JP2015216034A - Manufacturing method for image display device, and image display device - Google Patents

Abstract

An object of the present invention is to provide a thin image display device capable of improving extraction efficiency of light emitted from pixels. Kind Code: A1 A method for manufacturing an image display device in which an optical element is provided so as to overlap a pixel portion provided with a plurality of pixels, wherein a resin is applied to the surface of a support substrate provided with a mold structure serving as a prototype of the optical element. A material is applied to bury the mold structure, and a first substrate having a substantially flat upper surface is formed. Provided is a method for manufacturing an image display device in which the first substrate is separated from the supporting substrate by laminating the first substrate so as to overlap with the region provided between the substrates and provided with the mold structure. [Selection drawing] Fig. 2

Description

  The present invention relates to a method for manufacturing an image display device in which pixels are configured by light emitting elements such as organic electroluminescence elements, and an image display device.

  An image display device in which an organic electroluminescence (hereinafter also referred to as “organic EL”) element is provided in each pixel displays an image by dynamically controlling light emission of the organic EL element by a transistor provided in each pixel. ing. Since the organic EL element deteriorates due to the influence of moisture or the like, the pixel portion in which the pixels are arranged is provided with a sealing structure to prevent moisture from entering. Various types of sealing structures have been studied. For example, one substrate on which a pixel portion is formed by a transistor or an organic EL element and the other substrate facing each other are overlapped, and the pixel portion is formed on both substrates. A structure is known that is sandwiched between and sealed.

  An image display device provided with an organic EL element in a pixel is called a bottom emission type in which light emission of the pixel is emitted to the substrate side where the transistor is formed, and a top emission type in which light emission is emitted to the substrate side to be sealed. It is distinguished. In any case, it is necessary that the substrate on the light emission side has translucency.

  In such an image display device, light emission of the organic EL element in each pixel is emitted through the substrate from the inside of the sealing body. Since light emitted from the organic EL element is emitted in all directions, light from the pixels is incident on the substrate at various angles. At this time, even if the sealing substrate is a light-transmitting substrate, the refractive index is usually larger than the refractive index of air (n = 1) (for example, the refractive index of glass is about 1. 5), the light incident at an angle greater than the critical angle with respect to the interface between the translucent substrate and air is totally reflected and cannot be extracted outside as an effective emitted light component.

  It is said that the light extraction efficiency of the light emitted from the organic EL element is about 20% to 30%, and improving the light extraction efficiency is a low power consumption in an image display device using the organic EL element. This is an extremely important issue from the viewpoint of computerization.

  Therefore, an image display apparatus is known in which an optical element such as a microlens is further added to a substrate on which light is emitted from a pixel in order to increase the light extraction efficiency. For example, an image display device is disclosed in which an optical sheet having a microlens array formed on the outside of a substrate is attached with an adhesive (see Patent Document 1). Also disclosed is an image display device in which a conversion layer that changes an optical path of light emitted from a pixel is further provided on a thin substrate after removing a temporary substrate serving as a support substrate that holds the thin substrate in the manufacturing process (patent) Reference 2).

JP 2004-241130 A JP 2004-207078 A

  However, as described in Patent Document 1, in the method of attaching an optical film having a microlens array formed on the surface of a transparent substrate with an adhesive, only the amount of the optical film and the adhesive added externally The thickness of the image display device increases. Further, as described in Patent Document 2, in the method of forming a conversion layer that changes the optical path of output light on a thin substrate after removing the temporary substrate, the number of manufacturing processes increases, resulting in a decrease in throughput and yield. It is a problem that a decrease in cost and an increase in cost occur.

  Accordingly, an object of the present invention is to provide an image display device that can improve the extraction efficiency of light emitted from a pixel while being thin. Another object of the present invention is to provide an image display device capable of improving the light extraction efficiency by a rational manufacturing process.

  According to one embodiment of the present invention, there is provided a method for manufacturing an image display device in which an optical element is provided on a pixel portion provided with a plurality of pixels, and a mold structure that is a prototype of the optical element is provided. A resin material is applied to the surface of the support substrate to embed the mold structure, and a first substrate having a substantially flat upper surface is formed. The first substrate provided on the support substrate is opposed to the second substrate, and the pixel portion is Provided is a method for manufacturing an image display device, which is disposed between a first substrate and a second substrate and is bonded so as to overlap an area where a mold structure is provided, and the first substrate is released from a support substrate.

