JP2007047343A - Liquid crystal display element and its manufacturing method, and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display element whose mass-productivity can be improved. <P>SOLUTION: When the liquid crystal display element having both an alignment film containing silicon oxide and vertically aligned liquid crystal 40 is manufactured, a plurality injection ports 52 are provided to a sealing material 50 and then the vertically aligned liquid crystal 40 is injected into a space P through the plurality of injection ports 52 by using a differential pressure injecting method. Even when the interval (cell gap) between a silicon driving element substrate 10 and a transparent electrode substrate 20 becomes temporarily narrow under the influence of stress due to surface tension and inner/outer differential pressure during the stage of injecting the vertically aligned liquid crystal 40, the quantity of narrowing of the cell gap is less than that when a single injection port is provided, so the time needed to put the cell gap back into its initial state becomes shorter. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid crystal display element used for displaying an image using the alignment characteristics of vertically aligned liquid crystal, a manufacturing method thereof, and a liquid crystal display device that displays an image using a liquid crystal display element.

  In recent years, with the increasing demand for higher definition, smaller size, and higher brightness of projection displays, reflective devices have been put to practical use as display devices. In this reflection type device, high light utilization efficiency can be realized together with high definition and miniaturization.

  As this reflection type device, an active reflection type liquid crystal display element having a configuration in which a liquid crystal is filled between a silicon driving element substrate and a transparent electrode substrate via an alignment film and a sealing material is known. A silicon driving element substrate is a silicon substrate provided with a driving element for circuit driving, a reflective electrode for light reflection (so-called pixel electrode), etc., and a transparent electrode substrate is provided with a transparent electrode or the like on a transparent substrate. It is a thing. The alignment film is for aligning liquid crystal molecules in a predetermined alignment state.

  In this reflective liquid crystal display element, when a voltage is applied between the pixel electrode and the transparent electrode, the alignment state of the liquid crystal molecules changes according to the potential difference between the two electrodes, and thus light is modulated. Thereby, since a gradation image is reproduced, an image is displayed.

  Among these reflective liquid crystal display elements, those using vertical alignment liquid crystals (so-called vertical alignment liquid crystals) are particularly noted as being capable of improving display performance due to their high contrast and fast response speed. ing. This “vertical alignment liquid crystal” means negative dielectric anisotropy, that is, dielectric constant ε (‖) in a direction parallel to the major axis of liquid crystal molecules and dielectric constant ε (⊥) in a direction perpendicular to the major axis. Is a liquid crystal having a property that the difference δε (= ε (‖) −ε (⊥)) is negative.

  When this vertically aligned liquid crystal is used, since the liquid crystal molecules are aligned perpendicularly to the substrate surface of the silicon driving element substrate when the applied voltage is zero, a so-called normally black mode display state is obtained, On the other hand, when a voltage is applied, the liquid crystal molecules are tilted in the plane of the substrate, so that the light transmittance changes. In this case, in particular, if the tilt direction of the liquid crystal molecules is not uniform during tilting, unevenness of light and darkness will occur. Therefore, in order to eliminate the unevenness of light and darkness, a state in which a slight angle (pretilt angle) is tilted in advance in a certain direction. It is necessary to align the liquid crystal molecules.

  In general, in a liquid crystal display element, a silicon driving element substrate and a transparent electrode substrate are supported and fixed with a frame-type sealing material that defines a display area interposed therebetween, and both substrates use predetermined particles (referred to as spacers). (Cell gap). Examples of the spacer include a seal spacer arranged around the display area and a cell spacer arranged in the display area. In general, the seal spacer is often embedded in a seal material. In the manufacturing process of the liquid crystal display element, the silicon drive element substrate and the transparent electrode substrate are pressurized with the sealing material and the spacer interposed therebetween, so that the cell gap is determined to be a predetermined value based on the particle size of the spacer. After that, liquid crystal is injected through an injection port provided in the sealing material. As a method for injecting the liquid crystal, a vacuum injection method (differential pressure injection method) using a capillary phenomenon and an internal / external differential pressure is generally used.

  However, in the projection display, an image is enlarged and projected using a small reflection type device, and if cell spacers are arranged in the display area, a problem occurs in display performance. Specifically, since the alignment state of the liquid crystal molecules is disturbed around the cell spacer, the contrast increases due to light leakage, or the cell spacer itself is projected on the screen, so that a shadow appears in the image. End up. For these reasons, a projection display aiming at high image quality employs a method in which no spacer is arranged in the display area (so-called spacerless method). In particular, in a reflective liquid crystal display element using vertically aligned liquid crystal, it is desirable to adopt a spacerless system as it is used in high image quality applications.

As for the liquid crystal injection method, several techniques are already known. Specifically, a technique for shortening the injection time by injecting liquid crystal through a plurality of injection ports has been proposed (see, for example, Patent Documents 1 and 2). In addition, a technique for eliminating injection unevenness by providing a protrusion at the injection port has been proposed (see, for example, Patent Document 3).
Japanese Patent Publication No. 07-092572 JP 2002-318388 A JP 2001-183683 A

  By the way, in order to improve the mass productivity of the projection display, it is necessary to shorten the time required for the manufacturing process as much as possible. However, in the manufacturing process of the reflective liquid crystal display element using the vertically aligned liquid crystal, the spacerless system (the cell spacer for adjusting the cell gap is not disposed in the display area) is used, so that the liquid crystal is injected vertically. A problem peculiar to the alignment liquid crystal arises. Specifically, since the silicon driving element substrate and the transparent electrode substrate are bent by the influence of the stress (surface tension) of the liquid crystal itself and the internal / external differential pressure, the cell gap is unintentionally narrowed. This bending phenomenon is an inherent phenomenon that occurs when an alignment film containing silicon oxide and a vertical alignment liquid crystal are combined, and is caused by insufficient wettability of the vertical alignment liquid crystal with respect to that type of alignment film. Arise. When this bending phenomenon occurs, it takes a long time for the cell gap to recover due to the relaxation of the bending of both substrates, making it difficult to improve the mass productivity of the projection display. In particular, since the degree of bending becomes more prominent as the display size increases, mass productivity is significantly reduced.

