JP2011027851A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress degradation of display quality due to a peripheral temperature change. <P>SOLUTION: A liquid crystal display device includes: a film substrate 41; a film substrate 42 facing the film substrate 41; an ITO electrode 43 formed on a surface facing the film substrate 42, of the film substrate 41; an ITO electrode 44 formed on a surface facing the film substrate 41, of the film substrate 42; a transparent conductor 50 which is formed in the vicinity of an outer edge of at least one surface facing the other one of the film substrates 41 and 42, and has an area smaller than those of ITO electrodes 43 and 44 and is made of the same material as the ITO electrodes; a plurality of columnar spacers 46 which are formed on one of ITO electrodes 43 and 44 and are bonded to the other of ITO electrodes or the transparent conductor 50 to form spaces between the film substrates 43 and 44; and a liquid crystal mixture 45 filled in the spaces. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  This case relates to a liquid crystal display element.

  In recent years, development of electronic paper has been actively promoted in various companies and universities. As for electronic paper, various application methods such as a sub display of a mobile terminal device and a display unit of an IC card have been proposed, starting with an electronic book. One display method of electronic paper is one that uses a liquid crystal composition in which a cholesteric phase is formed (cholesteric liquid crystal). This cholesteric liquid crystal is also called chiral nematic liquid crystal. A cholesteric liquid crystal is a liquid crystal in which molecules of a nematic liquid crystal form a spiral cholesteric phase by adding a relatively large amount (several tens of percent) of a chiral additive (chiral material) to the nematic liquid crystal. Cholesteric liquid crystals have excellent characteristics such as a semipermanent display retention characteristic (memory property), vivid color display characteristics, high contrast characteristics, and high resolution characteristics.

  A liquid crystal display element having a dot matrix structure including the cholesteric liquid crystal has a structure as shown in FIG. FIG. 9A is a plan view of a conventional liquid crystal display element 200, and FIG. 9B is a cross-sectional view of the conventional liquid crystal display element 200. As shown in FIGS. 9A and 9B, the liquid crystal display element 200 includes an upper substrate 204A, a lower electrode 204B, a peripheral sealing material 208, a sealing material 210, a bead spacer 212, and the like. And a liquid crystal material 214. The upper substrate 204A has a transparent electrode 202A, and the lower substrate 204B has a transparent electrode 202B. Although not shown, a film made of an alignment film material or the like is provided between the transparent electrodes 202A and 202B and the liquid crystal material 214. The peripheral sealing material 208 and the sealing material 210 serve to join the upper and lower substrates 204A and 204B and to enclose the liquid crystal material 214 in the space between the upper and lower substrates 204A and 204B.

  The bead spacer 212 has a role of keeping a gap between the upper and lower substrates 204A and 204B at a constant interval. As described in Patent Document 1, the bead spacers 212 are formed of granular glass spheres or resin spheres, and are randomly arranged on the lower substrate 204B by, for example, spraying onto the lower substrate 204B.

  On the other hand, columnar spacers are sometimes used instead of the bead spacers recently. This columnar spacer is often formed on a substrate through a photolithography process or the like. For this reason, the columnar spacer has the advantage that it can be arranged in the intended shape at the intended location.

  Furthermore, recently, as the upper and lower substrates constituting the liquid crystal display element, a thinner and flexible resin substrate has been developed instead of the glass substrate. However, when such a resin substrate is used, if the above-described bead spacer or columnar spacer is used as the spacer, the gap between the upper and lower substrates may not be maintained when the element is bent. . In this case, the liquid crystal may flow greatly and the display image may be disturbed, and a phenomenon such as failure to maintain the display image may occur in an element using cholesteric liquid crystal.

  As a countermeasure against the above phenomenon, it is conceivable to use an adhesive columnar spacer as described in Patent Document 2. By adopting the structure described in Patent Document 2, a bendable display element is realized in which the flow of liquid crystal and the gap variation during bending are suppressed.

