KR20060018399A - Multi-domain liquid crystal display - Google Patents

Abstract

The liquid crystal display according to the present invention includes a first insulating substrate, a first signal line formed on the first insulating substrate, a second signal line formed on the first insulating substrate, and insulated from and intersecting the first signal line. A pixel electrode formed for each pixel defined by crossing the second signal line, a first signal line, a second signal line, and a thin film transistor connected to the pixel electrode, a second insulating substrate facing the first insulating substrate, and a second insulating substrate It is formed on at least one side of the common electrode formed above, the liquid crystal layer formed between the 1st insulating substrate, and the 2nd insulating substrate, the 1st insulating substrate, and the 2nd insulating substrate, and many liquid crystal molecules of a liquid crystal layer are carried out from a pixel. At least one concave or convex, wherein a plurality of domain regulating means divides into domains of Preferably it has a notch on. Accordingly, the liquid crystal display according to the present invention improves the response speed by forming one or more notches at the longitudinal end and the horizontal end of the cutout of the common electrode.

LCD, domain control means, texture, response speed, notch

Description

Multi-domain Liquid Crystal Display {MULTI-DOMAIN LIQUID CRYSTAL DISPLAY}

1 is a layout view illustrating a structure of a thin film transistor array panel for a liquid crystal display according to an exemplary embodiment of the present invention.

2 is a layout view illustrating a structure of an opposing display panel for a liquid crystal display according to an exemplary embodiment of the present invention.

3 is a layout view illustrating a structure of a liquid crystal display according to an exemplary embodiment in which the display panels of FIGS. 1 and 2 of the present invention are aligned and completed;

4 is a cross-sectional view of the liquid crystal display of FIG. 3 taken along the line IV-IV ';

FIG. 5 is a diagram illustrating a state in which directors of liquid crystal molecules are rearranged by notches formed at the longitudinal and transverse ends of the cutout portion of the common electrode.

6A is a view illustrating a state in which textures are generated by distorting liquid crystals in an initial state where a voltage is applied;

FIG. 6B is a view illustrating a state in which textures are reduced by rearranging liquid crystals distorted by two step motions in the same direction as a liquid crystal array in a domain after a time has elapsed while a constant voltage is applied.

<Description of the symbols for the main parts of the drawings>

110: substrate 121, 129: gate line                 

124: gate electrode 140: gate insulating film

151 and 154 semiconductor 161 and 165 resistive contact members

171, 179: data line 173: source electrode

175: drain electrode 180: protective film

181, 182, 185: contact hole 190: pixel electrode

81, 82: contact auxiliary member

271, 272, 273: incision of the common electrode

191, 192, 193: incision of the pixel electrode

277, 278a, 278b, 278c: notch

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device having a vertical alignment mode in which pixels are divided into a plurality of domains in order to obtain a wide viewing angle.

The liquid crystal display is one of the most widely used flat panel display devices. The liquid crystal display includes two display panels on which a field generating electrode is formed and a liquid crystal layer interposed therebetween. It is a display device which controls the transmittance | permeability of the light which passes through a liquid crystal layer by rearranging.

Among the liquid crystal display devices currently used mainly, the field generating electrodes are provided on each of two display panels. Among them, a liquid crystal display device having a structure in which a plurality of pixel electrodes are arranged in a matrix form on one display panel and one common electrode covering the entire display panel on the other display panel is mainstream. The display of an image in this liquid crystal display device is performed by applying a separate voltage to each pixel electrode. To this end, a thin film transistor, which is a three-terminal element for switching a voltage applied to a pixel electrode, is connected to each pixel electrode, and a gate line for transmitting a signal for controlling the thin film transistor and a data line for transmitting a voltage to be applied to the pixel electrode are provided. Install on the display panel.

However, it is an important disadvantage that the liquid crystal display device has a narrow viewing angle. In order to overcome these disadvantages, various methods for widening the viewing angle have been developed. Among them, the liquid crystal molecules are oriented vertically with respect to the upper and lower substrates, and the pixel is formed by forming a constant incision pattern or protrusion on the pixel electrode and the common electrode as the opposite electrode. The method of partitioning into multiple domains is gaining popularity.

