JP2007171858A - Method for manufacturing microlens, microlens substrate, method for manufacturing electrooptical device, electrooptial device, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably manufacture the lens curved face of an aspheric microlens in a prescribed shape. <P>SOLUTION: A method for manufacturing the microlens includes a process for boring each initial hole 212a by applying patterning to a substrate 210 through a resist 900 and a mask 800, a process for expanding a bore of each second opening part 802 by applying isotropic etching to the mask 800 through the resist 900, a process for boring a bored hole 212b by removing the resist 900 after the process and applying anisotropic etching to the substrate 210 through the mask 800, and a process for forming a recess 212 by applying isotropic etching to the substrate 210 to bore a bored hole 212b after the process. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes, for example, a microlens substrate used in an electro-optical device such as a liquid crystal device, a manufacturing method of the microlens, an electro-optical device including the microlens substrate, a manufacturing method thereof, and the electro-optical device. The present invention relates to the technical field of electronic devices such as projectors.

  For example, a liquid crystal device constituting a light valve of a projector as an electro-optical device is provided with a microlens substrate on which a microlens corresponding to each pixel is formed as a counter substrate. In a liquid crystal device, such a counter substrate is disposed so that each microlens is opposed to a pixel electrode with respect to a TFT array substrate on which a pixel electrode or the like is formed, and between the counter substrate and the TFT array substrate. For example, liquid crystal is sandwiched as an electro-optical material.

  Here, according to the microlens manufacturing method disclosed in Patent Document 1 or 2, each microlens is formed as an aspherical lens. According to Patent Document 1, a plurality of concave portions each having a lens curved surface of a microlens are formed on a transparent substrate by performing wet etching using, for example, two types of masks each having a plurality of openings. Open a hole. The two types of masks have different opening diameters, and the first wet etching process is performed on the transparent substrate using one of the masks having a relatively small opening. Open an initial hole in each recess. Then, after removing one of the masks, the other mask having an opening having a diameter larger than the opening of the one mask is formed on the transparent substrate, and through the other mask, A wet etching process is performed on the transparent substrate to further dig the initial hole, thereby forming a plurality of concave portions each having a lens curved surface of an aspherical microlens.

  Further, according to Patent Document 2, on the contrary, first, the other mask having an opening having a relatively large diameter is formed on the transparent substrate, and then this mask is further formed on the other mask. After forming one mask with an opening having a diameter smaller than the opening of the other mask, performing a wet etching process on the transparent substrate through the one mask, and opening the initial hole Further, by continuously performing the wet etching process through the other mask, the initial hole is dug to form a plurality of recesses.

JP 2003-279949 A JP 2004-69790 A

  However, according to the microlens manufacturing method as described above, the positional deviation between the opening in the other mask and the initial hole already opened in the transparent substrate occurs, or the opening in the one mask However, there is a problem that a positional deviation from the opening in the other mask occurs.

  As a result, the lens curved surface of the microlens in each concave portion cannot be stably produced in a predetermined shape, and it becomes difficult to accurately control the characteristics such as the focal position of the microlens, and the characteristics of each microlens. Inconvenience occurs in that there is variation. In addition, the number of masks necessary for manufacturing an aspheric lens requires two or more masks, and there is a technical problem that shortens the manufacturing process.

  The present invention has been made in view of the above-described problems, and a manufacturing method of a microlens capable of making a lens curved surface of an aspherical microlens into a good shape relatively easily, by the manufacturing method. It is an object of the present invention to provide a microlens substrate to be manufactured, an electro-optical device including the microlens substrate, a manufacturing method thereof, and an electronic apparatus including the electro-optical device.