Japanese Patent Laid-Open No. 5-165035 International Publication No. 2007/007394

  However, in the liquid crystal display element having the structure using the resin substrate and the adhesive columnar spacer as described above, the following phenomenon may occur when a temperature change in the surrounding environment occurs. That is, when the linear expansion coefficients of the members constituting the liquid crystal display element (particularly the liquid crystal, the substrate, and the columnar spacer) are greatly different, the internal volume of the space between the substrates and the volume of the liquid crystal material when the temperature change in the surrounding environment occurs. The difference increases. In this case, the adhesion part of the columnar spacer may be peeled off. In particular, when the peeled portion is in the display area for displaying an image, the display quality is lowered.

  As a means for solving this, a method of arranging a non-adhesive spacer different from the adhesive columnar spacer in an area outside the display area is also conceivable. However, in order to provide two types of spacers, it is necessary to form an adhesive columnar spacer on one of the upper and lower substrates and a non-adhesive columnar spacer on the other, and bond the two substrates together. This method takes time and costs.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a liquid crystal display element capable of suppressing a reduction in display quality due to a change in ambient temperature.

  The liquid crystal display element described in this specification is formed on a first substrate, a second substrate facing the first substrate, and a surface of the first substrate facing the second substrate. The second electrode formed on the surface of the second substrate facing the first substrate, and the other of at least one of the first and second substrates. A transparent conductor made of the same material as the first and second electrodes, formed in the vicinity of the outer edge on the surface facing the substrate, having a smaller area than the first and second electrodes, and the first It is formed on one of the electrode and the second electrode, and is adhered to the other electrode or the transparent conductor, and a space is provided between the first substrate and the second substrate. A plurality of spacers to be formed and a liquid crystal layer filled in the space are provided.

  The liquid crystal display element described in this specification has an effect of being able to suppress deterioration in display quality due to a change in ambient temperature.

It is a figure which shows schematically the structure of the liquid crystal display element which concerns on one Embodiment. 2A is a plan view showing the arrangement of the ITO electrodes 43, and FIG. 2B is a plan view showing the arrangement of the ITO electrodes 443. FIG. 3A is a diagram illustrating an alignment state of liquid crystal molecules when the liquid crystal mixture of the liquid crystal display element is in a planar state. FIG. 3B is a diagram showing the alignment state of the liquid crystal molecules when the liquid crystal mixture of the liquid crystal display element is in the focal conic state. FIG. 4A is a diagram showing the positional relationship between the transparent conductor, the ITO electrode, and the columnar spacer formed on the ITO electrode, and FIG. 4B is an adhesion diagram of the columnar spacer of FIG. It is a figure which shows a part. FIG. 5A is a diagram showing an arrangement relationship between the ITO electrodes and the columnar spacers formed on the ITO electrodes, and FIG. 5B is a diagram showing an adhesion portion of the columnar spacers of FIG. is there. FIG. 6A and FIG. 6B are diagrams for explaining the deformation state of the film substrate when the temperature of the surrounding environment changes. It is a figure which shows the example of arrangement | positioning of the columnar spacer which made arrangement | positioning density the smallest. It is a figure which shows the example of arrangement | positioning of a transparent conductor. FIG. 9A is a plan view of a conventional liquid crystal display element, and FIG. 9B is a cross-sectional view of the conventional liquid crystal display element.

  Hereinafter, an embodiment of a liquid crystal display element will be described in detail with reference to FIGS.

  FIG. 1 shows a schematic configuration of a liquid crystal display element 10 using a cholesteric liquid crystal capable of displaying an image in a memory without power. Note that the liquid crystal display element 10 in FIG. 1 is a liquid crystal display element that displays a monochrome image (here, green) as an example.

  As shown in FIG. 1, the liquid crystal display element 10 includes film substrates 41 and 42 as first and second substrates, ITO electrodes 43 and 44 as first and second electrodes, and liquid crystal as a liquid crystal layer. The mixture 45, the columnar spacer 46, the peripheral sealing material 47, and the light absorption layer 48 are included.

  The film substrates 41 and 42 are both translucent. As a material of the film substrates 41 and 42, for example, a film substrate such as PET (Polyethylene Terephthalate) or PC (Polycarbonate) is used.

