JP2010181640A - Liquid crystal display panel and method for manufacturing liquid crystal display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display panel whose display unevenness is prevented and which has satisfactory viewing angle characteristics. <P>SOLUTION: In the liquid crystal display panel including a stuck substrate 12 having a pair of substrates and a liquid crystal layer, a microlens array 14 provided on the surface of the stuck substrate 12 and comprising a plurality of microlenses 14a each having a convex surface swelling on the side opposite to the stuck substrate 12, a supporting body 26 provided on the surface of the stuck substrate 12 so as to enclose the microlens array 14, a protective layer 35 disposed so as to come into contact with the end part of the supporting body 26 and respective vertex parts of the plurality of microlenses 14a, and an optical film 23 disposed on the side opposite to the microlens array 14 of the protective layer 35, difference between positions of the end part of the supporting body 26 and tip parts of the convex surfaces of the plurality of microlenses 14a is more than 0 μm and not more than 5 μm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal display panel, and more particularly to a liquid crystal display panel including a microlens array.

  In recent years, liquid crystal display devices have been widely used as display devices in monitors, projectors, portable information terminals, mobile phones, and the like. In general, a liquid crystal display device changes the transmittance (or reflectance) of each pixel by applying a display voltage corresponding to an image signal to each of the pixels regularly arranged in a matrix on the liquid crystal panel. Display.

  The liquid crystal display device includes a direct-view type liquid crystal display device that directly observes an image displayed on the liquid crystal display panel, and a projection type liquid crystal display that projects an image displayed on the display panel on a screen by a projection lens. There is a device (projector). The direct-view type liquid crystal display device includes a reflection type liquid crystal display device that displays light by reflecting light incident from the display surface side, and a transmission type that transmits light emitted from a light source such as a backlight and performs display. There are liquid crystal display devices and transflective (reflective-transmissive) liquid crystal display devices in which a reflective type and a transmissive type are combined.

  A typical transmissive or transflective liquid crystal display device includes a pair of polarizing elements (typically polarizing plates) arranged outside a TFT substrate and a counter substrate of a liquid crystal display panel. Display is performed by dimming the transmitted light of each pixel. In such a liquid crystal display device, since the transmitted light is shielded by the TFT, the gate bus line, the source bus line, and the light shielding layer (BM), the ratio of the effective pixel area to the entire display region, that is, the aperture ratio decreases. . Even if the pixel size is reduced, it is difficult to form TFTs, bus lines, etc. thin due to restrictions on electrical performance, manufacturing technology, etc., so the aperture ratio is significantly reduced in high-definition or small-sized liquid crystal display devices. Become.

  In order to improve the light utilization efficiency of the liquid crystal display device, a method of improving the effective aperture ratio of the liquid crystal display panel by providing a microlens for condensing light on each pixel in the liquid crystal display panel is disclosed in, for example, Patent Document 1. It is described in. In the liquid crystal display device of Patent Document 1, a convex microlens is provided on the backlight incident side of the TFT substrate.

  The microlens of Patent Document 1 irradiates a photocurable resin applied on a substrate from the CF substrate (color filter substrate) side through a pixel opening, and then performs a photolithography process such as development and heating. However, in the light irradiation process, so-called self-alignment exposure, in which exposure is performed by changing the incident angle of light transmitted through the pixel opening, is employed. According to this exposure method, since the microlens is formed in a self-aligned manner corresponding to each pixel (formation of the microlens by the self-alignment method), alignment of the mask for forming the microlens becomes unnecessary, and the pixel Positioning of the opening and the microlens array can be performed with extremely high accuracy.

  Other methods for forming microlenses are described in Patent Documents 2 to 5. The microlens of Patent Document 2 is formed by irradiating an ultraviolet curable resin filled in a depression of a substrate with ultraviolet rays from the backlight irradiation side (from the side opposite to the CF substrate) through a mask. Therefore, the method for forming the microlens is different from the method for forming the microlens in a self-aligned manner described in Patent Document 1. The microlenses of Patent Documents 3 and 4 are formed by irradiating a photocurable resin with light after transferring the shape of the microlens by pressing the photocurable resin with a stamper. Patent Document 5 describes the use of a microlens in which uniform convex portions and concave portions are alternately formed in order to improve the light utilization efficiency.

  The microlens arrays of Patent Documents 3 and 4 are formed by pressing a stamper onto an ultraviolet curable resin. However, in such a method using the stamping molding, it is difficult to align the stamper and the substrate. It is difficult to make the positions of the two coincide with each other as accurately as the method of Patent Document 1. Further, the ultraviolet curable resin after pressing the stamper may be stretched, which causes a problem that the positions of the microlens and the pixel are not matched.