  In order to solve the above-described problem, the microlens manufacturing method of the present invention includes a first step of forming a mask on a substrate, a second step of forming a resist on the mask, and patterning the resist. A third step of arranging a plurality of first openings in a predetermined pattern and opening the holes, and performing a first etching process on the mask through the plurality of first openings, thereby providing a plurality of second A fourth step of opening an opening, and a second etching process is performed on the substrate through the plurality of first openings and the plurality of second openings to open a plurality of initial holes. A fifth step of forming a hole, and after the fifth step, an isotropic etching process is performed on the mask through the plurality of first openings, thereby each of the plurality of second openings. A sixth step of widening the aperture, and after the sixth step, the label A seventh step of removing the strike, and after the seventh step, the substrate is subjected to an anisotropic etching process through the plurality of second openings to dig the initial hole, An eighth step of opening a plurality of dug holes each formed of a first hole opened corresponding to the second opening and a second hole opened at a bottom of the first hole; And after the eighth step, through the plurality of second openings, the substrate is subjected to an isotropic etching process to dig the plurality of digging holes, and the cross-sectional shape is straight. A ninth step of forming a plurality of concave portions formed of a plurality of curves, a tenth step of removing the mask after the ninth step, and a transparent material filling the concave portions after the tenth step. And an eleventh step of forming a microlens.

  According to the method for manufacturing a microlens of the present invention, a transparent substrate such as a quartz substrate or a glass substrate is used as the substrate. In the first step, a mask for patterning such a substrate is formed. In two steps, a resist for patterning the mask is formed. Note that the “resist” here is not limited to any material as long as it can be patterned by, for example, photolithography or the like, and in a broad sense, “mask” or “second mask”, “patternable film or It can be rephrased as “layer”.

  Subsequently, in the third step, for example, a plurality of first openings are formed in the resist by patterning using a photoetching process. For example, a resist is formed in the second step, and in the third step, the resist is exposed and then developed and patterned to open a plurality of first openings.

  Thereafter, in the fourth step, a first etching process, typically anisotropic etching such as dry etching, is performed on the mask through the resist, that is, through the plurality of first openings. Thus, a plurality of second openings corresponding to the plurality of first openings are opened.

  Subsequently, in the fifth step, anisotropic etching such as dry etching is typically performed on the substrate through the resist and the mask, that is, through the plurality of first openings and the plurality of second openings. A plurality of initial holes are formed by performing the second etching process. In the second etching process, for example, by adjusting etching conditions such as etching time, the shape of the initial hole, more specifically, for example, the depth of the initial hole along the direction perpendicular to the substrate surface, In addition, the diameter of the initial hole in the direction along the substrate surface can be adjusted.

  Thereafter, in the sixth step, an isotropic etching process such as wet etching is performed on the mask through the resist, that is, through the plurality of first openings. Thereby, an isotropic etching process is performed on the side wall defining the opening of the second opening through each first opening, and the diameter of the second opening in the direction along the substrate surface is changed to the sixth. It can be larger than the value before the process.

  As described above, in the sixth step, the shape of each first opening is changed almost without using a resist common to the opening of each second opening and without patterning the resist again. Instead, the diameter of each second opening is increased by re-patterning the mask. Therefore, for each second opening, it is possible to prevent the second opening from being displaced when the diameter of the second opening is increased with respect to the position before the sixth step. Thereby, after expanding the diameter of each 2nd opening part in a 6th process, it can prevent that the position with respect to a corresponding initial hole shifts | deviates. Here, in a 6th process, the diameter of each 2nd opening part can be adjusted by adjusting etching conditions, such as etching time.

  Then, after the sixth step, the seventh step is performed to remove the resist, and then the eighth step is performed. In the eighth step, each initial hole is dug to open the dug hole by performing anisotropic etching treatment on the substrate through the mask, that is, through the plurality of second openings. . Each digging hole has a first hole that is opened by transferring the shape of the second opening to the substrate, and a shape of the initial hole that is transferred to the substrate. It is formed by the opened second hole. For example, each digging hole is opened corresponding to the initial hole from the bottom of the first hole and the first hole continuously opened from the second opening corresponding to the second opening. And a second hole.

  In the sixth step described above, by preventing the displacement of the second opening with respect to the initial hole, it is possible to prevent the displacement of the first hole and the second hole in the dug hole. In the sixth step, the diameter of the corresponding first hole can be adjusted by adjusting the diameter of the second opening. In addition, in the fifth step described above, by adjusting the shape of the initial hole, it is possible to adjust the shape of the second hole correspondingly continuously opened in the first hole.

