JP2014146006A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device capable of suppressing the deterioration of display fidelity by reducing the occurrence of unevenness in image display.SOLUTION: A liquid crystal display device 1 includes: a first substrate 21 and a second substrate 22 disposed so as to face each other; a columnar spacer 214 having a bottom part 214c fixed onto a second main surface 21b of the first substrate 21 and an apex 214a facing the second substrate 22 and a side part 214b positioned between the apex 214a and the bottom part 214c; a first alignment film 215 covering the columnar spacer 214; a second alignment film 228 disposed on a first main surface 22a of the second substrate 22; and a liquid crystal layer 23 disposed between the first alignment film 215 and the second alignment film 228. The second alignment film 228 has a recess 228A in which the apex 214a is housed, and the recess 228A has a contact surface 228a which is brought into contact with the first alignment film 214 covering the apex 214a and a side surface 228b separated from the first alignment film 215 covering the side part 214b.

Description

  The present invention relates to a liquid crystal display device used for various applications such as a mobile phone, a digital camera, a portable game machine, or a portable information terminal.

  The liquid crystal display device includes a first substrate having a display area on an outer main surface, a second substrate disposed with the inner main surfaces facing each other with respect to the first substrate, and the first substrate and the second substrate. A liquid crystal layer disposed therebetween, and a columnar spacer disposed between the first substrate and the second substrate. The columnar spacer has a bottom fixed on the inner main surface of the first substrate and a top facing the inner main surface of the second substrate.

  In such a liquid crystal display device, the interval between the first substrate and the second substrate is made uniform by columnar spacers.

JP 2001-133791 A

  In recent years, a liquid crystal display device is often used in combination with a touch panel or the like, and when a user presses the touch panel, the frequency with which an external force is applied to the liquid crystal display device is increasing.

  However, in such a liquid crystal display device, since the top of the columnar spacer is not fixed on the second substrate, the external force is applied so that the position of the top of the columnar spacer is parallel to the inner main surface of the second substrate. May fluctuate. Depending on the magnitude of this external force, the position of the top of the columnar spacer may be greatly displaced, and the top of the columnar spacer may not return to its original position. Therefore, the interval between the first substrate and the second substrate becomes non-uniform, and the interval between the first substrate and the second substrate becomes non-uniform, thereby causing uneven image display and reducing the display quality. There was a problem that there was.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a liquid crystal display device that can reduce unevenness in image display and suppress deterioration in display quality.

The liquid crystal display device of the present invention includes a first substrate having a display area on an outer main surface, a second substrate disposed with the inner main surfaces facing each other with respect to the first substrate, and the display area. A plurality of columnar spacers having a bottom portion fixed on the inner main surface of the first substrate, an apex portion facing the inner main surface of the second substrate, and a side portion positioned between the top portion and the bottom portion. And a first insulating film disposed on the inner main surface of the first substrate so as to cover the plurality of columnar spacers, and an inner main surface of the second substrate overlapping the display region. The first display electrode, the second display electrode for generating an electric field between the first display electrode, and the first display electrode are disposed on the inner main surface of the second substrate so as to cover the first display electrode. The second insulating film formed, the first insulating film overlapping the display region, and the first insulating film A liquid crystal layer disposed between the insulating films, wherein the second insulating film has a recess that accommodates the top of the columnar spacer, and the recess covers the top of the columnar spacer. It has a contact surface that contacts the film and a side surface that is separated from the first insulating film that covers the side portion of the columnar spacer.

  According to the liquid crystal display device of the present invention, it is possible to reduce the occurrence of unevenness in image display and to suppress the deterioration of display quality.

It is a top view showing the liquid crystal display device in the 1st Embodiment of this invention. It is sectional drawing along the II line | wire of FIG. It is the top view to which R vicinity of FIG. 1 was expanded. It is a top view showing the electrode, wiring, and columnar spacer which were provided on the 2nd board | substrate which overlaps a display area. It is sectional drawing along the II-II line of FIG. It is sectional drawing to which the columnar spacer of FIG. 5 was expanded. It is a top view showing the liquid crystal display device in the 2nd Embodiment of this invention. It is sectional drawing along the III-III line of FIG. It is a top view showing the liquid crystal display device in the 3rd Embodiment of this invention. It is sectional drawing along the IV-IV line of FIG. It is a top view showing other shapes of a crevice.