  The present invention has been made in view of such problems, and an object thereof is to provide a liquid crystal display element capable of improving mass productivity, a manufacturing method thereof, and a liquid crystal display device.

  A liquid crystal display element according to the present invention is provided so as to cover a silicon driving element substrate and a transparent electrode substrate that are arranged to face each other, and surfaces of the silicon driving element substrate and the transparent electrode substrate that face each other. An alignment film including a sealing material provided between the silicon driving element substrate and the transparent electrode substrate so as to demarcate a display region and having a plurality of injection holes for liquid crystal injection; and surrounded by the alignment film and the sealing material And a vertically aligned liquid crystal filled in the space.

  A method of manufacturing a liquid crystal display element according to the present invention includes a silicon driving element in which an alignment film including silicon oxide is provided so as to cover surfaces facing each other with a sealing material having a plurality of injection holes for liquid crystal injection interposed therebetween. The substrate and the transparent electrode substrate are arranged opposite to each other, thereby forming a space so as to be surrounded by the alignment film and the sealing material, and using a differential pressure injection method, the space is perpendicular to the space through a plurality of injection ports. And a step of injecting alignment liquid crystal.

  A liquid crystal display device according to the present invention displays an image using light modulated by a liquid crystal display element. The liquid crystal display element includes a silicon driving element substrate and a transparent electrode substrate, which are arranged to face each other, and silicon. Provided to cover the mutually facing surfaces of the drive element substrate and the transparent electrode substrate, and to provide a display region between the alignment film containing silicon oxide and the silicon drive element substrate and the transparent electrode substrate A sealing material having a plurality of injection holes for injecting liquid crystal, and vertically aligned liquid crystal filled in a space surrounded by the alignment film and the sealing material.

  In the liquid crystal display element or the manufacturing method thereof or the liquid crystal display device according to the present invention, when manufacturing a liquid crystal display element having both an alignment film containing silicon oxide and a vertical alignment liquid crystal, a plurality of injection holes are provided in the sealing material. By being provided, the vertically aligned liquid crystal is injected into the space through the plurality of injection ports using the differential pressure injection method. In this case, the gap (cell gap) between the silicon driving element substrate and the transparent electrode substrate is temporarily affected by the stress caused by the surface tension and the internal / external differential pressure during the vertical alignment liquid crystal injection process. Even if the gap is narrowed, the amount of narrowing of the cell gap is reduced compared to the case where a single injection port is provided, and the time required to restore the cell gap to the initial state is also shortened.

  According to the liquid crystal display element or the manufacturing method thereof or the liquid crystal display device according to the present invention, by providing a plurality of injection holes in the sealing material, a vertically aligned liquid crystal is formed in the space through the plurality of injection holes using the differential pressure injection method. Therefore, the cell gap is recovered in a short time in the liquid crystal injection process. Therefore, mass productivity can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  First, with reference to FIGS. 1-3, the structure of the liquid crystal display element mounted in the liquid crystal display device which concerns on one embodiment of this invention is demonstrated. 1 to 3 show a configuration of a liquid crystal display element, FIG. 1 shows a detailed sectional configuration, FIG. 2 schematically shows a planar configuration, and FIG. 3 schematically shows a sectional configuration. FIG. 3 shows a cross section taken along line III-III shown in FIG.

  As shown in FIGS. 1 to 3, the liquid crystal display element includes a silicon driving element substrate 10 and a transparent electrode substrate 20 that are arranged to face each other, and each of the silicon driving element substrate 10 and the transparent electrode substrate 20. A plurality of layers for injecting liquid crystal are provided so as to cover the opposing surfaces and are provided so as to demarcate an alignment film 30 containing silicon oxide and a display region 60 between the silicon driving element substrate 10 and the transparent electrode substrate 20. A sealing material 50 having an injection port 52, a vertically aligned liquid crystal 40 filled in a liquid crystal filling space P surrounded by the alignment film 30 and the sealing material 50, the silicon driving element substrate 10, and the transparent electrode substrate 20. And a plurality of spacers 51 provided therebetween.

  The silicon driving element substrate 10 mainly controls the alignment state of the vertically aligned liquid crystal 40 by driving the vertically aligned liquid crystal 40. The silicon drive element substrate 10 has a configuration in which a pixel electrode 13 is provided on one surface of a silicon substrate (single crystal silicon substrate) 11 on which a drive circuit including a drive element 12 is formed. 2 and 3 show the case where the planar size of the silicon driving element substrate 10 is larger than the planar size of the transparent electrode substrate 20, but the present invention is not necessarily limited to this, and the planar surfaces of both substrates are not limited thereto. The size can be set freely. For example, the planar size of the silicon driving element substrate 10 may match the planar size of the transparent electrode substrate 20.

  The drive element 12 constitutes a drive circuit for driving the vertical alignment liquid crystal 40. The drive element 12 includes, for example, a CMOS (Complementary Metal Oxide Semiconductor) type or NMOS (Negative polarity Metal Oxide Semiconductor) type transistor 121 and a capacitor (auxiliary capacitor) 122, and constitutes an active type drive circuit. ing.

