CN101477268B - Semi-penetration semi-reflection type display panel - Google Patents

Abstract

The invention relates to a semi-penetrative semi-reflecting type display panel. The display panel comprises a first substrate, a plurality of electroluminescent elements arranged on the first substrate, a plurality of reflecting bodies arranged on the first substrate, a second substrate in opposite arrangement with the first substrate, a plurality of transparent electrodes arranged on one side of the second substrate facing the first substrate, a plurality of color filter layers arranged on one side of the second substrate facing the first substrate and a liquid crystal layer arranged between the first substrate and the second substrate. Therefore, the semi-penetrative semi-reflecting type display panel can improve insufficient contrast ratio produced when the brightness of the ambient light is overlarge.

Description

transflective display panel

technical field

The invention relates to a semi-transmitting and semi-reflecting display panel, in particular to a display panel having an electroluminescent display panel and a semi-transmitting and semi-reflecting liquid crystal display panel.

Background technique

In recent years, electroluminescent display panels, such as organic electroluminescent display panels, can be made into flexible panels due to their self-illumination, wide viewing angle, fast response time, high luminous efficiency, low operating voltage, and thin panel thickness. As well as the advantages of simple process, etc., it has gradually become a popular emerging flat-panel display, and is widely used in various flat-panel display products.

Please refer to FIG. 1 , which is a schematic cross-sectional view of a conventional electroluminescence display panel. As shown in FIG. 1 , a known electroluminescent display panel 10 includes a thin film transistor substrate 12 , an anode 14 , an organic light emitting layer 16 , a cathode 18 and a transparent substrate 20 . Wherein, the TFT substrate 12 includes a substrate 22 , a TFT 24 disposed on the substrate 22 , and a protection layer 26 covering the TFT 24 and the substrate 22 . The anode 14 covers the passivation layer 26 and is electrically connected to the drain of the thin film transistor 24 through the contact hole 28 . In addition, the organic light emitting layer 16 is disposed on the anode 14 , the cathode 18 is disposed on the organic light emitting layer 16 , and the transparent substrate 20 covers the cathode 18 .

It is known that the display brightness of the electroluminescent display panel is determined by the light output brightness of the organic light-emitting layer. When the brightness of the ambient light is greater, the ratio of the brightness of the light emitted by the organic light-emitting layer to the brightness of the ambient light will be relatively reduced, so that the known The contrast of the picture displayed by the electroluminescent display panel is reduced, so that the displayed picture cannot be viewed. In the conventional organic light-emitting display panel, improving the contrast reduction can only increase the light-emitting brightness of the organic light-emitting layer, so as to prevent the display screen of the electroluminescent display from being affected by excessively high ambient light brightness. However, increasing the luminance of the organic light-emitting layer not only consumes power, but also shortens the service life of the organic light-emitting layer. Therefore, improving the contrast of the electroluminescent display panel when the ambient light brightness is too high is an important issue.

Contents of the invention

One of the objectives of the present invention is to provide a transflective display panel to solve the problem of insufficient contrast in the conventional electroluminescence display when the brightness of the ambient light is too high.

To achieve the above object, the present invention provides a transflective display panel. A plurality of pixel areas are defined on the transflective display panel, and each pixel area includes a reflection area and a transmission area. The transflective display panel includes a first substrate, a plurality of driving elements arranged on the first substrate, a plurality of electroluminescent elements arranged on the first substrate, and a plurality of reflectors arranged on the first substrate , a second substrate arranged opposite to the first substrate, a plurality of first switching elements arranged on the side of the second substrate facing the first substrate, a plurality of transparent electrodes arranged on the side of the second substrate facing the first substrate , a plurality of color filter layers disposed on the side of the second substrate facing the first substrate, and a liquid crystal layer disposed between the first substrate and the second substrate. Each driving element is respectively located in each pixel area. Each electroluminescent element is respectively located in each penetrating area, and in the same pixel area, the electroluminescent element is electrically connected with the driving element. Each reflector is respectively arranged in each reflection region, and each first switch element is respectively arranged in each pixel region. In the same pixel area, each transparent electrode is respectively located in the transmissive area and extends to the reflective area to be electrically connected with the first switch element. Each color filter layer is respectively arranged in each pixel area.