  Furthermore, in the eighth step, the depth of the digging hole along the direction perpendicular to the substrate surface can be adjusted by adjusting the etching conditions such as the etching time. By adjusting the depth of the digging hole in this way, the depth of the recess along the direction perpendicular to the substrate surface, that is, the thickness of the microlens can be adjusted. At this time, by adjusting the depth of the digging hole, the depth of the first hole in the digging hole is also adjusted, so that the shape of the vertical straight portion that stands up toward the edge of the recess as described later is also obtained. Can be adjusted.

  After the eighth step, the ninth step is performed to dig each digging hole by performing an isotropic etching process on the substrate through the mask, that is, through the plurality of second openings. To form a recess. Each of the recesses has a cross-sectional shape including a straight line and a plurality of curves. Here, the “cross-sectional shape” means a shape in a cross section including the center line of the microlens. At this time, in each digging hole, the tip of the lens curved surface of the microlens is formed by the isotropic etching process so that the substrate is dug from the bottom of the second hole, and the first hole is formed. When the substrate is dug from the bottom of the substrate, a part of the lens curved surface of the microlens that is continuous with the tip is formed. Further, an isotropic etching process is performed on the side wall of the first hole to dig up the substrate.

  Therefore, the lens curved surface of the microlens in each concave portion has a flat portion that is flat along the plane intersecting the centerline at the tip portion through which the centerline of the microlens passes, and the shape in the cross section including the centerline is Two or more arc-shaped curves having the same radius of curvature and different centers at different positions on the center line are continuously connected from the flat portion, and are rotationally symmetric about the center line. In addition, at least some of the plurality of recesses each have a shape in the cross-section that is continuous from the arc-shaped curve toward the edge located on the side opposite to the center line and linear with respect to the surface of the substrate. It is formed including an upright straight portion.

  Therefore, in the microlens manufacturing method of the present invention, each microlens can be formed as a rotationally symmetric two-stage lens and can be formed as an aspheric lens.

  Here, the etching conditions such as the etching time in the ninth step are adjusted, and in addition, in the eighth step, the shape of each digging hole is adjusted as described above to adjust the shape of the microlens. be able to. That is, in accordance with the thickness of the microlens and the shape of the second hole, the shape of the tip portion through which the center line of the microlens passes is adjusted in the lens curved surface of the microlens in the concave portion, and the first hole Corresponding to the shape, the shape of the portion continuing to the tip can be adjusted.

  Then, after the ninth step, the tenth step is performed to remove the mask, and then the eleventh step is performed to fill each recess formed in the substrate with a transparent material. A microlens is formed by a transparent material filled in each recess.

  Therefore, according to the microlens manufacturing method of the present invention as described above, the number of masks required for forming the lens curved surface of the microlens in each recess is reduced as compared with the prior art as already described. Is possible. Therefore, various processes required for forming and patterning such a mask can be reduced. As a result, the manufacturing process of the microlens can be shortened.

  Furthermore, the lens curved surface of each microlens can be stably formed in a predetermined shape, and the characteristics such as the focal position of each microlens can be controlled with high precision, and a plurality of microlenses with uniform characteristics can be manufactured. can do.

  In one aspect of the microlens manufacturing method of the present invention, in the fourth step, as the first etching process, anisotropic etching having directivity in a direction intersecting the substrate is performed, and in the fifth step, As the second etching process, anisotropic etching having directivity in the direction crossing the substrate is performed.

  According to this aspect, for example, by performing anisotropic etching having directivity in the direction intersecting the substrate, such as the normal direction of the substrate, the second opening extending in the direction perpendicular to the substrate can be opened. An initial hole extending in this direction can be opened. At this time, the diameter of the first opening and the diameter of the second opening can be made uniform, and further, the diameter of the initial hole can be made uniform.

