Patent Description:
There is a growing need for personal authentication using unique personal features such as fingerprints, voice, face, hands, or an iris. Such personal authentication has been mainly used in financial devices, access control systems, mobile devices, laptop computers, etc. Recently, as mobile devices such as smart phones, tablet personal computers (PCs), and smart watches have come into more widespread use, a fingerprint recognition device has been employed to perform personal authentication so as to protect a large amount of security information stored in a mobile devices.

For design purposes or user convenience, display apparatuses including a fingerprint recognition device capable of directly performing fingerprint recognition on a display panel have been developed. Such a display apparatus has a structure in which a display panel with a pixel pattern having a regular arrangement of pixels and a fingerprint sensor with a sensor pattern having a regular arrangement of electrodes are vertically stacked. In this case, the pixel pattern and the sensor pattern may overlap each other and thus a moiré pattern may occur due to interference between the pixel pattern and the sensor pattern. The moiré pattern may distort an image and thus display quality may be degraded.

<CIT> discloses a touch panel, comprising a substrate, a sensing layer disposed on the substrate, and an optical matching glue disposed on the sensing layer.

<CIT> discloses a touch substrate, a preparation method thereof, and a display device.

<CIT> discloses an optoelectronic modulation stack including a substrate, a plurality of touch sensing units, at least a first anti-interference spot, and a nano-structural layer.

<CIT> discloses an electrostatic capacitive type window integrated touch screen panel, and a method of manufacturing a touch screen panel thereof.

<CIT> discloses a touch screen configured to have an array of conductive, optically transmissive sensor elements coupled to sensor circuitry. The sensor elements are disposed over a display to have a single layer of conductive, optically transmissive material positioned over pixels of the display. <CIT> discloses a touchscreen system configured to detect touches on a portion of the touchscreen and to read fingerprint on another portion of the touchscreen.

One or more example embodiments may provide a display apparatus for preventing the appearance of a moiré pattern.

Additional example aspects and advantages will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented example embodiments.

According to an aspect of the invention, a display apparatus is provided in accordance with claim <NUM>.

These and/or other example aspects and advantages will become apparent and more readily appreciated from the following description of example embodiments, taken in conjunction with the accompanying drawings in which:.

Reference will now be made in detail to example embodiments which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In the drawings, the size of each element may be exaggerated for clarity and for convenience of explanation. Embodiments set forth herein are merely examples and various changes may be made therein.

It will be further understood that when an element or layer is referred to as "including" another element or layer, the element or layer may further include other elements or layers unless mentioned otherwise. The term "the" and other demonstratives similar thereto should be understood to include a singular form and plural forms.

<FIG> illustrates a pattern structure for preventing the visibility of a moiré pattern. <FIG> is an enlarged view of a part of the pattern structure of <FIG>.

Referring to <FIG>, a pattern structure <NUM> includes a first element pattern having a plurality of first elements <NUM>, a second element pattern provided on the first element pattern and having a plurality of second elements <NUM>, and a filling layer <NUM> provided among the second elements <NUM>. In the first element pattern, the first elements <NUM> are regularly arranged at a first pitch P1. In the second element pattern, the second elements <NUM> are regularly arranged at a second pitch P2.

A transparent substrate <NUM> may be provided between the first element pattern and the second element pattern. The first element pattern may be provided on a bottom surface of the substrate <NUM>. The second element pattern may be provided on a top surface of the substrate <NUM>.

The filling layer <NUM> may fill gaps among the second elements <NUM> of the second element pattern. The filling layer <NUM> may be provided among the second elements <NUM>, between adjacent ones thereof. The filling layer <NUM> may be formed to a same height as or to a lower height than that of the second elements <NUM>.

The first pitch P1 of the first element pattern and the second pitch P2 of the second element pattern may be values at which a moiré pattern occurring due to the overlapping of the first element pattern and the second element pattern becomes visible when the filling layer <NUM> is not provided.

In a high-resolution display apparatus having a fingerprint sensor, the first pitch P1 of the first element pattern is equal to a pitch of a pixel pattern and the second pitch P2 of the second element pattern is equal to a pitch of an electrode pattern. In this case, the first pitch P1 of the first element pattern is <NUM> or less. The second pitch P2 of the second element pattern may be a value, e.g., about <NUM> or less, at which a moiré pattern becomes visible due to the overlapping of the second element pattern and the first element pattern. The second pitch P2 of the second element pattern is <NUM> or less, similar to the first pitch P1 of the first element pattern.

The filling layer <NUM> provided among the second elements <NUM>, between adjacent ones thereof, prevents the visibility of the moiré pattern which may occur due to the overlapping of the first and second element patterns. To this end, the difference between transmittances (or reflectances) of the second elements <NUM> and the filling layer <NUM> is <NUM>% or less.