In the present invention, an electroluminescent element is formed on the first substrate in the transmissive area, and a reflector is provided on the first substrate in the reflective area and a color filter layer is provided on the second substrate in the pixel area, so as to be used in the electroluminescence. A semi-transmissive and semi-reflective liquid crystal display panel is formed above the exciting light element. Therefore, this embodiment not only has an electroluminescent element display screen, but also has a transflective liquid crystal display panel that can use the brightness of ambient light to enhance the display brightness of the transflective display panel, so as to effectively improve the conventional electroluminescence. The excitation light display panel has a problem of insufficient contrast when the brightness of the ambient light is too high.

Description of drawings

In order to make the above and other objects, features, advantages and embodiments of the present invention more comprehensible, the detailed description of the accompanying drawings is as follows:

1 is a schematic cross-sectional view of a known electroluminescent display panel;

2 is an exploded schematic diagram of a transflective display panel according to a first preferred embodiment of the present invention;

3 is a schematic cross-sectional view of a transflective display panel according to a first preferred embodiment of the present invention;

4 is a schematic cross-sectional view of another embodiment of the transflective display panel of the first preferred embodiment;

FIG. 5 is a schematic cross-sectional view of a transflective display panel according to a second preferred embodiment of the present invention.

Among them, reference signs

10 Electroluminescence display panel 12 Thin film transistor substrate

14 Anode 16 Organic light-emitting layer

18 Cathode 20 Transparent Substrate

22 Substrates 24 Thin Film Transistors

26 Protection layer 28 Contact hole

100 transflective display panel 102 pixel area

102R reflective zone 102T penetrating zone

104 First Substrate 106 Second Substrate

108 Liquid crystal layer 110 Shared line

112 first switch element 114 transparent electrode

116 Color filter layer 118 Power cord

120 Second switching element 122 Driving element

124 Electroluminescent element 126 Reflector

128 Anode 130 Luminescent layer

132 Cathode 134 Storage Capacitor

136 Bumps 138 Alignment film

140 Alignment film 142 Protrusion

144 quarter wave plate 146 polarizer

Detailed ways

Please refer to FIG. 2 and FIG. 3 , FIG. 2 is an exploded schematic diagram of a transflective display panel according to a first preferred embodiment of the present invention, and FIG. 3 is a schematic diagram of a transflective display panel according to a first preferred embodiment of the present invention. A schematic cutaway of the display panel. As shown in FIG. 2 and FIG. 3 , a plurality of pixel regions 102 are defined on the transflective display panel 100 , and each pixel region 102 includes a reflective region 102R and a transmissive region 102T. The transflective display panel 100 of this embodiment includes a first substrate 104, a second substrate 106, and a liquid crystal layer 108, wherein the second substrate 106 is arranged opposite to the first substrate 104, and the liquid crystal layer 108 is arranged on the first substrate 108. Between the substrate 104 and the second substrate 106 . The first substrate 104 is a variety of substrates used to make thin film transistors, such as silicon substrates, glass substrates or plastic substrates, etc., and the second substrate 106 is a variety of transparent substrates used to make thin film transistors, such as glass substrates or plastic substrates wait.

In this embodiment, a plurality of gate lines GL _LCD , a plurality of data lines DL _LCD , a plurality of shared lines (Common Line) 110, a plurality of first switching elements 112, a plurality of transparent electrodes 114 and a plurality of color filters Layer 116 is located between second substrate 106 and liquid crystal layer 108 . The gate lines GL _LCD and the data lines DL _LCD are arranged on the side of the second substrate 106 facing the first substrate 104 and are substantially orthogonal to each other, and correspond to the border positions of adjacent pixel regions 102 . The sharing line 110 is disposed on a side of the second substrate 106 facing the first substrate 104 and substantially parallel to the gate line GL _LCD , and is electrically connected to a sharing voltage. Each first switching element 112 is disposed on the side of the second substrate 106 facing the first substrate 104 in each pixel area 102, and the gate of the first switching element 112 is electrically connected to the corresponding gate line GL _LCD , The source of the first switching element 112 is electrically connected to the corresponding data line DL _LCD . Each transparent electrode 114 is respectively disposed in the transmissive region 102T and extends to the second substrate 106 in the reflective region 102R to be electrically connected to the drain of the first switching element 112 in the same pixel region 102 . Each color filter layer 116 is respectively arranged on the side of the second substrate 106 facing the first substrate 104 in the reflective area 102R of each pixel area 102, and the color filter layer 116 includes a first color filter layer, a second color filter layer, and a second color filter layer. A filter layer and a third color filter layer, wherein the first color filter layer can be a red filter, the second color filter layer can be a green filter, and the third color filter layer can be a blue filter sheets, but not limited thereto, the first color filter layer, the second color filter layer and the third color filter layer can be replaced with each other.

