TWI385455B - Transflective pixel structure and display pane - Google Patents

Description

Semi-transflective pixel structure and display panel

The present invention relates to a pixel structure and a display panel having the pixel structure, and more particularly to a transflective pixel structure and a display panel having the transflective pixel structure.

Today's social multimedia technology is quite developed, and most of them benefit from the advancement of semiconductor components or display devices. As far as the display is concerned, a liquid crystal display having superior characteristics such as high image quality, good space utilization efficiency, low power consumption, and no radiation has gradually become the mainstream of the market. Generally, liquid crystal displays can be classified into three types: transmissive, reflective, and transflective. The transflective liquid crystal display can be used in both light and low light, so it can be applied in a wide range.

In the case of a transflective liquid crystal display, it can simultaneously display using a backlight and an external light source. In general, a transflective liquid crystal display includes a pixel array substrate, a counter substrate, and a liquid crystal layer interposed between the two substrates. The pixel structure on the pixel array substrate has a penetrating region and a reflecting region, and a transparent pixel electrode is disposed in the penetrating region, and a reflective pixel electrode is disposed in the reflecting region.

In general, in order to simultaneously take into account the reflectance of the reflective pixel electrode and the transmittance of the transparent pixel electrode, the thickness of the reflective pixel electrode is often significantly larger than the thickness of the transparent pixel electrode. Therefore, there is a height difference at the boundary between the reflective region and the penetrating region, that is, at the boundary between the reflective pixel electrode and the transparent pixel electrode. Even if a layer of alignment material is subsequently applied over the reflective pixel electrode and the transparent pixel electrode, this height difference still exists. Due to the existence of this height difference, when the alignment material layer is subjected to the rubbing alignment treatment, the peeling of the reflective pixel electrode tends to occur at this height difference. This is because when the roller is used for the rubbing alignment treatment of the alignment material layer, when the roller rolls from the penetration region to the higher reflection region, the roller forms an upward difference between the reflection region and the penetration region. Stress. When the upward stress is greater than the adhesion between the reflective pixel electrode and the underlying film layer, the phenomenon that the reflective pixel electrode is peeled off occurs.

Therefore, the present invention provides a transflective pixel structure and a display panel having the transflective pixel structure to solve the conventional alignment process of the transflective pixel structure. The case where the reflective pixel electrode is peeled off.

The present invention provides a transflective pixel structure comprising a substrate, an active device, a cover layer, a reflective pixel electrode, a transparent pixel electrode, at least one transparent pattern, and an alignment layer. The substrate has a reflective area and a transmissive area. The active component is located on the substrate. The cover layer is on the substrate and covers the active component, wherein the cover layer has a plurality of raised structures in the reflective region. The reflective pixel electrode is disposed on the cover layer of the reflective area and electrically connected to the active component. The transparent pixel electrode is located on the cover layer of the penetration region and is electrically connected to the active device. The transparent pattern covers at least one corner of the reflective pixel electrode. The alignment layer covers the reflective pixel electrode, the transparent pixel electrode, and the transparent pattern, wherein the alignment layer has an alignment direction, the diagonal of the reflective pixel electrode follows the alignment direction, and the at least one transparent pattern is located at a corner on the diagonal line .

The invention provides a display panel comprising a pixel array substrate, the pixel array substrate having a plurality of pixel structures, wherein each pixel structure is a transflective pixel structure as described above; a substrate, located opposite the pixel array substrate; and a liquid crystal layer between the pixel array substrate and the opposite substrate.

Since the present invention is provided with a transparent pattern at at least one corner of the reflective pixel electrode, and the transparent pattern is located at a corner of the diagonal of the reflective pixel electrode, wherein the diagonal line is along the alignment direction of the alignment layer . Therefore, when the alignment treatment is performed on the transflective pixel structure, peeling of the edge of the reflective pixel electrode can be avoided.

The above described features and advantages of the present invention will be more apparent from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a top plan view showing a transflective pixel structure according to an embodiment of the present invention, and Fig. 2 is a schematic view taken along line I-I'. Referring to FIG. 1 and FIG. 2 simultaneously, the transflective pixel structure of the embodiment includes a substrate 100, an active device 120, a cover layer 104, a reflective pixel electrode 106, a transparent pixel electrode 108, and at least one transparent pattern. 109 and an alignment layer 110.

The substrate 100 has a reflective area R and a transmissive area T. The substrate 100 can be a glass substrate, a plastic substrate, a germanium substrate, or other suitable substrate. The substrate 100 includes a scan line SL, a data line DL, and an active device 120. In this embodiment, the active device 120 is electrically connected to the scan line SL and the data line DL. The active component 120 is, for example, a thin film transistor that includes a gate, a source, and a drain. In general, since the active component 120 is a light blocking component, the active component 120 is preferably disposed in the reflective region R. However, the invention does not limit the position at which the active components are placed. In other embodiments, the active component 120 may also be disposed in the penetration region T according to design requirements, or may simultaneously span the reflective region R and the penetration region T.

