense an external input using an electromagnetic induction method or a pressure sensing method.
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`[0092] FIG. 1 illustrates that the input sensing layer 300 generally overlaps with the
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`display panel 100, but the inventive concept is not limited thereto. That is, the input sensing
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`layer 300 may overlap with only part of the display panel 100, for example, at least part of a
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`display area for displaying an image. Alternatively, the input sensing layer 300 may overlap
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`with a non-display area that does not display an image.
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`[0093] The anti-reflection panel 400 may be disposed on the input sensing layer 300. In
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`one exemplary embodiment, the anti-reflection panel 400 may be coupled to the input sensing
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`layer 300 via a first adhesive member 610. In one exemplary embodiment, the first adhesive
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`member 610 may be a PSA member, but the inventive concept is not limited thereto. That is,
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`alternatively, the first adhesive member 610 may be an OCA member. Still alternatively, the
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`first adhesive member 610 may be an OCR member.
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`[0094] The anti-reflection panel 400 may reduce the reflectance of external light incident
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`thereupon from the top of the window panel 500.
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`In one exemplary embodiment, the anti-
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`refiection panel 400 may include a retarder and a polarizer.
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`[0095] In one exemplary embodiment, the retarder may be of a film type or a liquid
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`crystal coating type. The retarder may include a M2 retarder and/or a N4 retarder. In one
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`exemplary embodiment, the polarizer may be of a film type or a liquid crystal coating type. The
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`film-type polarizer may be a stretch-type synthetic resin film. The liquid-crystal-coating-type
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`polarizer may include liquid crystal molecules arranged in a predetermined manner. In one
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`exemplary embodiment, the retarder and the polarizer may further include a protective film. The
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`retarder and the polarizer may be defined as the base layer of the anti-reflection panel 400. If the
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`retarder and the polarizer further include a protective film, the protective film may be defined as
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`the base layer of the anti-reflection panel 400.
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`[0096] The window panel 500 may be disposed on the anti-reflection panel 400. In one
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`exemplary embodiment, the window panel 500 and the anti-reflection panel 400 may be coupled
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`to each other via a second adhesive member 620. In one exemplary embodiment, the second
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`adhesive member 620 may be a PSA member, but the inventive concept is not limited thereto.
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`That is, alternatively, the second adhesive member 620 may be an OCA member. Still
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`alternatively, the second adhesive member 620 may be an OCR member.
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`[0097] The order in which the diffraction pattern layer 200, the input sensing layer 300,
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`the anti-reflection panel 400, and the window panel 500 are stacked is not limited to that
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`illustrated in FIG. 1, and this will be described later in detail.
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`[0098] FIG. 1 illustrates an example in which the diffraction pattern layer 200, the input
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`sensing layer 300, the anti-reflection panel 400, and the window panel 500 are disposed on the
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`display panel 100, but the inventive concept is not limited thereto. That is, in another example,
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`the diffraction pattern layer 200, the input sensing layer 300, the anti-reflection panel 400, and
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`the window panel 500 may be disposed on the display panel 101 (or 102).
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`[0099] The order in which the diffraction pattern layer 200, the input sensing layer 300,
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`and the window panel 500 are stacked may vary. The display panel 100, including the first
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`encapsulation layer 160 and the diffraction pattern layer 200, will hereinafter be described. For
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`convenience, the input sensing layer 300, the anti-reflection panel 400, and the window panel
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`500 are omitted from FIGS. 2 through 16.
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`[0100] FIG. 2 is a cross-sectional view illustrating a display panel and a diffraction
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`pattern layer according to the exemplary embodiment of FIG. 1. FIG. 3 shows a plan view and a
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`cross-sectional view of a first pixel unit of FIG. 2.
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`[0101] Referring to FIGS. 2 and 3, the display panel 100 may include a first substrate
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`110, a plurality of pixel electrodes 120, which include a first pixel electrode 121, a pixel defining
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`film 130, a plurality of organic light-emitting elements 140, which include a first organic light-
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`emitting element 141, a common electrode 150, a first buffer layer 151, and the first
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`encapsulation layer 160. A pixel unit including the first pixel electrode 121 and the first organic
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`light-emitting element 141 will hereinafter be referred to as a first pixel unit PXl.