[First Embodiment]
A liquid crystal display device 1 according to a first embodiment of the present invention will be described with reference to FIGS.

  The liquid crystal display device 1 includes a liquid crystal panel 2, a light source device 3 that emits light toward the liquid crystal panel 2, a first polarizing plate 4 that is disposed on the liquid crystal panel 2, and the liquid crystal panel 2 and the light source device 3. And a second polarizing plate 5 disposed therebetween.

  In the liquid crystal panel 2, the first substrate 21 and the second substrate 22 are disposed to face each other, a liquid crystal layer 23 is disposed between the first substrate 21 and the second substrate 22, and a sealing material is provided so as to surround the liquid crystal layer 23. 24 are arranged. A driver IC 25 is disposed on the second substrate 22 and a circuit substrate 26 is connected thereto.

The first substrate 21 has a first main surface 21a having a non-display area E _ND positioned outside the display region E _D and the display area E _D for displaying an image, and the first major surface 21a positioned on the opposite side And a second main surface 21b. The first substrate 21 is formed of a light-transmitting material such as glass or plastic.

On the second main surface 21b of the first substrate 21, a light shielding film 211, a color filter 212, and a first planarization film 213 are formed.
A columnar spacer 214 and a first alignment film 215 are arranged.

The light shielding film 211 has a function of shielding light. The light shielding film 211 is disposed on the second main surface 21 b of the first substrate 21. The light shielding film 211 is provided with is located in a region overlapping with the display area E _D in plan view, a grid pattern along the outer periphery of each pixel P. The light shielding film 211 is also provided in a region overlapping the non-display area E _ND to surround the display area E _D in plan view. Examples of the material of the light shielding film 211 include a resin to which a dye or pigment having a high light shielding property (for example, black) is added, or a metal such as chromium.

The color filter 212 has a function of transmitting only a specific wavelength of visible light. The plurality of color filters 212 are located on the second main surface 21 b of the first substrate 21 and are provided for each pixel P. Each color filter 212 has one of red (R), green (G), and blue (B). Further, the color filter 212 is not limited to the above-described color, for example, yellow (
Y), white (W) and the like. Examples of the material of the color filter 212 include a resin to which a dye or a pigment is added.

The first planarization film 213 is provided on the second main surface 21b of the first substrate 21 so as to cover the light shielding film 211 and the color filter 212. The first planarizing film 213 is continuously formed over the region overlapping the region overlapping the display area E _D and the non-display area E _ND. The first planarization film 213 is formed of an organic material such as an acrylic resin, an epoxy resin, or a polyimide resin. The film thickness of the planarizing film 213 is set in the range of 1 μm to 5 μm, for example.

The columnar spacer 214 has a function of controlling the distance between the first substrate 21 and the second substrate 22. The plurality of columnar spacers 214 are provided between the first substrate 21 and the second substrate 22. One end of the columnar spacer 214 is fixed to a member on the first substrate 21. Specifically, the columnar spacer 214 is fixed to the first planarization film 213. Note that the columnar spacers 214 in this embodiment are fixed to members on the first substrate 21, but the present invention is not limited to this, and they may be fixed to members on the second substrate 22. The columnar spacer 214 is formed of a resin material such as acrylic resin or epoxy resin. Note that the Young's modulus of the material of the columnar spacer 214 in the present embodiment is, for example, 4.8 GPa.

Further, as shown in FIG. 3, a plurality of columnar spacers 214 together are arranged in a region overlapping the display region E _D, it is also arranged in a region overlapping with the non-display area E _ND. In a region overlapping the region overlapping with the display area E _D and the non-display area E _ND, a plurality of columnar spacers 214 overlap the light shielding film 211. Also, as shown in FIG. 6, each columnar spacer 214 has a top 214.
a, side 214b and bottom 214c.