Some of the light incident on the second elements <NUM> may pass through the second elements <NUM> and another part of the incident light may be reflected by the second elements <NUM>. Furthermore, some of the light incident on the filing layer <NUM>, provided among the second elements <NUM>, may pass through the filling layer <NUM> and another part of the incident light may be reflected by the filling layer <NUM>. In <FIG>, T<NUM> represents light passing through the second elements <NUM>, R<NUM> represents light reflected by the second elements <NUM>, T<NUM> represents light passing through the filling layer <NUM>, and R<NUM> represents light reflected by the filling layer <NUM>.

When the transmittance of the second element <NUM> and the transmittance of the filling layer <NUM> are similar, the second element pattern is not visible. When a difference between the transmittances of the second element <NUM> and the filling layer <NUM> is <NUM>% or less, the second element <NUM> and the filling layer <NUM> cannot be distinguished from each other by the naked eye and thus the second element pattern is not visible. If the second element pattern is not visible as described above, a moiré pattern is not visible even when the first element pattern and the second element pattern overlap each other.

A case in which the filling layer <NUM> having similar transmittance to those of the second elements <NUM> is provided among the second elements <NUM> to prevent the visibility of the moiré pattern has been described above. However, even when a filling layer (not shown) having similar transmittance to those of the first elements <NUM> is provided among the first elements <NUM>, the visibility of the moiré pattern may be prevented.

The second element <NUM> includes an oxide-metal-oxide (OMO) material. In detail, the second element <NUM> includes a first oxide layer <NUM>, a metal layer <NUM> and a second oxide layer <NUM> (i.e., a first oxide layer/metal layer/second oxide layer) which are sequentially stacked. The OMO material may have a transmittance of <NUM>% or more and a sheet resistance of <NUM>Ω sq-<NUM> or less.

The first oxide layer <NUM> may include an oxide having a refractive index of about <NUM> to <NUM> and a thickness of about <NUM> to <NUM>. As a concrete example, the first oxide layer <NUM> may include, but is not limited to, at least one material from among an indium-tin oxide (ITO), an indium-zinc oxide (IZO), an Al-doped ZnO (AZO), a Ga-doped ZnO (GZO), an indium-tin-zinc oxide (ITZO), a zinc-tin oxide (ZTO), an indium-gallium oxide (IGO), SnO<NUM>, TiO<NUM>, Nb<NUM>O<NUM>, ZnO, ZrO<NUM> and HfO<NUM>.

The metal layer <NUM> may have a thickness less than that of each the first and second oxide layers <NUM> and <NUM>, e.g., a thickness of about <NUM> to <NUM>. As a concrete example, the metal layer <NUM> may include Ag or an Ag alloy. Here, the Ag alloy may include, but is not limited to, a binary metal system such as Ag-Al, Ag-Mo, Ag-Au, Ag-Pd, Ag-Ti, or Ag-Cu or a ternary metal system such as Ag-Au-Pd or Ag-Au-Cu.

The second oxide layer <NUM> may include the same material as the first oxide layer <NUM> or a material having a lower refractive index than that of the first oxide layer <NUM>. The second oxide layer <NUM> may include an oxide having a refractive index of about <NUM> to <NUM> and a thickness of about <NUM> to <NUM>. As a concrete example, the second oxide layer <NUM> may include at least one material from among an indium-tin oxide (ITO), an indium-zinc oxide (IZO), an Al-doped ZnO (AZO), a Ga-doped ZnO (GZO), an indium-tin-zinc oxide (ITZO), a zinc-tin oxide (ZTO), an indium-gallium oxide (IGO), SnO<NUM>, and ZnO, but is not limited thereto.

As described above, the filling layer <NUM> provided among the second elements <NUM> may include a material having similar transmittance to that of the second elements <NUM> to prevent the visibility of the second element pattern. In detail, when the second elements <NUM> include an OMO material, the filling layer <NUM> may include an insulating material having a refractive index of about <NUM> to <NUM>. As a concrete example, the filling layer <NUM> may include an inorganic oxide such as MgO, Ta<NUM>O<NUM>, SiON, or SiO<NUM> or an inorganic insulating material.

<FIG> is a graph showing transmittances of TiO<NUM>/Ag/ITO and SiO<NUM>. Referring to <FIG>, TiO<NUM>/Ag/ITO, which is an OMO material, was used at thicknesses of <NUM>, <NUM> and <NUM>, and SiO<NUM> was used at a thickness of <NUM>. Referring to <FIG>, both TiO<NUM>/Ag/ITO and SiO<NUM> had a transmittance of <NUM>% or more, and the transmittance of TiO<NUM>/Ag/ITO and the transmittance of SiO<NUM> were substantially the same. Thus, when, in the pattern structure <NUM> of <FIG>, the second elements <NUM> are TiO<NUM>/Ag/ITO and the filing layer <NUM> provided among the second elements <NUM> is SiO<NUM>, the difference between the transmittances of TiO<NUM>/Ag/ITO and SiO<NUM> is small and thus the second element pattern may not be visible.