JP 2005-196139 A JP-A-2005-208553 JP 2006-47708 A JP 2004-12941 A JP 2003-262706 A

  FIG. 7 is a cross-sectional view illustrating a transmissive liquid crystal display panel 100 including microlenses, and FIG. 8 illustrates a D-D ′ cross section of the liquid crystal display panel 100 in FIG. 7.

  As shown in FIGS. 7 and 8, the liquid crystal display panel 100 includes a bonded substrate 112 and a microlens that includes a plurality of microlenses 114a disposed on the lower surface (the surface on the backlight light incident side) of the bonded substrate 112. And an array 114. The bonded substrate 112 includes a TFT substrate 130, a CF substrate (color filter substrate) 132 which is a counter substrate, and a liquid crystal layer 134 sandwiched between the TFT substrate 130 and the CF substrate 132. The side surface of the liquid crystal layer 134 is covered with a sealing material 136 for enclosing the liquid crystal. Each microlens 114a is a lenticular lens extending along the pixel array direction.

  A support 126 is formed on the lower surface of the bonded substrate 112 so as to surround the microlens array 114. Below the microlens array 114, the apex of the microlens 114 a and the lower end of the support 126 are formed. A protective layer 135 is attached so as to be in contact with the surface. An optical film 123 is attached to the lower surface of the protective layer 135 via an adhesive layer 137, and the optical film 122 is attached to the upper surface of the CF substrate 132 via an adhesive layer 124. Each of the optical films 122 and 123 includes a polarizing plate. The optical films 122 and 123 may include optical elements such as a retardation plate and a light diffusion sheet.

  Since the protective layer 135 is supported by the apex portion of the microlens 114 a and the support body 126, the optical film 123 is stably held on the microlens array 114. However, in this case, since a closed internal space (gap) is formed between the microlens array 114 and the protective layer 135, water droplets adhere to the surface of the microlens 114a due to environmental changes such as temperature and atmospheric pressure. Or the peripheral member of the optical film 123 may be deformed due to the expansion and contraction of the air in the internal space.

  In order to solve this problem, it is conceivable to form a vent hole in a part of the support 126 that allows air to move between the internal space and the outside of the apparatus. However, simply providing a vent hole in the support body 126 would block the vent hole by the microlens adjacent to the support body 126, and thus could not connect the entire internal space to the external space.

  None of the above-mentioned Patent Documents 1 to 5 discuss the problem concerning the internal space and the vent hole, and means for solving this problem is not shown in these Patent Documents. Absent.

  In order to enable movement of air between the internal space and the external space, it is conceivable to form a gap between the periphery of the microlens array 114 and the support 126. A modification of the liquid crystal display panel 100 having such a configuration is shown in FIG. FIG. 9 shows a cross section of a modification corresponding to the E-E ′ cross section of the liquid crystal display panel 100 in FIG. 8.

  As shown in FIG. 9, in the liquid crystal display panel 100 ′ according to the modification, a gap 127 is provided between the periphery of the microlens array 114 and the support 126. Since the support 126 is provided with a vent hole (not shown), all the internal spaces (the gap 127 and the gap 128 above the microlens array 114) are connected to the external space through the vent holes. As a result, the above-described problem is solved in the liquid crystal display panel 100 '.

  However, when the inventor of the present application conducted an experiment, in such a liquid crystal display panel 100 ′, as shown in FIG. 9, peeling or adhesion between the microlens 114 a near the support 126 and the protective layer 135 was performed. It has been found that problems such as defects can occur. Further, even if the microlens 114a and the protective layer 135 are in contact with each other, there is a problem in that the contact area differs for each microlens 114a and the brightness and color tone vary.

  Furthermore, when the height of the microlens 14a is lower than the support to some extent, the protective layer 135 and the polarizing plate attached on the protective layer 135 may be peeled off, distorted, bent, etc. It has been found that it causes problems such as corner reduction. Furthermore, if the apex position of the microlens 114a differs by a certain degree along the ridge line direction of the lenticular lens, the width of the contact surface between the microlens 114a and the protective layer 135 is different, and a difference occurs in the optical path of transmitted light for each pixel. There was also a problem that the brightness and color tone varied.