In addition, the plurality of gate lines GL _EL , the plurality of data lines DL _EL , the plurality of power lines 118 , the plurality of second switching elements 120 , the plurality of driving elements 122 , the plurality of electroluminescence elements 124 and the plurality of A reflector 126 is located between the first substrate 104 and the liquid crystal layer 108 . The gate line GL _EL and the data line DL _EL are arranged on the first substrate 104 and are substantially orthogonal to each other, and correspond to the border positions of adjacent pixel regions 102 . The power line 118 is arranged on the first substrate 104, and is substantially parallel to the data line DL _EL and corresponds to the junction position of the adjacent pixel area 102, and is used to drive the electroluminescent element 124. In addition, the power line 118 can be connected to the shared line 110 is electrically connected, and the design of the transflective display panel 100 can be simpler. Each second switching element 120 is respectively disposed on the first substrate 104 in each pixel area 102, and in the same pixel area 102, the gate of the second switching element 120 is electrically connected to the corresponding gate line GL _EL , The source of the second switch element 120 is electrically connected to the corresponding data line DL _EL , so as to control whether the signal of the data line DL _EL is input or not through the second switch element 120 . Each driving element 122 is respectively disposed on the first substrate 104 in each pixel area 102, and the gate of the driving element 122 is electrically connected to the drain of the corresponding second switching element 120, and the source of the driving element 122 is connected to the drain of the corresponding second switching element 120. Corresponding power lines 118 are electrically connected. In this embodiment, the second switching element 120 and the driving element 122 are located in the pixel area 102 outside the reflective area 102R and the transmissive area 102T. For example, they may be located in the circuit area, but not limited thereto. The second switching element and the driving The device can also be located between the electroluminescent device 124 and the first substrate 104 in the reflective region 102R or in the transmissive region 102T. In addition, each electroluminescent element 124 is disposed on the first substrate 104 in the penetrating region 102T of each pixel region 102, and each electroluminescent element 124 includes an anode 128, a light emitting layer 130, and a cathode 132, wherein in each pixel region In 102, the anode 128, the light emitting layer 130 and the cathode 132 are sequentially disposed on the first substrate 104 in the penetrating region 102T, and the anode 128 is electrically connected to the drain of the driving element 122 in the same pixel region 102, however, it can According to the design requirements, the positions of the anode 128 and the cathode 132 are swapped, but not limited thereto. It should be noted that the cathode 132 in this embodiment is electrically connected to the corresponding sharing line 110 , so that the transparent electrode 114 and the cathode 132 can control the rotation of the liquid crystal molecules in the liquid crystal layer 108 therebetween. Moreover, in each pixel region 102 , a storage capacitor 134 is formed between the drain of the second switching element 120 or the gate of the driving element 122 and the power line 118 for storing the signal of the data line DL _EL . According to the above electrical connection relationship, the switch of the second switch element 120 can control whether the signal of the data line DL _EL is input or not, and the switch of the driving element 122 can control whether the power line 118 inputs current to drive the electroluminescent element 124 . The storage capacitor 134 can effectively slow down the speed of the switching driving element 122 , so that the current provided by the power line 118 has enough time to drive the electroluminescent element 124 . The electroluminescent element 124 may include a plurality of first electroluminescent elements, a plurality of second electroluminescent elements and a plurality of third electroluminescent elements, wherein the first electroluminescent element, the second electroluminescent element and the first electroluminescent element The three electroluminescent elements can be light emitting elements of a single color, for example: red light emitting element, green light emitting element and blue light emitting element, and the first electroluminescent element, the second electroluminescent element and the third electroluminescent element White can be formed to provide the transflective display panel 100 to display full-color images. It should be noted that the color of the light emitted by each electroluminescent element 124 located in the transmissive area 102T must be approximately the same as that of the color filter layer 116 in the same pixel area 102 , so that the same pixel displays the same color. Wherein, the light-emitting layer 130 may be composed of organic electroluminescent materials, and the electroluminescent elements 124 corresponding to different colors use materials that produce different colors. The anode 128 is made of a material with high reflectivity, such as aluminum, silver, gold, nickel, platinum or a combination thereof, so as to reflect the light generated by the light emitting layer 130 toward the outside. The cathode 132 is made of a material with high transmittance, such as a thin metal film, so that the light generated by the light emitting layer 130 can pass through the cathode 132 and emit to the outside.

