Liquid crystal device and electronic apparatus

Abstract

To prevent variations of a cell gap caused by stress when an adhesion part for preventing entry of water cures.SOLUTION: A liquid crystal device comprises: an element substrate 12 that has a terminal N electrically connected to an FPC substrate; an opposing substrate 15 that is bonded to the element substrate 12 with a sealing material 16 therebetween; and a liquid crystal layer 140 that is arranged between the element substrate 12 and the sealing material 16. The opposing substrate 15 has, in plan view, a projection 17 that projects toward the element substrate 12 on the outside of the sealing material 16 and on a side S on a terminal side of the element substrate 12. The liquid crystal device further has an adhesive 19 that bonds the element substrate 12 and a side face on a terminal side of the opposing substrate 15 to each other.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a liquid crystal device and an electronic device. [Background technology]

[0002] For example, in a liquid crystal device, an element substrate and an opposing substrate are bonded together with a sealant at a fixed gap, and a liquid crystal layer is sandwiched in the gap. In such a configuration, if moisture penetrates into the liquid crystal layer through the sealant, the liquid crystal layer will deteriorate. For this reason, a technique is known in which a moisture-curing filler is filled into the gap between the liquid crystal device and a frame that casing the liquid crystal device (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-220525 Summary of the Invention [Problem to be solved by the invention]

[0004] As such, in liquid crystal devices, it is important to prevent moisture from entering the liquid crystal layer. However, there is also the problem that the stress generated when the material used to prevent moisture from entering hardens can disrupt the gap between the substrates, the so-called cell gap. [Means for solving the problem]

[0005] In order to solve the above problem, a liquid crystal device according to one embodiment of the present disclosure comprises a first substrate having terminals electrically connected to a wiring substrate, a second substrate bonded to the first substrate via a sealing material, and a liquid crystal layer disposed between the first substrate and the second substrate, wherein the second substrate has a convex portion that protrudes toward the first substrate at least on the terminal-side edge of the first substrate, outside the sealing material in a planar view, and further has an adhesive portion that bonds the first substrate to the terminal-side side of the second substrate. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a perspective view showing a liquid crystal device according to a first embodiment. [Figure 2] FIG. 1 is a cross-sectional view of a liquid crystal device. [Figure 3] FIG. 2 is a plan view showing the arrangement of elements in a liquid crystal device. [Figure 4] FIG. 10 is a diagram showing variations in gap amount in the embodiment and a comparative example. [Figure 5] FIG. 10 is a cross-sectional view of a liquid crystal device according to a second embodiment. [Figure 6] FIG. 2 is a plan view showing the arrangement of elements in a liquid crystal device. [Figure 7] FIG. 10 is a perspective view showing a liquid crystal device according to a modified example. [Figure 8] FIG. 1 is a diagram showing an optical configuration of a projection display device to which a liquid crystal device according to an embodiment and the like is applied. [Figure 9] FIG. 10 is a cross-sectional view of a liquid crystal device according to a comparative example. [Figure 10] FIG. 10 is a plan view showing the arrangement of elements in a liquid crystal device according to a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, liquid crystal devices according to embodiments will be described with reference to the drawings. Note that in each drawing, the dimensions and scale of each part are appropriately different from those of the actual device. Furthermore, the embodiments described below are preferred specific examples, and therefore various technically preferable limitations are applied. However, the scope of the present disclosure is not limited to these embodiments unless otherwise specified in the following description to the effect that the present disclosure is limited.

[0008] FIG. 1 is a perspective view showing a transmissive liquid crystal device 10 according to a first embodiment. As shown in the figure, in the liquid crystal device 10, an element substrate 12 and a counter substrate 15 are bonded together. Both the element substrate 12 and the counter substrate 15 have a rectangular shape in a plan view. For convenience, the longitudinal direction of the rectangular shape is defined as the X direction, and the lateral direction is defined as the Y direction. Furthermore, the direction perpendicular to the XY plane and in which light enters the liquid crystal device 10 is defined as the Z direction. In this embodiment, light enters from the counter substrate 15 toward the element substrate 12. Note that a plan view refers to viewing the liquid crystal device 10 from the Z direction or from the direction opposite to the Z direction.