  In another aspect of the method for manufacturing a microlens of the present invention, the method further includes a twelfth step of forming a control film for controlling the shape of the concave portion on the substrate before the first step. In step 5, the second etching process is performed on the control film in addition to the substrate, and in the eighth process, the anisotropic etching process is performed on the control film in addition to the substrate. In the ninth step, the isotropic etching process is performed on the control film in addition to the substrate.

  According to this aspect, the control film is formed of a material that has an etching rate different from that of the substrate, particularly in the etching process in the ninth step. Thus, in the ninth step, the etching rate of the substrate that defines the opening and the etching rate of the control film that defines the edge of the opening in the opening of each recess to be formed in the substrate are different. Therefore, it is possible to further adjust the shape of the lens curved surface of the microlens at the edge of each recess, and the degree of freedom in designing the microlens can be increased.

  In the aspect further including the twelfth step of forming the control film, in the twelfth step, the control film has an etching rate larger than that of the substrate in the isotropic etching process in the ninth step. You may manufacture so that it may form with material.

  If manufactured in this way, in the ninth step, the etching rate of the control film that defines the edge of the opening, relative to the etching rate of the substrate that defines the opening, in the opening of each recess to be formed in the substrate. Can be increased. As a result, in each cross-section including the center line of the microlens, the shape of the edge of the recess is inclined from the bottom of the recess to the edge along the lens curved surface of the microlens to form a recess without a control film. It can be formed so as to have a gentle shape as compared with the case of the above.

  In order to solve the above problems, a method for manufacturing an electro-optical device according to the present invention includes a step of forming a microlens by the above-described microlens manufacturing method of the present invention (including various aspects thereof), and the microlens. And a step of forming a display electrode oppositely and a step of forming at least one of a wiring and an electronic element by being electrically connected to the display electrode.

  According to the manufacturing method of the electro-optical device of the present invention, since the micro lens is manufactured by the above-described manufacturing method of the micro lens of the present invention, the electro-optical device has excellent light collecting ability and uniform characteristics. Light can be condensed by each microlens and incident on each pixel. Accordingly, it is possible to manufacture an electro-optical device that is excellent in light use efficiency and can make the contrast ratio uniform in each pixel.

  In order to solve the above-described problem, the microlens substrate of the present invention has a flat portion that is flat along a plane intersecting the centerline at a tip portion through which the centerline of the microlens passes, and a cross section including the centerline. 2 or more curves, each having a radius of curvature equal to each other and centers at different positions on the center line, are continuously connected from the flat portion, and are rotationally symmetric about the center line. A substrate having a plurality of concave portions each having a lens curved surface of the microlens and a transparent member that fills the plurality of concave portions and forms the microlens, wherein at least a part of the plurality of concave portions is provided. , A shape in the cross section is continuous from the arcuate curve toward the edge located on the opposite side of the center line, and a straight portion intersecting the surface of the substrate Nde is formed.

  According to the microlens substrate of the present invention, it is possible to improve the light utilization efficiency by each microlens having excellent light collecting ability and uniform characteristics.

  In order to solve the above-described problems, an electro-optical device of the present invention includes the above-described microlens substrate of the present invention, a display electrode facing the microlens, wirings and electrons electrically connected to the display electrode. At least one of the elements.

  According to the electro-optical device of the present invention, it is possible to improve the light utilization efficiency and make the contrast ratio uniform in each pixel, and to perform high-quality image display.

  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.

  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; First Embodiment>
First, a first embodiment according to the present invention will be described with reference to FIGS.

<1-1: 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 relating to four microlenses in the microlens substrate, and FIG. 2B shows a configuration of an arbitrary microlens. 3A is a partially enlarged plan view, FIG. 3A is an enlarged cross-sectional view showing the configuration of the FF ′ cross-sectional portion of FIG. 2B, and FIG. 3B is a cross-sectional view of FIG. -J 'It is an expanded sectional view which shows the structure of a cross-section part.

  As shown in FIG. 1A, a microlens substrate 20 of this embodiment includes a transparent substrate 210 made of, for example, a quartz plate, and a cover glass 200 bonded to the transparent substrate 210 with an adhesive layer 230 as will be described later. And.