  10A shows an optical path of transmitted light when the contact surface 150 between the microlens 114a and the protective layer 135 is wide, and FIG. 10B shows an optical path of transmitted light when the contact surface 150 is narrow. ing. As shown in FIGS. 10A and 10B, when the contact surface 150 between the microlens 114a and the protective layer 135 is wide, light traveling straight through the contact surface 150 increases, so that the contact surface is narrow compared to the case where the contact surface is narrow. As a result, the front brightness increases and the amount of diffused light decreases accordingly. Therefore, if the contact area between the microlens 114a and the protective layer 135 is different, the viewing angle characteristics differ depending on the pixel, and problems such as display unevenness occur.

  11A and 11B show three micro lenses 114a viewed from the vertical direction of the substrate surface, and FIG. 11A shows a change in the contact surface 150 along the ridge line direction of the lenticular lens. FIG. 11B shows a case where the contact surface 150 does not change. Reference numerals 90a, 90b, and 90c in FIG. 11A represent pixels for displaying red, green, and blue, respectively (referred to as red pixels, green pixels, and blue pixels, respectively). These three pixels 90a, 90b, and 90c constitute one display unit 90. A plurality of display units 90 are arranged in a matrix along the direction in which the microlenses 114a extend and the direction perpendicular thereto.

  As shown in FIG. 11A, when the width of the contact surface 150 changes along the extending direction of the micro lens 114a, the light is transmitted between the red pixel 90a, the green pixel 90b, and the blue pixel 90c, or between display units. The optical path of light is different, causing problems such as display unevenness. Therefore, in the liquid crystal display panel, as shown in FIG. 11B, the width of the contact surface 150 is preferably more uniform along the extending direction of the microlenses 114a.

  Conventionally, with respect to the liquid crystal display panel 100 having the above-described configuration, there has not been studied a problem of how a high-quality display can be obtained by using a contact form between the microlens 114a and the protective layer 135. The structural requirements around the microlens 114a for obtaining a good contact form between the two have not been studied.

  The present invention has been made in view of the above-described problems, and the object thereof is a liquid crystal display panel with a microlens with high display quality in which occurrence of display unevenness or light leakage is suppressed, or an excellent viewing angle characteristic. The object is to provide a liquid crystal display panel.

  A liquid crystal display panel according to the present invention is provided on a surface of a bonded substrate having a pair of substrates, a liquid crystal layer disposed between the pair of substrates, and each of the bonded substrates, Is a microlens array composed of a plurality of microlenses having convex surfaces bulging on the opposite side, a support provided on the surface of the bonded substrate so as to surround the microlens array, and the microlens array A protective layer disposed on the opposite side of the bonded substrate so as to be in contact with an end portion of the support and each apex portion of the plurality of microlenses, and the microlens array of the protective layer is opposite to the microlens array An optical film disposed on the side, and the end of the support and the tips of the convex surfaces of the plurality of microlenses in the surface vertical direction of the bonded substrate The difference between the positions of the parts is a large 5μm or less than 0 .mu.m.

  In one embodiment, the plurality of microlenses are made of a photocurable resin cured by irradiating light through the openings of the plurality of pixels.

  In one embodiment, an air gap exists between an end of the microlens array and the support.

  In one embodiment, the width of the gap between the end of the microlens array and the support is 50 μm or more and 250 μm or less.

  In one embodiment, a gap or a slit that connects an internal space surrounded by the support and an external space is formed in the support.

  An embodiment includes a transparent layer having a substantially uniform thickness, which is formed between the microlens array and the surface of the bonded substrate.

  In one embodiment, each of the plurality of microlenses is a lenticular lens extending along an arrangement direction of pixels, and a difference between a position closest to the optical film and a position farthest from the optical film at a tip portion of the lenticular lens is 2 μm. It is as follows.

  A method of manufacturing a liquid crystal display panel according to the present invention includes a pair of substrates, a liquid crystal layer disposed between the pair of substrates, a bonding substrate having a plurality of pixels, and a surface provided on the surface of the bonding substrate. A microlens array composed of a plurality of microlenses each having a convex surface that swells on the opposite side of the bonded substrate, and provided on the surface of the bonded substrate so as to surround the microlens array. A liquid crystal display panel comprising: a support; and a step of disposing a photocurable resin on the surface of the bonded substrate; and irradiating light through each opening of the plurality of pixels. Curing the photo-curable resin to form the microlens array, and forming the support on the surface of the bonded substrate. Forming a protective layer on the side of the microlens array opposite to the bonded substrate so as to be in contact with the end of the support and each apex of the plurality of microlenses; Disposing an optical film on the side opposite to the microlens array, and in the surface vertical direction of the bonded substrate, the end of the support and the tip of the convex surface of the plurality of microlenses The support and the microlens array are formed so that the difference in position between the support and the microlens array is greater than 0 μm and less than or equal to 5 μm.