In addition, due to the manufacturing process of the active device 120, the surface of the substrate 100 is generally covered with an insulating layer 102 after the manufacturing process of the active device 120 is completed. This insulating layer 102 is, for example, a laminate of a gate insulating layer and a protective layer. However, the present invention is not limited thereto. In other embodiments, the substrate 100 may not be covered with the insulating layer 102, or the insulating layer 102 itself may be a single film layer, or the insulating layer 102 may be a layer of three or more layers. .

The cover layer 104 is located on the substrate 100 and covers the active device 120, the scan line SL, the data line DL, and the insulating layer 102. In other words, the cover layer 104 covers the entire substrate 100. The material of the cover layer 104 is preferably selected from organic materials having photosensitive properties. In particular, the cover layer 104 has a plurality of raised structures 106 in the reflective region R. The purpose of providing the raised structure 106 in the reflective region R is to increase the reflectivity of the reflective region R of the pixel structure. The raised structure 106 can be formed by means of lithography. It is particularly worth mentioning that the present invention does not limit the material of the cover layer 104, the formation manner, shape, density and position of the raised structure 106. The raised structure 106 illustrated in the drawings of the present embodiment is for clarity only.

In addition, the reflective pixel electrode 106 is disposed on the cover layer 104 of the reflective region R, so that the reflective pixel electrode 106 covers the raised structure 104a. In addition, the reflective pixel electrode 106 is electrically connected to the active device 120. In the present embodiment, the reflective pixel electrode 106 is electrically connected to one end of the active device 120 (for example, the drain of the thin film transistor) through the contact opening H. The material of the reflective pixel electrode 106 is, for example, a metal, and a metal material having high reflectance and high conductivity is preferably used. It is worth mentioning that in the present embodiment, the area occupied by the reflective pixel electrode 106 in the reflective region R is larger than the area occupied by the convex structure 104a of the cover layer 104 in the reflective region R.

The transparent pixel electrode 108 is on the cover layer 104 of the penetration region T. In particular, both the transparent pixel electrode 108 and the reflective pixel electrode 106 are connected together. Since the reflective pixel electrode 106 is electrically connected to the active device 120, and the reflective pixel electrode 106 is connected to the transparent pixel electrode 108, the transparent pixel electrode 108 is also electrically connected to the active device 120. As a result, when the pixel structure is operated, the transparent pixel electrode 108 and the reflective pixel electrode 106 are in a common potential state. Further, the material of the transparent pixel electrode 108 is, for example, a transparent conductive material such as a metal oxide such as indium tin oxide, indium zinc oxide or other metal oxide.

In addition, the transparent pattern 109 is covered at at least one corner C of the reflective pixel electrode 106. In the embodiment of FIG. 1, the transparent pattern 109 is disposed at four corners C of the reflective pixel electrode 106. Here, the transparent pattern 109 is directly attached to at least one corner C of the reflective pixel electrode 106, and the transparent pattern 109 may be fabricated together when the transparent pixel electrode 108 is formed. In other words, the transparent pattern 109 and the transparent pixel electrode 108 can be defined by the same mask. However, the present invention is not limited thereto, and in other embodiments, the transparent pattern 109 and the transparent pixel electrode 108 may be separately fabricated. Therefore, the material of the transparent pattern 109 may be the same as or different from the material of the transparent pixel electrode 108. The material of the transparent pattern 109 is, for example, a transparent conductive material such as a metal oxide such as indium tin oxide, indium zinc oxide or other metal oxide. In addition, the transparent pattern 109 of the present embodiment is a block pattern, which may be square, rectangular, circular or polygonal. Further, the transparent pattern 109 of the present invention may extend about 0 to 30 microns across the edge of the reflective pixel electrode 106, and the transparent pattern 109 overlaps the reflective pixel electrode 106 by a width of about 0 to 30 microns. Since the transparent pattern 109 of the present embodiment will straddle the edge of the reflective pixel electrode 106, the distance of the transparent pattern 109 from the edge of the reflective pixel electrode 106 is not zero.

The alignment layer 110 covers the reflective pixel electrode 106, the transparent pixel electrode 108, and the transparent pattern 109. In other words, the alignment layer 110 covers the entire film layer on the substrate 100. In particular, the alignment layer 110 has an alignment direction D, and a pair of angular lines L of the reflective pixel electrodes 106 follow the alignment direction D. Preferably, the diagonal L of the reflective pixel electrode 106 is parallel to the alignment direction D, and the transparent pattern 109 is located at a corner C on the diagonal L of the reflective pixel electrode 106. In other words, the transparent pattern 109 is located at least at a corner C on the diagonal L of the reflective pixel electrode 106. Therefore, in another embodiment of the present invention, the transparent pattern 109 may not be provided at the other two corners of the reflective pixel electrode 106 (the corners not falling on the diagonal line L), as shown in FIG.