  In the microlens substrate 20, a large number of microlenses 500 arranged in a matrix form are formed in the lens formation region 20 a. More specifically, in FIG. 1B, in the transparent substrate 210, a large number of concave depressions, that is, concave portions 212 are formed in the lens forming region 20a in an array. In each recess 212, a transparent adhesive layer having a higher refractive index than that of the transparent substrate 210 is formed by curing an adhesive made of, for example, a transparent photosensitive resin material, which bonds the cover glass 200 and the transparent substrate 210 to each other. 230 is filled.

  The curved surface of each microlens 500 is generally defined by the transparent substrate 210 and the adhesive layer 230 having different refractive indexes. That is, each recess 212 defines a lens curved surface of the microlens 500. Since the adhesive layer 230 is made of a transparent material having a refractive index higher than that of the transparent substrate 210, such as an epoxy resin, the refractive index of the adhesive layer 230 is larger than that of the concave portion 212. The microlens 500 is formed by a part of the adhesive layer 230 filled in the recess 212.

  In FIG. 2A, in the present embodiment, each concave portion 212 has, for example, the lens curved surface of the microlens 500 defined by it adjacent to the horizontal direction (X direction) or the vertical direction (Y direction). The concave portion 212 is formed so as to intersect with the lens curved surface defined by the concave portion 212, and the four lens curved surfaces are formed in contact with each other at the corner portion 501 at the edge of each concave portion 212.

  Further, in FIG. 2B, each recess 212 is opened by applying an isotropic etching process to the transparent substrate 210 by a manufacturing method as will be described later. The diameter R0 of each microlens is defined by the length of the diagonal line passing through O10 and connecting the two corners at the edge of the recess 212.

  In addition, according to the present embodiment, since the microlens substrate 20 is manufactured by the microlens manufacturing method according to the present invention as described later, the lens curved surface of each microlens 500 has the following shape. Have. In FIG. 3A and FIG. 3B, the center line of the microlens 500 is indicated by a one-dot chain line.

  3A and 3B, the lens curved surface of the microlens 500 in the recess 212 is rotationally symmetric with respect to the centerline of the microlens 500 or with reference to the centerline, and the tip portion through which this centerline passes. 2 has a flat portion that is flat along the substrate surface, and a shape on one side with respect to the center line is defined by two kinds of curvature circles C1 and C2 each having a radius of curvature of approximately equal to r1. Including a curved portion of the seed, these two curved portions are formed by continuously joining the flat portion. 3A and 3B also show the centers of curvature O1 and O2 of the two types of curvature circles C1 and C2.

  That is, the microlens 500 has a shape including a plurality of curved surfaces with different positions of the center of curvature radius.

  Further, in FIG. 3A, if attention is paid to the configuration of the cross-sectional portion including the diagonal line at the edge of the concave portion 212 (that is, the FF ′ cross-sectional portion in FIG. One end side is continuously coupled to one of the two types of curved portions coupled to the portion, and the one end side is raised from the one end side toward the edge of the recess 212 on the other end side, in a direction intersecting the surface of the substrate. It is formed including an extending straight line portion L0.

  That is, the upper end portion of the microlens 500 is formed in a cylindrical shape.

  Therefore, in the present embodiment, each microlens 500 is formed as a rotationally symmetric two-stage lens and an aspherical lens.

<1-2: 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. 4 and 5. FIG. 4 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.

  4 and 5, 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. In addition, although not shown in FIG. 4 or FIG. 5, the sealing material 52 includes glass fiber or glass beads for setting the distance (inter-substrate gap) between the TFT array substrate 10 and the microlens substrate 20 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. 4 or FIG. 5, 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. 5, on the TFT array substrate 10, a pixel switching TFT (Thin Film Transistor; hereinafter referred to as “TFT” as appropriate), a scanning line, a data line, and the like 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. 6 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. 6, 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.