  The ITO electrodes 43 and 44 are composed of a plurality of strip-like electrodes arranged in parallel. As shown in the plan view of FIG. 2A, the ITO electrodes 43 extend in the left-right direction on the paper surface of FIG. 2A and are arranged in the vertical direction of the paper surface. The ITO electrode 43 is disposed over almost the entire surface of the film substrate 41 so as to cover the entire display area DPA of the liquid crystal display element 10 set at the center of the film substrate 41. As shown in the plan view of FIG. 2B, the ITO electrodes 44 extend in the vertical direction on the paper surface of FIG. 2B and are arranged in the horizontal direction of the paper surface. The ITO electrode 44 is disposed over almost the entire surface of the film substrate 42 so as to cover the entire display area DPA. That is, the ITO electrode 43 and the ITO electrode 44 are arranged so as to cross each other at an angle of 90 °. Here, it is necessary to provide the ITO electrodes 43 and 44 by the number of pixels. For example, when the liquid crystal display device 100 is capable of displaying 320 × 240 dots QVGA, it is necessary to prepare 320 ITO electrodes 43 and 44 and 240 240 other electrodes. The material of the ITO electrodes 43 and 44 is Indium Tin Oxide (ITO: indium tin oxide). However, instead of this, an electrode using a transparent conductive film such as Indium Zic Oxide (IZO) may be employed.

  As shown in FIG. 2A, a plurality of transparent conductors 50 are provided on the film substrate 42 in addition to the ITO electrodes 43. The material of the transparent conductor 50 is the same material as the ITO electrodes 43 and 44. The details of the transparent conductor 50 will be described later.

An insulative thin film is formed on the ITO electrodes 43 and 44 (and the transparent conductor 50) (not shown). When this insulating thin film is thick, the drive voltage rises and it becomes difficult to control with a general-purpose STN driver. On the other hand, if an insulating thin film is not provided, a leakage current flows, resulting in an increase in power consumption. Since this insulating thin film has a relative dielectric constant of around 5 and lower than that of liquid crystal, the thickness of the insulating thin film is generally about 0.3 μm or less. As the insulating thin film, a SiO ₂ thin film or an organic film such as a known polyimide resin or acrylic resin can be used as the orientation stabilizing film.

  Returning to FIG. 1, the liquid crystal mixture 45 is a cholesteric liquid crystal composition that exhibits a cholesteric phase at room temperature. The liquid crystal mixture 45 can take a planar state, a focal conic state, or an intermediate state in which these are mixed by a voltage applied from an external power source through the ITO electrodes 43 and 44. The planar state is obtained by applying a predetermined high voltage to give a strong electric field to the liquid crystal and then suddenly reducing the electric field to zero. The focal conic state is obtained, for example, by applying a voltage lower than the predetermined high voltage to apply an electric field to the liquid crystal and then suddenly reducing the electric field to zero. In addition, in the intermediate state in which the planar state and the focal conic state are mixed, for example, after applying a voltage lower than the voltage at which the focal conic state is obtained to apply an electric field to the liquid crystal, the electric field is rapidly reduced to zero. Can be obtained.

  The liquid crystal mixture 45 is a cholesteric liquid crystal obtained by adding 10 to 40 wt% of a chiral material to a nematic liquid crystal mixture. The addition amount of the chiral material is a value when the total amount of the nematic liquid crystal component and the chiral material is 100 wt%. As the nematic liquid crystal, a conventionally known liquid crystal can be used, but the dielectric anisotropy (Δε) is preferably in the range of 15 to 35. If the dielectric anisotropy is 15 or more, the drive voltage is relatively low, but if it exceeds 35, the drive voltage itself is low but the specific resistance is small, and the power consumption at high temperature is particularly increased. The refractive index anisotropy (Δn) is preferably about 0.18 to 0.24. If it is smaller than this range, the reflectivity in the planar state will be low, and if it is larger than this range, the scattering reflection in the focal conic state will increase, and this will also increase the viscosity and decrease the response speed. Become.