However, in the vertical alignment mode liquid crystal display having protrusions or cutout patterns, spots or afterimages may occur in the protrusions or cutout patterns, or stains may remain when the screen is rubbed. One of the causes is that the liquid crystal molecules arranged at the boundary of the domain are rearranged by the collision or collision due to the arrangement of the liquid crystal molecules arranged in the domain, because the directors of the liquid crystal molecules are arranged irregularly and unstable. .

In particular, the liquid crystals 3 are distorted as shown in FIG. 6A in the initial state where voltage is applied to the portions having the inclination angle of 135 degrees among the protrusions or the cutting patterns 272 to generate texture. When time elapses in a state where a constant voltage is applied, the distorted liquid crystals 3 are rearranged in the same direction as the liquid crystal array inside the domain by two step motions as shown in FIG. 6B. Is reduced.

However, when the driving voltage is increased to obtain high luminance, the distortion region of the liquid crystal array is widened to the inside of the domain, thereby widening the two step motion region of the texture. As the two-step motion region is widened, the response speed becomes slow.

An object of the present invention is to provide a liquid crystal display device having improved response speed by minimizing a two step motion region of a texture.

The liquid crystal display according to the present invention includes a first insulating substrate, a first signal line formed on the first insulating substrate, a second signal line formed on the first insulating substrate and insulated from and intersecting the first signal line. A pixel electrode formed for each pixel defined by the intersection of the first signal line and the second signal line, the thin film transistor connected to the first signal line, the second signal line, and the pixel electrode, and facing the first insulating substrate. At least one of a second insulating substrate, a common electrode formed on the second insulating substrate, a liquid crystal layer formed between the first insulating substrate and the second insulating substrate, the first insulating substrate and the second insulating substrate And a plurality of domain regulating means for dividing the liquid crystal molecules of the liquid crystal layer into a plurality of domains in the pixel. Of the domain regulating means preferably has a horizontal part and vertically concave or convex portion, at least one notch.

In addition, the liquid crystal contained in the liquid crystal layer preferably has negative dielectric anisotropy and the long axis of the liquid crystal is vertically aligned with respect to the first and second substrates.

In addition, it is preferable that an oblique portion of the domain regulating means is substantially ± 45 degrees with respect to the first signal line.

Further, it is preferable that the domain restricting means is substantially mirror-symmetrical with respect to the upper and lower bisectors of the pixel.

In addition, it is preferable that the domain regulating means is a cutout portion of the common electrode or the pixel electrode.

In addition, the domain regulating means is preferably a protrusion formed on the common electrode or the pixel electrode.

Moreover, it is preferable that the horizontal part or the vertical part of the said domain regulation means is the edge part of the said incision part or protrusion.

Moreover, it is preferable that the notch which is concave or convex is formed in the diagonal part of the said domain regulation means.

Then, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like parts are designated by like reference numerals throughout the specification. When a part of a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the other part being "right over" but also another part in the middle. On the contrary, when a part is "just above" another part, there is no other part in the middle.

A liquid crystal display according to an exemplary embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

1 is a layout view showing a structure of a thin film transistor array panel for a liquid crystal display according to an exemplary embodiment of the present invention, and FIG. 2 is a layout view showing a structure of an opposing display panel for a liquid crystal display according to an exemplary embodiment of the present invention. 3 is a layout view illustrating a structure of a liquid crystal display according to an exemplary embodiment in which the display panels of FIGS. 1 and 2 are aligned, and FIG. 4 is a line IV-IV 'of the liquid crystal display of FIG. It is a cross-sectional view cut along.

The liquid crystal display device is formed of a liquid crystal molecule that is formed between the thin film transistor array panel 100 on the lower side and the upper opposing display panel 200 facing them, and is substantially perpendicular to the two display panels 100 and 200. It consists of a liquid crystal layer 3 including 310. In this case, the alignment layers 11 and 21 are formed on the display panels 100 and 200, and the alignment layers 11 and 21 form the liquid crystal molecules 310 of the liquid crystal layer 3 with respect to the display panels 100 and 200. It is preferred that it is a vertical alignment mode that allows it to be oriented vertically. In addition, upper and lower polarizers 12 and 22 are attached to outer surfaces of the upper panel 200 and the lower panel 100, respectively.