  A light shielding layer and / or a color filter layer may be formed on the first substrate in accordance with the arrangement of a plurality of pixels. While forming a mold structure on one surface of the support substrate, an alignment mark for forming the light shielding layer and / or the color filter layer may be formed.

  The support substrate after releasing the first substrate may be reused in the manufacturing process of the image display device according to the embodiment of the present invention.

  The mold structure provided on the surface of the support substrate may be a regular concave structure or a convex structure. The mold structure provided on the surface of the support substrate may have a prototype of any one of a microlens array, a lenticular lens, and a moth-eye structure.

  You may make it form an organic electroluminescent element in a pixel part.

  According to an embodiment of the present invention, a pixel array in which a plurality of pixels are arranged is disposed between a pair of substrates, and the substrate side on which output light from the pixel array is emitted among the pair of substrates, There is provided an image display device in which optical elements having a non-planar surface structure are integrally formed.

  The surface structure of the optical element may be a regular concave structure or a convex structure. The optical element may be any one of a microlens array, a lenticular lens, and an element having a moth-eye structure.

  An organic electroluminescence element may be provided in each of the plurality of pixels.

The structure of the image display apparatus which concerns on one Embodiment of this invention is shown, (A) is a top view, (B) is sectional drawing. It is sectional drawing which shows the structure of the pixel part of the image display apparatus which concerns on one Embodiment of this invention. It is a flowchart explaining the manufacturing process of the image display apparatus which concerns on one Embodiment of this invention. It is sectional drawing explaining the manufacturing process of the image display apparatus which concerns on one Embodiment of this invention. It is sectional drawing explaining the manufacturing process of the image display apparatus which concerns on one Embodiment of this invention. It is sectional drawing explaining the manufacturing process of the image display apparatus which concerns on one Embodiment of this invention. The manufacturing process of the image display apparatus which concerns on one Embodiment of this invention is shown, and an example of a support substrate is shown, (A) is a top view, (B) is sectional drawing. It is sectional drawing explaining the manufacturing process of the image display apparatus which concerns on one Embodiment of this invention. It is sectional drawing explaining the manufacturing process of the image display apparatus which concerns on one Embodiment of this invention. It is sectional drawing explaining the manufacturing process of the image display apparatus which concerns on one Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. However, the present invention can be implemented in many different modes and should not be construed as being limited to the description of the embodiments exemplified below. In addition, the drawings may be schematically represented with respect to the width, thickness, shape, and the like of each part in comparison with actual aspects for the sake of clarity of explanation, but are merely examples, and the interpretation of the present invention is not limited. It is not limited. In addition, in the present specification and each drawing, elements similar to those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description may be omitted as appropriate.

  In this specification, when a member or region is “on (or below)” another member or region, this is directly above (or directly below) the other member or region unless otherwise specified. ) As well as the case above (or below) other members or regions, i.e., another component is included above (or below) other members or regions. Including cases.

[First Embodiment]
<Configuration of image display device>
1A and 1B show a configuration of an image display device according to an embodiment of the present invention. FIG. 1A is a plan view of the image display device 100, and FIG. 1B shows a cross-sectional structure corresponding to the line AB in the drawing.

  The image display apparatus 100 includes a pixel unit 106 in which a plurality of pixels are two-dimensionally arranged. The pixel portion 106 is provided on the second substrate 104. The second substrate 104 may be provided with a scanning line driver circuit 110, a video signal line driver circuit 112, an input terminal portion 114, and the like. The first substrate 102 faces the second substrate 104 and is provided so as to seal the pixel portion 106.

  The first substrate 102 and the second substrate 104 are fixed by a sealing material 116. The first substrate 102 and the second substrate 104 are fixed with a gap of several micrometers to several tens of micrometers, and a filler 118 is provided in the gap. A resin material is preferably used as the filler 118. The structure in which the pixel portion 106 is sandwiched between the first substrate 102 and the second substrate 104 and the filler 118 is sealed is also called solid sealing.

  Each pixel in the pixel portion 106 is provided with a light emitting element. As the light emitting element, for example, an organic EL element in which an organic EL material is used for the light emitting layer is applied. The light emission of each pixel in the pixel unit 106 is individually controlled by a pixel circuit. A signal for controlling light emission of each pixel is supplied from the scanning line driving circuit 110 and the video signal line driving circuit 112.