  The columnar spacers 46 are for maintaining a uniform gap between the pair of film substrates 41 and 42, and are provided on the film substrate 42 (on the ITO substrate 44) at regular intervals. The columnar spacer 46 is, for example, a photoresist patterned on the ITO electrode 44 through a photolithography process and baked at 150 ° C. for about 120 minutes. The gap formed by the columnar spacers 46 is preferably in the range of 3 to 6 μm, for example. This is because when the gap is smaller than this range, the reflectivity decreases and the display becomes dark, and when the gap is large, the drive voltage rises and it becomes difficult to drive with general-purpose components. As the columnar spacer 46, a negative columnar spacer (the material is an acrylic resist, NCS-106 or NCS-506) is used. The columnar spacer 46 exhibits an adhesive force by reducing the crosslink density of the polymer.

  The peripheral sealing material 47 is for enclosing the liquid crystal mixture 45 between the film substrates 41 and 42. An epoxy sealant can be used as the peripheral seal material 47. The peripheral sealing material 47 is continuously provided along the outer edge portions of the film substrates 41 and 42, and in some of them, the liquid crystal mixture 45 is sealed in the space between the film substrates 41 and 42. An opening is provided. This opening is sealed with a sealing material after the liquid crystal mixture 45 is sealed.

  The light absorption layer 48 is provided on the back surface (the paper surface of FIG. 1) of the film substrate 42 located on the opposite side (the lower surface of the paper surface in FIG. 1) of the liquid crystal display element 10 to the side on which light is incident (the upper surface in FIG. The lower surface is provided on the side.

  Next, the display principle of the cholesteric liquid crystal will be described based on FIGS. 3 (a) and 3 (b). FIG. 3A shows the alignment state of the liquid crystal molecules 36 when the liquid crystal mixture 45 of the liquid crystal display element 10 is in the planar state. FIG. 3B shows the alignment state of the liquid crystal molecules 36 when the liquid crystal mixture 45 of the liquid crystal display element 10 is in the focal conic state.

  As shown in FIG. 3A, the liquid crystal molecules 36 in the planar state are sequentially rotated in the thickness direction to form a spiral structure, and the spiral axis of the spiral structure is substantially perpendicular to the substrate surface. In the planar state, incident light L having a predetermined wavelength corresponding to the helical pitch of the liquid crystal molecules is selectively reflected by the liquid crystal layer.

  In this case, if the average refractive index of the liquid crystal layer is n and the helical pitch is p, the wavelength λ at which reflection is maximum can be expressed by the product of n and p. Therefore, in order to selectively reflect light (for example, light in a predetermined wavelength band with a center wavelength of 550 nm) in the planar state by the liquid crystal mixture 45, the average refractive index n and the helical pitch p so that λ becomes the wavelength 550 nm. It is necessary to decide. The average refractive index n can be adjusted by selecting a liquid crystal material and a chiral material, and the helical pitch p can be adjusted by adjusting the content of the chiral material.

  On the other hand, as shown in FIG. 3B, the liquid crystal molecules 36 in the focal conic state are sequentially rotated in the in-plane direction of the substrate to form a spiral structure, and the spiral axis is substantially parallel to the substrate surface. In this case, the liquid crystal display element 10 loses the selectivity of the reflection wavelength and transmits most of the incident light L. Since the light transmitted through the liquid crystal mixture 45 is absorbed by the light absorption layer 48 shown in FIG. 1, dark display can be realized.

  Next, the above-described transparent conductor 50 provided on the film substrate 42 will be described in detail.

  FIG. 4A shows the positional relationship between the transparent conductor 50, the ITO electrode 44, and the columnar spacers 46 formed on the ITO electrode 44. As shown in FIG. 4A, the transparent conductor 50 has a substantially square plate shape, and a plurality of transparent conductors 50 are arranged at predetermined intervals in the two-dimensional direction. The transparent conductor 50 is in a state facing the ITO electrode 44. These transparent conductors 50 are in contact with the upper surfaces of the columnar spacers 46 in the vicinity of the respective corners. That is, as shown in FIG. 4A, four transparent conductors 50 are in contact with one columnar spacer 46.

