JP2007248494A - Microlens substrate and method of manufacturing same, electrooptical device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily manufacture microlenses as meniscus lenses. <P>SOLUTION: The microlens substrate includes a transparent member 210 in which a plurality of lens formation parts 212 are formed and a first transparent material film 230 having first lens curved surfaces 500a of the microlenses 500 on the joint surfaces with the lens formation parts 212 corresponding to each of the plurality of lens formation parts 212, second lens curved surfaces 500b of the microlenses 500 formed by transferring the shapes of the first lens curved surfaces 500a and a refractive index different from that of the transparent member 210. Furthermore, the microlens substrate is provided with a second transparent material film 200 formed by being joined with the second lens curved surfaces 500b in an upper layer from the first transparent material film 230 and having a refractive index different from that of the first transparent material film 230. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a microlens substrate used in an electro-optical device such as a liquid crystal device and a manufacturing method thereof, an electro-optical device including the micro-lens substrate, and an electronic apparatus such as a projector including the electro-optical device. In the technical field.

  This type of microlens substrate is provided as a counter substrate in a liquid crystal device constituting a light valve in a projector, for example. On such a microlens substrate, for example, a microlens having a spherical lens curved surface is formed corresponding to each pixel. In the liquid crystal device, the microlens substrate is used as a counter substrate, and the microlens substrate is disposed so as to face each pixel electrode with respect to the TFT array substrate in which the pixel electrode is formed. For example, a liquid crystal is sandwiched as an electro-optical material.

  In such a liquid crystal device, light such as projection light incident on the liquid crystal device is refracted and condensed by a microlens and incident on each pixel, thereby improving the light utilization efficiency and providing a bright display. Realized.

  However, in this case, in each pixel, the light traveling direction is changed by the refraction of the light by the microlens, so that the light amount actually contributing to the display is reduced with respect to the light amount collected by the microlens. As a result, defects such as a loss of light and a decrease in contrast occur. Further, in each pixel, light is concentrated and irradiated at one place by condensing by the microlens, so that there is a possibility that the liquid crystal, the conductive film constituting the pixel electrode, and the like are deteriorated by heating.

  In order to correct such various problems in a well-balanced manner, Patent Document 1 discloses a technique for forming each microlens as a meniscus lens on a microlens substrate. The “meniscus lens” refers to a lens having a structure in which two types of lens curved surfaces on the light incident side and light exit side are formed in a concave shape or a convex shape, respectively.

JP 2002-6114 A

  However, according to the configuration of the microlens substrate disclosed in Patent Document 1, in the manufacturing process, the process for forming two types of lens curved surfaces of the meniscus lens becomes complicated, and there is a problem that the manufacturing cost increases. As a result, it is difficult to actually manufacture a microlens substrate.

  The present invention has been made in view of the above-described problems. A microlens substrate capable of easily manufacturing a microlens as a meniscus lens, a manufacturing method thereof, an electro-optical device including the microlens substrate, and the like It is an object to provide an electronic apparatus including such an electro-optical device.

  In order to solve the above problems, the microlens substrate of the present invention includes a transparent member in which a plurality of lens forming portions each defining the first lens curved surface of the microlens are arranged in a predetermined pattern, and the plurality of lens forming portions. The first lens curved surface is formed on a surface opposite to the first lens curved surface, and has a first lens curved surface on a joint surface with each of the plurality of lens forming portions. A first transparent material film having a second lens curved surface of the microlens to which is transferred and having a refractive index different from that of the transparent member; and the second lens curved surface; and the first lens And a second transparent material film having a different refractive index from the transparent material film.

  According to the microlens substrate of the present invention, in the first transparent material film, a microlens is formed as a meniscus lens having a first lens curved surface and a second lens curved surface corresponding to each of the plurality of lens forming portions. Is done.

  Therefore, the light incident on the microlens substrate can be emitted as parallel light by each microlens. That is, in each microlens, the light incident on one of the first and second lens curved surfaces is refracted and collected, and then is refracted again by being emitted from the other lens curved surface to be parallel light. Is emitted as Thereby, in the microlens substrate of the present invention, it is possible to improve the light utilization efficiency and prevent the light emitted from each microlens from being irradiated locally.

  Here, in the microlens substrate of the present invention, the first lens curved surface of each microlens is formed by each lens forming portion and the first transparent material film having a refractive index different from that of the transparent member bonded thereto. It is prescribed. Therefore, by adjusting the shape of each of the plurality of lens forming portions, the radius of curvature of the first lens curved surface can be adjusted.

  Further, the second lens curved surface of each microlens has a refractive index different from that of the first transparent material film on the surface opposite to the first lens curved surface of the first transparent material film. And a transparent material film. Then, on the surface of the first transparent material film opposite to the first lens curved surface, the second lens curved surface to which the first lens curved surface is transferred is transferred by transferring the surface shape of the lens forming portion. It is formed. Therefore, the shape of the second lens curved surface reflects the shape of the first lens curved surface. The term “transfer” as used herein means that the uneven shape formed based on the presence of each lens forming portion on the surface of the transparent member that is bonded to the first transparent material film is the first transparent material. It means that the material film is propagated to the surface opposite to the joint surface with the transparent member.