As described above, in the pattern structure <NUM>, the filing layer <NUM> having similar transmittance to those of the second elements <NUM> is provided among the second elements <NUM> of the second element pattern, between adjacent ones thereof, and thus the second element pattern is not visible. Accordingly, the visibility of the moiré pattern, which may occur due to the overlapping of the first element pattern and the second element pattern, is prevented.

<FIG> illustrate real-space patterns for explaining cases in which the moiré pattern is visible. <FIG> illustrate spatial frequency vector distributions in which the patterns of <FIG> are expressed through Fourier transform. In <FIG>, u and v represent directions, and f<NUM> and f<NUM> respectively represent a first-direction frequency vector and a second-direction frequency vector. Furthermore, the visibility circle represents a critical pattern pitch (corresponding to <NUM> cycles/degrees) of a pattern distinguishable by a human eye. When a frequency vector is located outside the visibility circle, it is difficult for the frequency vector to be distinguished by the human eye, and thus is not recognized as a pattern.

<FIG> illustrates a first pattern A formed in a vertical direction. <FIG> illustrates a first spatial frequency vector distribution A' in which the first pattern A of <FIG> is expressed through Fourier transform. <FIG> illustrates a second pattern B tilted at a certain angle with respect to the vertical direction. <FIG> illustrates a second spatial frequency vector distribution B' in which the second pattern B of <FIG> is expressed through Fourier transform. In this case, the pitch of the first pattern A and the pitch of the second pattern B may be similar.

<FIG> illustrates a third pattern C formed by overlapping the first pattern A of <FIG> and the second pattern B of <FIG> with each other. <FIG> illustrates a third spatial frequency vector distribution C' obtained from the convolution sum of frequency vectors illustrated in <FIG> and frequency vectors illustrated in <FIG>.

Referring to <FIG>, the moiré pattern is visible in the third pattern C formed by overlapping the first pattern A and the second pattern B having similar pitches. The visibility of the moiré pattern may be also known from the third spatial frequency vector distribution C' of <FIG>, in which frequency vectors corresponding to the moiré pattern are located inside a visibility circle. As described above, the moiré pattern is visible when the first pattern A and the second pattern B having similar pitch overlap each other.

<FIG> illustrate real-space patterns for explaining cases in which a moiré pattern is not visible. <FIG> illustrate spatial frequency vector distributions in which the patterns of <FIG> are expressed through Fourier transform. In <FIG>, u and v represent directions, and f<NUM> and f<NUM> respectively represent a first-direction frequency vector and a second-direction frequency vector.

<FIG> illustrates a first pattern D formed in the vertical direction. <FIG> illustrates a first spatial frequency vector distribution D' in which the first pattern D of <FIG> is expressed through Fourier transform. <FIG> illustrates a second pattern E tilted at a certain angle with respect to the vertical direction. <FIG> illustrates a second spatial frequency vector distribution E' in which the second pattern E of <FIG> is expressed through Fourier transform. Here, a pitch of the second pattern E may be significantly smaller than that of the first pattern D.

<FIG> illustrates a third pattern F formed by overlapping the first pattern D of <FIG> and the second pattern E of <FIG>. <FIG> illustrates a third spatial frequency vector distribution F' obtained from the convolution sum of frequency vectors illustrated in <FIG> and frequency vectors illustrated in <FIG>.

Referring to <FIG>, frequency vectors of the third spatial frequency vector distribution F' corresponding to the moiré pattern are located outside the visibility circle. Thus, the moiré pattern is not visible from the third pattern F formed by overlapping the first pattern D of <FIG> and the second pattern E of <FIG>. As described above, if the difference between the pitch of first pattern D and the pitch of the second pattern E is large and the second pattern E is formed at a certain angle with respect to the first pattern D, the moiré pattern may not be visible even when the first pattern D and the second pattern E overlap each other.

In the pattern structure <NUM> of <FIG>, even if the first pitch P1 of the first element pattern and the second pitch P2 of the second element pattern are similar, the moiré pattern occurring due to the overlapping of the first element pattern and the second element pattern is prevented from being visible when the filling layer <NUM> having similar transmittance to those of the second elements <NUM> is provided among the second elements <NUM>, between adjacent ones thereof. In detail, when the filling layer <NUM> is provided among the second elements <NUM>, the second element pattern is not optically visible due to the similar transmittances of the second elements <NUM> and the filling layer <NUM>. Thus, since the second element pattern is not visible due to the filling layer <NUM>, the moiré pattern is not visible when the second element pattern overlaps the first element pattern. This may be seen from a fact that frequency vectors corresponding to the moiré pattern in the spatial frequency vector distribution obtained from the convolution sum of the spatial frequency vectors of the first element pattern and the spatial frequency vectors of the second element pattern are not located inside the visibility circle.