  The pixel electrode 13 is one electrode for applying a voltage to the vertical alignment liquid crystal 40. The pixel electrodes 13 are divided and arranged in a plural number so as to form a matrix arrangement pattern, and potentials are supplied independently. Here, the pixel electrode 13 is, for example, a reflective electrode having light reflectivity. The liquid crystal display element provided with this reflective electrode is a so-called reflective liquid crystal display element. The pixel electrode 13 is made of, for example, a metal having high light reflectivity such as aluminum (Al) or silver (Ag). Note that the pixel electrode 13 may be covered with a reflective layer having a multilayer film structure such as a dielectric mirror so that the reflectance is increased, or an oxide or an oxide or the like so as to be protected from the outside. It may be covered with a protective layer such as nitride.

  The transparent electrode substrate 20 mainly transmits light incident from the outside of the liquid crystal display element (incident light L1) and light emitted to the outside by being modulated in the liquid crystal display element (emitted light L2). It is. The transparent electrode substrate 20 has a configuration in which a transparent electrode 22 is provided on one surface of the transparent substrate 21.

  The transparent substrate 21 is made of, for example, a transparent (light transmissive) material such as glass.

  The transparent electrode 22 is the other electrode for applying a voltage to the vertically aligned liquid crystal 40. The transparent electrode 22 extends so as to continuously pass through a region facing each pixel electrode 13, and is supplied with a common potential. The transparent electrode 22 is made of a transparent electrode material such as indium tin oxide (ITO).

  The alignment film 30 aligns the vertically aligned liquid crystal 40 so as to be in a predetermined alignment state. The alignment film 30 covers the pixel electrode 13 and the surrounding silicon substrate 11 in the silicon driving element substrate 10, and covers the transparent electrode 22 in the transparent electrode substrate 20.

  The vertical alignment liquid crystal 40 modulates the incident light L <b> 1 by changing the alignment state according to voltage application to the pixel electrode 13 and the transparent electrode 22. In this vertically aligned liquid crystal 40, when the applied voltage is zero, the liquid crystal molecules are aligned perpendicular to the substrate surface of the silicon substrate 11 (so-called normally black mode), while when the voltage is applied, the liquid crystal molecules are aligned. Inclination is oriented to the substrate surface. In particular, in the vertically aligned liquid crystal 40, the liquid crystal molecules are aligned in a state where the pretilt angle is inclined in a certain direction when the applied voltage is zero. This constant direction is, for example, a diagonal direction (= about 45 ° direction) on the upper surface of the pixel electrode 13. The pretilt angle is a slight angle, for example, about 1 ° to 5 °. The reason why this pretilt angle is a slight angle is that if the pretilt angle is too large, the vertical alignment of liquid crystal molecules deteriorates, that is, the contrast decreases due to an increase in black level.

  The sealing material 50 seals (seals) the space P provided between the silicon driving element substrate 10 and the transparent electrode substrate 20 in order to fill the vertically aligned liquid crystal 40 between them. . The sealing material 50 defines the display region 60 by having, for example, a substantially frame-shaped pattern structure. The display area 60 is an area where an image is displayed when the liquid crystal display element is mounted on the liquid crystal display device, and two sets of long sides and short sides (two long sides and two short sides) facing each other. ) Has a quadrangular planar shape defined by The diagonal size (the length of the diagonal line) S of the display area 60 is a display size (unit: inch) of a so-called liquid crystal display device. Here, for example, the diagonal size S is about 1 inch (= about 2.54 cm) or more. In FIG. 2 and FIG. 3, for example, a large portion (portion that defines the display region 60) recedes inward from the outer edge of the transparent electrode substrate 20 (most contour is smaller than the contour of the transparent electrode substrate 20). The case where the sealing material 50 is configured so that a part (part where the injection port 52 is provided) reaches the outer edge of the transparent electrode substrate 20 (a part extends to the outer edge of the transparent electrode substrate 20) is shown. .

  For example, when the display region 60 is defined by two sets of long sides and short sides facing each other, as shown in FIG. 2, the plurality of injection ports 52 is one long side of the sealing material 50. It is provided in the place corresponding to. In particular, when the long side dimension (width) is W, the short side dimension (height) is H, and the number of injection ports 52 is N, the number N of the injection ports 52 is expressed as N> W / H. Is done. FIG. 2 shows a case where two injection ports 52 (52A, 52B) are provided, for example. These two inlets 52A and 52B are, for example, arranged symmetrically (laterally symmetric) with respect to the center line C of the display region 60, and the plug 53 (in the state where the vertically aligned liquid crystal 40 is filled in the space P). It is blocked by two plugs 53A, 53B). The center line C is an imaginary line extending in parallel with the short side. The widths of the injection ports 52A and 52B can be set freely. Here, for example, the inlets 52A and 52B have the same width, specifically, about 2 mm. As will be described before confirmation, the plurality of injection ports 52 are provided only at locations corresponding to only one of the two long sides and short sides that define the display region 60. Are not provided at locations corresponding to one long side and two short sides (only an injection port for liquid crystal injection is provided, and no exhaust port for exhausting at the time of liquid crystal injection is provided).

  The spacer 51 is for defining a distance (so-called cell gap G) between the silicon driving element substrate 10 and the transparent electrode substrate 20. Strictly speaking, the cell gap G is an interval between the alignment films 30 at the center position of the display region 60, with reference to FIGS. 1 to 3. For example, as illustrated in FIG. 2, the spacer 51 is disposed around the display area 60, but is not disposed in the display area 60. Here, for example, the spacer 51 is embedded in the sealing material 50 along a frame-shaped pattern structure.

  Next, a detailed configuration of the liquid crystal display element will be described with reference to FIGS. FIG. 4 shows a circuit configuration of the liquid crystal display element shown in FIGS.

  The circuit portion of the liquid crystal display element includes a pixel drive circuit 61 that forms a plurality of pixels G in the display area 60, and a data driver 62 and a scan driver 63 provided around the display area 60. .