  In one embodiment, a gap is formed between an end of the microlens array and the support.

  An embodiment includes a step of forming a gap or a slit in the support that connects an internal space surrounded by the support and an external space.

  In one embodiment, the gap has a width of 50 μm or more and 250 μm or less.

  An embodiment includes the step of curing the photocurable resin to form a transparent layer having a substantially uniform thickness between the microlens array and the surface of the bonded substrate.

  In one embodiment, each of the plurality of microlenses is a lenticular lens extending along an arrangement direction of pixels, and a difference between a position closest to the optical film and a position farthest from the optical film at a tip portion of the lenticular lens is 2 μm. The plurality of microlenses are formed as follows.

  According to the present invention, it is possible to obtain a liquid crystal display panel with high display quality or improved viewing angle characteristics in which light leakage (light leakage) and display unevenness are reduced.

It is sectional drawing which showed typically the structure of the liquid crystal display panel 10 by embodiment of this invention. FIG. 2 is a diagram showing a cross section taken along line A-A ′ in FIG. 1 of the liquid crystal display panel 10. FIG. 3 is a diagram showing a B-B ′ cross section in FIG. 2 of the liquid crystal display panel 10. (A) is the perspective view showing the shape of the micro lens 14a of the liquid crystal display panel 10, (b) is the figure showing the shape of the micro lens 14a in CC 'cross section of FIG.2 and FIG.4 (a). It is. (A) represents the relationship between the height of the microlens 14a and the quality of the liquid crystal display panel 10, and (b) represents the relationship between the variation in the vertex position of the microlens 14a and the quality of the liquid crystal display panel 10. . (A)-(d) is a figure showing the manufacturing method of the liquid crystal display panel 10. FIG. It is sectional drawing which represented typically the structure of the liquid crystal display panel 100 provided with the micro lens. FIG. 2 is a diagram illustrating a configuration in a DD ′ section of a liquid crystal display panel 100. FIG. 9 is a diagram illustrating a configuration corresponding to a cross section taken along line EE ′ of FIG. 8 of a liquid crystal display panel 100 ′ that is a modification of the liquid crystal display panel 100. (A) And (b) is the figure showing the relationship between the contact surface of the micro lens 114a and the protective layer 135, and transmitted light. (A) And (b) is a figure showing the contact surface of the micro lens 114a and the protective layer 135. FIG.

  Hereinafter, a liquid crystal display panel 10 according to an embodiment of the present invention will be described with reference to the drawings. However, the scope of the present invention is not limited to the following embodiments.

  FIG. 1 is a cross-sectional view schematically showing the configuration of the liquid crystal display panel 10, and FIG. 2 is a view showing the A-A ′ cross section in FIG. 1 of the liquid crystal display panel 10.

  As shown in FIGS. 1 and 2, the liquid crystal display panel 10 includes a bonded substrate 12, and a resin layer 16 disposed on the surface of the bonded substrate 12 on the backlight light incident side (lower side in FIG. 1). The optical film 22 provided on the observer side of the bonded substrate 12 (upper side in FIG. 1), and the protective layer 35 and the optical film 23 provided on the backlight incident side of the resin layer 16 are provided.

  The resin layer 16 includes a plurality of microlenses 14a (microlens array 14) and a flat layer (transparent layer) 15 described later with reference to FIG. The plurality of microlenses 14a are semi-cylindrical lenticular lenses each convex in the backlight light incident side direction, and are arranged so as to correspond to one row of pixels arranged in a matrix.

  The bonded substrate 12 includes a TFT substrate 30 including pixel electrodes and switching elements formed for each pixel, a CF substrate 32 as a counter substrate, and a liquid crystal layer 34 disposed between the TFT substrate 30 and the CF substrate 32. Prepare. The liquid crystal layer 34 is sealed by a sealing material 36 provided on the display outer peripheral portion between the TFT substrate 30 and the CF substrate 32.

  The optical film 22 and the optical film 23 are bonded to the bonded substrate 12 and the protective layer 35 via an adhesive layer (not shown), respectively. Each of the optical film 22 and the optical film 23 includes a polarizing plate. The optical film 22 and the optical film 23 may include optical elements such as a viewing angle compensation plate and a retardation plate.