  Here, in the present embodiment, as described above, a negative and adhesive columnar spacer is used as the columnar spacer 46. Therefore, the softened portion of the adhesion surface (upper surface in FIG. 4A) of the columnar spacer 46 is smaller than the conventionally used spacer. Therefore, as described above, when the upper surface of the columnar spacer 46 and the four transparent conductors 50 are in contact with each other, a step corresponding to the thickness is formed in the gap between the transparent conductors 50. The portion is not in contact with the columnar spacer 46. That is, the contact portion of the columnar spacer 46 with the transparent conductor 50 is only the portion that overlaps the transparent conductor 50, specifically, only the portion indicated by hatching in FIG.

  FIG. 5A shows an arrangement relationship of the ITO electrode 43, the ITO electrode 44, and the columnar spacers 46 formed on the ITO electrode 44 in the display area DPA. As shown in FIG. 5A, the columnar spacer 46 is sandwiched between one ITO electrode 43 and one ITO electrode 44 in the display area DPA. Therefore, the upper surface (adhesion surface) of the columnar spacer 46 and the ITO electrode 43 are bonded to the entire upper surface of the columnar spacer 46, that is, a portion shown by hatching in FIG.

  As described above, in the present embodiment, the area of the bonded portion is controlled by controlling the presence or absence of a gap between the members (transparent conductor 50) in contact with the upper surface of the columnar spacer 46 (FIG. 4B). FIG. 5B). Thereby, even if all the columnar spacers 46 used in the liquid crystal display element 10 have the same shape, the adhesive strength per unit area can be controlled according to the arrangement position of the columnar spacers 46. In the present embodiment, since the transparent conductor 50 is disposed outside the display area DPA as described above, only the adhesive force of a part other than the display area DPA can be reduced.

  For example, when the temperature of the surrounding environment changes, the volume of the liquid crystal mixture 45 may increase with respect to the volume of the space between the film substrates 41 and 42. Even in such a case, in this embodiment, as schematically shown in FIGS. 6A and 6B, only the adhesion of the columnar spacers 46 other than the display area DPA can be released. That is, it is possible to set the peeling generation portion 52 (portion shown with hatching in FIG. 6B) in a portion other than the display area DPA. As a result, even when the temperature of the surrounding environment changes, it is possible to suppress a decrease in display quality of the display area DPA.

  Next, the dimension and arrangement of the columnar spacer 46 and the dimension and arrangement of the transparent conductor 50 will be described in detail.

  First, the limit of the size (definition) of the columnar spacer 46 will be described from the viewpoint of using acrylic resists NCS-106 and NCS-506 as the material of the columnar spacer 46. Factors affecting the definition of the columnar spacer 46 include the limit definition of a photomask currently used, an exposure gap indicating the degree of proximity between the resist and the photomask, and a film reduction rate during development. In particular, when the above material is used, the degree of proximity between the resist and the photomask may be reduced in order to avoid adhesion with the resist that is the material of the columnar spacer. For example, in the case of forming a columnar pattern having a thickness of about 5 μm as the columnar spacer 46, in consideration of the above factors affecting the definition, the limit of the definition that can actually be formed is that the diameter of the columnar shape is about 10 μm. It becomes the degree of definition.

  Next, the arrangement density of the columnar spacers 46 for preventing the film substrates 41 and 42 from contacting each other will be described. The greatest force that can be applied to the liquid crystal display element 10 is atmospheric pressure. Arrangement of the columnar spacers 46 so that the film substrates 41 and 42 (or between the ITO electrodes 43 and 44) do not come into contact when the force due to the atmospheric pressure is applied to the film substrates 41 and 42 as an evenly distributed load. Calculate the density. Then, the minimum arrangement density is set as the minimum arrangement density.

Here, when the diameter of the columnar columnar spacer 46 is 10 μm, which is the limit of definition as described above, the maximum bending moment is given by assuming that the distance between adjacent columnar spacers 46 is L and the atmospheric pressure is w. M _max is
^{_{M max = wL 2/8 ...}} (1)
It becomes.

The maximum deflection Y _{max at} this time is expressed as follows, where E is the Young's modulus and I _z is the second moment of section.
Y _max = 5/384 × wL ⁴ / EI _Z (2)
It becomes.