  Accordingly, by adjusting the shape of each of the plurality of lens forming portions as described above, the shape of the first lens curved surface, and in addition to this, the shape of the second lens curved surface can also be adjusted. Therefore, at the time of manufacturing the microlens substrate of the present invention, other than forming the lens forming portion that defines the first lens curved surface on the transparent member as in the technique disclosed in Patent Document 1, for example, There is no need to prepare a member and perform a process for defining the second lens curved surface. As described above, since the processing for defining the second lens curved surface is performed separately from the processing for defining the first lens curved surface, a design error or the like occurs, resulting in a manufacturing process. There is a risk of complications. On the other hand, according to the configuration of the microlens substrate of the present invention, such complexity can be avoided.

  In addition, since the first and second transparent material films are sequentially laminated and covered on the surfaces of the plurality of lens forming portions, in the second transparent material film, the bonding surface with the first transparent material film and On the opposite surface, the uneven shape due to the presence of the plurality of lens forming portions can be more relaxed than the surface on the side where the plurality of lens forming portions in the transparent member are formed. Therefore, it is possible to obtain good flatness on the surface of the second transparent material film without performing a flattening process.

  Therefore, according to the microlens substrate of the present invention, each microlens can be formed as a meniscus lens by a simpler manufacturing process.

  In one aspect of the microlens substrate of the present invention, in the first transparent material film, the second lens curved surface is formed with a curvature radius different from that of the first lens curved surface.

  According to this aspect, at the time of manufacturing the microlens substrate, the first transparent material film is, for example, a sheet-like or film-like transparent resin film disposed on the upper layer side of the transparent member and, for example, pressed to form each lens forming portion. And bonded to a transparent member. Alternatively, for example, the first transparent material film may be formed by a spin coating method, a PVD (Physical Vapor Deposition) method, or the like. At this time, mechanical properties such as Young's modulus and physical properties such as viscosity of the transparent material forming the first transparent material film are selectively adjusted, and manufacturing conditions such as coating conditions and film forming conditions are combined with these. Or further adjusting the film thickness. Thereby, according to this aspect, about each microlens, the curvature radius of the 2nd lens curved surface is made smaller than the 1st lens curved surface, or it is enlarged contrary to this, and it adjusts uniquely. be able to.

  In another aspect of the microlens substrate of the present invention, each of the plurality of lens forming portions is formed as a concave portion.

  According to this aspect, in the first transparent material film, the first lens curved surface of each microlens is formed as a concave lens curved surface that is recessed concavely with respect to the surface of the transparent member. By transferring the shape of the first lens curved surface to the surface opposite to the curved surface, the second lens curved surface is also concave with respect to the surface to be joined to the second lens curved surface of the second transparent material film. It can be formed as a concave lens curved surface that is recessed.

  In an aspect in which each lens forming portion is formed as a recess, the first transparent material film is formed of a first transparent material having a refractive index larger than that of the transparent member, and the second transparent material film. May be formed of a second transparent material having a smaller refractive index than that of the first transparent material film.

  If comprised in this way, when each lens formation part is formed as a recessed part in a transparent member, it will inject into the transparent member of a microlens board | substrate, and will further inject into a 1st transparent material film from each lens formation part Can be emitted as parallel light by each microlens.

  In another aspect of the microlens substrate of the present invention, each of the plurality of lens forming portions is formed as a convex portion.

  According to this aspect, in the first transparent material film, the first lens curved surface of each microlens is formed as a convex lens curved surface projecting convexly with respect to the surface of the transparent member, and the second The lens curved surface can also be formed as a convex lens curved surface protruding in a convex shape with respect to the surface joined to the second lens curved surface of the second transparent material film.

  In an aspect in which each lens forming portion is formed as a convex portion, the first transparent material film is formed of a first transparent material having a refractive index smaller than that of the transparent member, and the second transparent material. The film may be configured to be formed of a second transparent material having a higher refractive index than the first transparent material film.

  If comprised in this way, when each lens formation part is formed as a convex part in a transparent member, it will inject into the transparent member of a micro lens board | substrate, and will inject into a 1st transparent material film | membrane from each lens formation part further Light can be emitted as parallel light by each microlens.

  In another aspect of the microlens substrate of the present invention, the second transparent material film has a surface subjected to a planarization process on the side opposite to the side bonded to the second lens curved surface.

  According to this aspect, at the time of manufacturing the microlens substrate, the second transparent material film has a surface opposite to the surface of the first transparent material film opposite to the side to be bonded to the second lens curved surface of each microlens. For example, a planarization process such as a CMP (Chemical Mechanical Polishing) process is performed. As a result, a surface having better flatness can be obtained in the second transparent material film, and thus a more accurate light collecting function can be realized by the microlens formed under the surface having high flatness. .

  In order to solve the above problems, the electro-optical device of the present invention includes the above-described microlens substrate of the present invention (including various aspects thereof), a display electrode facing the microlens, and the display electrode. Electrically connected wiring or electronic elements.