  The microlens array 14 and the flat layer 15 of the resin layer 16 are made of UV light from a CF substrate 32 side by using a dry film made of UV curable resin (ultraviolet curable resin) attached to the backlight incident side of the TFT substrate 30. It is obtained by curing by irradiating (ultraviolet rays). At this time, in order to realize the semi-cylindrical lens shape of each microlens 14a, UV light is irradiated through the respective openings of the plurality of pixels, and the incident angle of the UV light to the liquid crystal display panel is stepped. For example, a self-alignment method such as that described in Patent Document 1 is used. The resin layer 16 is made of an acrylic UV curable resin having a high visible light transmittance, but may be formed of an epoxy UV curable resin or another type of photocurable resin.

  A columnar support 26 is formed on the surface of the bonded substrate 12 so as to surround the microlens array 14. The support 26 is obtained, for example, by attaching a dry film made of a UV curable resin to the TFT light incident side of the TFT substrate 30 and irradiating the dry film with UV light through a photomask. As shown in FIG. 2, vent holes (gap or slit) 26 a and 26 b are formed in the portion of the support 26 corresponding to the corners of the bonded substrate 12. The vent holes 26 a and 26 b connect the internal space surrounded by the support 26 and the external space of the liquid crystal display panel 10, and the resin layer 16 is provided between the support 26 and the end of the microlens array 14. A void 27 that does not exist is formed.

  In FIG. 2, one form of the air holes is shown by the air holes 26 a and 26 b, but the number and positions of the air holes are not limited to this form. The air holes may be formed at other corners or may be formed at portions other than the corners. Further, a larger number of ventilation holes may be formed. The shape of the vent is not limited to a linearly extending shape, and may be formed in other shapes such as a curved shape or a bent shape in the middle.

  The protective layer 35 is formed of an acrylic UV curable resin having a high visible light transmittance, like the microlens array 14, but an epoxy UV curable resin or the like is also applied to the protective layer 35. It is also possible. The protective layer 35 is preferably formed of the same material as the microlens 14a or a material having substantially the same refractive index as the material constituting the microlens 14a, but may be formed of different materials. The support 26 is also preferably formed of the same material as that of the microlenses 14a, but may be formed of a different material.

  FIG. 3 shows the microlens array 14, the flat layer 15, the support 26, and the protective layer 35 in the B-B ′ cross section of FIG. 2.

  As shown in FIG. 3, the flat layer 15 has a substantially uniform thickness a over the entire bottom of the microlens array 14. In other words, the thickness a of the flat layer 15 can also be referred to as a distance between the end of the microlens 14 a on the surface of the flat layer 15 and the surface of the bonded substrate 12. The thickness a of the flat layer 15 is about 10 μm in this embodiment.

  The thickness of the microlens array 14, that is, the thickness b of the apex portion having the largest thickness in the microlens 14a is about 18 μm in this embodiment. Therefore, the total thickness of the microlens 14a and the flat layer 15 at the apex portion of the microlens 14a is about 28 μm. The thickness of the support 26, that is, the distance between the end of the support 26 on the protective layer 35 side and the surface of the bonded substrate 12 is about 30.5 μm. Therefore, the difference between the thickness of the support and the thickness of the resin layer at the apex portion of the microlens 14a, that is, the end of the support 26 and the tip of the convex surface of the microlens 14a in the surface vertical direction of the bonded substrate 12. The difference d in the position is about 2.5 μm. The position difference d is preferably greater than 0 μm and not greater than 5 μm.

  The thickness a of the flat layer 15 is preferably 2.0 μm or more, and it has been confirmed by experiments that this prevents the microlens from being peeled off and poor adhesion to the substrate. In order to reliably prevent peeling and poor adhesion with high accuracy, the thickness a of the flat layer 15 is preferably 3.0 μm or more. Moreover, since it is not preferable to form the resin layer 16 unnecessarily thick from the viewpoint of optical characteristics and manufacturing cost, the thickness a of the flat layer 15 is preferably 20.0 μm or less.

  In the case where the microlens array 14 is manufactured by the method of Patent Document 1, a plurality of microlenses having a convex shape on the backlight light incident side can be obtained by reducing the amount of exposure to the portion corresponding to the end of each microlens 14a. 14a is formed. At this time, the amount of exposure is very small near the end of each microlens 14a (the boundary between adjacent microlenses 14a), and in some cases it becomes zero, so the resin thickness is extremely thin or the resin layer is missing. There is a possibility that a part or a part where the resin layer is not formed may be generated.

  Further, according to the method of Patent Document 2, it is formed by irradiating light from the backlight light incident side through a mask. This mask is formed only on a portion corresponding to the central portion of each microlens 14a. A transmission part is formed. Accordingly, also here, the exposure amount is very small near the end of each microlens 14a or, in some cases, zero, so that there are portions where the resin thickness is extremely thin, lacked, or where the resin layer is not formed. .