For example, in a high-resolution display apparatus such as a smart phone or a smart watch, in which a fingerprint sensor is mounted on a display panel, a pixel pattern of the display panel may have a pitch of about <NUM> or less. When electrode patterns of the fingerprint sensor have a pitch of about <NUM> or less (particularly, a pitch of about <NUM> or less), the moiré pattern occurring due to the overlapping of the pixel pattern and the electrode patterns is visible. In a related art, the pixel pattern and the electrode patterns are aligned with each other to prevent the visibility of the moiré pattern. In contrast, according to the present example embodiment, the visibility of a moiré pattern occurring due to the overlapping of a pixel pattern and electrode patterns is prevented by providing a filling layer having similar transmittance to those of electrode patterns between the electrode patterns without aligning the electrode patterns and the pixel pattern.

<FIG> illustrates a pattern structure for preventing the visibility of a moiré pattern.

Referring to <FIG>, in a pattern structure <NUM>', a first element pattern, having a plurality of first elements <NUM> arranged regularly at a first pitch P1, is provided on a bottom surface of a transparent substrate <NUM>, and a second element pattern, having a plurality of second elements <NUM> arranged regularly at a second pitch P2, is provided on a top surface of the transparent substrate <NUM>.

A filling layer <NUM>' is provided to fill gaps among the second elements <NUM> of the second element pattern, between adjacent ones thereof. Here, the filling layer <NUM>' fills spaces among the second elements <NUM> and may also cover the second elements <NUM>. The filling layer <NUM>' may be formed to have a higher height than the second elements <NUM>. The filling layer <NUM>' has similar transmittance to those of the second elements <NUM> of the second element pattern as described above. In detail, the difference between transmittances (or reflectances) of the second elements <NUM> and the filling layer <NUM>' are <NUM>% or less.

As described above, the first pitch P1 of the first element pattern and the second pitch P2 of the second element pattern may be values at which a moiré pattern occurring due to the overlapping of the first and second element patterns becomes visible when the filling layer <NUM>' is not provided. However, as the filling layer <NUM>' having similar transmittance to that of the second elements <NUM> is provided to fill gaps among the second elements <NUM>, the visibility of the moiré pattern occurring due to the overlapping of the first and second element patterns is prevented.

<FIG> illustrates a display apparatus according to an example embodiment. A display apparatus <NUM> illustrated in <FIG> may be employed, for example, in an electronic device such as a smart phone, a smart watch, a tablet PC, or a laptop computer but is not limited thereto.

Referring to <FIG>, the display apparatus <NUM> includes a display panel <NUM> which displays color images, and a sensor <NUM> provided on the display panel <NUM>. A transparent adhesive layer (not shown), e.g., an optically clear adhesive (OCA) or optically clear resin (OCR), may be provided between the display panel <NUM> and the sensor <NUM>.

The display panel <NUM> may include, for example, an organic light-emitting display panel or a liquid crystal display panel but is not limited thereto. As will be described below, the display panel <NUM> includes a pixel pattern <NUM>, as shown in <FIG> and <FIG>, in which a plurality of pixels PX are regularly arranged at a first pitch P1.

The sensor <NUM> includes a fingerprint sensor or a fingerprint-touch composite sensor. The sensor <NUM> may be a capacitive sensor. The sensor <NUM> may include a sensor part <NUM> and a protective layer <NUM> stacked on a transparent substrate <NUM>. The transparent substrate <NUM> may be a reinforced substrate including, for example, glass, poly(methylmethacrylate) (PMMA), poly carbonate (PC), or polyethylene terephthalate (PET), or the like but is not limited thereto. The sensor part <NUM> may include an electrode pattern in which a plurality of electrodes <NUM> and <NUM> are regularly arranged at a second pitch P2, as will be described below, and as illustrated in <FIG>.

<FIG> illustrates a pixel pattern of a display panel such as that of <FIG>. <FIG> is an enlarged view of a part of the pixel pattern of <FIG>.

Referring to <FIG> and <FIG>, a pixel pattern <NUM> has a structure in which a plurality of pixels PX are regularly arranged at a first pitch P1. Here, each of the pixels PX may include different color subpixels, e.g., red, green, and blue subpixels R, G, and B. Here, the red, green, and blue subpixels R, G, and B may be sequentially arranged in one direction.