The top portion 214 a is a portion facing the second substrate 22. The bottom 214c is a part fixed to a member on the first substrate 21. The side portion 214b is a portion formed from the top portion 214a to the bottom portion 214c, and is a portion located between the top portion 214a and the bottom portion 214c. Further, the area of the bottom 214c is larger than the area of the top 214a in plan view. In addition, the diameter of the top part 214a in this embodiment is set to 10 micrometers-20 micrometers, for example. Further, the top portion 214a and the bottom portion 214c of the columnar spacer 214 of the present embodiment are circular, but not limited thereto,
For example, it may be rectangular or triangular.

When the columnar spacer 214 is fixed to a member on the second substrate 22, the top portion 214 a is a portion facing the first substrate 21, and the bottom portion 214 c is fixed to the member on the second substrate 22. It becomes a part.

  As a method for forming the columnar spacer 214, a resin film is formed by applying a resin on the second main surface 21b of the first substrate 21 on which the first planarizing film 213 is formed. Then, the columnar spacer 214 can be formed by exposing a predetermined portion of the resin film using a mask, removing the exposed portion of the resin film by development, and curing by heating.

  The first alignment film 215 has a function of controlling the alignment of liquid crystal molecules in the liquid crystal layer 23. The first alignment film 215 is provided on the first planarization film 213 so as to cover the plurality of columnar spacers 214. That is, the first alignment film 215 covers the top part 214a and the side part 214b of the columnar spacer 214.

Examples of the material of the first alignment film 215 include a resin such as a polyimide resin. Also, the first alignment film 215
Is subjected to orientation treatment. By this alignment treatment, the initial alignment direction of liquid crystal molecules located in the vicinity of the surface of the first alignment film 215 (the alignment direction when no electric field is applied) can be set. Examples of the alignment treatment include a rubbing treatment using a rubbing cloth, but are not limited thereto, and for example, a photo-alignment treatment using polarized ultraviolet light may be used.

  The second substrate 22 has a first main surface 22a facing the second main surface 21b of the first substrate 21, and a second main surface 22b located on the opposite side of the first main surface 22a. The second substrate 22 is made of the same material as the first substrate 21.

A plurality of gate wirings 221 are provided on the first main surface 22 a of the second substrate 22, and a gate insulating film 222 is provided so as to cover the plurality of gate wirings 221. A plurality of source wirings 223 are provided on the gate insulating film 222. A second planarizing film 224 is provided on the gate insulating film 222 so as to cover the plurality of source wirings 223. A common electrode 225 is provided on the second planarizing film 224. An interlayer insulating film 226 is provided on the second planarization film 224 so as to cover the common electrode 225, and a plurality of signal electrodes 227 are formed on the interlayer insulating film 226 so as to overlap the common electrode 225. Is provided. Further, a second alignment film 228 is provided on the interlayer insulating film 226 so as to cover the signal electrode 227.

The gate wiring 221 has a function of applying a gate voltage supplied from the driver IC 25 to the thin film transistor TFT. As shown in FIGS. 4 and 5, the gate wiring 221 is located on the first major surface 22 a of the second substrate 22 and extends in the X direction. The plurality of gate wirings 221 are arranged in the Y direction. The gate wiring 221 is formed of a conductive material, for example, aluminum, molybdenum, titanium, neodymium, chromium, copper, or an alloy containing these.

  The gate wiring 221 is formed by the following method, for example.

  First, a conductive film is formed on the first main surface 22a of the second substrate 22 by sputtering, vapor deposition, or chemical vapor deposition. A photosensitive resin is applied to the surface of the conductive film, and an exposure process and a development process are performed on the applied photosensitive resin, whereby a pattern having a desired shape is formed on the photosensitive resin. Next, the conductive film is etched with an etching solution to make the film into a desired shape, and then the applied photosensitive resin is peeled off. By forming and patterning in this manner, the gate wiring 221 can be formed.