  The image display device 100 shown in FIG. 1 has a top emission type structure in which light emission from the pixel portion 106 is emitted to the first substrate 102 side.

  In FIG. 1, an optical element 108 is provided on the first substrate 102 so as to overlap with the pixel portion 106. The optical element 108 has an element or structure that optically acts on light emitted from the pixel portion 106. That is, the function of suppressing light that enters the first substrate 102 from the pixel portion 106 and is emitted to the atmosphere side (outside) from being reflected at the interface between the first substrate 102 and the atmosphere and becoming lost light. Have. In other words, the optical element 108 has a function of refracting light emitted from the pixel and converting the optical path. For example, the optical element 108 has an uneven structure on one surface of the first substrate 102. The uneven structure may have a periodic pattern in which convex portions and / or concave portions are regularly arranged.

  The optical element 108 has a concavo-convex structure formed by convex portions and / or concave portions that are densely arranged at intervals of several tens of micrometers to several hundreds of micrometers on one surface of the first substrate 102. . Each convex portion or concave portion functions as a lens and has a characteristic of refracting incident light.

  In relation to the opposing pixel portion 106, at least one individual convex portion and / or concave portion in the optical element 108 may be provided in one pixel, and preferably a plurality of one convex portion and one concave portion are provided for one pixel. Should just be provided.

  An example of the optical element 108 is a microlens array. The surface of the microlens array preferably has a spherical or aspherical shape, so that a minute uneven structure is formed. Another example is a lenticular lens, and similarly, the lens surface preferably has a spherical or aspherical form. As yet another form, the optical element 108 may have a moth-eye structure. The moth-eye structure preferably has a concavo-convex structure of several hundred nanometers and has a gentle refractive index distribution.

  In the case of the top emission type, glass or a resin material is used because the first substrate 102 needs to have translucency. When the optical element 108 is provided on the first substrate 102, it is preferable to use a resin material from the viewpoints of workability and moldability. Examples of the resin material having excellent translucency include a resin material selected from polybenzoxazole, polyamideimide having an alicyclic structure, polyimide having an alicyclic structure, polyamide, and poly (p-xylylene). The thing is preferable and these resin materials may be included independently and multiple types may be combined. For example, when the first substrate 102 is formed of a polyimide resin, a polyamic acid (including a partially imidized polyamic acid) which is a polyimide precursor or a solution containing a soluble polyimide is used as the support substrate 152. It can be formed by coating and baking.

  A configuration of the pixel portion 106 will be described with reference to FIG. FIG. 2 is a cross-sectional view illustrating the configuration of the pixel 120 in the pixel portion 106. The pixel 120 includes an organic EL element 122 and a transistor 132. The organic EL element 122 has a configuration in which an organic EL layer 126 and a common electrode 128 are stacked on a pixel electrode 124. The peripheral edge of the pixel electrode 124 is covered with the bank layer 130, and the organic EL layer 126 is provided from the upper surface of the pixel electrode 124 to the bank layer 130. In addition, a sealing film 142 may be provided on the upper surface side of the organic EL element 122. The sealing film 142 is provided so as to cover a substantially front surface of the pixel portion 106.

  The organic EL layer 126 can be formed using a low molecular weight or high molecular weight organic material. In the case where a low molecular weight organic material is used for the organic EL layer 126, a carrier transport layer such as a hole transport layer or an electron transport layer is provided so as to sandwich the light emitting layer in addition to a light emitting layer containing a light emitting organic material. It may be. Further, the organic EL layer 126 may emit red (R), green (G), and blue (B) colors, or may emit white light. When the organic EL layer 126 emits white light, color display can be performed in combination with a color filter.

  In this embodiment, since it has a top emission type pixel configuration, it is preferable that the configuration of the organic EL element 122 is such that the common electrode 128 is translucent and the pixel electrode 124 is provided with a light reflecting surface. Since the light emission of the organic EL layer 126 is emitted in all directions of 4π in terms of solid angles, the light emitted to the first substrate 102 side is at least a component of light emitted directly from the organic EL layer 126. , Light components reflected by the pixel electrode 124 and emitted to the first substrate 102 side are mixed. In any case, the light emitted from the organic EL layer 126 enters the first substrate 102 at various angles.