The thin film transistor array panel 100 made of a transparent insulating material such as glass is made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO), and includes a pixel electrode having cutouts 191, 192, and 193. 190 is formed, and each pixel electrode 190 is connected to a thin film transistor to receive an image signal voltage. In this case, the thin film transistor is connected to the gate line 121 for transmitting the scan signal and the data line 171 for transmitting the image signal, respectively, to turn on and off the pixel electrode 190 according to the scan signal. . Here, the pixel electrode 190 may not be made of a transparent material in the case of a reflective liquid crystal display, and in this case, the lower polarizer 12 is also unnecessary.

It is also made of a transparent insulating material such as glass, and the opposite display panel 200 facing the thin film transistor array panel 100 includes a black matrix 220 and a color filter of red, green, and blue to prevent light leakage from the edge of the pixel. The common electrode 270 formed of the transparent conductive material such as 230 and ITO or IZO is formed. The black matrix 220 may be formed not only in the peripheral portion of the pixel region but also in the portion overlapping the cutouts 271, 272, and 273 of the common electrode 270. This is to prevent light leakage caused by the cutouts 271, 272, and 273.

Next, the thin film transistor array panel 100 will be described in more detail.                     

In the thin film transistor array panel 100, a plurality of gate lines 121 may be formed on the lower insulating substrate 110 to transfer gate signals. The gate line 121 mainly extends in the horizontal direction, and a part of each gate line 121 forms a plurality of gate electrodes 124. The gate electrode 124 is formed in the form of a protrusion in the gate line 121, and as shown in the present embodiment, the gate line 121 may have a contact portion for transmitting a gate signal from the outside to the gate line 121. In this case, the end portion 129 of the gate line 121 has a wider width than the other portion, but in other cases, the end portion of the gate line 121 of the gate driving circuit is formed directly on the substrate 110. It is directly connected to the output.

The storage electrode wirings are formed on the insulating substrate 110 in the same layer as the gate lines 121. Each storage electrode wiring includes a storage electrode line 131 extending parallel to the gate line 121 at the edge of the pixel region and a plurality of storage electrodes 133a, 133b, 133c, and 133d extending therefrom. . The pair of storage electrodes 133a, 133b, 133c, and 133d extend in the vertical direction and are connected to each other by the vertical electrode 133a and 133b which are connected to each other by the storage electrode line 131 extending in the horizontal direction, and the pixel electrode formed thereafter ( An oblique portion 133c and 133d overlapping the cutouts 191 and 193 of 190 and connecting the vertical portions 133a and 133b. These diagonal lines 133c and 133d serve as a control electrode for controlling the texture occurring at the center of the cutouts 191 and 193.

The gate line 121 and the sustain electrode wirings 131, 133a, 133b, 133c, and 133d are made of metal such as Al, Al alloy, Ag, Ag alloy, Cr, Ti, Ta, Mo, or the like. As shown in FIG. 4, the gate line 121 and the sustain electrode wirings 131, 133a, 133b, 133c, and 133d of the present embodiment are formed of a single layer, but have excellent physicochemical properties such as Cr, Mo, Ti, Ta, and the like. It may be made of a double layer including a metal layer of the Al-based or Ag-based metal layer having a low specific resistance. In addition, the gate line 121 and the sustain electrode wirings 131, 133a, 133b, 133c, and 133d may be made of various metals or conductors.

The gate line 121 and the sustain electrode wirings 131, 133a, 133b, 133c, and 133d are inclined side by side, and the inclination angle with respect to the horizontal plane is preferably 30 to 80 °.

A gate insulating layer 140 made of silicon nitride (SiNx) or the like is formed on the gate line 121 and the storage electrode wirings 131, 133a, 133b, 133c, and 133d.

A plurality of drain electrodes 175, including a plurality of data lines 171, are formed on the gate insulating layer 140. Each data line 171 extends mainly in a vertical direction and has a source electrode 173 extending from the data line 171 by extending a plurality of branches toward each drain electrode 175. The contact unit 179 located at one end of the data line 171 transfers an image signal from the outside to the data line 171. In addition, a leg metal piece 172 overlapping the gate line 121 is formed on the gate insulating layer 140.