  The pixel drive circuit 61 is provided in a lower layer than the pixel electrode 13 and includes, for example, the transistor 121 and the capacitor 122 described above. In the pixel drive circuit 61, one pixel G is constituted by the pixel electrode 13 and the vertical alignment liquid crystal 40 together with the transistor 121 and the capacitor 122. That is, the display area 60 described above is an area configured to display an image by arranging a plurality of pixels G in a matrix. 4 shows the display region 60 including a plurality of pixels G, and separately shows the region corresponding to the four pixels G in the pixel drive circuit 61. As shown in FIG.

  In the pixel driving circuit 61, a plurality of data lines 71 are arranged in the row direction and a plurality of scanning lines 72 are arranged in the column direction, and the data lines 71 and the scanning lines 72 are at positions where they intersect each other. Pixel G is configured. In each transistor 121, the source electrode is connected to the data line 71, the gate electrode is connected to the scanning line 72, and the drain electrode is connected to the capacitor 122 and the pixel electrode 13. Each data line 71 is connected to a data driver 62, and an image signal is supplied from the data driver 62, and each scanning line 72 is connected to a scanning driver 63, and its scanning Scan signals are sequentially supplied from the driver 63.

  The data driver 62 and the scan driver 63 are for selecting a specific pixel G from the plurality of pixels G. An image signal D is input to the data driver 62 from the outside through a signal line 64.

  Next, the operation of the liquid crystal display element will be described with reference to FIGS.

  In this liquid crystal display element, when the incident light L1 is incident through the transparent electrode substrate 20, the incident light L1 passes through the vertical alignment liquid crystal 40 and is then reflected by the pixel electrode 13, whereby the emitted light L2 is reflected. And again through the transparent electrode substrate 20.

  At this time, when a voltage is applied between the pixel electrode 13 and the transparent electrode 22, the alignment state of the vertically aligned liquid crystal 40 changes according to the potential difference between the two electrodes, and thus the incident light L1 is modulated. Thereby, since the gradation image is reproduced based on the modulated outgoing light L2, a video is displayed.

  Note that a voltage is applied by the pixel drive circuit 61 when the alignment state of the vertically aligned liquid crystal 40 is changed. At this time, the data driver 62 supplies an image signal to the data line 71 based on the image signal D input through the signal line 64, and the scanning driver 63 sequentially supplies the scanning signal to the scanning line 72 at a predetermined timing. As a result, the alignment state of the vertically aligned liquid crystal 40 changes in the pixel G that is scanned according to the scanning signal supplied to the scanning line 72 and selected according to the image signal supplied to the data line 71.

  Next, with reference to FIGS. 1-8, the manufacturing method of the liquid crystal display element shown in FIGS. 1-4 is demonstrated. 5 to 8 are diagrams for explaining a method of manufacturing a liquid crystal display element. FIGS. 5 and 7 correspond to the planar configuration shown in FIG. 2, and FIGS. 6 and 8 are cross sections shown in FIG. Corresponds to the configuration. 6 shows a cross section taken along line VI-VI shown in FIG. 5, and FIG. 8 shows a cross section taken along line VIII-VIII shown in FIG. Hereinafter, the liquid crystal injection process in the manufacturing process of the liquid crystal display element will be referred to.

  When manufacturing the liquid crystal display element, first, as shown in FIGS. 5 and 6, the spacer 51 is sandwiched between the sealing material 50 having a plurality of injection ports 52 (two injection ports 52A and 52B), and The silicon driving element substrate 10 provided with the alignment film 30 containing silicon oxide so as to cover the opposing surfaces and the transparent electrode substrate 20 are disposed so as to face each other, thereby being surrounded by the alignment film 30 and the sealing material 50. Thus, a space P for filling the liquid crystal is formed. Thereby, the prototype (pre-product) of the liquid crystal display element is constructed. Note that the structural features of the pre-manufactured liquid crystal display element (hereinafter simply referred to as “pre-manufactured product”) have already been described in detail as the structural features of the liquid crystal display element, and thus the description thereof is omitted.

  Subsequently, as shown in FIGS. 7 and 8, the vertical alignment liquid crystal 40 is injected into the space P through the two injection ports 52 </ b> A and 52 </ b> B provided in the sealing material 50 using the differential pressure injection method. Specifically, by using the liquid crystal boat 110 provided with the liquid crystal pool 111, the two inlets 52A and 52B are brought into contact with the liquid crystal pool 111 in a reduced pressure atmosphere, and then the atmosphere is returned to normal pressure. The vertically aligned liquid crystal 40 is supplied to the space P by utilizing capillary action and internal / external differential pressure (pressure difference between the inside (space P) and the outside (external atmosphere) of the pre-product). As a result, as shown in FIG. 2, the vertically aligned liquid crystal 40 is filled in the space P. When the vertically aligned liquid crystal 40 is injected into the space P, as shown in FIG. 8, in the region not supported and fixed by the spacer 51 (display region 60), the stress caused by the surface tension and the internal / external differential pressure. The cell gap G is temporarily narrowed because the silicon driving element substrate 10 and the transparent electrode substrate 20 are bent so as to approach each other under the influence of the above. In addition, the pressure reduction conditions when using the differential pressure injection method can be freely set. If an example is given, it is about 100 Pa.

  Finally, after the pre-product is removed from the liquid crystal boat 110, the pre-product is allowed to stand naturally with the excess vertical alignment liquid crystal 40 remaining in the two inlets 52A and 52B. If this pre-product is left as it is, the influence of the stress due to the above-described surface tension and internal / external differential pressure is alleviated, and the excess vertical alignment liquid crystal 40 is additionally injected into the space P. As described above, the bending of the silicon driving element substrate 10 and the transparent electrode substrate 20 is eliminated, so that the cell gap G is restored to the initial state (the state before the vertical alignment liquid crystal 40 is injected into the space P). After that, as shown in FIG. 2, the vertically aligned liquid crystal 40 is sealed in the space P by sealing the injection ports 52A and 52B with plugs 53A and 53B, respectively. Thereby, since the liquid crystal injection process is completed, the liquid crystal display element shown in FIGS. 1 to 4 is completed.