  The common electrode 128 is applied with a common potential to a plurality of pixels, and the pixel electrode 124 is applied with an individual potential for each pixel, and the current flowing through the organic EL element 122 is controlled. The potential of the pixel electrode 124 is controlled by the transistor 132.

  The transistor 132 is a field effect transistor in which a semiconductor layer 134 and a gate electrode 138 are insulated by a gate insulating layer 136. Specifically, a thin film transistor in which a channel is formed in the thin semiconductor layer 134 is employed. An interlayer insulating layer 144 is preferably provided between the transistor 132 and the organic EL element 122, and the pixel electrode 124 is provided on the interlayer insulating layer 144, and the source / drain electrode 140 is connected via a contact hole. Connected with.

  The optical element 108 provided on the first substrate 102 is provided so as to overlap with the organic EL element 122. The uneven structure of the optical element 108 is provided on the surface of the first substrate 102 opposite to the organic EL element 122. That is, the concavo-convex structure by the optical element 108 is provided on the outer surface of the first substrate 102. The substantial light emitting region in the pixel 120 is in a region where the pixel electrode 124, the organic EL layer 126, and the common electrode 128 overlap, and in FIG. 2, a plurality of convex portions by the optical element 108 are arranged in this region. Yes. The surface of the convex portion preferably has a spherical or aspherical curved surface shape, and the light extraction efficiency is enhanced by such a form of the optical element 108.

  As described above, the light emitted from the organic EL element 122 not only enters the first substrate 102 perpendicularly but also enters the first substrate 102 at various angles. When the first substrate 102 is a resin material, the refractive index is larger than the refractive index of air, so refraction at the interface between the first substrate 102 and the atmosphere becomes a problem. For example, when the first substrate 102 is a resin material having a refractive index of about 1.6, it is higher than the refractive index of air (n = 1.0). The reflected light will be totally reflected. However, by providing the optical element 108 on the first substrate 102 and providing a concavo-convex structure on the surface on the atmosphere side, total reflection at this interface can be reduced.

  For example, when the optical element 108 is provided with a spherical or aspherical convex portion on the surface of the first substrate 102, the convex portion acts as a lens. Total reflection at the interface between the substrate and the atmosphere can be suppressed. Temporarily, the light reflected at this interface and guided through the first substrate 102 is also irregularly reflected by the action of the optical element 108 and can be emitted to the atmosphere side. By such an action by the optical element 108, the extraction efficiency of the light emitted from the organic EL element 122 can be increased.

  As shown in FIG. 2, the optical element 108 is integrated with the first substrate 102. In other words, the optical element 108 is included in the form of the first substrate 102. In the present embodiment, the image display device is thinned by integrating the optical element 108 and the first substrate 102.

  When the organic EL element 122 emits white light, the first substrate 102 may be provided with a light shielding layer 146, a color filter layer 148, and an overcoat layer 150. With this configuration, color display is possible.

  The image display apparatus 100 according to the present embodiment is provided with an optical element integrated with a sealing substrate on the light emission surface side (display screen side) from the pixel unit 106, thereby reducing the thickness of the light. It is possible to increase the extraction efficiency. Next, a method for manufacturing such an image display device will be described.

<Manufacturing method>
(Overall flow of manufacturing process)
An outline of a method for manufacturing an image display device according to an embodiment of the present invention will be described with reference to FIG. FIG. 3 is a flowchart illustrating an example of the manufacturing process of the image display device according to the present embodiment.

  The manufacturing process of the image display device includes a process of manufacturing a first substrate having an optical element, and a process of manufacturing a second substrate on which a pixel portion is formed. Then, when the first substrate and the second substrate are ready, a step of bonding the two substrates is performed.

  Since the first substrate is manufactured on the support substrate, it is necessary to prepare the support substrate (S201). The supporting substrate is made of glass, ceramics, or metal, and forms a mold structure for making an optical element on the surface. The mold structure for forming the optical element can be formed by a photolithography method, a nanoimprint method, or the like.

  Next, a resin material is applied on the support substrate provided with the mold structure (S202). The resin material is applied so as to fill the mold structure and be flat on the upper surface side of the support substrate. Then, the resin material is cured to form the first substrate (S203). At this stage, the first substrate is held on the support substrate.