Since the present invention covers the corner C on the diagonal L of the reflective pixel electrode 106 with the transparent pattern 109, the reflection can be avoided when the roller rubbing alignment process is subsequently performed on the transflective pixel structure. The pixel electrode 108 is peeled off.

In addition to the embodiment shown in FIG. 1, in which a transparent pattern 109 is disposed at a corner C of the reflective pixel electrode 106, a transparent pattern 109a may be disposed on a partial edge of the reflective pixel electrode 106, as shown in FIG. Show.

In addition, the transparent pattern 109 in the pixel structure shown in FIGS. 1, 3, and 4 is a discontinuous block pattern. However, the present invention is not limited thereto, and in other embodiments, the transparent pattern 109 may also be a continuous strip pattern as described below.

Referring first to FIG. 5, the pixel structure of FIG. 5 is similar to the pixel structure shown in FIG. 1, except that the transparent pattern 109 is a strip pattern covering the opposite edges of the reflective pixel electrode 106, respectively. At the office. Similarly, in this embodiment, the transparent pattern 109 is produced together when the transparent pixel electrode 108 is fabricated. However, the present invention is not limited thereto, and in other embodiments, the transparent pattern 109 and the transparent pixel electrode 108 may be separately fabricated. Therefore, the materials of the transparent pixel electrode 108 and the transparent pattern 109 may be the same or different.

In addition, referring to FIG. 6, the pixel structure of FIG. 6 is similar to the pixel structure shown in FIG. 5, except that the strip transparent pattern 109 covers the other two opposite edges of the reflective pixel electrode 106. .

In the embodiment of FIGS. 5 and 6, the transparent pattern 109 covers all corners of the reflective pixel electrode 106 and the opposite edges of the reflective pixel electrode 109. However, in other embodiments, the transparent pattern 109 may also cover only one of the edges of the reflective pixel electrode 106, as shown in FIG. In the pixel structure of FIG. 7, the transparent pattern 109 covers only one of the edges of the reflective pixel electrode 106, and the edge is the one that the alignment roller first contacts the reflective pixel electrode 106 when the alignment process is subsequently performed. edge.

In the above-described embodiments of FIGS. 5 to 7, the transparent pattern 109 covers the edges of the reflective pixel electrode 106, and also covers the corners at both ends of the edge, and the transparent pattern 109 extends over the edge of the reflective pixel electrode 106. The distance spanned may be 0 to 30 micrometers, and the width of the transparent pattern 109 and the reflective pixel electrode 106 may be 0 to 30 micrometers. Similarly, since the transparent pattern 109 of the embodiment of FIGS. 5 to 7 will straddle the edge of the reflective pixel electrode 106, the distance of the transparent pattern 109 from the edge of the reflective pixel electrode 106 is not zero.

According to other embodiments, the transparent pattern 109 may not completely extend beyond the corners of the reflective pixel electrode 106, as in the embodiment of FIG. In other words, the transparent pattern 109 spans the E1 edge of the reflective pixel electrode 106 but does not span the other edge E2 of the reflective pixel electrode 106. In the embodiment of FIG. 9, the transparent pattern 109 spans the edge E2 of the reflective pixel electrode 106 but does not span the other edge E1 of the reflective pixel electrode 106. In the above embodiments of FIG. 8 and FIG. 9, the distance that the transparent pattern 109 spans the reflective pixel electrode 106 may be 0 to 30 micrometers. Likewise, the transparent pattern 109 may overlap the reflective pixel electrode 106 by a width of 0 to 30 microns.

Similarly, the transparent pattern 109 of the embodiment of FIG. 8 and FIG. 9 may also cover only one of the edges of the reflective pixel electrode 106 (eg, only one of the edges E1 or one of the edges E2), and this edge is followed. When the alignment process is performed, the alignment roller first contacts the edge of the reflective pixel electrode 106.

FIG. 10 is a cross-sectional view of a display panel in accordance with an embodiment of the present invention. Referring to FIG. 10 , the display panel includes a pixel array substrate 202 , a counter substrate 204 , and a liquid crystal layer 206 . The pixel array substrate 202 has a plurality of pixel structures, and each of the pixel structures may be a transflective pixel structure as shown in any of FIGS. 1 and 3 to 8. The opposite substrate 204 is located opposite to the pixel array substrate 202, and the opposite substrate 204 may be a blank substrate or a substrate provided with an electrode film. The liquid crystal layer 206 is located between the pixel array substrate 202 and the opposite substrate 204. In addition, the display panel may further include a color filter layer, which may be disposed on the pixel array substrate 202 or the opposite substrate 204. If the color filter layer is disposed on the pixel array substrate 202, the pixel array substrate 202 may be referred to as a color filter on array (COA).