[0009] FIG. 2 is a cross-sectional view of the liquid crystal device 10 taken along the Y direction, and FIG. 3 is a plan view of the liquid crystal device 10. As shown in FIG. In the liquid crystal device 10, an element substrate 12 on which a pixel electrode 120 is provided and an opposing substrate 15 on which a common electrode 150 is provided are bonded together with a sealing material 16 so that the electrode forming surfaces face each other while maintaining a certain gap, and a liquid crystal layer 140 is sandwiched in this gap. In addition to the pixel electrodes 120, the element substrate 12 is also provided with scanning lines, data lines, transistors for switching between the data lines and the pixel electrodes 120, and driving circuits for driving the scanning lines and data lines, but these elements are not important and will not be described here.

[0010] Polarizing plates (not shown) are arranged on the entrance and exit sides of the liquid crystal device 10, and the transmittance of the liquid crystal element changes depending on the voltage applied by the pixel electrodes 120 and the common electrode 150. Therefore, a display image is generated in a display region A1 where the pixel electrodes 120 are arranged in a plan view.

[0011] The element substrate 12 and the counter substrate 15 have three sides aligned in a plan view, but one longitudinal side of the element substrate 11 protrudes in the Y direction from the side S of the counter substrate 15 in a plan view. For convenience, the surface of the element substrate 12 that protrudes from the counter substrate 15 and faces the counter substrate 15 is referred to as a protruding surface 121.

[0012] A plurality of terminals N are provided on the protruding surface 121 as shown in Fig. 3. One end of the FPC board 61 is connected to the plurality of terminals N as shown in Fig. 1. FPC is an abbreviation for Flexible Printed Circuits. The other end of the FPC board 61 is connected to a host device (not shown). The host device supplies data signals corresponding to the gradation levels of the pixels, control signals for controlling the drive circuits, and the like to the liquid crystal device 10 via the FPC board 61.

[0013] 2 or 3, in this embodiment, a frame-shaped convex portion 17 is provided on the surface of the counter substrate 15 facing the element substrate 12, outside the sealing material 16, in plan view. The convex portion 17 is formed of, for example, SiO2, and its thickness in the Y direction is approximately the same as the thickness (cell gap) of the liquid crystal layer 140. In plan view, the width A3 of the convex portion 17 in each of the X direction and the Y direction is approximately 1 to 2% of the length L of the element substrate 12 and the counter substrate 15 in the X direction. When viewed from above, the inside of the protrusion 17 is not in contact with the sealing material 16 , and the outside of the protrusion 17 is substantially flush with the side surface of the counter substrate 15 .

[0014] An adhesive 19 is applied to the side surfaces of three sides of the element substrate 12 and the counter substrate 15, and to the side surface of the side S of the counter substrate 15. In particular, on the side S of the counter substrate 15, the adhesive 19 is applied to the side surface of the counter substrate 15, the convex portion 17, and part of the protruding surface 121, as shown in FIG. 2. The adhesive 19 is, for example, a thermosetting epoxy resin, and functions as a moisture-proof layer that prevents moisture from entering the liquid crystal layer 140 through the sealant 16.

[0015] Here, a liquid crystal device according to a comparative example will be described to explain the advantages of the liquid crystal device 10 according to the first embodiment. As shown in the cross-sectional view of Fig. 9 and the plan view of Fig. 10, the liquid crystal device according to the comparative example does not have the convex portion 17 of the embodiment.

[0016] 4 is a diagram showing the amount of variation in the cell gap in the first embodiment and the comparative example, along the direction opposite to the Y direction, from the edge B1 of the opposing substrate 15 to the edge B2 of the opposing substrate 15. Note that the solid line indicates the amount of variation in the cell gap in the first embodiment, and the dashed line indicates the amount of variation in the cell gap in the comparative example. The amount of variation in the cell gap is normalized with the maximum value in the comparative example being "1.0." The amount of variation in the cell gap indicates an increase from the state in which the substrates are bonded together at the design value with a positive value, and a decrease with a negative value.

[0017] In the comparative example, when the adhesive 19 applied to the side S hardens, the shrinkage that accompanies hardening causes the fluctuation amount at the end B1 to become negative, i.e., the cell gap at the end B1 narrows. In the comparative example, in the region A2 where the sealant 16 is provided, the cell gap is determined by the spacers contained in the sealant 16, so the fluctuation amount of the cell gap is almost zero. The narrowing of the cell gap in the region outside the sealant 16 in plan view causes the sealant 16 to act as a fulcrum, widening the cell gap in the display region A1. Therefore, in the comparative example, as shown by the dashed line, the cell gap in the display region A1 fluctuates, ultimately degrading the display quality.

[0018] A large number of liquid crystal devices 10 are produced on a wafer and then individually cut out by dicing. For this reason, a gap corresponding to region A3 is created between the sealing material 16 and the edge to provide a margin during dicing.