  Cracks are likely to occur in the extremely thin part formed by the above-described method. In the development stage or the subsequent manufacturing process, the cracks, the part lacking the resin layer, or the part where the resin layer was not formed As a starting point, it has been found that the microlens 14a itself is cracked, and that a poor adhesion such as peeling occurs between the microlens 14a and the bonded substrate 12. Such cracks and poor adhesion cause display unevenness and luminance reduction in the liquid crystal display device.

  Further, as shown in FIG. 2, the support body 26 of the present embodiment is formed with vent holes 26 a and 26 b that connect the internal space and the external space, and the support body 26 and the end of the microlens array 14. There is a gap 27 between them. The width c of the gap 27, that is, the distance c between the support 26 and the end of the microlens array 14 shown in FIG. 3 is about 75 μm in this embodiment.

  The air smoothly moves between the internal space (in this embodiment, the air gap 27 and the air gap 28 between the microlens array 14 and the protective layer 35) and the external space without blocking the air holes 26a and 26b. For this purpose, the width d of the gap 27 is preferably 50 μm or more. In order not to unnecessarily enlarge the liquid crystal display panel, the width d of the gap 27 is preferably 250 μm or less. The distance between the support 26 and the end of the microlens array 14 is larger than the width d, and this distance may be 50 μm or more and 250 μm or less from the viewpoint of ease of air movement and the size of the liquid crystal display panel. preferable.

  By adopting such a configuration, generation of bubbles in the internal space and deformation of the peripheral members of the microlens are prevented, and a highly reliable liquid crystal display panel with excellent brightness and contrast can be provided.

  4A is a perspective view showing the shape of the microlens 14a, and FIG. 4B shows the shape of the microlens 14a in the CC ′ section of FIGS. 2 and 4A. . The microlens 14a is a lenticular lens that extends along one arrangement direction of pixels arranged in a matrix. As shown in FIGS. 3 and 4A, each microlens 14a has a curved surface (convex surface) 14b bulging in a convex shape. Let the apex (tip part) of the curved surface 14b be 14c. FIG. 4B shows a cross-sectional shape of the micro lens 14a at the position of the vertex 14c along the extending direction of the lenticular lens.

  When the position of the vertex 14c is viewed along the extending direction of the lenticular lens, the position of the vertex 14c (or the thickness of the microlens 14a at the position of the vertex 14c) changes as shown in FIG. 4B. (In FIG. 4B, the change is extremely expressed). Let e be the maximum value of the position of the apex 14c in one microlens 14a, that is, the difference between the position closest to the optical film and the position farthest from the optical film. In the present embodiment, the microlens 14a is formed so that the difference e is 2.0 μm or less. According to the measurement, the difference e in the present embodiment was 0.6 μm.

  5A shows the relationship between the distance d shown in FIG. 3 and the quality of the liquid crystal display panel 10, and FIG. 5B shows the difference e shown in FIG. 4B and the liquid crystal display panel. The relationship with 10 quality is expressed. In FIG. 5A, “o” indicates that the degree of light leakage (light leakage caused by distortion or deflection of the polarizing plate) generated in the liquid crystal display panel 10 and peeling of the protective layer 35 are within an allowable range. The fact that these values exceed the allowable range is indicated by “x”. In FIG. 5B, “○” indicates that the adhesion between the microlens 14a and the protective layer 35 and the occurrence of color change (color unevenness or display unevenness) in the display are within an allowable range. Exceeding the allowable range is indicated by “x”.

  When liquid crystal display panels 10 having different distances d were experimentally manufactured and their quality was confirmed, as shown in FIG. 5A, the light d (light leakage) and the protective layer 35 were peeled off when the distance d was 5 μm or less. It was found that it was within the allowable range. However, when the distance d is 0 (zero), the contact surface between the microlens 14a and the protective layer 35 becomes too large. Therefore, the distance d is preferably larger than 0 μm and not larger than 5 μm. Further, when the quality was confirmed by experimentally manufacturing the liquid crystal display panel 10 having a different difference e, as shown in FIG. 5 (b), the adhesion force and the color change are allowed when the difference e is 2 μm or less. It was found to be within the range.

  By setting the distance d and the difference e within these ranges, it is preferable that the microlens 14a, the protective layer 35, and the contact surface 150 are desirable as shown in FIGS. 10 (b) and 11 (b). it can. Therefore, display unevenness and light leakage of the liquid crystal display panel 10 can be suppressed, and viewing angle characteristics can be improved.