Like the gate line 121, the data line 171 and the drain electrode 175 may be made of a material such as chromium and aluminum, and may be formed of a single layer or multiple layers.

Under the data line 171 and the drain electrode 175, a plurality of linear semiconductors 151 that extend mainly vertically along the data line 171 are formed. Each linear semiconductor 151 made of amorphous silicon extends toward each gate electrode 124, the source electrode 173, and the drain electrode 175 to have a channel portion 154.

Between the semiconductor 151, the data line 171, and the drain electrode 175, a plurality of linear ohmic contacts 161 and island-like ohmic contacts 165 for reducing contact resistance therebetween, respectively. Is formed. The ohmic contact 161 is made of amorphous silicon doped with silicide or n-type impurities at a high concentration, and has an ohmic contact 163 extending into a branch, and the island-type ohmic contact 165 has a gate electrode 124. Facing the ohmic contact 163.

On the data line 171 and the drain electrode 175, a-Si: C: O, a-Si formed by plasma enhanced chemical vapor deposition (PECVD), an organic material having excellent planarization characteristics, and photosensitivity. A protective film 180 made of a low dielectric constant insulating material such as: O: F or silicon nitride is formed.

The passivation layer 180 includes a plurality of contact holes 185 and 182 exposing at least a portion of the drain electrode 175 and an end portion 179 of the data line 171, respectively. Meanwhile, the end portion 129 of the gate line 121 also has a contact portion for connecting with an external driving circuit, and the plurality of contact holes 181 pass through the gate insulating layer 140 and the passivation layer 180 to pass through the gate line. Expose the end of (121).

A plurality of contact assistants 82 and 81 are formed on the passivation layer 180, including a plurality of pixel electrodes 190 having cutouts 191, 192, and 193. The pixel electrode 190 and the contact auxiliary members 81 and 82 may use a transparent conductor such as indium tin oxide (ITO) or indium zinc oxide (IZO), or an opaque conductor having excellent light reflection characteristics such as aluminum (Al). Form.

The cutouts 191, 192, and 193 formed in the pixel electrode 190 may be divided into the horizontal cutout 192 formed in the horizontal direction at a position that half-divides the pixel electrode 190. And diagonally cut portions 191 and 193 formed in diagonal directions, respectively, in the upper and lower portions of the upper and lower portions. The cutout 192 penetrates from the right side to the left side of the pixel electrode 190, and the inlet is broadly symmetrically extended. Accordingly, the pixel electrode 190 is substantially mirror-symmetrical with respect to a line (a line parallel to the gate line) that bisects the pixel region defined by the intersection of the gate line 121 and the data line 171, respectively.

At this time, the upper and lower oblique cuts 191 and 193 are perpendicular to each other, in order to evenly distribute the direction of the fringe field in four directions.

In addition, a storage wiring connecting bridge 84 is formed on the same layer as the pixel electrode 190 to connect the storage electrode 133a and the storage electrode line 131 of the pixels adjacent to each other across the gate line 121. The storage wiring connecting bridge 84 is in contact with the storage electrode 133a and the storage electrode line 131 through the contact holes 183 and 184 formed over the passivation layer 180 and the gate insulating layer 140. The sustain wiring connection leg 844 overlaps the leg metal piece 172, and these may be electrically connected to each other. The sustain wiring connection bridge 84 serves to electrically connect the entire sustain wiring on the lower substrate 110. This holding wiring can be used to repair the defect of the gate line 121 or the data line 171, if necessary, and the leg metal piece 172 is held with the gate line 121 when irradiating a laser for such repair. It is formed to assist the electrical connection of the wiring connection bridge (84).

In the opposite display panel 200 facing the thin film transistor array panel 100, a black matrix 220 is formed on the upper insulating substrate 210 to prevent light leakage from the pixel edge. The red, green, and blue color filters 230 are formed on the black matrix 220. The planarization film 250 is formed on the entire surface of the color filter 230, and a common electrode 270 having cutouts 271, 272, and 273 is formed thereon. The common electrode 270 is formed of a transparent conductor such as ITO or indium zinc oxide (IZO).