[0019] In contrast to the comparative example, in the first embodiment, the protrusions 17 provided on the outside of the sealing material 16 and having approximately the same height as the cell gap function as stoppers to suppress shrinkage due to hardening of the adhesive material 19. Therefore, even if shrinkage occurs due to hardening of the adhesive material 19, not only is the reduction in the cell gap outside the sealing material 16 suppressed, but the expansion of the cell gap in the display area A1 with the sealing material 16 as a fulcrum is suppressed to approximately 1 / 4. Therefore, according to the first embodiment, the intrusion of moisture into the liquid crystal layer 140 through the sealant 16 can be prevented, and fluctuations in the cell gap can be suppressed.

[0020] As can be seen from Figure 4, in the first embodiment and the comparative example, although to different degrees, the end B1 where the protruding surface 121 is located tends to have a larger variation in the cell gap than the end B2 where the element substrate 12 and the opposing substrate 15 are aligned. 2, at end B1, the adhesive 19 is applied to the side surface and protruding surface 121 of the opposing substrate 15, so the shrinkage stress caused by hardening acts more strongly on the opposing substrate 15 than on the element substrate 12. In contrast, at end B2, the adhesive 19 is applied to the side surface of the element substrate 12 and the side surface of the opposing substrate 15, so the shrinkage stress caused by hardening is distributed to the element substrate 12 and the opposing substrate 15. Therefore, the shrinkage stress of the cell gap acts more strongly on end B1 than on end B2, so it is thought that the amount of gap variation around the sealing material 16 as a fulcrum is larger near end B1. Therefore, a second embodiment that takes this into consideration will be described.

[0021] FIG. 5 is a cross-sectional view of a liquid crystal device 10 according to a second embodiment, taken along the Y direction, and FIG. 6 is a plan view of the liquid crystal device 10 according to the second embodiment. As described in the first embodiment, the cell gap reduction stress acts largely at the end B1 where the adhesive 19 is applied to the side surface and the protruding surface 121 of the counter substrate 15. For this reason, in the second embodiment, a protrusion 17 serving as a stopper to suppress shrinkage due to hardening of the adhesive 19 is provided only on the side S of the end B1. In detail, as shown in the cross-sectional view of FIG. 5 and the plan view of FIG. 6, the protrusion 17 is provided in a region outside the sealing material 16 in a plan view and along only the side S, while the adhesive 19 is applied to the side surfaces of three sides of the element substrate 12 and the counter substrate 15 and the side surface of the side S of the counter substrate 15, as in the embodiment.

[0022] According to the second embodiment, the area where the convex portion 17 is formed is reduced compared to the first embodiment, and moisture is prevented from entering the liquid crystal layer 140 via the sealing material 16, and fluctuations in the cell gap can be suppressed.

[0023] The above-described first and second embodiments (hereinafter referred to as "embodiments, etc.") can be applied and modified as follows.

[0024] FIG. 7 is a perspective view showing the configuration of a liquid crystal device 10 according to a modified example. As shown in this figure, in this modification, a dustproof glass 32 is attached to the Y-direction exit surface of the element substrate 12, and a dustproof glass 35 is attached to the Y-direction entrance surface of the counter substrate 15.

[0025] In a configuration in which the liquid crystal device 10 is applied to a light valve of a projection display device (described later), if dust or dirt adheres to the exit surface of the element substrate 12, the adhesion will be magnified and projected, resulting in a deterioration in display quality. To prevent this, a dust-proof glass 32 is attached to the exit surface of the element substrate 12. Similarly, if dust or dirt adheres to the entrance surface of the counter substrate 15, the adhesion will be magnified and projected, so a dust-proof glass 35 is attached to the entrance surface of the counter substrate 15 to prevent the adhesion of the adhesion. Note that the dust-proof glasses 32 and 35 are each made of a light-transmitting and insulating substrate such as glass, quartz, or sapphire.

[0026] According to this modification, even if dust or dirt adheres to the dustproof glass 32, 35, the adhesions are moved away from the focal point by the thickness of the glass, so that the adhesions are projected in an enlarged state while being blurred, thereby preventing a decrease in display quality.

[0027] In the embodiments, the liquid crystal device 10 has been described as a transmissive type, but it may also be configured as a reflective type by, for example, using a reflective metal film for the pixel electrode 120 or providing a reflective layer below the pixel electrode 120.

[0028] The element substrate 12 is an example of a "first substrate," the opposing substrate 15 is an example of a "second substrate," the adhesive 19 is an example of an "adhesive portion," and the FPC substrate 61 is an example of a "wiring substrate."