In addition, each reflector 126 is respectively disposed on the first substrate 104 of each reflective region 102R, and the reflector 126 is made of a material with high reflectivity, such as a metal film, etc. light from the reflective display panel 100 . In this embodiment, the cathode 132 extends into the reflective region 102R and covers the reflector 126 , but the invention is not limited thereto. Please refer to FIG. 4 . FIG. 4 is a schematic cross-sectional view of another embodiment of the transflective display panel of the first preferred embodiment. As shown in FIG. 4, the cathode 132 does not extend into the reflective region 102R, but is only electrically connected to the reflector 126, and in this embodiment, the reflector 126 is made of a conductive material to serve as a control liquid crystal layer in the reflective region 102R. One of the 108 electrodes.

Please continue to refer to FIG. 3 , the transflective display panel 100 further includes a plurality of bumps 136 disposed on the first substrate 104 and respectively disposed in each reflective region 102R, wherein the bumps 136 can be made of an organic material and have The concave-convex surface, whereby the reflector 126 also has a concave-convex surface, is used to uniformly scatter ambient light, and the size of the liquid crystal gap in the reflective region 102R can be controlled by adjusting the thickness of the bump 136 .

In addition, the transflective display panel 100 of this embodiment further includes two alignment films 138 and 140, respectively disposed between the liquid crystal layer 108 and the first substrate 104 and between the liquid crystal layer 108 and the second substrate 106, It is used to align the liquid crystal molecules of the liquid crystal layer 108 . Moreover, the transflective display panel 100 further includes a plurality of protrusions 142 respectively disposed in each reflection area 102R, and each protrusion 142 is disposed between each transparent electrode 114 and the liquid crystal layer 108 and is located on the alignment film 140 The side facing the liquid crystal layer 108 . In addition, the transflective display panel 100 further includes a quarter-wave plate 144 and a polarizer 146 , wherein the quarter-wave plate 144 is disposed on the other side of the second substrate 106 facing the first substrate 104 , and the polarizer 146 is disposed on the quarter wave plate 144 .

It can be seen that, in this embodiment, the gate line GL _EL , the data line DL _EL , the power line 118 , the second switching element 120 and the driving element 122 are arranged on the first substrate 104 in the pixel area 102 , and in the pixel area 102 The electroluminescent element 124 is disposed in the penetrating region 102T to form an electroluminescent panel in the penetrating region 102T. In addition, in this embodiment, a gate line GL _LCD , a data line DL _LCD , a sharing line 110 , a first switching element 112 and a transparent electrode 114 are provided on the side of the second substrate 106 in the pixel area 102 facing the first substrate 104 , and electrically connect the sharing line 110 and the cathode 132 of the electroluminescent element 124, so that the liquid crystal layer 108 located between the first substrate 104 and the second substrate 106 can be driven to rotate, and then pass through the first substrate in the reflective region 102R The bump 136 and the reflector 126 are disposed on the 104 and the color filter layer 116 is disposed on the second substrate 106 in the reflective region 102R to form a transflective liquid crystal display panel above the electroluminescent panel. Therefore, this embodiment not only has an electroluminescent panel display screen, but also has a transflective liquid crystal display panel that can use the brightness of ambient light to enhance the display brightness of the transflective display panel 100, so as to effectively improve the known The contrast ratio of the electroluminescent display panel is insufficient when the brightness of the ambient light is too high.