  According to the electro-optical device of the present invention, since the above-described microlens substrate of the present invention is provided, light such as projection light incident on the electro-optical device is collected by each microlens as parallel light to each pixel. It becomes possible to make it enter.

  Therefore, in each pixel, the traveling direction of light is excessively changed by the microlens, and it is possible to prevent the decrease in the amount of light that actually contributes to display and to effectively use the light collected by the microlens. . In addition, in each pixel, local irradiation of light collected by the microlens can be prevented. Therefore, it is possible to prevent deterioration of electro-optical materials such as liquid crystal and display electrodes while preventing loss of light and preventing a decrease in contrast. Therefore, the electro-optical device of the present invention can perform high-quality image display.

  In the electro-optical device of the present invention, by adjusting the thickness of the lens, the radius of curvature of each of the first and second lens curved surfaces, and the like for each microlens of the microlens substrate according to the pixel aperture ratio, It is possible to obtain a uniform light distribution in each pixel and within the pixel.

  In order to solve the above problems, an electronic apparatus according to the present invention includes the above-described electro-optical device according to the present invention.

  Since the electronic apparatus of the present invention includes the above-described electro-optical device of the present invention, a projection display device, a television, a mobile phone, an electronic notebook, a word processor, a view capable of performing high-quality image display. Various electronic devices such as a finder type or a monitor direct-view type video tape recorder, a workstation, a videophone, a POS terminal, and a touch panel can be realized. Further, as the electronic apparatus of the present invention, for example, an electrophoretic device such as electronic paper, a display device using an electron emission device (Field Emission Display and Conduction Electron-Emitter Display), or the like can be realized.

  In order to solve the above-described problem, the method of manufacturing a microlens substrate of the present invention includes a first step of forming a plurality of lens forming portions each defining a first lens curved surface of a microlens in a transparent pattern on a transparent member. Each of the plurality of lens forming portions of the first transparent material film by forming a first transparent material film that is joined to each of the plurality of lens forming portions and has a refractive index different from that of the transparent member. The second lens curved surface of the microlens is formed by forming the first lens curved surface on the cementing surface and transferring the shape of the first lens curved surface to the surface opposite to the first lens curved surface. And a third step of forming a second transparent material film that is bonded to the second lens curved surface and has a refractive index different from that of the first transparent material film.

  According to the method for manufacturing a microlens substrate of the present invention, each microlens can be formed as a meniscus lens by a simpler manufacturing process, like the microlens substrate of the present invention described above.

  Such an operation and other advantages of the present invention will become apparent from the embodiments described below.

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

<1: Microlens substrate>
First, the microlens substrate of the present invention will be described with reference to FIGS.

  Here, FIG. 1A is a schematic perspective view of a microlens substrate, and FIG. 1B is a schematic perspective view showing a configuration including the A-A ′ cross-section portion of FIG. FIG. 2A is a partially enlarged plan view showing a portion related to four microlenses in the microlens substrate, and FIG. 2B is an enlarged cross-sectional view showing the configuration of the microlens. is there. In FIGS. 1 and 2, the scale of each member is made different for each member and each drawing so that each member can be recognized on the drawing. This is the same for each figure after FIG. 3 described later.

  As shown in FIG. 1A, the microlens substrate 20 of the present embodiment includes a transparent substrate 210 that is an example of a “transparent member” according to the present invention made of, for example, a glass plate, a quartz plate, and the like, and the transparent substrate 210. And a second transparent material film 200 that sandwiches the first transparent material film 230 therebetween.

  As shown in FIG. 1B, in the present embodiment, in the microlens substrate 20, in the lens forming region 20a, a large number of microlenses 500 that are planarly arranged in a matrix are formed as meniscus lenses. .

  More specifically, in FIG. 1B or FIG. 2B, in the transparent substrate 210, in the lens forming region 20a, a large number of concave depressions, that is, concave portions 212 are dug in an array. In FIG. 2B, the configuration of the cross-sectional portion of the microlens substrate 20 is shown in a more simplified manner.

  On the transparent substrate 210, the first transparent material film 230 is joined to each recess 212 and is formed of a first transparent material having a higher refractive index than the transparent substrate 210. As a result, in the first transparent material film 230, the first lens curved surface 500a of the microlens 500 is defined as a concave lens curved surface by the joint surface with the transparent substrate 210 and each concave portion 212. For example, the transparent substrate 210 is formed to have a refractive index of about 1.46. Correspondingly, the first transparent material film 230 is formed of a resin such as an epoxy resin or an acrylic resin as the first transparent material. For example, the refractive index is formed from a material or a transparent material containing sulfur (S), fluorine (F), or silicon (Si) so as to have a refractive index of 1.5 to 1.65. Here, the first lens curved surface 500a defined by each recess 212 may be spherical or aspheric.

  In FIG. 2A, each recess 212 is formed so that the first lens curved surface 500a of the microlens 500 defined by the recess 212 is in contact with the first lens curved surface 500a defined by the adjacent recess 212. It may be formed so as to cross each other. If the lens curved surfaces are formed so as to intersect with each other as in the latter, each microlens 500 can have a wide effective area as a lens. Ideally, in FIG. 2A, if the four first lens curved surfaces 500 a intersect each other at the corner portion of each microlens 500, the condensing function is extended to every corner of each microlens 500. It is possible to increase the light utilization efficiency.