  A light shielding layer is formed on the first substrate as necessary (S204), and a color filter layer is formed (S205). The light shielding layer and the color filter layer are provided when performing color display in the case where the light emission of the organic EL element provided in the pixel is white light.

  Then, when the first substrate and the second substrate are bonded together, a filler is applied on the first substrate (S206). In addition, it is preferable to form a seal pattern on the outer periphery of the first substrate before applying the filler.

  The manufacturing process of the second substrate includes a step of forming an element such as a transistor necessary for forming a pixel circuit, and a step of forming an organic EL element of each pixel. First, a pixel circuit is formed on the second substrate (S211). At this time, a scanning line driving circuit, a video signal line driving circuit, an input terminal portion, and the like are also formed as necessary. Each element such as a transistor and a capacitor constituting the pixel circuit is manufactured by repeatedly stacking a thin film of a semiconductor, an insulator, and a metal and patterning by a photolithography method.

  A pixel portion is formed on a circuit element layer in which a pixel circuit or the like is formed. In order to form the organic EL element of each pixel, a pixel electrode electrically connected to the pixel circuit is formed (S212). The pixel electrode is formed on the interlayer insulating layer in which the transistor is embedded. Next, a bank layer covering the peripheral edge of the pixel electrode is formed (S213). The pixel electrode is formed for each pixel, and the area of each pixel is demarcated by surrounding the periphery with a bank layer. Then, an organic EL layer is formed on the pixel electrode (S214), and a common electrode is further formed (S215). A sealing film is formed on the common electrode with a silicon nitride film or the like (S216). Through such steps, a pixel circuit and a pixel portion can be formed on the second substrate.

  When the first substrate and the second substrate are prepared, the two substrates are opposed to each other (S221), and then the filler is cured (S222). Thereby, the first substrate and the second substrate are fixed. Thus, when the first substrate and the second substrate are bonded together, the support substrate is separated from the first substrate (S223). Since the support substrate removed from the first substrate can be reused, it can be applied to the process of manufacturing the first substrate using the support substrate (S202).

  Next, details of the manufacturing process of the image display device according to the present embodiment will be described with reference to FIGS. 4, 5, and 6.

(Manufacture of the first substrate)
The details of the manufacturing process of the first substrate 102 will be described with reference to FIG. FIG. 4A shows a step of preparing the support substrate 152. As the support substrate 152, a glass substrate or a ceramic substrate can be used, and a metal substrate may be used. On the surface of the support substrate 152, a mold structure 154 serving as a prototype of the optical element is formed. For example, when the optical element has a spherical or aspherical convex lens shape, the mold structure 154 formed on the support substrate 152 is formed in a form in which a plurality of concave openings are adjacent to each other.

  The mold structure 154 can be formed on the surface of the support substrate 152 by forming an etching mask on the surface and etching the surface of the support substrate 152 using the mask. On the other hand, when the optical element has the shape of a spherical lens or an aspherical concave lens, a convex protrusion is formed on the surface of the support substrate 152, contrary to the concave opening shown in FIG. Such a mold structure can be produced by etching using photolithography or nanoimprint technology.

  FIG. 4B shows a step of forming the first substrate 102 on the support substrate 152. First, a resin material is applied to the surface of the support substrate 152 on which the mold structure 154 serving as a prototype of the optical element is formed. The resin material is embedded so as to embed a mold structure serving as a prototype of the optical element and to have a flat surface. As the resin material, a polymer compound containing an imide bond can be used, and a polyimide resin can be preferably used. After applying the resin material, a curing process is performed. If it is a thermosetting resin material, heat treatment is performed, and if it is a photocurable resin material, light irradiation treatment is performed. In this way, the first substrate 102 is formed.

  FIG. 4C shows a stage in which a light shielding layer 146, a color filter layer 148, and an overcoat layer 150 are provided over the first substrate 102 as necessary. The color filter layer 148 is arranged in accordance with the arrangement of the pixels on the second substrate, and the light shielding layer 146 is provided so as to surround the pixels.

  FIG. 4D shows a step of providing a filler 118 on the upper surface of the first substrate 102. The filler 118 is provided at a stage before being bonded to the second substrate 104. The filler 118 has fluidity at this stage, and a necessary amount is applied onto the first substrate 102.