  Next, the configuration of the liquid crystal display device according to the present embodiment will be described with reference to FIG. FIG. 9 schematically shows a configuration of a liquid crystal display device on which the liquid crystal display elements shown in FIGS. 1 to 4 are mounted.

  The liquid crystal display device according to the present embodiment is, for example, a liquid crystal projector using the liquid crystal display element shown in FIGS. 1 to 4 as a light valve. More specifically, the liquid crystal display device uses, for example, a liquid crystal light valve 90R for red, a liquid crystal light valve 90G for green, and a liquid crystal light valve 90B for blue as a liquid crystal light valve for three colors. This is a three-panel reflective liquid crystal projector that displays a full-color image on 100.

  The liquid crystal display device includes, for example, the above-described liquid crystal light valves 90R, 90G, and 90B, a light source 81, dichroic mirrors 82 and 83, a total reflection mirror 84, polarizing beam splitters 85, 86, and 87, and a combining prism 88. The projection lens 89 is also provided, and a series of these components is arranged along the optical axis F.

  The light source 81 generates white light L including red light LR, green light LG, and blue light LB, and is, for example, a halogen lamp, a metal halide lamp, or a xenon lamp.

  The dichroic mirror 82 separates the white light L into blue light LB and other mixed light (red light LR and green light LG). The dichroic mirror 82 is disposed between the light source 81 and the dichroic mirror 83 or the total reflection mirror 84, and guides the blue light LB to the total reflection mirror 84 and other mixed light to the dichroic mirror 83. ing.

  The dichroic mirror 83 separates the mixed light guided via the dichroic mirror 82 into red light LR and green light LG. The dichroic mirror 83 is disposed between the dichroic mirror 82 and the polarizing beam splitters 85 and 86, and guides the red light LR to the polarizing beam splitter 85 and guides the green light LG to the polarizing beam splitter 86. Yes.

  The total reflection mirror 84 reflects the blue light LB guided through the dichroic mirror 82. The total reflection mirror 84 is disposed between the dichroic mirror 82 and the polarization beam splitter 87, and guides the blue light LB to the polarization beam splitter 87.

  The polarization beam splitter 85 is disposed between the liquid crystal light valve 90R and the combining prism 88 on the optical path of the red light LR. The polarization beam splitter 85 has a polarization separation surface 85M, and separates the red light LR into two polarization components orthogonal to each other on the polarization separation surface 85M. The polarization separation surface 85M reflects one polarization component (for example, S polarization component) to guide it to the liquid crystal light valve 90R and transmits the other polarization component (for example, P polarization component). The polarization beam splitters 86 and 87 have the same function and configuration as the polarization beam splitter 85, except that each of the green light LG and the blue light LB is separated into two polarization components orthogonal to each other. In other words, the polarization beam splitter 86 is disposed between the liquid crystal light valve 90G and the combining prism 88 on the optical path of the green light LG, has the polarization separation surface 86M, and the polarization beam splitter 87 has the blue light LB. Is disposed between the liquid crystal light valve 90B and the combining prism 88 on the optical path, and has a polarization separation surface 87M.

  The liquid crystal light valve 90R modulates red light LR (for example, S polarization component) guided through the polarization beam splitter 85 by driving according to the drive voltage supplied based on the image signal. is there. The liquid crystal light valve 90R is disposed to face the polarizing beam splitter 85, and reflects the modulated light (modulated light) toward the polarizing beam splitter 85. The liquid crystal light valves 90G and 90B have the same function and configuration as the liquid crystal light valve 90R except that the light guided through the polarization beam splitters 86 and 87 is modulated. That is, the liquid crystal light valve 90G modulates the green light LG (for example, S polarization component) and then reflects the modulated light toward the polarization beam splitter 86. The liquid crystal light valve 90B After the blue light LB (for example, S polarization component) is modulated, the modulated light is reflected toward the modulation beam splitter 87.

  The combining prism 88 combines modulated light guided from the liquid crystal light valves 90R, 90G, and 90B via the polarization beam splitters 85, 86, and 87, respectively. The combining prism 88 is arranged so as to be surrounded from three directions by the polarization beam splitters 85, 86, and 87, and emits the combined light (combined light) toward the projection lens 89.

  The projection lens 89 displays an image by projecting the combined light emitted from the combining prism 88 onto the screen 100.

  In this liquid crystal display device, when white light L is generated from the light source 81, the white light L is separated into red light LR, green light LG, and blue light LB in the dichroic mirrors 82 and 83. The red light LR, the green light LG, and the blue light LB are separated into predetermined polarization components (for example, S polarization components) by the polarization beam splitters 85, 86, and 87, respectively, and then the liquid crystal light valves 90R, 90G, and 90B. Is finally synthesized by the synthesis prism 88. By projecting the combined light onto the screen 100 by the projection lens 89, a full-color image is displayed on the screen 100.

  In the liquid crystal display device, the liquid crystal display element, or the manufacturing method thereof according to the present embodiment, the liquid crystal display including the alignment film 30 containing silicon oxide and the vertical alignment liquid crystal 40 and the spacer 51 is not disposed in the display region 60. When manufacturing the element, by providing a plurality of injection ports 52 in the sealing material 50, the vertically aligned liquid crystal 40 is injected into the space P through the plurality of injection ports 52 using the differential pressure injection method. Mass productivity can be improved for the following reasons.