  In FIG. 2B, the surface shape of the first transparent material film 230 on the side opposite to the bonding surface with the transparent substrate 210 reflects the surface shape of the transparent substrate 210 where the concave portion 212 is formed. As a result, a concavo-convex shape resulting from the presence of each recess 212 is formed. As a result, in the first transparent material film 230, the shape of the first lens curved surface 500a is transferred to the surface opposite to the first lens curved surface 500a to form a concave lens curved surface. A second lens curved surface 500b is formed. That is, in the present embodiment, each microlens 500 can be formed as a meniscus lens in the first transparent material film 230.

  The second lens curved surface 500b of each microlens 500 is formed by the surface of the first transparent material film 230 and the second transparent material having a lower refractive index than that of the first transparent material film 230 bonded to the surface. It is prescribed | regulated by the 2nd transparent material film | membrane 200 formed. For example, the second transparent material film 200 is formed of, for example, a transparent resin material, silicon oxide (SiO 2), or the like as the second transparent material so that the refractive index becomes a value of 1.5 or less.

  In FIG. 2B, in this embodiment, for each microlens 500, the radius of curvature R1 of the first lens curved surface 500a and the radius of curvature R2 of the second lens curved surface 500b are the same values. Alternatively, they may be formed differently.

<2: Electro-optical device>
Next, the overall configuration of an electro-optical device according to an embodiment of the invention will be described with reference to FIGS. 3 and 4. FIG. 3 is a plan view of the TFT array substrate viewed from the above-described microlens substrate side used as a counter substrate together with each component formed thereon, and FIG. 'Cross section. Here, a TFT active matrix driving type liquid crystal device with a built-in driving circuit as an example of an electro-optical device is taken as an example.

  3 and 4, in the electro-optical device according to the present embodiment, the TFT array substrate 10 and the microlens substrate 20 used as the counter substrate are disposed to face each other. A liquid crystal layer 50 is sealed between the TFT array substrate 10 and the microlens substrate 20, and the TFT array substrate 10 and the microlens substrate 20 are sealed in a seal region positioned around the image display region 10a. The materials 52 are bonded to each other.

  The sealing material 52 is made of, for example, an ultraviolet curable resin, a thermosetting resin, or the like for bonding the two substrates, and is applied on the TFT array substrate 10 in the manufacturing process and then cured by ultraviolet irradiation, heating, or the like. It is. Further, although not shown in FIG. 3 or FIG. 4, the sealing material 52 includes a glass fiber or a glass bead for setting the distance between the TFT array substrate 10 and the microlens substrate 20 (inter-substrate gap) to a predetermined value. Of gap material. That is, the electro-optical device according to the present embodiment is suitable for a small and enlarged display for a projector light valve.

  A light-shielding frame light-shielding film 53 that defines the frame area of the image display region 10a is provided on the microlens substrate 20 side in parallel with the inside of the seal region where the sealing material 52 is disposed. However, part or all of the frame light shielding film 53 may be provided as a built-in light shielding film on the TFT array substrate 10 side.

  Of the peripheral regions located around the image display region 10 a, the data line driving circuit 101 and the external circuit connection terminal 102 are arranged on one side of the TFT array substrate 10 in the region located outside the seal region where the sealing material 52 is disposed. It is provided along. The scanning line driving circuit 104 is provided along two sides adjacent to the one side so as to be covered with the frame light shielding film 53. The two scanning line driving circuits 104 are electrically connected to each other by a plurality of wirings 105 provided along the remaining one side of the TFT array substrate 10.

  In addition, vertical conduction members 106 are disposed at the four corners of the microlens substrate 20. On the other hand, although not shown in FIG. 3 or 4, the TFT array substrate 10 is provided with vertical conduction terminals in a region facing these corner portions. As a result, electrical conduction can be established between the TFT array substrate 10 and the microlens substrate 20.

  In FIG. 4, on the TFT array substrate 10, a pixel switching TFT (Thin Film Transistor; hereinafter referred to as “TFT” as appropriate), wiring lines such as scanning lines and data lines are formed. On the pixel electrode 9a which is an example of the “display electrode”, an alignment film (not shown) is formed. In the present embodiment, the pixel switching element may be constituted by various transistors, TFD, or the like in addition to the TFT. On the other hand, a detailed configuration will be described later. On the microlens substrate 20, in addition to the counter electrode 21, a lattice-shaped or striped light-shielding film 23 and an alignment film (not shown) are formed on the uppermost layer. ing.

  The liquid crystal layer 50 is made of, for example, a liquid crystal in which one or several types of nematic liquid crystals are mixed, and takes a predetermined alignment state between the pair of alignment films.

  In addition to the data line driving circuit 101, the scanning line driving circuit 104, and the like, the image signal on the image signal line is sampled and supplied to the data line on the TFT array substrate 10 shown in FIGS. Sampling circuit, precharge circuit for supplying a precharge signal of a predetermined voltage level to a plurality of data lines in advance of an image signal, for inspecting the quality, defects, etc. of the electro-optical device during production or at the time of shipment An inspection circuit or the like may be formed.