(Manufacture of second substrate)
A pixel portion 106 is formed on the second substrate 104. The pixel portion 106 includes a plurality of pixels. FIG. 5 shows an aspect in which the second substrate 104 is provided with each pixel of the red pixel 120r, the green pixel 120g, and the blue pixel 120b. Each pixel is provided with an organic EL element 122. The organic EL element 122 is formed by stacking a pixel electrode 124, an organic EL layer 126, and a common electrode 128. The outer periphery of the pixel electrode 124 is covered with a bank layer 130, and the organic EL element 122 is covered with a sealing film 142.

  In the pixel portion 106, an organic EL element that emits light corresponding to each color is provided in each pixel, whereby the red pixel 120r, the green pixel 120g, and the blue pixel 120b can be obtained. Alternatively, the light emission of the organic EL element 122 may be white and combined with a color filter layer provided on the first substrate, whereby the red pixel 120r, the green pixel 120g, and the blue pixel 120b may be formed.

  FIG. 5 shows an example when the organic EL element 122 emits white light. In this case, the organic EL layer 126 can be provided in common for each pixel. A circuit element layer 158 in which a transistor is formed may be provided below the organic EL element 122. These details are as described with reference to FIG.

(Lamination process)
FIG. 6A shows a step of bonding the first substrate 102 and the second substrate 104 together. At this time, the first substrate 102 is bonded to the second substrate 104 while being fixed to the support substrate 152. A filler 118 is provided between the first substrate 102 and the second substrate 104. Since the first substrate 102 is held by the support substrate 152 until the bonding step, the flat shape is maintained even when the first substrate 102 is a thin resin layer, and the alignment accuracy with the second substrate 104 is improved. Can be increased.

  FIG. 6B shows a step of separating the support substrate 152 from the first substrate 102. Since the first substrate 102 is bonded to the support substrate 152 with a certain degree of strength, a process of weakening the adhesive strength at the interface between the first substrate 102 and the support substrate 152 is performed by a laser irradiation process or the like, and the support substrate 152 is It is made easy to peel from the substrate 102. In addition, a release material may be provided on the surface of the support substrate in advance. The optical element 108 is integrally formed on the first substrate 102 from which the support substrate 152 has been peeled off. The optical element 108 has a concavo-convex structure surface on the outer surface of the first substrate 102.

  In the present embodiment, the first substrate 102 hits the surface on which light emitted from each pixel is emitted, and the light extraction efficiency can be increased by the action of the optical element 108. Since the optical element 108 is formed integrally with the first substrate 102, the thickness of the image display device does not increase. Since it is not necessary to provide a new layer for forming the optical element 108, a new process is not required. Since the support substrate peeled off from the first substrate 102 retains the mold structure as an original optical element, the support substrate 152 can be reused. That is, once the support substrate 152 is manufactured, it can be used a plurality of times, so that the member cost can be reduced and the productivity can be improved.

  As described above, according to the present embodiment, it is possible to provide an image display device that is thin and can improve the extraction efficiency of light emitted from the pixels. Further, it is possible to provide an image display device capable of improving the light extraction efficiency by a rational manufacturing process.

(Modification)
In the step of forming the mold structure 154 as a prototype of the optical element on the support substrate 152, a marker may be produced at the same time. FIG. 7A illustrates an example of a support substrate 152 provided with a marker 156. When the support substrate 152 is etched to form the mold structure 154, the marker 156 can be similarly manufactured by etching the support substrate 152.

  The position where the marker 156 is formed is arbitrary, but it is preferable that the marker 156 be formed outside the mold structure 154. Since the marker 156 is formed in the same manner as the mold structure 154, when the mold structure 154 is a concave opening, the marker 156 is also formed as a concave groove. Then, as shown in FIG. 7B, when the first substrate 102 is formed on the support substrate 152, the resin material is also filled in the concave groove of the marker 156 portion. Since it is refracted, it can be optically recognized by a camera or the like.

  The marker 156 provided on the support substrate 152 can be used as an alignment marker when forming the light shielding layer 146 and the color filter layer 148. It can also be used as an alignment marker when the first substrate 102 and the second substrate 104 are bonded together.

  As described above, when the mold structure 154 is formed on the support substrate 152, the marker 156 is manufactured at the same time, so that when the light shielding layer 146 and the color filter layer 148 are formed on the first substrate 102, a marker is newly added. This eliminates the need to form and improves productivity.