If the distance between the film substrates 41 and 42 is the same as the thickness 5 μm of the columnar spacer 46, the film substrates 41 and 42 come into contact when Y _max is 5 μm or more. For this reason, in calculation, the value of the distance L between adjacent columnar spacers 46 such that Y _max is 5 μm is the maximum interval between the columnar spacers 46. Specifically, when resin-based materials are used as the film substrates 41 and 42, the film substrates 41 and 42 come into contact with each other when the interval between the columnar spacers 46 having a diameter of 10 μm is set to about 200 μm or more according to the formula (2). become.

  Therefore, in this embodiment, the arrangement of the columnar spacers 46 that achieves the minimum arrangement density is the arrangement shown in FIG. By adopting such an arrangement, it is possible to suppress the formation of a portion where no liquid crystal enters when the liquid crystal mixture is injected by the vacuum pumping method.

  Here, when the work of actually bonding the film substrates 41 and 42 is performed, there is a possibility that a positional deviation of the bonding may occur about ± 5 μm at the minimum value. Therefore, in order to ensure that the four transparent conductors 50 are brought into contact with the upper surface of the columnar spacer 46 having a diameter of 10 μm as shown in FIG. 4A, the transparent conductor 50 is formed on the entire surface outside the display area DPA. It is desirable to arrange them continuously. That is, it is considered that the distance between the transparent conductors 50 is 5 μm, which is half the diameter of the columnar spacers 46 so that the gaps between the transparent conductors 50 are located at the positions where the columnar spacers 46 are arranged.

  From the above viewpoint, in this embodiment, as shown in FIG. 8, the transparent conductor 50 disposed outside the display area DPA is set to 5 μm square, and the interval between the transparent conductors 50 is set to 5 μm.

  As described above in detail, according to the present embodiment, the ITO electrodes 43 and 44 are formed on the opposing surfaces of the two opposing film substrates 41 and 42, respectively, and the ITO substrate 43 is formed in the vicinity of the outer edge of the film substrate 42. A transparent conductor 50 having a smaller area than the electrodes 43 and 44 and the same material as the ITO electrode is formed. A plurality of columnar spacers 46 are formed on the ITO electrode 44 and bonded to the ITO electrode 43 or the transparent conductor 50 so that a space filled with the liquid crystal mixture 45 is provided between the film substrates 41 and 42. Form. Therefore, the adhesion area of the columnar spacer 46 disposed between the ITO electrode 44 and the transparent conductor 50 to the transparent conductor 50 is set to the ITO electrode 44 of the columnar spacer 46 disposed between the ITO electrodes 43 and 44. It can be controlled to be smaller than the adhesion area. Thereby, even if the temperature of the surrounding environment changes and the volume of the liquid crystal mixture 45 increases with respect to the volume of the space between the film substrates 41 and 42, the columnar spacer 46 and the transparent conductor 50 are bonded. It is possible to make it easy to peel only the part that is present. Thereby, the part (peeling generation | occurrence | production part 52) from which the adhesion part of the columnar spacer 46 peels can be concentrated on a part. Therefore, by setting the peeling generation part 52 at a position where the influence on the display quality is small, it is possible to suppress the deterioration of the display quality of the liquid crystal display element 10 due to the temperature. Moreover, since the material of the transparent conductor 50 is the same as that of the ITO electrode, the transparent conductor 50 and the ITO electrode can be patterned simultaneously.

  Here, as in the conventional case, when an adhesive material that is cured by heat is used, there is often a temperature range that softens immediately before bonding. For this reason, even if the transparent conductor 50 is used as in the present embodiment, the columnar spacer 46 may be deformed along the step, and the adhesion area may not be controlled. However, as in this embodiment, by using an acrylic resist as the material of the columnar spacer 46, it is possible to prevent the bonded portion of the columnar spacer 46 from being deformed along the step. Thereby, it is possible to appropriately control the bonding area.