  Next, the circuit configuration and operation of the electro-optical device configured as described above will be described with reference to FIG. FIG. 5 shows an equivalent circuit of various elements, wirings, and the like in a plurality of pixels formed in a matrix that forms the image display area of the electro-optical device.

  In FIG. 5, each of the plurality of pixels formed in a matrix that forms the image display region 10 a of the electro-optical device according to the present embodiment includes a pixel electrode 9 a and a TFT 30 for switching control of the pixel electrode 9 a. The data line 6 a formed and supplied with an image signal is electrically connected to the source of the TFT 30. The image signals S1, S2,..., Sn written to the data lines 6a may be supplied line-sequentially in this order, or may be supplied for each group to a plurality of adjacent data lines 6a. Good.

  Further, the gate electrode 3a is electrically connected to the gate of the TFT 30, and the scanning signals G1, G2,..., Gm are pulse-sequentially applied in this order to the scanning line 11a and the gate electrode 3a at a predetermined timing. It is comprised so that it may apply. The pixel electrode 9a is electrically connected to the drain of the TFT 30, and the image signal S1, S2,..., Sn supplied from the data line 6a is obtained by closing the switch of the TFT 30 as a switching element for a certain period. Write at a predetermined timing.

  Image signals S1, S2,..., Sn written in a liquid crystal as an example of an electro-optical material via the pixel electrode 9a are held for a certain period with the counter electrode 21 formed on the microlens substrate 20. Is done. The liquid crystal modulates light and enables gradation display by changing the orientation and order of the molecular assembly depending on the applied voltage level. In the normally white mode, the transmittance for incident light is reduced according to the voltage applied in units of each pixel, and in the normally black mode, the light is incident according to the voltage applied in units of each pixel. The light transmittance is increased, and light having a contrast corresponding to the image signal is emitted from the electro-optical device as a whole. Therefore, from such a display principle, in the liquid crystal device, the viewing angle (observation angle) at which the contrast ratio of the display image becomes a predetermined value is limited to a predetermined range (a value indicating this range is referred to as a “viewing angle”).

  In order to prevent the image signal held here from leaking, a storage capacitor 70 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 9a and the counter electrode. The storage capacitor 70 is provided side by side along the scanning line 11a, and includes a capacitor electrode 300 that includes a fixed potential side capacitor electrode and is fixed at a constant potential.

  A detailed configuration and function of the microlens substrate 20 provided in the above-described electro-optical device will be described with reference to FIGS. 6 is a plan view schematically showing the arrangement relationship of the opening region 700 in which the light shielding film 23 and the microlens 500 are arranged in the microlens substrate 20, and FIG. 7 shows a plurality of pixels in FIG. It is a figure which shows the structure of the cross section shown in detail, Comprising: It is sectional drawing for demonstrating the function of each micro lens 500. FIG.

  In FIG. 7, in the microlens substrate 20, a light shielding film 23 having a grid-like planar pattern as shown in FIG. 6 is formed on the second transparent material film 200. In the microlens substrate 20, a non-opening region is defined by the light shielding film 23, and a region delimited by the light shielding film 23 is an opening region 700. The light shielding film 23 is formed in a stripe shape, and the non-opening region is defined by the light shielding film 23 and various components such as the capacitor electrode 300 and the data line 6a provided on the TFT array substrate 10 side. Also good.

  Each microlens 500 is arranged so as to correspond to each pixel. More specifically, as shown in FIG. 7, in the microlens substrate 20, the microlens substrate 20 is microscopically formed in an area including at least a part of the opening area 700 and the non-opening area located around the opening area 700. A lens 500 is arranged and formed.

  In FIG. 7, the counter electrode 21 made of a transparent conductive film is formed on the second transparent material film 200 so as to cover the light shielding film 23, and the alignment film 22 is further formed on the counter electrode 21 (in FIG. 7). , Below the counter electrode 21).

  On the other hand, in FIG. 7, pixel electrodes 9 a are formed in regions corresponding to the respective opening regions 700 on the TFT array substrate 10. In addition, on the TFT array substrate 10, pixel switching TFTs 30, various wirings such as scanning lines 11 a and data lines 6 a for driving the pixel electrodes 9 a, and electronic elements such as storage capacitors 70 are formed in non-opening regions. Has been. With this configuration, the pixel aperture ratio in the electro-optical device can be maintained relatively large. Further, an alignment film 16 is provided on the pixel electrode 9a.

  In FIG. 7, the appearance of light incident on the microlens 500 is schematically shown by a one-dot chain line arrow. In the microlens substrate 20, light such as projection light incident on the transparent substrate 210 is incident on the first lens curved surface 500a in each microlens 500, and is refracted and condensed. Thereafter, the condensed light is refracted by being emitted from the second lens curved surface 500b of the microlens 500, and is emitted as parallel light. That is, in the present embodiment, parallel light can be incident on each pixel by the microlens 500.