[Second Embodiment]
In the present embodiment, an image display device in which the first substrate on which the optical element is provided is different from that of the first embodiment will be described.

  FIG. 8A illustrates a state where the first substrate 102b is provided on the support substrate 152b. The support substrate 152b is a flat substrate, and the first substrate 102b including the optical element 108 is provided thereon. As for the 1st board | substrate 102b, the uneven structure by an optical element has appeared in the surface on the opposite side to the support substrate 152b. For example, when the optical element has a form like a microlens array, a spherical or aspherical projection is provided on the surface of the first substrate 102b. The optical element 108 may be a lenticular lens as well as a microlens array, or may have a moth-eye structure.

  As described in the first embodiment, the first substrate 102 having such a concavo-convex structure forms the first substrate 102 with the support substrate 152 on which the mold structure 154 serving as a prototype of the optical element is formed (FIG. 4 (A) and (B)), the first substrate 102 peeled from the support substrate 152 is provided on the support substrate 152b as shown in FIG. 8A. Alternatively, a resin layer may be provided over the support substrate 152b, and a concavo-convex structure serving as the optical element 108 may be formed on the resin layer by a nannoimprint method to form the first substrate 102b.

  FIG. 8B shows a step of providing a planarization layer 160 over the first substrate 102. The planarization layer 160 is preferably provided so that the concavo-convex structure of the first substrate 102b is embedded and the surface becomes flat. The planarization layer 160 and the first substrate 102b are preferably formed of materials having different refractive indexes. In this case, it is preferable that the refractive index of the planarization layer 160 be larger than the refractive index of the first substrate 102b. The planarization layer 160 can be formed using a resin material, and a polyimide-based, acrylic-based, or epoxy-based resin material can be used as the resin material.

  As shown in FIG. 8C, a light shielding layer 146, a color filter layer 148, and an overcoat layer 150 can be provided on the upper surface of the first substrate 102b as needed. Then, as shown in FIG. 8D, a filler 118 is provided on the upper surface of the first substrate 102b.

  FIG. 9A shows a step of bonding the first substrate 102b and the second substrate 104 together. The first substrate 102b is held by the support substrate 152b until the bonding stage. Accordingly, even when the first substrate 102b is a thin resin layer, the flat shape can be maintained and the second substrate 104 can be bonded with high accuracy.

  FIG. 9B shows a step of separating the first substrate 102b from the support substrate 152b. The support substrate 152b can be peeled from the first substrate 102b by performing laser irradiation processing or the like to change the interface of the first substrate 102b and weaken the adhesive strength.

  The uneven structure in the first substrate 102b faces inward, that is, toward the second substrate 104, and the interface between the first substrate 102b and the planarization layer 160 is uneven by the optical element 108. When the refractive index of the planarizing layer 160 is larger than the refractive index of the first substrate 102b, the light incident on the interface from the pixel side is suppressed from total reflection, and the optical path changes due to the difference in refractive index. With such a configuration, light emitted from the organic EL element 122 in the pixel is incident at various angles when entering the interface between the first substrate 102b and the atmosphere, so that the loss component due to total reflection is reduced. , The light extraction efficiency can be increased.

  In the image display device according to the present embodiment, the planarization layer 160 is added to the first substrate 102b. However, since the planarization layer 160 only needs to embed the concavo-convex structure by the optical element 108, the thickness increase is slight. It is. Therefore, as in the first embodiment, it is possible to obtain an image display device that is improved in light extraction efficiency and reduced in thickness.

  Note that the configuration of this embodiment can be combined with the configurations of the other embodiments as appropriate. For example, as described with reference to FIG. 7 in the first embodiment, if the marker is formed on the first substrate 102b, the light shielding layer 146 and the color filter layer 148 are formed using the marker. It can be used as an alignment marker.

[Third Embodiment]
This embodiment shows an aspect of a bottom emission type image display device that emits light emitted from a pixel to the second substrate side. In the bottom emission type image display device, an optical element is provided on the second substrate side which is a light emission side.

  The second substrate 104c is formed on the support substrate 152 as described in the first embodiment. As shown in FIGS. 4A and 4B, the second substrate 104c is formed on a support substrate 152 on which a mold structure serving as a prototype of the optical element is formed. As shown in FIG. 10A, a circuit element layer 158, a pixel electrode 124, a bank layer 130, an organic EL layer 126, a common electrode 128, and a sealing film 142 are provided on the second substrate 104c.