  Next, the manufacturing method of the liquid crystal display panel 10 is demonstrated using FIG.

  6A to 6D are cross-sectional views schematically showing a method for manufacturing the liquid crystal display panel 10.

  First, a bonded substrate 12 including a TFT substrate 30 on which a switching element is formed for each pixel and a CF substrate 32 as a counter substrate is prepared, and a backlight light incident side (the lower side of the drawing) of the bonded substrate 12 is prepared. A dry film 39 having a thickness of, for example, 30 μm is pasted on the surface. Thereafter, as shown in FIG. 6A, UV light is irradiated from the CF substrate 32 side through the pixel opening to form the microlens array 14. Specifically, when irradiating UV light, the alignment substrate 12 or a UV light source (not shown) is moved to perform self-alignment exposure that changes the relative position of the UV light with respect to the pixel opening, and each pixel is subjected to self-alignment exposure. The aligned microlens 14a is formed.

In self-alignment exposure, UV light is scanned in the direction in which the semi-cylindrical microlens 14a extends and in the direction perpendicular thereto. At this time, in the vicinity of the top of the lens, the light amount is irradiated with ^{50mJ / cm 2 (10mW / cm} 2 × 5 seconds) approximately UV light, at the end of the microlens 14a, the light quantity is 46mJ / cm ² (10mW / cm Illuminate with a light intensity of about ² x 4.6 seconds. By such exposure, the flat layer 15 shown in FIG. 3 is formed to a height of about 10 μm, and the thickness of the apex portion of the microlens 14 a is about 18 μm. The incident angle of the UV light may be either continuously changing or changing stepwise. At this time, the microlens 14a is shaped so that the difference e shown in FIG. 4B is 2 μm or less.

Next, as shown in FIG. 6B, the support 26 is formed by irradiating UV light from the backlight irradiation side through a photomask 40 having a transmission part corresponding to the support 26. When forming the support, in order to reduce the difference d between the vicinity of the top of the lens and the position of the support 26 as much as possible, UV light of about 50 mJ / cm ² (10 mW / cm ² × 5 seconds) equivalent to the vicinity of the top of the lens. Irradiate. Thereby, the position difference d can be formed to be larger than 0 μm and not larger than 5 μm.

  At this time, the support 26 is formed so that the outer periphery and the inner periphery are substantially rectangular when viewed perpendicularly to the substrate surface, and between the inner surface and the microlens array 14, FIG. 2 and FIG. 3 is formed. Further, as shown in FIG. 2, vent holes 26 a and 26 b for connecting the internal space and the external space are formed at the corners of the support body 26. However, the outer ends of the vent holes 26a and 26b are covered with UV resin at this point, and the vent holes 26a and 26b are opened to the external space by cutting the UV resin portion in a later cutting step. Is done.

  Thereafter, the uncured dry film 39 is removed by development processing. Thereby, the resin layer 16 having the microlens 14a and the flat layer 15 and the support body 26 are left. Thereafter, the dry film 39 is heated to further advance the curing of the resin layer 16 and the support 26. Here, the support 26 is formed such that the difference d between the apex portion of the microlens 14 a and the end of the support 26 is greater than 0 μm and less than or equal to 5 μm.

  Next, as shown in FIG. 6C, a dry film 41 made of the same material as the dry film 39 is pasted so as to be in contact with the apex of each microlens 14 a and the support 26. Thereafter, the dry film 41 is cured by irradiating UV light through the photomask 42 to form the protective layer 35. Here, the protective layer 35 is fixed to the apex of the micro lens 14 a and the lower end portion of the support portion 26. Accordingly, the protective layer 35 and the optical film 23 to be pasted on the protective layer 35 later can be arranged flat without distortion.

  Thereafter, development processing is performed to remove the uncured dry film 41, and further heating is performed to further cure the protective layer 35. Thereafter, the resin layer at the outer end portions of the vent holes 26a and 26b of the support 26 is cut away to open the vent holes 26a and 26b to the external space.

  Next, as shown in FIG. 6D, the optical film 23 is attached to the protective layer 35 via an adhesive layer. Further, the optical film 22 is attached to the CF substrate 32 via an adhesive layer, and the liquid crystal display panel 10 is completed.