  Here, with reference to FIG. 8, only a different point from this embodiment is demonstrated about a comparative example. FIG. 8 is a cross-sectional view showing a configuration of a cross-sectional portion corresponding to FIG. 7 for the comparative example. Also in FIG. 8, the appearance of light such as projection light incident on the counter substrate 20 is schematically shown by a one-dot chain line arrow.

  In the comparative example, the counter substrate 20 is configured as a microlens substrate. More specifically, the counter substrate 20 is formed with recesses for defining the lens curved surface of the microlens 500 in the transparent member 515 corresponding to the pixel electrodes 9a. Thus, a transparent adhesive layer 530 having a refractive index higher than that of the transparent member 515 is formed, and the cover glass 510 is adhered to the transparent member 515 by the adhesive layer 530. In addition, in FIG. 8, a black matrix 23 or the like that defines a non-opening region is formed below the cover glass 510 on the counter substrate 20 side.

  The light incident on the counter substrate 20 is collected by each microlens 500. At this time, among the light incident on the counter substrate 20, in each pixel portion, in addition to the light traveling toward the opening region, the light traveling toward the non-opening region is also collected by the microlens 500. Then, the light collected by each microlens 500 is transmitted through the liquid crystal layer 50 and irradiated onto the pixel electrode 9a. Therefore, in each pixel portion, the light condensed by the microlens 500 is concentrated and irradiated at one place. For example, the liquid crystal layer 50, the alignment film 16, and the conductive film constituting the pixel electrode 9a are heated. May deteriorate.

  In addition, due to refraction at the lens curved surface of the microlens 500, the light traveling direction is changed outside the viewing angle, or changed to a direction different from the direction toward the projection lens of the projector as will be described later. The light contributing to the light is reduced, the light loss is increased, and problems such as a decrease in contrast ratio occur.

  And in the comparative example, when these various problems are to be corrected, the degree of other problems becomes large, or the problems must be left unattended, and are in a contradictory relationship with each other. It is difficult to eliminate.

  On the other hand, in the present embodiment, each microlens 500 can make parallel light incident on each pixel while condensing light such as projection light incident on the electro-optical device. In particular, in the present embodiment, the shape of each microlens 500 of the microlens substrate 20 such as the lens thickness and the curvature radius of each of the first and second lens curved surfaces 500a and 500b is adjusted according to the pixel aperture ratio. By doing so, it is possible to obtain a uniform light distribution in each pixel and within the pixel.

  Therefore, in the present embodiment, it is possible to prevent a decrease in the amount of light that actually contributes to display and to effectively use the light collected by the microlens 500. In addition, in each pixel, local irradiation of light collected by the microlens 500 can be prevented. Therefore, it is possible to further improve the light use efficiency, prevent a decrease in contrast ratio, and prevent the liquid crystal layer 50 and the like from being significantly damaged and deteriorated by light irradiation. Therefore, in the present embodiment, high-quality image display can be performed in the liquid crystal device.

  In the present embodiment described above, instead of providing the data line driving circuit 101 and the scanning line driving circuit 104 on the TFT array substrate 10 in the electro-optical device, for example, for driving mounted on a TAB (Tape Automated Bonding) substrate. The LSI may be electrically and mechanically connected to the external circuit connection terminal 102 via an anisotropic conductive film. Further, for example, a TN (Twisted Nematic) mode, a VA (Vertically Aligned) mode, and a PDLC (Polymer Dispersed Liquid) are respectively provided on the side on which the projection light of the microlens substrate 20 is incident and the side on which the emission light of the TFT array substrate 10 is emitted. A polarizing film, a retardation film, a polarizing plate, and the like are arranged in a predetermined direction according to an operation mode such as a (Crystal) mode and a normally white mode / normally black mode.

  In the electro-optical device described above, the microlens substrate 20 as shown in FIGS. 1 and 2 is used as the counter substrate. However, such a microlens substrate 20 can also be used as the TFT array substrate 10. It is. Alternatively, it is possible to attach the microlens substrate 20 to the TFT array substrate 10 side by simply using a glass substrate or the like formed with a counter electrode or an alignment film as the counter substrate (not the microlens substrate 20). . That is, the microlens of the present invention can be built or attached to the TFT array substrate 10 side.

<3: Microlens substrate manufacturing method>
Next, a method for manufacturing the microlens substrate 20 according to the present embodiment will be described with reference to FIGS. FIG. 9 and FIG. 10 are process diagrams schematically showing the configuration of the microlens substrate in each step of the manufacturing process in order with respect to the cross-sectional view of FIG.

  First, as shown in FIG. 9A, an amorphous silicon film is formed on a transparent substrate 210 as a mask 902 by, for example, CVD (Chemical Vapor Deposition). The mask 902 may be a hydrofluoric acid resistant Cr film, a polysilicon film, or the like. Then, in the mask 902, a plurality of openings 902a are formed at positions corresponding to the positions where the concave portions 212 of the transparent substrate 210 are formed, for example, by patterning using a photolithography method for the mask 902.

  Thereafter, as shown in FIG. 9B, a plurality of recesses 212 are formed by performing, for example, wet etching on the transparent substrate 210 through a mask 902. Thereafter, as shown in FIG. 9C, the mask 902 is removed.