The operation of the transflective display panel 100 of this embodiment will be described as follows. When the transflective display panel 100 is in the bright state, that is, when a bright picture is to be displayed, in the transmissive area 102T, the electric current The excitation light element 124 is driven to generate non-polarized light, so it can sequentially pass through the liquid crystal layer 108, the quarter-wave plate 144 and the polarizer 146, and a bright picture is displayed in the penetrating region 102T to provide Viewers watch. At the same time, in the reflective region 102R, a voltage difference is provided between the transparent electrode 114 and the cathode 132 of the electroluminescent element 124 to rotate the liquid crystal molecules in the liquid crystal layer 108 . At this time, the liquid crystal layer 108 has a characteristic of delaying light by a quarter wavelength. When the ambient light entering the reflective region 102R sequentially passes through the polarizer 146 , the quarter-wave plate 144 and the liquid crystal layer 108 , the ambient light will become linearly polarized light. Next, the light with linear polarization is reflected by the reflector 126, and the light with linear polarization will sequentially pass through the liquid crystal layer 108, the quarter wave plate 144 and the polarizer 146 to display a bright picture for viewing viewer. Therefore, in the bright state, even when the brightness of the ambient light is relatively high, the liquid crystal display panel located in the reflective region 102R in this embodiment can use the ambient light as brightness compensation during display, thus avoiding the problem of excessive brightness of the ambient light. The contrast of the transflective display panel 100 is affected. In addition, when the transflective display panel 100 is in the dark state, that is, when a dark picture is to be displayed, the electroluminescent element 124 is not driven and no light is generated, and the transparent electrode 114 and the cathode 132 of the electroluminescent element 124 There is no voltage difference provided between them, so the liquid crystal layer 108 is in an unrotated state and does not have the property of retarding light. At this time, in the transmissive region 102T and the reflective region 102R, the ambient light sequentially passes through the polarizer 146 and the quarter wave plate 144 to have right-handed/left-handed circular polarization. After being reflected by the reflector 126, the right-handed/left-handed circularly polarized light will be transformed into left-handed/right-handed circularly polarized light, so when the light passes through the quarter-wave plate 144, it cannot penetrate Polarizer 146, resulting in a dark state. Therefore, the transflective display panel 100 can also provide a good dark picture for the viewer to watch, and thus can have a good contrast ratio when viewed in a strong light environment.

In addition, the color filter layer of the transflective display panel of the present invention is not limited to be disposed in the reflective area, but can also be disposed in both the reflective area and the transmissive area. Please refer to FIG. 5 . FIG. 5 is a schematic cross-sectional view of a transflective display panel according to a second preferred embodiment of the present invention. In order to simplify the description and clearly compare the similarities and differences of the various embodiments of the present invention, the second preferred embodiment described below uses the same component symbols as the first preferred embodiment to mark the same components, and the same parts of the components are no longer described. Repeat it. As shown in FIG. 5 , compared with the first preferred embodiment, the color filter layers 202 of the transflective display panel 200 of this embodiment are respectively arranged in each reflective region 102R and each transmissive region 102T. . By disposing the color filter layer 202 in the transmissive region 102T, the light emitted by the electroluminescent element 124 will be purified by the color filter layer 202 , so that the colors displayed by the same pixel are consistent. In addition, in this embodiment, the electroluminescence element 124 can be a white light-emitting element in addition to a monochrome light-emitting element, for example: the light-emitting layer is a stack of red light-emitting layer, green light-emitting layer and blue light-emitting layer. Formed multiple light-emitting layers, etc.