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`[0102] In one exemplary embodiment, the first substrate 110 may be an insulating
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`substrate. The first substrate 110 may be formed of glass, quartz, or a polymer resin. The
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`material of the polymer resin may be polyethersulphone (PES), polyacrylate (PA), polyarylate
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`(PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET),
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`polyphenylenesulfide (PPS), polyallylate, PI, polycarbonate (PC), cellulose triacetate (CAT),
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`cellulose acetate propionate (CAP), or a combination thereof. In another exemplary
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`embodiment, the first substrate 110 may be a flexible substrate comprising PI.
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`[0103] The pixel electrodes 120 may be disposed on the first substrate 110. Although not
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`specifically illustrated, a plurality of elements may be further provided between the first substrate
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`110 and the pixel electrodes 120. The plurality of elements may include a buffer layer, a
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`plurality of conductive wires, an insulating layer, and a plurality of thin film transistors (TFTs).
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`The TFTs may use amorphous silicon, polysilicon, low temperature polysilicon (LTPS), an oxide
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`semiconductor, or an organic semiconductor as their channel layer. The type of the channel
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`layer may differ from one TFT to another TFT. In one exemplary embodiment, a TFT
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`comprising an oxide semiconductor and a TFT comprising LTPS may both be included in a
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`single pixel unit in consideration of the functions of the TFTs or the order of processes.
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`[0104] The pixel electrode 120 will hereinafter be described, taking the first pixel
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`electrode 121. In one exemplary embodiment, the first pixel electrode 121 may be an anode
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`electrode. In a case where the first pixel electrode 121 is an anode electrode, the first pixel
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`electrode 121 may comprise a reflective material. In one exemplary embodiment, the reflective
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`material may include at least one reflective film formed of a material selected from the group
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`consisting of silver (Ag), magnesium (Mg), chromium (Cr), gold (Au), platinum (Pt), nickel
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`(Ni), copper (Cu), tungsten (W), and aluminum (Al) and a transparent or translucent electrode
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`formed on the reflective film.
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`[0105] The transparent or translucent electrode may comprise at least one selected from
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`the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO),
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`indium oxide (In203), indium gallium oxide (IGO), and aluminum zinc oxide (AZO).
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`[0106] The pixel defining film 130 may be disposed on the first pixel electrode 121. The
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`pixel defining film 130 includes an opening 0P1 exposing at least part of the first pixel electrode
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`121. The pixel defining film 130 may comprise an organic material or an inorganic material. In
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`one exemplary embodiment, the pixel defining film 130 may comprise a material such as a
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`photoresist, a PI resin, an acrylic resin, a silicon compound, or a polyacrylic resin.
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`[0107] In one exemplary embodiment, the shape of the first pixel electrode 121 may be
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`rhombic. In one exemplary embodiment, the shape of an opening 0P1 of the pixel defining film
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`130 may also be rhombic. However, the shape of the first pixel electrode 121 and the shape of
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`the opening 0P1 of the pixel defining film 130 are not particularly limited. That is, the shape of
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`the first pixel electrode 121 and the shape of the opening 0P1 of the pixel defining film 130 may
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`vary depending on the arrangement of a plurality of pixel units.
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`[0108] The organic light-emitting elements 140 may be disposed on the pixel electrodes
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`120 and the pixel defining film 130. The organic light-emitting elements 140 will hereinafter be
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`described, taking the first organic light-emitting element 141. The first organic light-emitting
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`element 141 may be disposed on part of the first pixel electrode 121 exposed by the opening 0P1
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`of the pixel defining film 130. That is, the first organic light-emitting element 141 may overlap
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`with the opening 0P1 of the pixel defining film 130.
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`In one exemplary embodiment, the first
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`organic light-emitting element 141 may cover at least part of the opening 0P1 of the pixel
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`defining film 130.
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`[0109] In one exemplary embodiment, the first organic light-emitting element 141 may
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`emit one of red light, green light, and blue light. The wavelength of the red light may range from
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`about 620 nm to 750 nm, the wavelength of the gree