A pair of cutouts 271, 272, and 273 of the common electrode 270 may form 45 ° with respect to the gate line 121 among the cutouts 191, 192, and 193 of the pixel electrode 190. 193 and alternately arranged in parallel with the diagonal line and an end portion overlapping the side of the pixel electrode 190. At this time, the end is classified into a longitudinal end part and a horizontal end part.

Each of the cutouts 271, 272, and 273 of the common electrode 270 includes a notch 277 at an oblique portion. In this case, the notches 277 of the oblique portions of the cutouts 271, 272, and 273 may be modified in various shapes.

Further, at least one notch 278a, 278b, 278c is formed at the longitudinal end and the horizontal end of each of the cutouts of the common electrode.

When the thin film transistor substrate and the opposing display panel having the above structure are aligned and combined, and a liquid crystal material is injected and vertically aligned therebetween, a basic structure of the liquid crystal display according to the present invention is provided.

When the thin film transistor array panel and the color filter display panel are aligned, the cutouts 271, 272, and 273 of the common electrode 270 divide the pixel electrode 190 into a plurality of subregions, respectively.

The portion of the liquid crystal layer 300 between each subregion of the pixel electrode 190 and the corresponding subregion of the common electrode 270 is referred to as a "subregion", and these small regions are applied when an electric field is applied. It is classified into eight types according to the average long axis direction of the liquid crystal molecules located therein, which is referred to as "domain" in the future.

As such, when the thin film transistor array panel 100 and the opposing display panel 200 are aligned, the cutouts 191, 192, and 193 of the pixel electrode 190 and the cutouts 271, 272, and 273 of the reference electrode 270 are aligned. Divides the pixel region into a plurality of domains. These domains are classified into four types according to the average major axis direction of the liquid crystal molecules located therein, and each domain is elongated to have a width and a length.

The shape and function of the notches formed in the domain regulation means will now be described in detail.

As shown in FIGS. 2 and 3, the notches 277 formed on the oblique portions of the cutouts 271, 272, and 273, which are domain regulating means, may have a triangular shape and may have a rectangular, trapezoidal, or semicircular shape. And notch 277 may be convex or concave. In this case, the notch 277 determines the alignment direction of the liquid crystal molecules 310 positioned at the domain boundary corresponding to the cutouts 271, 272, and 273.

Accordingly, in the liquid crystal display according to the exemplary embodiment of the present invention, the liquid crystal molecules arranged at the boundary of the domain may be stably and regularly arranged through the notches 277 to prevent spots or afterimages from occurring at the domain boundary. Can be. In addition, since the liquid crystal molecules 310 arranged at the domain boundary may be stably arranged through the notches 277, the width of the oblique portions of the cutouts 271, 272, and 273 may be narrowed to increase the luminance.

At this time, only one notch 277 may be arranged in one domain regulating means, and a plurality of notch 277 and convex notches 277 may be alternately arranged. In addition, although the notch 277 is disposed only in the cutouts 271, 272, and 273 of the common electrode 270, the notch 277 is formed in the cutouts 191, 192, and 193 of the pixel electrode 190. ) May be disposed on both the thin film transistor array panel 100 and the opposing display panel 200.

In this case, the cutouts 191, 192, and 193 of the pixel electrode 190 and the cutouts 271, 272, and 273 of the common electrode 270 act as domain regulating means for dividing and aligning the liquid crystal molecules. As a means, a protrusion of an inorganic material or an organic material may be formed on or under the pixel electrode 190 and the common electrode 270 instead of the cutouts 271, 272, 273, 191, 192, and 193. Can be placed together on the protrusions.

FIG. 5 illustrates a rearrangement of the directors of the liquid crystal molecules by one or more notches 278a, 278b, and 278c formed at the longitudinal and transverse ends of the cutout of the common electrode.

As shown in FIG. 5, a vertical end portion of the cutouts 271, 272, and 273 of the common electrode 270 that forms an angle of 45 ° with respect to the gate line 121 and a longitudinal end portion of the cutout of the common electrode may be formed as shown in FIG. 5. It is 135 degrees inclined. In addition, an oblique portion that forms a 45 ° angle with respect to the gate line 121 among the cutout portions 271, 272, and 273 of the common electrode 270 and a horizontal end portion of the cut portion of the common electrode also have an inclination of 135 degrees. .