  In addition, formation of the recessed part 212 in the transparent substrate 210 is not restricted to the procedure demonstrated with reference to FIG. 9, You may form each recessed part 212 by using a multiple types of mask.

  Thereafter, as shown in FIG. 10A, the first transparent material film 230 is formed by being joined to each recess 212. More specifically, the first transparent material film 230 is, for example, a sheet-like or film-like transparent resin film disposed so as to cover each concave portion 212 and, for example, pressurized and bonded to each concave portion 212 to be transparent. It is formed by bonding to the substrate 210. Alternatively, for example, the first transparent material film 230 may be formed by a spin coating method, a PVD method, or the like. Thus, in the first transparent material film 230, the first lens curved surface 500a is formed on the joint surface with the concave portion 212 corresponding to each concave portion 212, and the surface opposite to the first lens curved surface 500a. In addition, the shape of the first lens curved surface 500a is transferred to form the second lens curved surface 500b. The film thickness d1 of the first transparent material film 230 is, for example, about 10 to 40 μm.

  Therefore, in the present embodiment, by adjusting the shape of each recess 212, the shape of the first lens curved surface 500a of the microlens 500 can be adjusted, and further, the shape of the second lens curved surface 500b can also be adjusted. .

  At this time, mechanical characteristics such as Young's modulus and physical characteristics such as viscosity of the first transparent material forming the first transparent material film 230 are selectively adjusted, and in addition to these, application conditions and film formation conditions are adjusted. The manufacturing conditions such as the above may be adjusted, and the film thickness may be further adjusted. Accordingly, the radius of curvature of each second lens curved surface 500b shown in FIG. 2B is made smaller than that of the first lens curved surface 500a, or on the contrary, and adjusted independently. be able to.

  For example, if the first transparent material film 230 is formed of a relatively hard first transparent material, that is, a material having a relatively large Young's modulus, each of the second lens curved surfaces 500b is formed in the first transparent material film 230. The curvature radius R2 can be further increased. On the other hand, if the first transparent material film 230 is formed of a relatively soft first transparent material, that is, a material having a relatively low Young's modulus, The radius of curvature R2 of the second lens curved surface 500b can be formed to be smaller. Furthermore, if the film thickness d1 of the first transparent material film 230 is reduced, the radius of curvature R2 of the second lens curved surface 500b can be increased. If the film thickness d1 is increased, the radius of curvature R2 of the second lens curved surface 500b can be adjusted to be smaller.

  Thereafter, as shown in FIG. 10 (b), the first transparent material film 230 is formed on the upper layer side by, for example, a PVD method or a CVD method, or a sheet-like or film-like transparent material film is first formed. Similarly to the transparent material film 230, the second transparent material film 200 is formed by bonding to the first transparent material film 230. In this state, in the second transparent material film 200, the concave and convex shape due to the presence of each concave portion 212 is formed on the surface opposite to the joint surface with the first transparent material film 230, so that the concave portion 212 in the transparent substrate 210 is formed. Compared with the formed surface, the surface can be more relaxed.

  Therefore, it is possible to obtain relatively good flatness on the surface of the second transparent material film 200, but further flattening processing such as CMP processing is performed as shown in FIG. Alternatively, it may be applied to the second transparent material film 200. In addition to the CMP process, as the planarization process, for example, various means such as coating the surface of the second transparent material film 200 can be used.

  Therefore, according to the present embodiment as described above, each microlens 500 can be formed as a meniscus lens by a simpler manufacturing process.

<4: Modification>
Next, a modification will be described with reference to FIG. FIG. 11 is a cross-sectional view showing the configuration of the microlens substrate in the present modification with respect to a cross-sectional portion corresponding to FIG.

  As shown in FIG. 11, convex portions 213 may be formed on the transparent substrate 210 instead of the concave portions 212. In this case, the first transparent material film 230 having a lower refractive index than that of the transparent substrate 210 is formed by being joined to each convex portion 213, and the second transparent material film 200 is more than the first transparent material film 230. Is also formed to have a high refractive index.

  Therefore, according to this modification, in the first transparent material film 230, the first lens curved surface 500a of each microlens 500 is formed as a convex lens curved surface, and the second lens curved surface 500b is also convex. It can be formed as a lens curved surface.

  Even in such a configuration, the same operations and effects as those of the above-described embodiment can be obtained. That is, each microlens 500 can be formed as a meniscus lens by a simpler manufacturing process.

<5; Electronic equipment>
Next, an overall configuration, particularly an optical configuration, of an embodiment of a projection color display device as an example of an electronic apparatus using the above-described electro-optical device as a light valve will be described. FIG. 12 is a schematic cross-sectional view of the projection type color display device.