[0029] Next, a projection display device will be described as an example of an electronic device that uses the liquid crystal device 10 described in the embodiment.

[0030] 8 is a diagram showing the optical configuration of projection display device 200. As shown in the figure, projection display device 200 includes liquid crystal devices 10R, 10G, and 10B. A lamp unit 2102 consisting of a white light source such as a halogen lamp is provided inside projection display device 200. Light emitted from this lamp unit 2102 is separated into three primary colors, red (R), green (G), and blue (B), by three mirrors 2106 and two dichroic mirrors 2108 arranged inside. Of these, R light enters liquid crystal device 10R, G light enters liquid crystal device 10G, and B light enters liquid crystal device 10B.

[0031] The optical path of B is longer than that of the other colors red and green. Therefore, to prevent loss in the optical path, the B light is guided to the liquid crystal device 10B via a relay lens system 2121 consisting of an input lens 2122, a relay lens 2123, and an output lens 2124.

[0032] The liquid crystal device 10R is driven based on a data signal corresponding to R to generate an R transmission image. Similarly, the liquid crystal device 10G generates a G transmission image based on a data signal corresponding to G, and the liquid crystal device 10B generates a B transmission image based on a data signal corresponding to B.

[0033] The color transmission images generated by the liquid crystal devices 10R, 10G, and 10B are incident on the dichroic prism 2112 from three directions. The dichroic prism 2112 refracts the R and B light at 90 degrees, while the G light travels straight. Therefore, after the color images are combined, a color image is projected onto the screen Scr by the projection lens 2114.

[0034] In addition, electronic devices including the liquid crystal device 10 can be applied to not only the projection display device 200, but also head-mounted displays, electronic viewfinders in video cameras and interchangeable lens digital cameras, smart watches, and display units of wearable devices.

[0035] From the above-described exemplary embodiments, the following aspects can be understood, for example.

[0036] A liquid crystal device according to one aspect 1 comprises a first substrate having terminals electrically connected to a wiring substrate, a second substrate bonded to the first substrate via a sealing material, and a liquid crystal layer disposed between the first substrate and the second substrate, wherein the second substrate has a convex portion that protrudes toward the first substrate at least on the terminal-side edge of the first substrate, outside the sealing material in a planar view, and further has an adhesive portion that bonds the first substrate to the terminal-side side of the second substrate. According to the first aspect, the sealant prevents moisture from entering the liquid crystal layer, and also suppresses fluctuations in the gap between the first substrate and the second substrate, that is, the so-called cell gap.

[0037] In a liquid crystal device according to a second specific aspect of the first aspect, the convex portion is provided from the sealing material to an end of the second substrate in a plan view.

[0038] In a liquid crystal device according to a third specific aspect of the second aspect, the convex portions are provided along sides of the first substrate other than the side on the terminal side.

[0039] In a liquid crystal device according to a fourth specific aspect of the first aspect, the convex portions are made of SiO 2 .

[0040] In a liquid crystal device according to a fifth specific aspect of the first aspect, pixel electrodes are provided on the first substrate within the frame of the sealing material in a plan view, and a common electrode is provided on the second substrate.

[0041] An electronic device according to a sixth aspect includes the liquid crystal device according to any one of the first to fifth aspects. [Explanation of symbols]

[0042] 10...liquid crystal device, 12...element substrate, 15...opposing substrate, 16...sealing material, 17...protrusion, 19...adhesive, 120...pixel electrode, 140...liquid crystal layer, 150...common electrode, 61...FPC substrate, 200...projection display device.

Claims

1. a first substrate having terminals electrically connected to the wiring substrate; a second substrate bonded to the first substrate via a sealant; a liquid crystal layer disposed between the first substrate and the second substrate; the second substrate has a protrusion that protrudes toward at least the first substrate on an edge of the first substrate on the terminal side and outside the sealing material in a plan view; The first substrate and the second substrate further have an adhesive portion that adheres to the terminal side of the second substrate. Liquid crystal device.

2. The convex portion is From the sealing material to the edge of the second substrate in a plan view be established The liquid crystal device according to claim 1 .

3. The convex portion is The first substrate is provided along an edge other than the edge on the terminal side. The liquid crystal device according to claim 2 .

4. The convex portion is SiO ２ is The liquid crystal device according to claim 1 .

5. a pixel electrode is provided on the first substrate within a frame of the sealing material in a plan view; The second substrate is provided with a common electrode. The liquid crystal device according to claim 1 .

6. 6. An electronic device comprising the liquid crystal device according to claim 1.

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