In summary, since the present invention is provided with a transparent pattern at at least one corner of the reflective pixel electrode, and the transparent pattern is located at a corner of the diagonal of the reflective pixel electrode, wherein the diagonal line is followed The alignment direction of the alignment layer. Therefore, when the alignment treatment is performed on the transflective pixel structure, peeling of the edge of the reflective pixel electrode can be avoided.

Further, since the transparent pattern of the present invention does not cover the entire edge of the reflective pixel electrode, it is possible to reduce the situation in which the reflectance of the reflective pixel electrode is lowered by the presence of the transparent pattern.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100. . . Substrate

102. . . Insulation

104. . . Cover layer

104a. . . Raised pattern

106. . . Reflective pixel electrode

108. . . Transparent pixel electrode

109,109a. . . Transparent pattern

110. . . Alignment layer

120. . . Active component

202. . . Pixel array substrate

204. . . Counter substrate

206. . . Liquid crystal layer

R. . . Reflection zone

T. . . Penetration zone

SL. . . Scanning line

DL. . . Data line

H. . . Contact window opening

D. . . Orientation direction

L. . . diagonal

C. . . corner

E1, E2. . . edge

1 is a top plan view of a transflective pixel structure in accordance with an embodiment of the present invention.

Figure 2 is a schematic cross-sectional view of the view 1 taken along line I-I'.

3 through 9 are top plan views of a transflective pixel structure in accordance with various embodiments of the present invention.

FIG. 10 is a cross-sectional view of a display panel in accordance with an embodiment of the present invention.

106. . . Reflective pixel electrode

108. . . Transparent pixel electrode

109. . . Transparent pattern

110. . . Alignment layer

120. . . Active component

R. . . Reflection zone

T. . . Penetration zone

SL. . . Scanning line

DL. . . Data line

H. . . Contact window opening

D. . . Orientation direction

L. . . diagonal

C. . . corner

Claims (13)

A transflective pixel structure comprising: a substrate having a reflective area and a transmissive area; an active component on the substrate; a cover layer on the substrate covering the active component, Wherein the cover layer has a plurality of convex structures in the reflective region; a reflective pixel electrode disposed on the cover layer of the reflective region and electrically connected to the active device; a transparent pixel electrode located at the through hole The cover layer of the through region is electrically connected to the active device; at least one transparent pattern covering at least one corner of the reflective pixel electrode; and an alignment layer covering the reflective pixel electrode and the transparent pixel electrode And the transparent pattern, wherein the alignment layer has an alignment direction, a pair of diagonal lines of the reflective pixel electrode follow the alignment direction, and the at least one transparent pattern is located at a corner of the diagonal line. The transflective pixel structure of claim 1, wherein the at least one transparent pattern covers all corners of the reflective pixel electrode. The transflective pixel structure of claim 1, wherein the at least one transparent pattern further comprises a partial edge covering the reflective pixel electrode. The transflective pixel structure of claim 1, wherein the transparent patterns are non-continuous patterns. A transflective pixel as described in claim 1 The structure, wherein the at least one transparent pattern further comprises covering one of the edges of the reflective pixel electrode. The transflective pixel structure of claim 1, wherein the at least one transparent pattern further comprises opposite edges covering the reflective pixel electrodes. The transflective pixel structure of claim 1, wherein the at least one transparent pattern covers all corners of the reflective pixel electrode and opposite edges of the reflective pixel electrode. The transflective pixel structure of claim 1, wherein the at least one transparent pattern extends from the edge of the reflective pixel electrode by 0 to 30 micrometers, and the at least one transparent pattern and the reflective image The electrode overlap width is 0 to 30 microns. The transflective pixel structure of claim 1, wherein the at least one transparent pattern is a block, a strip, or a combination thereof. The transflective pixel structure of claim 1, wherein the material of the at least one transparent pattern is the same as the material of the transparent pixel electrode. The transflective pixel structure of claim 1, wherein the area of the reflective pixel in the reflective area is larger than the convex structure of the cover layer in the reflective area. Area. The transflective pixel structure of claim 1, wherein the reflective pixel electrode is sandwiched between the transparent pattern and the cover layer. A display panel includes: a pixel array substrate having a plurality of pixel structures, and each pixel The structure is as described in claim 1 of the patent application; a pair of substrates located opposite to the pixel array substrate; and a liquid crystal layer between the pixel array substrate and the opposite substrate.