<FIG> illustrates another example of a pixel pattern applicable to the display panel <NUM> of <FIG>. Referring to <FIG>, a pixel pattern <NUM>' has a structure in which a plurality of pixels PX are regularly arranged at a first pitch P1. Each of the pixels PX may include different color subpixels, e.g., red, green and blue subpixels R, G, and B. Here, the green subpixel G may be located below the red subpixel R, and the blue subpixel B may be located at a side of the red and green subpixels R and G. Here, the sizes and shapes of the red, green and blue subpixels R, G, and B may be differently set in units of colors for display quality and optimal brightness.

An arrangement of the red, green and blue subpixels R, G, and B described above is merely an example and thus the red, green and blue subpixels R, G, and B may be arranged in any of various other forms. Furthermore, an example in which each of the pixels PX includes the red, green and blue subpixels R, G, and B has been described above but each of the pixels PX may include subpixels of various other colors. For example, each of the pixels PX may include white, cyan, magenta, and yellow subpixels.

<FIG> is a cross-sectional view of a sensor part of a sensor such as that of <FIG>.

Referring to <FIG>, a sensor part <NUM> may include a dielectric layer <NUM>, a first electrode layer <NUM> located on a bottom surface of the dielectric layer <NUM>, and a second electrode layer <NUM> located on a top surface of the dielectric layer <NUM>. The first electrode layer <NUM> may include a first electrode pattern including a plurality of first electrodes <NUM> arranged regularly at a second pitch P2, and a first filling layer <NUM> provided to fill gaps among the first electrodes <NUM>, between adjacent ones thereof. The second electrode layer <NUM> may include a second electrode pattern with a plurality of second electrodes <NUM> arranged regularly at the second pitch P2, and a second filling layer (not shown) provided to fill gaps among the second electrodes <NUM>, between adjacent ones thereof.

<FIG> is a cross-sectional view of the first and second electrodes <NUM> and <NUM> of the sensor part of <FIG>. Referring to <FIG>, the first and second electrodes <NUM> and <NUM> include an oxide-metal-oxide (OMO) material. In detail, the first electrode <NUM> includes a first oxide layer 811a, a metal layer 811b, and a second oxide layer 811c, and the second electrode <NUM> includes a first oxide layer 821a, a metal layer 821b, and a second oxide layer 821c. The OMO material may have a transmittance of <NUM>% or more and a sheet resistance of <NUM>Ω sq-<NUM> or less.

The first oxide layers 811a and 821a may include an oxide having a refractive index of about <NUM> to <NUM>, and a thickness of about <NUM> to <NUM>. As a concrete example, the first oxide layers 811a and 821a may include, but are not limited to, at least one among an indium-tin oxide (ITO), an indium-zinc oxide (IZO), an Al-doped ZnO (AZO), a Ga-doped ZnO (GZO), an indium-tin-zinc oxide (ITZO), a zinc-tin oxide (ZTO), an indium-gallium oxide (IGO), SnO<NUM>, TiO<NUM>, Nb<NUM>O<NUM>, ZnO, ZrO<NUM> and HfO<NUM>.

The metal layers 811b and 821b may have a thickness, for example, a thickness of about <NUM> to <NUM>, which is less than that of the first oxide layers 811a and 821a and the second oxide layers 811c and 821c. As a concrete example, the metal layers 811b and 821b may include an Ag or Ag alloy. Here, the Ag alloy may include, but is not limited to, a binary metal system such as Ag-Al, Ag-Mo, Ag-Au, Ag-Pd, Ag-Ti, or Ag-Cu or a ternary metal system such as Ag-Au-Pd or Ag-Au-Cu.

The second oxide layers 811c and 821c may include the same material as the first oxide layers 811a and 821a or a material having a refractive index less than that of the first oxide layers 811a and 821a. The second oxide layers 811c and 821c may include an oxide having a refractive index of about <NUM> to <NUM> and a thickness of about <NUM> to <NUM>. As a concrete example, the second oxide layers 811c and 821c may include, but are not limited to, at least one material from among an indium-tin oxide (ITO), an indium-zinc oxide (IZO), an Al-doped ZnO (AZO), a Ga-doped ZnO (GZO), an indium-tin-zinc oxide (ITZO), a zinc-tin oxide (ZTO), an indium-gallium oxide (IGO), SnO<NUM> and ZnO.

Referring to <FIG>, the first filling layer <NUM> provided among the first electrodes <NUM> includes a material having a transmittance similar to that of the first electrodes <NUM> to prevent the visibility of the first electrode pattern. In detail, the first filling layer <NUM> includes a material having a transmittance that is different from that of the first electrodes <NUM> by <NUM>% or less. The first filling layer <NUM> may include an insulating material having a refractive index of about <NUM> to <NUM>. As a concrete example, the first filling layer <NUM> may include an inorganic oxide such as MgO, Ta<NUM>O<NUM>, SiON, or SiO<NUM> or an organic insulating material. Similar to the first filling layer <NUM>, the second filling layer provided among the second electrodes <NUM> may include a material having similar transmittance to that of the second electrodes <NUM> to prevent the visibility of the second electrode pattern. The second filling layer may include the same material as the first filling layer <NUM>.