The notches 278a, 278b, and 278c formed at the longitudinal or transverse ends of the cutouts 271, 272, and 273 may have a triangular shape and may have a rectangular, trapezoidal, or semicircular shape. In addition, the notches 278a, 278b, and 278c may be convex or concave.

As shown in FIG. 5, the notch 278b intentionally forms a singular point 50 in the cutout 272 to greatly increase the elastic energy of the liquid crystal molecules 310 positioned around the singular point 50. It accumulates and determines the arrangement direction of the liquid crystal molecules 310 in advance.

Therefore, the two-step motion which occurs in the part in which the diagonal part and the horizontal direction or the vertical end inclined at 135 degrees among the cutouts 271, 272, and 273 of the common electrode 270 is inclined.

That is, by determining the arrangement direction of the liquid crystal molecules 310 positioned at the horizontal end or the vertical end of the cutouts 271, 272, and 273 by the notch, the liquid crystal as the driving time of the driving voltage elapses. The phenomenon that the distortion region of the array is widened inside the domain is suppressed.

Therefore, when a high driving voltage is applied, the distortion region of the liquid crystal array is widened to the inside of the domain as the driving time of the driving voltage is applied, thereby widening the two step motion region of the texture and preventing the response speed from slowing down. Can be.

Only one of these notches 278a, 278b, and 278c may be disposed at the transverse or longitudinal ends of the incisions 271, 272, and 273, and alternately the concave notches 277 and the convex notches 277. You can also place it. Further, in the previous embodiment, notches 278a, 278b, and 278c are disposed only at the horizontal or vertical ends of the cutouts 271, 272, and 273 of the common electrode 270, but the cutout of the pixel electrode 190 is performed. The notches 278a, 278b, and 278c may be disposed at the horizontal or vertical ends of the portions 191, 192, and 193, and may be disposed on both the thin film transistor array panel 100 or the opposing display panel 200. .

In this case, the notches 278a, 278b, and 278c may have an inorganic material or an organic material formed on or below the pixel electrode 190 and the common electrode 270 instead of the cutouts 271, 272, 273, 191, 192, and 193. It may be formed in a concave or convex shape on the projection.

Although the preferred embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

The liquid crystal display according to the present invention improves the response speed by forming one or more notches at the longitudinal end and the horizontal end of the cutout of the common electrode.

Claims (8)

First insulating substrate, A first signal line formed on the first insulating substrate, A second signal line formed on the first insulating substrate and insulated from and intersecting the first signal line; A pixel electrode formed for each pixel defined by the crossing of the first signal line and the second signal line; A thin film transistor connected to the first signal line, the second signal line, and the pixel electrode; A second insulating substrate facing the first insulating substrate, A common electrode formed on the second insulating substrate, A liquid crystal layer formed between the first insulating substrate and the second insulating substrate, A plurality of domain restricting means formed on at least one side of the first insulating substrate and the second insulating substrate and dividing the liquid crystal molecules of the liquid crystal layer into a plurality of domains in the pixel; Including; And a horizontal portion or a vertical portion of the plurality of domain regulating means has at least one notch, which is concave or convex. In claim 1, The liquid crystal contained in the liquid crystal layer has negative dielectric anisotropy and the liquid crystal has a long axis oriented perpendicular to the first and second substrates. In claim 1, And wherein an oblique portion of the domain regulating means is substantially ± 45 degrees with respect to the first signal line. In claim 1, And the domain restricting means is substantially mirror-symmetrical with respect to the upper and lower bisectors of the pixel. In claim 1, And the domain regulating means is a cutout of the common electrode or the pixel electrode. In claim 1, And the domain regulating means is a protrusion formed on the common electrode or the pixel electrode. In claim 5 or 6, A horizontal portion or a vertical portion of the domain regulating means is an end portion of the cutout or protrusion. In claim 3, And a concave or convex notch is formed in an oblique portion of the domain regulating means.

Images