The gate insulating film 222 is provided on the first main surface 22a so as to cover the gate wiring 221. The gate insulating film 222 is formed using an insulating material such as silicon nitride or silicon oxide. The gate insulating film 222 can be formed on the first main surface 22a of the second substrate 22 by the above-described sputtering method, vapor deposition method, chemical vapor deposition method, or the like.

The source wiring 223 has a function of applying a signal voltage supplied from the driver IC 25 to the signal electrode 227 via the thin film transistor TFT. As shown in FIGS. 4 and 5, the plurality of source lines 223 extend in the Y direction. The plurality of source lines 223 are provided on the gate insulating film 222 and are arranged in the X direction. The source wiring 223 may be formed using the same material as the gate wiring 221. The source wiring 223 can be formed by a method similar to that for the gate wiring 221. Although the source wiring 223 in this embodiment extends in a straight line, the present invention is not limited to this, and may be bent and extended.

  Note that the pixel P is a region surrounded by a plurality of gate wirings 221 and a plurality of source wirings 223.

The thin film transistor TFT includes a semiconductor layer such as amorphous silicon, polysilicon, or an oxide semiconductor, a source electrode provided on the semiconductor layer, connected to the source wiring 223, and a drain electrode. The drain electrode of the thin film transistor TFT is
It is connected to the signal electrode 227 via a drain wiring and a contact hole (not shown).

In the thin film transistor TFT, the resistance of the semiconductor layer between the source electrode and the drain electrode changes according to the voltage applied to the semiconductor layer via the gate wiring 221, whereby writing or non-writing of the image signal to the signal electrode 227 is performed. Be controlled.

The second planarization film 224 is provided on the gate insulating film 222 so as to cover the gate wiring 221, the source wiring 223, and the thin film transistor TFT. The second planarization film 224 is formed of an organic material, and examples thereof include an acrylic resin, an epoxy resin, and a polyimide resin. The film thickness of the second planarizing film 224 is set in the range of 1 μm to 5 μm, for example. Note that, from the viewpoint of reducing parasitic capacitance, it is preferable to increase the thickness of the second planarization film 224.

Further, the second planarizing film 224 in the present embodiment has a small film thickness in a region overlapping with the columnar spacer 214. The film thickness of the second planarization film 224 in a predetermined region (region overlapping the columnar spacer 214) can be adjusted by controlling the exposure amount using, for example, a halftone mask. The adjustment of the film thickness of the second planarizing film 224 is not limited to the case where a halftone mask is used. For example, the film thickness of the second planarizing film 224 is controlled by controlling the exposure amount using a normal mask. Adjustments may be made.

  The common electrode 225 has a function of generating an electric field with the signal electrode 227 by a voltage applied from the driver IC 25. The common electrode 225 is provided on the second planarization film 224. The common electrode 225 is provided both inside and outside the pixel P.

  The common electrode 225 is formed of a light-transmitting material having conductivity, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ATO (Antimony Tin Oxide), AZO (Al-Doped Zinc Oxide), tin oxide. , Formed of zinc oxide or conductive polymer.

The interlayer insulating film 226 is provided on the second planarizing film 224 so as to cover the common electrode 225. The interlayer insulating film 226 may be formed using a material similar to that of the gate insulating film 222.

  The signal electrode 227 has a function of generating an electric field with the common electrode 225 by a voltage applied from the driver IC 25. The plurality of signal electrodes 227 are disposed on the interlayer insulating film 226. In each pixel P, a plurality of signal electrodes 227 are arranged along the X direction. Each signal electrode 227 extends in the Y direction. Each signal electrode 227 may be bent and extend in the Y direction.

In the liquid crystal display device 1, the signal electrode 227 is disposed on the common electrode 225 via the interlayer insulating film 226. However, the present invention is not limited to this, and the common electrode 225 is disposed on the signal electrode 227 via the interlayer insulating film 226. You may arrange. Further, the signal electrode 227 and the common electrode 225 may be disposed on the same plane.