  10 to 13 are for explaining the configuration and procedure of a liquid crystal display element or a manufacturing method thereof as a comparative example related to the liquid crystal display element or the manufacturing method thereof according to the present embodiment. 3, and correspond to FIG. 7 and FIG. In the liquid crystal display element of this comparative example or the manufacturing method thereof, the sealing material 150 has a single inlet 152, the inlet 152 is closed by a plug 153, and the space P is passed through the single inlet 152. The liquid crystal display device according to the present embodiment or the manufacturing method thereof has the same configuration and procedure except that the vertical alignment liquid crystal 40 is injected into the liquid crystal display device.

  In the liquid crystal display element of the comparative example or the manufacturing method thereof, as shown in FIGS. 10 and 11, only the single inlet 152 is provided in the sealing material 150. When the vertical alignment liquid crystal 40 is injected into the space P through the injection port 152 using the injection method, the injection process takes a long time. Specifically, as shown in FIGS. 12 and 13, the influence of the stress caused by the surface tension and the internal / external differential pressure is remarkably increased, so that the silicon driving element substrate 10 and the transparent electrode substrate 20 are easily bent excessively. As a result, since the cell gap G tends to be excessively narrowed, the standing time required for restoring the cell gap G to the initial state becomes long. As a result, the proportion of the injection process in the time required for the entire manufacturing process of the liquid crystal display element is relatively increased, and thus the overall manufacturing efficiency is lowered, so that it is difficult to improve the mass productivity.

  On the other hand, in the liquid crystal display element according to the present embodiment or the manufacturing method thereof, as shown in FIG. 2 and FIG. 3, the sealing material 50 is provided with a plurality of inlets 52. In this manufacturing process, when the vertically aligned liquid crystal 40 is injected into the space P through each injection port 52 using the differential pressure injection method, the injection process does not require a long time. Specifically, as shown in FIGS. 7 and 8, the influence of the stress caused by the surface tension and the internal / external differential pressure is alleviated, so that the silicon driving element substrate 10 and the transparent electrode substrate 20 are difficult to bend excessively. As a result, the cell gap G is less likely to be excessively narrowed, so that the standing time required for restoring the cell gap G to the initial state is shortened. Therefore, since the ratio of the injection process in the time required for the entire manufacturing process of the liquid crystal display element becomes relatively small, the overall manufacturing efficiency is improved, so that the mass productivity can be improved.

  Here, the technical significance of the present invention will be described. That is, the present invention is characterized in that the sealing material 50 is provided with a plurality of injection ports 52 for liquid crystal injection, but simply referring to the viewpoint of “providing a plurality of injection ports for liquid crystal injection”, the above “ As described with reference to the prior art in the section “Background Art”, several techniques proposed in this respect are already known. However, in the present invention, providing a plurality of injection ports 52 in the sealing material 50 has a different technical significance from simply providing a plurality of injection ports when associated with the basic configuration and manufacturing process of the liquid crystal display element. have. Specifically, in the liquid crystal display element of the present invention, (1) the alignment film 30 containing silicon oxide is used to align the vertically aligned liquid crystal 40, and (2) the spacer 51 is arranged in the display region 60. (3) The differential pressure injection method is used to inject the vertically aligned liquid crystal 40 into the space P, and the conditions (1) to (3) are satisfied at the same time. In this case, providing the sealing material 50 with a plurality of inlets 52 has its own technical significance. This is because, when the conditions (1) to (3) are satisfied, as described above, the wettability of the vertical alignment liquid crystal 40 with respect to the alignment film 30 is insufficient, and the silicon driving element substrate 10 and The inherent phenomenon that the transparent electrode substrate 20 is easily bent occurs, and the above-described bending phenomenon becomes remarkable due to the adoption of the spacerless method and the differential pressure injection method. This is because the provision of the plurality of injection ports 52 at 50 provides an advantageous technical effect that the silicon driving element substrate 10 and the transparent electrode substrate 20 are less likely to be bent. This advantageous technical effect is particularly effective when the diagonal size S of the display area 60 is about 1 inch or more. Therefore, providing a plurality of injection ports 52 in the sealing material 50 in the present invention is fundamentally different from “providing a plurality of injection ports” when the conditions (1) to (3) are not satisfied. It is.

  In particular, in the present embodiment, as shown in FIG. 2, a plurality of injection ports 52 are provided at locations corresponding to one long side that defines the display region 60, so that it corresponds to one short side. Compared with the case where a plurality of injection ports 52 are provided at a location, the injection distance when the vertically aligned liquid crystal 40 is injected into the space P is shortened. The injection distance of the vertical alignment liquid crystal 40 is from the injection location (location where the injection port 52 is provided) of the sealing material 50 to the opposite location (location opposite to the location where the injection port 52 is provided). Is the distance. Specifically, in the case where a plurality of injection ports 52 are provided at locations corresponding to the long sides, the distance is equal to the height H. On the other hand, when the plurality of injection ports 52 are provided at locations corresponding to the short sides, A distance equal to the width W. Therefore, since the unevenness in filling is less likely to occur due to the movement distance of the vertically aligned liquid crystal 40 at the time of injection, the vertically aligned liquid crystal 40 can be uniformly filled in the space P.

  Further, in the present embodiment, as shown in FIG. 2, the plurality of injection ports 52 are arranged symmetrically with respect to the center line C of the display area 60, so the plurality of injection ports 52 are arranged asymmetrically. Unlike the case where the vertical alignment liquid crystal 40 is injected into the space P, the vertical alignment liquid crystal 40 is uniformly injected in the right and left regions of the center line C. Therefore, since the filling state of the vertical alignment liquid crystal 40 is made uniform in the right region and the left region as described above, filling unevenness is hardly generated. From this viewpoint, the vertical alignment liquid crystal 40 is uniformly filled in the space P. Can do.

  In the present embodiment, as shown in FIG. 2, the two inlets 52 </ b> A and 52 </ b> B are provided as the plurality of inlets 52 in the sealing material 50, but the present invention is not necessarily limited to this. The number of the inlets 52 can be freely set in two or more ranges.