The first electrodes <NUM> and the second electrodes <NUM> may intersect each other at a certain angle, e.g., at a right angle, while having the dielectric layer <NUM> therebetween.

<FIG> is a plan view of electrode patterns of a sensor part such as that of <FIG>. Referring to <FIG>, the electrode patterns may include a first electrode pattern and a second electrode pattern arranged to intersect each other with the dielectric layer <NUM> of <FIG> therebetween. The first electrode pattern may include first electrodes <NUM> arranged regularly in a first direction (vertically, in <FIG>) at a second pitch P2. Here, the first electrodes <NUM> may be, for example, in the form of a plurality of diamonds connected to each other. However, the first electrodes <NUM> are not limited thereto and may be in any of various other forms. The second electrode pattern may include a second electrodes <NUM> arranged regularly in a second direction (horizontally, in <FIG>) perpendicular to the first direction at the second pitch P2. Here, similar to the first electrodes <NUM>, the second electrodes <NUM> may be, for example, in the form of a plurality of diamonds connected to each other but are not limited thereto.

<FIG> is a plan view of another example of a sensor part applicable to the sensor of <FIG>. <FIG> is an enlarged view of a part of the sensor part of <FIG>.

Referring to <FIG> and <FIG>, a first electrode pattern and a second electrode pattern are provided on a same plane, unlike in the sensor part <NUM> of <FIG>. In detail, the first electrode pattern may include first electrodes <NUM>' arranged regularly at a second pitch P2 in a first direction (vertically, in <FIG>). Here, the first electrodes <NUM>' may be, for example, in a form of a plurality of diamonds connected to each other but are not limited thereto.

The second electrode pattern may be provided on the same plane as the first electrode pattern. The second electrode pattern may include second electrodes <NUM>' arranged regularly at the second pitch P2 in a second direction (horizontally, in <FIG>) perpendicular to the first direction. Here, similar to the first electrodes <NUM>', the second electrodes <NUM>' may be in a form of a plurality of diamonds connected to each other but are not limited thereto.

In the present example embodiment, as shown in <FIG>, a dielectric layer <NUM>' may be provided at intersections of the first electrode pattern and the second electrode pattern provided on the same plane. That is, the dielectric layer <NUM>' may be provided between pairs of adjacent ones of the first electrodes <NUM>' and the second electrodes <NUM>' at the intersections of the first electrode pattern and the second electrode pattern.

<FIG> illustrates a pixel pattern of a display panel and electrode patterns of a sensor of a display apparatus such as that of <FIG>. In <FIG>, a transparent protective layer which protects a sensor part <NUM> is not illustrated for convenience of explanation.

Referring to <FIG>, a display apparatus <NUM> includes a display panel <NUM> including a pixel pattern <NUM>, and the sensor <NUM> of <FIG> provided on the display panel <NUM> and including the electrode patterns.

The display panel <NUM> may include, for example, an organic light-emitting display panel or a liquid crystal display panel which displays color images. The display panel <NUM> includes the pixel pattern <NUM> in which a plurality of pixels PX are arranged regularly at a first pitch P1. In the display apparatus <NUM> which is a high-resolution display apparatus, the first pitch P1 of the pixel pattern <NUM> is <NUM> or less.

The sensor <NUM> includes a fingerprint sensor or a fingerprint-touch composite sensor. The sensor <NUM> may include a sensor part <NUM> provided on a transparent substrate <NUM>. The sensor part <NUM> may include electrode patterns having a first electrode pattern and a second electrode pattern. For convenience of illustration, the protective layer <NUM> is not illustrated in <FIG>.

In detail, the sensor part <NUM> may include a dielectric layer <NUM>, a first electrode layer <NUM> provided on a bottom surface of the dielectric layer <NUM>, and a second electrode layer <NUM> provided on a top surface of the dielectric layer <NUM>. Here, the first electrode layer <NUM> may include a first electrode pattern with a plurality of first electrodes <NUM> arranged regularly at a second pitch P2, and a first filling layer <NUM> provided to fill gaps among the first electrodes <NUM>, disposed between adjacent ones thereof. Here, the first filling layer <NUM> may be formed among the first electrodes <NUM> and at a same height as or at a lower height than that the first electrodes <NUM>. The second electrode layer <NUM> may include a second electrode pattern with a plurality of second electrode <NUM> arranged regularly, at a second pitch P2, and in a direction intersecting a direction in which the first electrodes <NUM> are arranged, and a second filling layer (not shown) provided to fill gaps among the second electrodes <NUM>, disposed between adjacent ones thereof. The second filling layer may be formed among second electrodes <NUM> and at the same height as the second electrodes <NUM> or at a lower height than that of the second electrodes <NUM>.