Further, the liquid crystal display device 1 employs a lateral electric field method in which the direction of liquid crystal molecules in the liquid crystal layer 23 is controlled by an electric field generated between the signal electrode 227 and the common electrode 225 disposed on the second substrate 22. However, it is not limited to this. That is, even if a common electrode 225 is disposed on the first substrate 21 and a vertical electric field method is employed in which an electric field is generated between the common electrode 225 on the first substrate 21 and the signal electrode 227 on the second substrate 22. Good.

The second alignment film 228 has a function of controlling the alignment of liquid crystal molecules in the liquid crystal layer 23. Second alignment film 228
Is provided on the interlayer insulating film 226 so as to cover the plurality of signal electrodes 227. Second alignment film 228
Examples of the material include a resin such as a polyimide resin.

The second alignment film 228 is subjected to an alignment process. As the alignment treatment, the first
This is the same as that described for the alignment film 215.

The second alignment film 228 has a recess 228A. The recess 228A is provided in a region overlapping the columnar spacer 214 in plan view. The concave portion 228A accommodates the top portion 214a of the columnar spacer 214. The diameter of the recess 228A is larger than the diameter of the top 214a of the columnar spacer 214. In addition,
In the present embodiment, by reducing the thickness of the second planarizing film 224 in the region overlapping the columnar spacer 214, the recess 228A is formed in the second alignment film 228 disposed on the second planarizing film 224. ing.

The recess 228A of the second alignment film 228 has a contact surface 228a and a side surface 228b. Contact surface 228a
Is a portion facing the top 214a of the columnar spacer 214. Further, the contact surface 228 a is in contact with the first alignment film 215 that covers the columnar spacer 214. That is, the second alignment film 228 is in contact with the first alignment film 215 on the contact surface 228a. Further, the side surface 228b is a portion facing the side portion 214b of the columnar spacer 214. The side surface 228 b is separated from the first alignment film 215 that covers the side portion 214 b of the columnar spacer 214. That is, the side surface 228 b is not in contact with the first alignment film 215 that covers the side portion 214 b of the columnar spacer 214. Note that the side surface 228b in this embodiment is disposed so as to surround the columnar spacer 214 in plan view. Further, the recess 228A of the present embodiment is circular in plan view, but is not limited to this. The diameter of the recess 228A in this embodiment is, for example, 25 μm to 35
The depth of the recess 228A is set to 0.1 μm to 0.5 μm, for example.

  In the liquid crystal display device 1, the recess 228 </ b> A of the second alignment film 228 covers the contact surface 228 a that contacts the first alignment film 215 that covers the top 214 a of the columnar spacer 214 and the first alignment film 215 that covers the side 214 b of the columnar spacer 214. And the top portion 214a is accommodated. Thus, even if an external force is applied to the liquid crystal display device 1 and the position of the top 214a of the columnar spacer 214 fluctuates in the X direction, the first alignment film 215 that covers the side 214b of the columnar spacer 214 becomes the side surface of the recess 228A. Since it hits 228b, it can suppress that the position of the top part 214a shifts | deviates greatly. Therefore, it is possible to reduce the situation where the top portion 214a of the columnar spacer 214 does not return to the original position, so that the non-uniform spacing between the first substrate 21 and the second substrate 22 is suppressed, and unevenness in image display occurs. Can be reduced.

Further, the side surface 228b of the recess 228A is separated from the first alignment film 215 that covers the side portion 214b of the columnar spacer 214 and is not in contact therewith. When the side surface 228b of the recess 228A and the first alignment film 215 covering the side portion 214b of the columnar spacer 214 are brought into contact with each other, the first substrate 21 on which the columnar spacer 214 is formed and the recess 228A are formed in the manufacturing process of the liquid crystal display device. When the first substrate 21 and the second substrate 22 are misaligned when the second substrate 22 on which the second alignment film 218 having the second alignment film 218 is bonded via the sealant 24, the top 214a of the columnar spacer 214 is displaced. There is a high possibility that it will not be accommodated in the recess 228A. Since the top 214a of the columnar spacer 214 is not accommodated in the recess 228A, the distance between the first substrate 21 and the second substrate 22 tends to be non-uniform.