  As shown in FIG. 10A, such a second substrate 104c is bonded to the first substrate 102c provided with the light shielding layer 146, the color filter layer 148, and the overcoat layer 150 with a filler 118 interposed therebetween. . Then, as shown in FIG. 10B, an image display device in which the optical element 108 is integrally formed on the second substrate 104c can be obtained by peeling the support substrate 152 from the second substrate 104c.

  In the image display device of the present embodiment, the light emitted from each pixel is emitted to the second substrate 104c side. At this time, since the optical element 108 is provided on the second substrate 104c, the light extraction efficiency can be increased as in the first embodiment. In addition, since the optical element 108 is integrated with the second substrate 104c, the image display device can be thinned.

  Note that the configuration of this embodiment can be combined with the configurations of the other embodiments as appropriate. For example, as described with reference to FIG. 7 in the first embodiment, if the marker is formed on the first substrate 102b, the marker is replaced by the transistor 132, the pixel electrode 124, the bank layer 130, and the like. It can be used as an alignment marker when forming.

DESCRIPTION OF SYMBOLS 100 ... Image display apparatus, 102 ... 1st board | substrate, 104 ... 2nd board | substrate, 106 ... Pixel part, 108 ... Optical element, 110 ... Scanning line drive circuit, 112 ...・ Video signal line drive circuit, 114... Input terminal section, 116... Sealing material, 118... Filling material, 120. 126 ... Organic EL layer, 128 ... Common electrode, 130 ... Bank layer, 132 ... Transistor, 134 ... Semiconductor layer, 136 ... Gate insulating layer, 138 ... Gate electrode, 140 ... source / drain electrodes, 142 ... sealing film, 144 ... interlayer insulating layer, 146 ... light shielding layer, 148 ... color filter layer, 150 ... overcoat layer, 152. ..Support substrate, 154 ... Mo De structure, 156 ... markers, 158 ... circuit element layer, 160 ... planarization layer.

Claims (15)

A method for manufacturing an image display device in which an optical element is provided on a pixel portion provided with a plurality of pixels,
Applying a resin material on the surface of a support substrate provided with a mold structure as a prototype of the optical element to embed the mold structure and forming a first substrate having a substantially flat upper surface;
A region in which the first substrate and the second substrate provided on the support substrate are opposed to each other, the pixel portion is disposed between the first substrate and the second substrate, and the mold structure is provided. Pasted to overlap with
A method of manufacturing an image display device, wherein the first substrate is released from the support substrate.   The method for manufacturing an image display device according to claim 1, wherein a light shielding layer and / or a color filter layer is formed on the first substrate in accordance with the arrangement of the plurality of pixels.   3. The image display apparatus according to claim 2, wherein the mold structure is formed on one surface of the support substrate, and an alignment mark for forming the light shielding layer and / or the color filter layer is formed. Method.   The method for manufacturing an image display device according to claim 1, wherein the support substrate after releasing the first substrate is reused.   The method for manufacturing an image display device according to claim 1, wherein the mold structure provided on the surface of the support substrate is a regular concave structure or a convex structure.   6. The method of manufacturing an image display device according to claim 5, wherein the mold structure provided on the surface of the support substrate is a prototype of a microlens array.   6. The method of manufacturing an image display device according to claim 5, wherein the mold structure provided on the surface of the support substrate is a prototype of a lenticular lens.   6. The method for manufacturing an image display device according to claim 5, wherein the mold structure provided on the surface of the support substrate is a moth-eye structure prototype.   The method for manufacturing an image display device according to claim 1, wherein an organic electroluminescence element is formed in the pixel portion.   A pixel array in which a plurality of pixels are arranged is disposed between a pair of substrates, and a non-planar surface structure is provided on a side of the pair of substrates on which the output light from the pixel array is emitted. An image display device, wherein optical elements are integrally formed.   The image display device according to claim 10, wherein a surface structure of the optical element is a regular concave structure or a convex structure.   The image display device according to claim 11, wherein the optical element is a microlens array.   The image display device according to claim 11, wherein the optical element is a lenticular lens.   The image display apparatus according to claim 11, wherein the optical element is an element having a moth-eye structure. The image display apparatus according to claim 10, wherein an organic electroluminescence element is provided in each of the plurality of pixels.

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