  In this embodiment, the microlens array 14 and the protective layer 35 are formed on one liquid crystal display panel, and the optical film 23 is attached. However, the present invention is not limited to this, and a large substrate including a plurality of liquid crystal display cells. A plurality of liquid crystal display panels may be manufactured at the same time by forming the microlens array 14 and the protective layer 35 thereon and dividing the liquid crystal display panel. Furthermore, it is also possible to attach a large format optical film on a large substrate on which the microlens array 14 and the protective layer 35 are formed, and then to cut and peel the optical film and to divide the substrate.

  ADVANTAGE OF THE INVENTION According to this invention, the display quality of the liquid crystal display panel and liquid crystal display device which have a microlens can be improved.

10, 100 Liquid crystal display panel 12, 112 Bonded substrate 14, 114 Micro lens array 14a, 114a Micro lens 15 Flat layer 16 Resin layer 22, 23, 122, 123 Optical film 26, 126 Support 26a, 26b Vent 27, 28, 127, 128 Air gap 30, 130 TFT substrate 32, 132 CF substrate 34, 134 Liquid crystal layer 35, 135 Protective layer 36, 136 Sealing material 124, 137 Adhesive layer

Claims (13)

A bonded substrate having a pair of substrates and a liquid crystal layer disposed between the pair of substrates;
A microlens array comprising a plurality of microlenses provided on the surface of the bonded substrate, each having a convex surface that swells on the opposite side of the bonded substrate;
A support provided on the surface of the bonded substrate so as to surround the microlens array;
A protective layer disposed on the opposite side of the bonded substrate of the microlens array so as to be in contact with an end of the support and each vertex of the plurality of microlenses;
An optical film disposed on the side of the protective layer opposite to the microlens array,
The liquid crystal display panel, wherein a difference in position between the end portion of the support and the tip end portions of the convex surfaces of the plurality of microlenses in the surface vertical direction of the bonded substrate is greater than 0 μm and not more than 5 μm.   The liquid crystal display panel according to claim 1, wherein the plurality of microlenses are made of a photocurable resin cured by irradiating light through the openings of the plurality of pixels.   The liquid crystal display panel according to claim 1, wherein a gap exists between an end of the microlens array and the support.   The liquid crystal display panel according to claim 3, wherein a width of the gap between an end portion of the microlens array and the support is 50 μm or more and 250 μm or less.   5. The liquid crystal display panel according to claim 1, wherein a gap or a slit that connects an internal space surrounded by the support and an external space is formed in the support.   The liquid crystal display panel according to claim 1, further comprising a transparent layer formed between the microlens array and the surface of the bonded substrate and having a substantially uniform thickness. Each of the plurality of microlenses is a lenticular lens extending along a pixel arrangement direction,
The liquid crystal display panel according to claim 1, wherein a difference between a position closest to the optical film and a position farthest from the tip of the lenticular lens is 2 μm or less. A bonded substrate having a plurality of pixels, the substrate including a pair of substrates and a liquid crystal layer disposed between the pair of substrates;
A microlens array comprising a plurality of microlenses provided on the surface of the bonded substrate, each having a convex surface that swells on the opposite side of the bonded substrate;
A support provided on the surface of the bonded substrate so as to surround the microlens array, and a method for manufacturing a liquid crystal display panel,
Disposing a photocurable resin on the surface of the bonded substrate;
Curing the photocurable resin by irradiating light through each of the plurality of pixels to form the microlens array; and
Forming the support on the surface of the bonded substrate, and
Forming a protective layer on the side of the microlens array opposite to the bonded substrate so as to be in contact with an end of the support and each apex of the plurality of microlenses;
Placing an optical film on the opposite side of the protective layer from the microlens array,
The support so that a difference in position between the end of the support and the tips of the convex surfaces of the plurality of microlenses in the surface vertical direction of the bonded substrate is greater than 0 μm and less than or equal to 5 μm. And the manufacturing method of the liquid crystal display panel in which the said micro lens array is formed.   The manufacturing method according to claim 8, wherein a gap is formed between an end of the microlens array and the support.   The manufacturing method of Claim 8 or 9 including the step of forming the clearance gap or slit which connects the internal space and external space which were enclosed with the said support body in the said support body.   The manufacturing method of Claim 9 whose width | variety of the said space | gap is 50 micrometers or more and 250 micrometers or less.   12. The method according to claim 8, further comprising: curing the photocurable resin to form a transparent layer having a substantially uniform thickness between the microlens array and the surface of the bonded substrate. The manufacturing method as described in. Each of the plurality of microlenses is a lenticular lens extending along a pixel arrangement direction,
The plurality of microlenses are formed so that a difference between a position closest to the optical film and a position farthest from the optical film at a tip portion of the lenticular lens is 2 μm or less. Production method.

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