On the other hand, when the side surfaces 228b of the recesses 228A are separated from the first alignment film 215 that covers the side portions 214b of the columnar spacers 214, the first substrate 21 and the second substrate 22 are bonded together. Board 21
Even if the second substrate 22 is displaced, there is a space that allows the displacement in the recess 228A. Therefore, the top 214a of the columnar spacer 214 is easily accommodated in the recess 228A. It is possible to reduce non-uniform spacing with the substrate 22 and to easily mass-produce liquid crystal display devices with high display quality.

In the liquid crystal display device 1, the side surface 228b of the recess 228A is an inclined surface that becomes narrower toward the contact surface 228a. That is, the side surface 228b of the recess 228A is inclined with respect to the contact surface 228a. As a result, even when an external force is applied and the position of the top portion 214a of the columnar spacer 214 is displaced, it is easy to return the top portion 214a of the columnar spacer 214 to the original position by inclining the side surface 228b. It is possible to suppress the non-uniform spacing between the two substrates 22 and reduce the occurrence of unevenness in image display.

  The liquid crystal layer 23 is provided between the first substrate 21 and the second substrate 22. The liquid crystal layer 23 includes molecules such as nematic liquid crystal.

  The driver IC 25 has a function of controlling driving of the gate wiring 221 and the source wiring 223. The driver IC 25 is located on the second main surface 22 a of the second substrate 22.

  The circuit board 26 is electrically connected to the liquid crystal panel 2. The circuit board 26 has a base, a wiring pattern, and circuit electrode terminals, and has a function of supporting the wiring pattern and circuit electrode terminals. The base is formed of an insulating material, for example, a flexible material such as polyimide resin.

  The liquid crystal layer 23 is disposed between the first substrate 21 and the second substrate 22. The liquid crystal layer 23 includes liquid crystal molecules such as a nematic liquid crystal, a cholesteric liquid crystal, or a smectic liquid crystal.

  The sealing material 24 has a function of bonding the first substrate 21 and the second substrate 22 together. The sealing material 24 is disposed between the first substrate 21 and the second substrate 22. The sealing material 24 is formed of an organic material such as an epoxy resin.

  The light source device 3 has a function of emitting light toward the liquid crystal panel 2. The light source device 3 includes a light source 31 and a light guide plate 32. In the light source device 3 according to the present embodiment, a point light source such as an LED is employed as the light source 31, but a linear light source such as a cold cathode tube may be employed.

  The first polarizing plate 4 has a function of selectively transmitting light in a predetermined vibration direction. The first polarizing plate 4 is disposed so as to face the first main surface 21 a of the first substrate 21 of the liquid crystal panel 2.

  The second polarizing plate 5 has a function of selectively transmitting light in a predetermined vibration direction. The second polarizing plate 5 is disposed so as to face the second main surface 22 b of the second substrate 22.

[Second Embodiment]
7 and 8 are diagrams showing a main part of the liquid crystal display device 1A according to the second embodiment of the present invention. The liquid crystal display device 1A than a liquid crystal display device 1, together with the second planarizing film 224 is formed with the same thickness, the light shielding film 211 which overlaps the display region E _D the first main surface 22a of the second substrate 22 It differs in that it is placed on top.

  The light shielding film 211 is disposed on the first main surface 22 a of the second substrate 22, specifically, the gate insulating film 222. The light shielding film 211 may be disposed in any layer as long as it is a layer between the first major surface 22a of the second substrate 22 and the second alignment film 228. The light shielding film 211 is disposed so as to overlap the plurality of gate wirings 221 and the plurality of source wirings 223. In FIG. 7, the formation region of the light shielding film 211 is indicated by hatching (broken lines).