To sum up, the present invention forms an electroluminescent panel on the first substrate in the transmissive area, and by arranging bumps and reflectors on the first substrate in the reflective area, and arranging bumps and reflectors on the second substrate in the pixel area. The color filter layer is electrically connected with the common line and the cathode of the electroluminescent element to form a transflective liquid crystal display panel above the electroluminescent panel. Therefore, this embodiment not only has an electroluminescent panel display screen, but also has a transflective liquid crystal display panel that can use the brightness of ambient light to enhance the display brightness of the transflective display panel, so as to effectively improve the conventional electroluminescence. The excitation light display panel has a problem of insufficient contrast when the brightness of the ambient light is too high.

Certainly, the present invention also can have other multiple embodiments, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding Changes and deformations should belong to the scope of protection of the appended claims of the present invention.

Claims (10)

1. semi-penetration semi-reflection type display panel, definition has a plurality of pixel regions on this semi-penetration semi-reflection type display panel, and respectively this pixel region comprises an echo area and a penetrating region, it is characterized in that, and this semi-penetration semi-reflection type display panel comprises:

One first substrate;

A plurality of driving elements are arranged on this first substrate, and respectively this driving element lays respectively at respectively in this pixel region;

A plurality of EL parts are arranged on this first substrate, and respectively this EL part lays respectively at respectively in this penetrating region, and in same pixel region, this EL part and this driving element electrically connect;

A plurality of reflecting bodys are arranged on this first substrate, and respectively this reflecting body is located at respectively respectively in this echo area;

One second substrate is provided with this first substrate subtend;

A plurality of first on-off elements are arranged at the side of this second real estate for this first substrate, and respectively this first on-off element is located at respectively respectively in this pixel region;

A plurality of transparency electrodes are arranged at the side of this second real estate to this first substrate, and in same pixel region, and respectively this transparency electrode lays respectively in this penetrating region and extends to this echo area and electrically connect with this first on-off element;

A plurality of chromatic filter layers are arranged at the side of this second real estate to this first substrate, and respectively this chromatic filter layer is located at respectively respectively in this pixel region; And

One liquid crystal layer is arranged between this first substrate and this second substrate.

2. semi-penetration semi-reflection type display panel according to claim 1, it is characterized in that, this semi-penetration semi-reflection type display panel comprises a plurality of projections in addition, be arranged on this first substrate, respectively this projection is located at respectively respectively in this echo area, and respectively this projection is located at respectively between this reflecting body and this first substrate, and wherein respectively this projection has a convex-concave surface, and respectively this reflecting body also has a convex-concave surface whereby.

3. semi-penetration semi-reflection type display panel according to claim 1, it is characterized in that, this semi-penetration semi-reflection type display panel comprises a plurality of protrusions in addition, be located at respectively respectively in this echo area, and respectively this protrusion is located at respectively between this transparency electrode and this liquid crystal layer.

4. semi-penetration semi-reflection type display panel according to claim 1, it is characterized in that, respectively this EL part comprises an anode, a luminescent layer and a negative electrode, be located in regular turn respectively on this first substrate of this penetrating region respectively, and respectively this anode is electrically connected to respectively this driving element.

5. semi-penetration semi-reflection type display panel according to claim 1 is characterized in that this semi-penetration semi-reflection type display panel comprises a quarter-wave plate in addition, is arranged at the opposite side of this second real estate to this first substrate.

6. semi-penetration semi-reflection type display panel according to claim 5 is characterized in that this semi-penetration semi-reflection type display panel comprises a polaroid in addition, is arranged on this quarter-wave plate.

7. semi-penetration semi-reflection type display panel according to claim 1 is characterized in that, in this pixel region respectively, this chromatic filter layer is arranged in this echo area.

8. semi-penetration semi-reflection type display panel according to claim 1 is characterized in that, in this pixel region respectively, this chromatic filter layer is arranged in this echo area and this penetrating region.

9. semi-penetration semi-reflection type display panel according to claim 8 is characterized in that, described EL part is a white-light luminescent component.

10. semi-penetration semi-reflection type display panel according to claim 1, it is characterized in that, this semi-penetration semi-reflection type display panel comprises a plurality of second switch elements in addition, be arranged at respectively on this first substrate of this pixel region respectively, and in this pixel region respectively, this second switch element is electrically connected to this driving element.

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