  In FIG. 12, a liquid crystal projector 1100, which is an example of a projection type color display device, prepares three liquid crystal modules including a liquid crystal device having a drive circuit mounted on a TFT array substrate, and RGB light valves 100R, 100G, and The projector is configured as 100B. In the liquid crystal projector 1100, when projection light is emitted from a lamp unit 1102 of a white light source such as a metal halide lamp, light components R, G, and R corresponding to the three primary colors of RGB are obtained by three mirrors 1106 and two dichroic mirrors 1108. The light is divided into B and led to the light valves 100R, 100G and 100B corresponding to the respective colors. In particular, the B light is guided through a relay lens system 1121 including an incident lens 1122, a relay lens 1123, and an exit lens 1124 in order to prevent light loss due to a long optical path. Light components corresponding to the three primary colors modulated by the light valves 100R, 100G, and 100B are synthesized again by the dichroic prism 1112 and then projected as a color image on the screen via the projection lens 1114.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed within a scope not departing from the gist or concept of the invention that can be read from the claims and the entire specification, and a microlens substrate accompanying such changes Further, the manufacturing method thereof, the electro-optical device including the microlens substrate, and the electronic apparatus including the electro-optical device are also included in the technical scope of the present invention.

FIG. 1A is a schematic perspective view of a microlens substrate, and FIG. 1B is a schematic perspective view showing a configuration including a cross-sectional portion taken along the line A-A ′ of FIG. FIG. 2A is a partially enlarged plan view showing a portion related to four microlenses in the microlens substrate, and FIG. 2B is an enlarged cross-sectional view showing the configuration of the microlens. It is a top view which shows the whole structure of an electro-optical apparatus. It is H-H 'sectional drawing of FIG. It is a figure which shows equivalent circuits, such as various elements and wiring in the some pixel formed in the matrix form which comprises the image display area | region of an electro-optical apparatus. It is a top view which shows typically the arrangement | positioning relationship of the light shielding film and opening area | region in a microlens board | substrate. It is a figure which shows the structure of the cross section shown in FIG. 4 about a some pixel in detail. It is sectional drawing which shows the structure of the cross-sectional part corresponding to FIG. 7 about a comparative example. FIG. 3 is a process diagram (part 1) schematically showing the configuration of the microlens substrate in each step of the manufacturing process in order with respect to the cross-sectional view of FIG. FIG. 3 is a process diagram (part 2) schematically showing the configuration of the microlens substrate in each step of the manufacturing process in order with respect to the cross-sectional view of FIG. It is sectional drawing which shows the structure of the microlens board | substrate in this modification about the cross-sectional part corresponding to FIG.2 (b). 1 is a schematic cross-sectional view showing a color liquid crystal projector as an example of a projection type color display device which is an embodiment of an electronic apparatus of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 200 ... 2nd transparent material film | membrane, 210 ... Transparent substrate, 212 ... Recessed part, 230 ... 1st transparent material film | membrane, 500 ... Micro lens, 500a ... 1st lens curved surface, 500b ... 2nd lens curved surface

Claims (10)

A plurality of lens forming portions each defining the first lens curved surface of the microlens, a transparent member arranged in a predetermined pattern;
The first lens curved surface is joined to each of the plurality of lens forming portions, and the first lens curved surface is formed on a joint surface with each of the plurality of lens forming portions. A first transparent material film having a second lens curved surface of the microlens to which the shape of the lens curved surface is transferred and having a refractive index different from that of the transparent member;
A microlens substrate comprising: a second transparent material film which is bonded to the second lens curved surface and has a refractive index different from that of the first transparent material film.   2. The microlens substrate according to claim 1, wherein in the first transparent material film, the second lens curved surface is formed with a curvature radius different from that of the first lens curved surface.   The microlens substrate according to claim 1 or 2, wherein each of the plurality of lens forming portions is formed as a concave portion. The first transparent material film is formed of a first transparent material having a refractive index larger than that of the transparent member, and the second transparent material film has a smaller refraction than that of the first transparent material film. The microlens substrate according to claim 3, wherein the microlens substrate is formed of a second transparent material having a specific rate.   The microlens substrate according to claim 1, wherein each of the plurality of lens forming portions is formed as a convex portion. The first transparent material film is formed of a first transparent material having a refractive index smaller than that of the transparent member, and the second transparent material film is larger in refraction than the first transparent material film. The microlens substrate according to claim 5, wherein the microlens substrate is formed of a second transparent material having a high rate. The said 2nd transparent material film | membrane has a surface by which the planarization process was performed in the opposite side to the side joined with the said 2nd lens curved surface. The microlens substrate according to 1. The microlens substrate according to any one of claims 1 to 7,
A display electrode facing the microlens;
An electro-optical device comprising: a wiring or an electronic element electrically connected to the display electrode.   An electronic apparatus comprising the electro-optical device according to claim 8. A first step of forming, on the transparent member, a plurality of lens forming portions each defining a first lens curved surface of the microlens in a predetermined pattern;
Forming each of the plurality of lens forming portions of the first transparent material film by forming a first transparent material film having a refractive index different from that of the transparent member. Forming the first lens curved surface on the cemented surface, and transferring the shape of the first lens curved surface to the surface opposite to the first lens curved surface, thereby forming the second lens curved surface of the microlens. A second step of forming;
And a third step of forming a second transparent material film having a refractive index different from that of the first transparent material film and bonded to the second lens curved surface.

Images