The light shielding film 211 has an opening 211 a in a region overlapping the top 214 a of the columnar spacer 214. As shown in FIGS. 7 and 8, the outer periphery of the opening 211a is located outside the outer periphery of the top 214a. In addition, although the opening part 211a of this embodiment is circular shape, it is not restricted to this. In the present embodiment, since the light shielding film 211 has the opening 211a, the recess 228A is formed in the second alignment film 228 disposed on the light shielding film 211.

  That is, in the liquid crystal display device 1A, the thickness of the second planarizing film 224 is not adjusted, and the recess 228A is formed in the second alignment film 228 using the thickness of the light shielding film 211. In addition, although the opening part 211a of the light shielding film 211 of this embodiment penetrates, it does not need to penetrate. In the liquid crystal display device 1A, since the second alignment film 228 has the concave portion 228A, the same effects as those described in the liquid crystal display device 1 can be obtained.

In the liquid crystal display device 1A, the second alignment film 228 is disposed so as to cover the opening 211a of the light shielding film 211 disposed on the first main surface 22a of the second substrate 22. That is, the concave portion 228A is formed in the second alignment film 228 by using the thickness and the formation position of the light shielding film 211. Since the thickness and formation position of the light shielding film 211 can be controlled with high accuracy by the film forming process and the patterning process, the depth of the recess 228A of the second alignment film 228 is adjusted by the thickness of the light shielding film 211, and the formation position of the light shielding film 211 is formed. Thus, by adjusting the width of the recess 228A of the second alignment film 228, the recess 228A can be formed in the desired second alignment film 228 with high accuracy. As a result, when the plurality of recesses 228A are formed in the second alignment film 228, variations in the depth and width of each recess 228A can be easily reduced. Further, since the light shielding film 211 is easily formed with a large thickness, it is easy to form the concave portion 228A having a large depth.

[Third Embodiment]
FIG. 9 and FIG. 10 are diagrams showing a main part of a liquid crystal display device 1B according to the third embodiment of the present invention. In the liquid crystal display device 1B, the second planarizing film 224 is formed with the same thickness as the liquid crystal display device 1, and the conductive film D is provided in a region overlapping the top portion 214a of the columnar spacer 214. Different.

  The conductive film D is disposed on the first main surface 22 a of the second substrate 22, specifically, the gate insulating film 222. The conductive film D is circular. The conductive film D has a cavity Da in a region overlapping the top 214a of the columnar spacer 214. The cavity Da has a circular shape, and the area of the cavity Da is larger than the area of the top 214a of the columnar spacer 214 in plan view.

In the liquid crystal display device 1 </ b> B, the thickness of the second planarizing film 224 is not adjusted, and the recess 228 </ b> A is formed in the second alignment film 228 using the thickness of the conductive film D. The liquid crystal display device 1B includes a second alignment film 228.
Since it has the recess 228A, the same effects as those described in the liquid crystal display device 1 can be obtained.

In the liquid crystal display device 1A, the second alignment film 228 is disposed so as to cover the cavity Da of the conductive film D disposed on the first main surface 22a of the second substrate 22. That is, the second film is formed using the conductive film D.
A recess 228A is formed in the alignment film 228. Since the thickness and formation position of the conductive film D can be controlled with high accuracy by the film forming process and the patterning process, the depth of the recess 228A of the second alignment film 228 is adjusted by the thickness of the conductive film D, and the formation position of the conductive film D Thus, by adjusting the width of the recess 228A of the second alignment film 228, the recess 228A can be formed in the desired second alignment film 228 with high accuracy. As a result, when the plurality of recesses 228A are formed in the second alignment film 228, variations in the depth and width of each recess 228A can be easily reduced. In addition, by adopting a dry etching process when forming the conductive film D, the end surface of the conductive film D can be easily inclined at a desired angle, and the inclination angle of the side surface of the recess 228A can be easily adjusted.