The first pitch P1 of the pixel pattern <NUM> and the second pitch P2 of the electrode patterns are values at which the moiré pattern occurring due to the overlapping of the electrode patterns and the pixel pattern <NUM> becomes visible when the first and second filling layers <NUM> and <NUM> are not provided. In the display apparatus <NUM> which is a high-resolution display apparatus, when the first pitch P1 of the pixel pattern <NUM> is <NUM> or less, the second pitch P2 of the electrode pattern is <NUM> or less.

The first filling layer <NUM> and the second filling layer prevent the visibility of the moiré pattern which occurs due to the overlapping of the pixel pattern <NUM> and the electrode patterns. To this end, the first filling layer <NUM> and the second filling layer include a material having similar transmittances to those of the first and second electrodes <NUM> and <NUM>, respectively, as described above. The first filling layer <NUM> and the second filling layer include a material having a transmittance that is different from that of the first and second electrodes <NUM> and <NUM>, respectively, by <NUM>% or less.

The visibility of the first electrode pattern may be prevented due to the first filling layer <NUM>, and the visibility of the second electrode pattern may be prevented due to the second filling layer. That is, the electrode patterns of the sensor part <NUM> may not be visible due to the first filling layer <NUM> and the second filling layer. Thus, since the electrode patterns are not visible due to the first filling layer <NUM> and the second filling layer, the moiré pattern may not be visible even when the electrode patterns overlap the pixel pattern <NUM>. As described above, the visibility of the moiré pattern which may occur due to the overlapping of the pixel pattern <NUM> and the electrode patterns is prevented using the first filling layer <NUM> and the second filling layer.

Although a case in which the first and second electrode patterns are provided below and on the dielectric layer <NUM> has been described above, the first and second electrode patterns may be provided on a same plane as illustrated in <FIG>. In this case, a filling layer (not shown) may be provided among the first electrodes <NUM>' and among the second electrodes <NUM>' to prevent the visibility of the electrode patterns.

<FIG> illustrates a display apparatus according to another example embodiment. A display apparatus <NUM>' illustrated in <FIG> is the same as the display apparatus <NUM> of <FIG> except that first and second filling layers <NUM>' and <NUM>' cover first and second electrodes <NUM> and <NUM>, respectively.

Referring to <FIG>, the display apparatus <NUM>' includes a display panel <NUM> including a pixel pattern <NUM>, and the sensor <NUM> of <FIG> provided on the display panel <NUM> and including electrode patterns. For convenience of illustration, the protective layer <NUM> is not illustrated in <FIG>.

The display panel <NUM> includes the pixel pattern <NUM> with a plurality of pixels PX arranged regularly at a first pitch P1. A sensor part <NUM>' of the sensor <NUM> may include first and second electrode patterns. In detail, the sensor part <NUM>' may include a dielectric layer <NUM>', a first electrode layer <NUM>' provided on a bottom surface of the dielectric layer <NUM>', and a second electrode layer <NUM>' provided on a top surface of the dielectric layer <NUM>'. The first electrode layer <NUM>' may include a first electrode pattern with the first electrodes <NUM> arranged regularly at a second pitch P2, and a first filling layer <NUM>' provided to fill gaps among the first electrodes <NUM>, filling spaces between adjacent ones thereof. Here, the first filling layer <NUM>' may cover the first electrodes <NUM>. That is, the first filling layer <NUM>' may be formed to a higher height than that of the first electrodes <NUM>. The second electrode layer <NUM>' may include a second electrode pattern with the second electrodes <NUM> arranged regularly at the second pitch P2 to intersect the first electrodes <NUM>, and a second filling layer <NUM>' provided to fill gaps among the second electrodes <NUM>, filling spaces between adjacent ones thereof. Here, the second filling layer <NUM>' may cover the second electrodes <NUM>. That is, the second filling layer <NUM>' may be formed to a higher height than that of the second electrodes <NUM>.

As described above, the first and second filling layers <NUM>' and <NUM>' include a material having a transmittance that is different from that of the first and second electrodes <NUM> and <NUM>, respectively, by <NUM>% or less. Thus, the electrode patterns may not be visible due to the first and second filling layers <NUM>' and <NUM>' and the moiré pattern occurring due to the overlapping of the electrode patterns and the pixel pattern <NUM> is be visible.