  Next, examples relating to the present invention will be described.

  First, when the influence of the number of injection ports on the recovery state of the cell gap was examined, the result shown in FIG. 14 was obtained. FIG. 14 shows the recovery state of the cell gap, the horizontal axis indicates time T (time), and the vertical axis indicates cell gap G (−). This time T represents the passage of time during the manufacturing process of the liquid crystal display element, the time T = -2 hours to 0 hours indicates the time required for the liquid crystal injection process, and the time T = 0 hours to 15 hours is the liquid crystal. The standing time after the injection process is shown. The cell gap G is a value normalized with respect to the cell gap values at time T = −2 hours and 15 hours. The symbols (×, ○, Δ, □) shown in FIG. 14 represent the difference in the number of inlets, where x indicates 1, ○ indicates 2, △ indicates 3, and □ indicates 5. . When examining the recovery state of the cell gap, the diagonal size of the display region was 1.55 inches, the width of the injection port was 2 mm, and the pressure reduction condition of the differential pressure injection method was 100 Pa.

  As can be seen from the results shown in FIG. 14, the cell gap G is temporarily narrowed in the liquid crystal injection process (time T = −2 hours to 0 hour), regardless of the number of injection ports, and then the standing process (time). It recovered to the initial state (time T = -2 hours) at T = 0 to 15 hours). However, when the recovery time of the cell gap G is compared between the case where a plurality of injection ports are provided (◯, Δ, □) and the case where a single injection port is provided (×), the recovery time is simply In the case where a plurality of inlets are provided, the length is shorter than in the case where one inlet is provided. Specifically, when a single inlet is provided, the cell gap G recovered at time T = 15 hours, whereas when a plurality of inlets are provided, the cell gap G is timed. Recovery occurred at T = 6 hours, that is, the time required for recovery (leaving time) was shortened by 9 hours. When a plurality of injection ports were provided, no significant difference was found in the recovery time depending on the number of injection ports (2, 3, or 5). From this, it was confirmed that the time required to recover the cell gap can be shortened by providing a plurality of injection ports in the present invention.

  Here, before the confirmation, when the influence of the width of the injection port on the recovery state of the cell gap was examined in the case where a single injection port was provided, the result shown in FIG. 15 was obtained. FIG. 15 shows the recovery status of another cell gap, and corresponds to the recovery status shown in FIG. The symbols (◯, Δ) shown in FIG. 15 indicate the difference in the width of the injection port, where ○ indicates 2 mm and Δ indicates 6 mm. The conditions (diagonal size and decompression conditions) for examining the recovery state of the cell gap are the same as those described with reference to FIG.

  As can be seen from the results shown in FIG. 15, when a single injection port is provided (◯, Δ), the cell gap G recovers at time T = 15 hours regardless of the difference in the width of the injection port. did. This means that if only a single inlet is provided in the case of a diagonal size of 1.55 inches, the stress caused by the surface tension and the internal / external differential pressure is recovered rather than the width of the inlet by the recovery of the cell gap G. This greatly influences the situation, and simply increasing the width of the injection port does not improve the recovery state of the cell gap G. From this, it was confirmed that increasing the number is more effective than increasing the width of the injection port in order to shorten the time required for recovery of the cell gap.

  Further, when the influence of the diagonal size on the recovery state of the cell gap was examined with respect to the case where a single injection port was provided, the result shown in FIG. 16 was obtained. FIG. 16 shows still another recovery state of the cell gap, which corresponds to the recovery state shown in FIG. The symbols (◯, Δ) shown in FIG. 16 represent the difference in diagonal size, where ○ indicates 1.55 inches and Δ indicates 0.78 inches. The conditions (injection port width and decompression conditions) for examining the recovery state of the cell gap are the same as those described with reference to FIG.

  As can be seen from the results shown in FIG. 16, the time required for the recovery of the cell gap G is greater when the diagonal size is 1.55 inches (◯) than when the diagonal size is 0.78 inches (Δ). It became long. Specifically, when the diagonal size is 0.78 inches, the degree of narrowing of the cell gap G becomes relatively small, and the cell gap G recovered at time T = 5 hours, whereas When the angular size was 1.55 inches, the degree of narrowing of the cell gap G was relatively large, and the cell gap G recovered at time T = 15 hours. This means that when the diagonal size is larger than about 1 inch, the cell gap is difficult to recover. From this, it was confirmed that the recovery time of the cell gap can be effectively shortened by providing a plurality of injection ports when the diagonal size is larger than 1 inch.

  As described above, the liquid crystal display device, the liquid crystal display element, or the manufacturing method thereof according to the present invention has been described with reference to the embodiment or the example. However, the present invention is not limited to the aspect described in the above embodiment or example. As described above, when the alignment film containing silicon oxide and the vertical alignment liquid crystal are provided and the spacer is not disposed in the display region, a plurality of liquid crystal injection ports are provided in the sealing material, and the differential pressure injection method is used. As long as it is possible to improve the mass productivity by injecting vertically aligned liquid crystal through a plurality of injection ports, the configuration and procedure regarding the liquid crystal display device, the liquid crystal display element, or the manufacturing method thereof can be freely changed. .

  In the above embodiment or example, the liquid crystal display device, the liquid crystal display element, or the manufacturing method thereof according to the present invention is applied to the reflective liquid crystal display device or the liquid crystal display element. For example, the present invention can be applied to a transmissive liquid crystal display device or a liquid crystal display element. In these transmissive liquid crystal display devices or liquid crystal display elements, the pixel electrodes are made of a transparent electrode material such as ITO. Even in this case, the same effect as the above-described embodiment or example can be obtained.

  The liquid crystal display device, the liquid crystal display element, or the manufacturing method thereof according to the present invention can be applied to a projection display such as a reflective liquid crystal projector.