  Further, by forming the recess 228A in the second alignment film 228 using the conductive film D having a hardness higher than that of resin or the like, the recess 228A has strength, so that the top 214a of the columnar spacer 214 and the recess 228A Since the friction can be reduced, even when the top portion 214a of the columnar spacer 214 is displaced, it is easy to return to the original position.

The present invention is not particularly limited to the above-described embodiments, and various changes and improvements can be made within the scope of the gist of the present invention. For example, one end of the columnar spacer 214 in the above embodiment is fixed to the first substrate 21 side, but may be fixed to a member on the second substrate 22. In that case, a recess may be formed in the first alignment film 215.

In the first to third embodiments, the side surface 228b of the recess 228A is separated from the side portion 214b of the columnar spacer 214 and is not in contact with the entire outer periphery of the recess 228A. Absent. That is, as shown in FIG. 11A, the side surface 228b of the recess 228A may be separated from the side portion 214b of the columnar spacer 214 in at least a part of the outer periphery of the recess 228A. Further, as shown in FIG. 11B, the recess 228A may have any shape.

11A and 11B are plan views of the columnar spacer 214 viewed from the second substrate 22 (bottom 214c) side. A region surrounded by a thick broken line indicates the recess 228A, and a region surrounded by a thin broken line indicates the top 214a.

  When the normally black method is adopted for the liquid crystal display device 1, the twist angle of the liquid crystal molecules of the liquid crystal layer 23 at the time of black display becomes 0 °. Here, in the case of black display, when the top 214a of the columnar spacer 214 is displaced in a direction perpendicular to the alignment direction of the liquid crystal molecules due to an external force, the liquid crystal molecules rotate. As compared with the case where the top 214a is displaced in a direction parallel to the alignment direction, display unevenness is likely to occur. Therefore, when the normally black method is employed, at least the recess 228A is columnar in the direction perpendicular to the alignment direction in order to suppress the displacement of the top 214a in the direction perpendicular to the alignment direction of the liquid crystal molecules. The top 214a of the spacer 214 is preferably accommodated.

1 liquid crystal display device 2 liquid crystal panel E _D display region P pixel E _ND non-display region
21 First board
21a First main surface (outer main surface)
21b Second main surface (inner main surface)
211 Shading film
212 Color filter
213 First planarization film
214 Columnar spacer
214a top
214b side
214c Bottom
215 First alignment film (first insulating film)
22 Second board
22a First main surface (inner main surface)
22b Second main surface (outer main surface)
221 Gate wiring
222 Gate insulation film
223 source wiring
224 Second planarization film
225 Common electrode
226 Interlayer insulation film
227 Signal electrode
228 Second alignment film (second insulating film)
228A recess
228a Contact surface
228b side view
23 Liquid crystal layer
24 Sealing material
25 Driver IC
26 Circuit board 3 Light source device
31 Light source
32 Light guide plate 4 First polarizing plate 5 Second polarizing plate

Claims (3)

A first substrate having a display region on an outer main surface; a second substrate disposed with its inner main surfaces facing each other with respect to the first substrate; and the inner side of the first substrate overlapping the display region A plurality of columnar spacers having a bottom fixed on the main surface, a top facing the inner main surface of the second substrate, and a side located between the top and the bottom, and a plurality of the columnar spacers. A first insulating film disposed on the inner main surface of the first substrate so as to cover; a first display electrode disposed on the inner main surface of the second substrate overlapping the display region; A second display electrode for generating an electric field with the first display electrode; a second insulating film disposed on the inner main surface of the second substrate so as to cover the first display electrode; Disposed between the first insulating film and the second insulating film overlapping the display region And a crystal layer,
The second insulating film has a recess that accommodates the top of the columnar spacer,
The recess has a contact surface in contact with the first insulating film covering the top of the columnar spacer and a side surface separated from the first insulating film covering the side portion of the columnar spacer. apparatus.   The liquid crystal display device according to claim 1, wherein the side surface of the recess is an inclined surface that becomes narrower toward the contact surface.   The liquid crystal display device according to claim 1, wherein the recess has a circular shape in plan view.

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