Although a case in which the first and second electrode patterns are provided below and on the dielectric layer <NUM>' has been described above, the first and second electrode patterns may be provided on the same plane as illustrated in <FIG>. In this case, a filling layer (not shown) may be provided to cover the first electrodes <NUM> second electrodes <NUM> so as to prevent the visibility of the electrode patterns.

<FIG> illustrates a display apparatus according to another example embodiment.

Referring to <FIG>, a display apparatus <NUM> includes a display panel <NUM>, a first sensor <NUM> provided on the display panel <NUM>, and may include a second sensor <NUM> provided between the display panel <NUM> and the first sensor <NUM>.

The display panel <NUM> may include, for example, an organic light-emitting display panel or a liquid crystal display panel which display color images. The display panel <NUM> includes a pixel pattern having a first pitch. The display panel <NUM> is as described above and is thus not described in detail here.

The first sensor <NUM> may be, for example, a fingerprint sensor. The first sensor <NUM> includes electrode patterns having a second pitch, and a filling layer provided among electrodes to prevent the electrode patterns from being visible. The first sensor <NUM> is the same as the sensors described above and is thus not described in detail here.

The second sensor <NUM> may be, for example, a touch sensor. The second sensor <NUM> includes a touch electrode pattern (not shown) having a certain pitch. The second sensor <NUM> has the same structure as the first sensor <NUM> but the touch electrode pattern of the second sensor <NUM> may have a pitch that is large enough to prevent the moiré pattern from being visible when the pixel pattern of the display panel <NUM> and the electrode patterns of the first sensor <NUM> overlap each other. For example, in the display apparatus <NUM> which is a high-resolution display apparatus, the pixel pattern of the display panel <NUM> has a pitch of <NUM> or less and the electrode patterns of the first sensor <NUM> which is a fingerprint sensor has a pitch of <NUM> (more particularly, <NUM>) or less. The touch electrode pattern of the second sensor <NUM> which is a touch sensor may have a comparatively large pitch of about <NUM> or more.

In the display apparatus <NUM> as described above, the moiré pattern is not visible due to the comparatively large pitch of the second sensor <NUM> which is a touch sensor even when the second sensor <NUM> overlaps the display panel <NUM> or the first sensor <NUM>. Furthermore, the first sensor <NUM> includes the filling layer for preventing the visibility of the electrode patterns as described above and thus the visibility of the moiré pattern may be prevented even when the first sensor <NUM> overlaps the display panel <NUM> or the second sensor <NUM>.

In a high-resolution display apparatus, the moiré pattern is visible when a pixel pattern of a display panel and electrode patterns of a fingerprint sensor (or a fingerprint-touch composite sensor) overlap each other. In this case, the visibility of the moiré pattern due to the overlapping of the pixel pattern and the electrode patterns may be prevented by providing a filling layer having similar transmittance to those of electrodes of the electrode patterns among the electrodes, between adjacent ones thereof.

According to the one or more of the above example embodiments, when a first element pattern with first elements arranged regularly at a first pitch and a second element pattern with second elements arranged regularly at a second pitch overlap each other, a filling layer having similar transmittance to those of the first elements is provided among the first elements, between adjacent ones thereof, or a filling layer having similar transmittance to those of the second elements is provided among the second elements, between adjacent ones thereof. Thus, the visibility of the moiré pattern which may occur due to the overlapping of the first element pattern and the second element pattern may be prevented.

In a high-resolution display apparatus, the moiré pattern is visible when a pixel pattern of a display panel and electrode patterns of a fingerprint sensor (or a fingerprint-touch composite sensor) overlap each other. In this case, a filing layer having a transmittance similar to that of electrodes of the electrode patterns may be provided on the electrodes to prevent the visibility of the moiré pattern which may occur due to the overlapping of the pixel pattern and the electrode patterns.

It should be understood that example embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other example embodiments.

Claim 1:
A display apparatus (<NUM>, <NUM>', <NUM>) comprising:
a display panel (<NUM>, <NUM>) comprising a pixel pattern (<NUM>, <NUM>') comprising a plurality of pixels (PX) arranged regularly at a first pitch (P1); and
a first sensor (<NUM>, <NUM>) provided on the display panel,
wherein the first sensor comprises:
an electrode pattern comprising a plurality of electrodes (<NUM>, <NUM>) arranged regularly at a second pitch (P2); and
a filling layer (<NUM>) filling gaps between adjacent ones of the plurality of electrodes,
wherein a difference between a transmittance of the plurality of electrodes and a transmittance of the filling layer is <NUM>% or less;
wherein the plurality of electrodes each comprise a first oxide layer (811a, 821a), a metal layer (811b, 821b), and a second oxide layer (811c, 821c) which are sequentially stacked;
wherein the first pitch is <NUM> or less,
the second pitch is <NUM> or less, and
wherein the first sensor is one of a fingerprint sensor and a fingerprint-touch composite sensor.