  Moreover, as a method for partially controlling the adhesive force per unit area of the film substrates 41 and 42, a method of reducing the diameter of the column of the columnar spacer to be arranged, a method of reducing the arrangement density, and the like are also conceivable. However, reducing the diameter of the cylinder has a problem in accuracy, and if the arrangement density is too low, the density as a spacer is insufficient and the film substrates 41 and 42 may be in contact with each other. Therefore, as in the present embodiment, the design and manufacture of the columnar spacer 46 can be easily performed by changing the area and the arrangement pitch of the members that contact the columnar spacer 46, that is, the ITO electrode 43 and the transparent conductor 50. Can do.

  In addition, according to the present embodiment, since the region where the transparent conductor 50 is formed is a region other than the display region DPA, it is possible to effectively suppress deterioration in display quality due to the influence of the ambient temperature.

  In addition, according to the present embodiment, even if the plurality of columnar spacers 46 have the same shape, the bonding area can be controlled, so that the manufacture of the columnar spacers 46 can be simplified.

  In the above embodiment, the case where the columnar spacer 46 is formed on the ITO electrode 44 has been described. However, the present invention is not limited to this, and the columnar spacer 46 may be formed on the ITO electrode 43 side.

  Moreover, although the said embodiment demonstrated the case where the transparent conductor 50 was formed on the film board | substrate 41, you may form not only in this but on the film board | substrate 42 side. Moreover, you may form in both the film substrates 41 and 42. FIG. Further, the transparent conductor 50 may be provided at two or more locations.

  In the above embodiment, as shown in FIGS. 4A and 5A, the case where the columnar spacers 46 are arranged in a single row on one ITO electrode 44 has been described. It is not something that can be done. Of course, the columnar spacers 46 may be arranged in a plurality of rows on one electrode. Moreover, in the said embodiment, although many transparent conductors 50 of the same shape are arrange | positioned at equal intervals, it is not restricted to this. The transparent conductors 50 do not necessarily have the same shape as long as the area is smaller than that of the ITO electrode, and the transparent conductors 50 need not be arranged at equal intervals.

  In the above embodiment, the case where the present invention is applied to a cholesteric liquid crystal has been described. However, the present invention is not limited to this. The above-described embodiment can be applied to various display devices such as an electrophoretic method and an electronic powder fluid that can maintain display under no power.

  Moreover, although the said embodiment demonstrated the case where the liquid crystal display element 10 can perform only monochrome display, it is not restricted to this. For example, color display may be realized by overlapping the liquid crystal display elements 10 capable of displaying green, blue, and red. The monochrome display may be a color other than green.

  Moreover, although the said embodiment demonstrated the case where the liquid crystal display element 10 was a reflection type liquid crystal display element, it is not restricted to this. A transmissive liquid crystal display element may be realized by changing the light absorption layer 48 of the liquid crystal display element 10 of the above embodiment to a light source.

  The above-described embodiment is an example of a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

10 Liquid crystal display element 41 Film substrate (first substrate)
42 Film substrate (second substrate)
43 ITO electrode (first electrode)
44 ITO electrode (second electrode)
45 Liquid crystal mixture (liquid crystal layer)
46 Columnar spacer (spacer)
50 Transparent conductor

Claims (6)

A first substrate;
A second substrate facing the first substrate;
A first electrode formed on a surface of the first substrate facing the second substrate;
A second electrode formed on a surface of the second substrate facing the first substrate;
At least one of the first and second substrates is formed in the vicinity of the outer edge portion on the surface facing the other substrate, and has a smaller area than the first and second electrodes, and the first and second substrates. A transparent conductor of the same material as the electrode of
It is formed on one of the first electrode and the second electrode, and is adhered to either the other electrode or the transparent conductor, and the first substrate and the second substrate A plurality of spacers forming a space therebetween;
And a liquid crystal layer filled in the space.   The liquid crystal display element according to claim 1, wherein the region where the transparent conductor is formed is a region not used for display.   3. The liquid crystal display element according to claim 1, wherein an adhesion area of a spacer adhered to the transparent conductor is smaller than an adhesion area of a spacer adhered to the other electrode.   The liquid crystal display element according to claim 1, wherein the plurality of spacers have the same shape.   The liquid crystal display element according to claim 1, wherein the plurality of spacers are formed at equal intervals.   The liquid crystal display element according to claim 1, wherein the liquid crystal layer is a chiral nematic liquid crystal.

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