It is sectional drawing showing the detailed cross-sectional structure of the liquid crystal display element mounted in the liquid crystal display device which concerns on one embodiment of this invention. FIG. 2 is a plan view schematically illustrating a planar configuration of the liquid crystal display element illustrated in FIG. 1. It is sectional drawing which represents typically the cross-sectional structure corresponding to the plane structure shown in FIG. It is a figure showing the circuit structure of the liquid crystal display element shown in FIG. It is a top view for demonstrating the manufacturing method of the liquid crystal display element mounted in the liquid crystal display device which concerns on one embodiment of this invention. FIG. 6 is a cross-sectional view illustrating a cross-sectional configuration corresponding to the planar configuration illustrated in FIG. 5. It is a top view for demonstrating the process following FIG. FIG. 8 is a cross-sectional view illustrating a cross-sectional configuration corresponding to the planar configuration illustrated in FIG. 7. It is a figure which represents typically the structure of the liquid crystal display device which concerns on one embodiment of this invention. It is a top view showing the plane structure of the liquid crystal display element as a comparative example with respect to the liquid crystal display element mounted in the liquid crystal display device which concerns on one embodiment of this invention. It is sectional drawing showing the cross-sectional structure corresponding to the planar structure shown in FIG. It is a top view for demonstrating the manufacturing method of the liquid crystal display element as a comparative example with respect to the manufacturing method of the liquid crystal display element mounted in the liquid crystal display device which concerns on one embodiment of this invention. FIG. 13 is a cross-sectional view illustrating a cross-sectional configuration corresponding to the planar configuration illustrated in FIG. 12. It is a figure showing the recovery condition of a cell gap. It is a figure showing the recovery condition of another cell gap. It is a figure showing the recovery condition of another cell gap.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Silicon drive element substrate, 11 ... Silicon substrate, 12 ... Drive element, 13 ... Pixel electrode, 20 ... Transparent electrode substrate, 21 ... Transparent substrate, 22 ... Transparent electrode, 30 ... Alignment film, 40 ... Vertical alignment liquid crystal, 50 ... Sealing material, 51 ... Spacer, 52 (52A, 52B) ... Injection port, 53 (53A, 53B) ... Plug, 60 ... Display area, 61 ... Pixel drive circuit, 62 ... Data driver, 63 ... Scan driver, 64 ... Signal line 71 ... Data line 72 ... Scanning line 81 ... Light source 82,83 ... Dichroic mirror 84 ... Total reflection mirror 85,86,87 ... Polarizing beam splitter, 85M, 86M, 87M ... Polarization separation plane, 88 ... Synthetic prism, 89 ... Projection lens, 100 ... Screen, 110 ... Liquid crystal boat, 111 ... Liquid crystal pool, 121 ... Transistor, 122 ... Capacitor, C ... Core wire, D ... image signal, F ... optical axis, G ... cell gap, H ... height, L ... white light, L1 ... incident light, L2: emitted light, LB ... blue light, LG ... green light, LR ... Red light, P ... space, S ... diagonal size, W ... width.

Claims (11)

A silicon driving element substrate and a transparent electrode substrate disposed opposite to each other;
An alignment film that is provided so as to cover mutually facing surfaces of the silicon driving element substrate and the transparent electrode substrate, and includes silicon oxide;
A sealing material provided to demarcate a display region between the silicon driving element substrate and the transparent electrode substrate, and having a plurality of injection holes for liquid crystal injection;
And a vertical alignment liquid crystal filled in a space surrounded by the alignment film and the sealing material. The display area has a rectangular planar shape defined by two sets of long sides and short sides facing each other;
The liquid crystal display element according to claim 1, wherein the plurality of inlets are provided at locations corresponding to one long side of the sealing material. The number N of the inlets is represented by N> W / H, where W is the dimension of the long side, H is the dimension of the short side, and N is the number of the inlets. 2. A liquid crystal display element according to 2. The liquid crystal display element according to claim 1, wherein the plurality of inlets are arranged symmetrically with respect to a center line of the display region. And a plurality of spacers provided between the silicon driving element substrate and the transparent electrode substrate,
The liquid crystal display element according to claim 1, wherein the spacer is arranged around the display area, but is not arranged in the display area. The liquid crystal display element according to claim 2, wherein a diagonal size of the display area is 1 inch or more. The liquid crystal display element according to claim 1, wherein the liquid crystal display element is configured as a reflective liquid crystal display element. A silicon driving element substrate provided with an alignment film containing silicon oxide and a transparent electrode substrate are arranged opposite to each other with a sealing material having a plurality of injection holes for liquid crystal injection interposed therebetween so as to cover the surfaces facing each other. A step of configuring a space so as to be surrounded by the alignment film and the sealing material,
And a step of injecting vertically aligned liquid crystal into the space through the plurality of injection ports using a differential pressure injection method. A liquid crystal display device that displays an image using light modulated by a liquid crystal display element,
The liquid crystal display element is
A silicon driving element substrate and a transparent electrode substrate disposed opposite to each other;
An alignment film that is provided so as to cover mutually facing surfaces of the silicon driving element substrate and the transparent electrode substrate, and includes silicon oxide;
A sealing material provided to demarcate a display region between the silicon driving element substrate and the transparent electrode substrate, and having a plurality of injection holes for liquid crystal injection;
And a vertical alignment liquid crystal filled in a space surrounded by the alignment film and the sealing material. The liquid crystal display device according to claim 9, further comprising: a light source that generates light; and a projection lens that projects light modulated by the liquid crystal display element. The liquid crystal display element is a reflective liquid crystal display element further comprising a pixel electrode having light reflectivity,
The liquid crystal display device according to claim 10, wherein the liquid crystal display device is configured as a reflective liquid crystal display device.

Images