  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 electro-optical device described above will be described with reference to FIGS. FIG. 7 is a plan view schematically showing the arrangement relationship between the light shielding film 23 and the opening region 700 in the microlens substrate 20, and FIG. 8 shows the configuration of the cross section shown in FIG. 5 in more detail for a plurality of pixels. FIG. 6 is a cross-sectional view for explaining the function of each microlens 500.

  In FIG. 8, in the microlens substrate 20, a light shielding film 23 having a grid-like plane pattern as shown in FIG. 7 is formed on the cover glass 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. 8, 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. 8, a counter electrode 21 made of a transparent conductive film is formed on the cover glass 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. 8, the counter electrode 21. (Lower side).

  On the other hand, in FIG. 8, 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. 8, light such as projection light incident on the microlens substrate 20 is collected by each microlens 500. In FIG. 8, the appearance of light collected by the microlens 500 is schematically shown by an alternate long and short dash line. Then, the light collected by each microlens 500 is transmitted through the liquid crystal layer 50 and irradiated onto the pixel electrode 9a, passes through the pixel electrode 9a, and is emitted from the TFT array substrate 10 as display light. Therefore, light that is directed to the non-opening region among the light that is incident on the microlens substrate 20 can also be incident on the opening region 700 due to the condensing action of the microlens 500, and thus the effective aperture ratio in each pixel can be increased. it can. That is, it is possible to display a brighter image by increasing the light utilization efficiency.

  In particular, in the present embodiment, since the microlens substrate 20 is manufactured by the microlens manufacturing method according to the present invention as described later, each microlens 500 having excellent light collecting ability and uniform characteristics allows light to be emitted. In addition to improving the utilization efficiency, it is possible to make the contrast ratio uniform in each pixel, and it is possible to perform high-quality image display.

  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 to 3 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.

<1-3; Manufacturing method of microlens>
Next, a method for manufacturing a microlens according to the present embodiment will be described with reference to FIGS. The microlens substrate 20 as described above is manufactured by the microlens manufacturing method described below, and an electro-optical device is manufactured as described later.

  9 to 11 and FIG. 13 are process diagrams sequentially illustrating the configuration of the cross-sectional portion of the microlens substrate 20 in each process of the manufacturing process. 12A is a cross-sectional view corresponding to the portion shown in FIG. 3A, and FIG. 12B is a cross-sectional view corresponding to the portion shown in FIG. 3B. It is sectional drawing for demonstrating the process which concerns. Note that all the configurations shown in FIG. 9 to FIG. 13 show the cross-sectional portion including the center line of the microlens 500.

  First, in the process of FIG. 9A, amorphous silicon, polysilicon, or the like is formed on the transparent substrate 210 as a mask 800 by, for example, a CVD (Chemical Vapor Deposition) method. The mask 800 is formed as a mask for patterning the transparent substrate 210 as will be described later.

  Thereafter, in the process of FIG. 9B, a resist 900 is formed on the mask 800 by, for example, a spin coating method. The resist 900 is formed for patterning the mask 800. By forming the resist 900 from a resist for photolithography, it is possible to simplify and shorten the processes related to the formation and patterning of the resist 900.

  Thereafter, in the step of FIG. 9C, patterning is performed on the resist 900 by, for example, photolithography to open a plurality of first openings 902 in the lens formation region 20a. In the step of FIG. 9B, a resist 900 is formed of a material different from the resist, a resist is formed for patterning the resist 900, and a photo-etching process is performed on the resist 900 through the resist. , The plurality of first openings 902 may be opened, and the resist may be removed. In this case, the resist 900 can also be called “another mask” or “second mask” superimposed on the mask 800.

  Thereafter, in the process of FIG. 10A, for example, an anisotropic dry etching process is performed as a first etching process on the mask 800 through the plurality of first openings 902 in the resist 900 to form a lens. A plurality of second openings 802 are opened in the region 20a. At this time, the shape of each first opening 902 is transferred to the mask 800 and the second opening 802 is opened.

  Note that the first etching process in the step of FIG. 10A may be performed by an isotropic dry etching process or a wet etching process. In this case, the first etching process has a shape different from that in the present embodiment. Two openings are obtained.

  Thereafter, in the process of FIG. 10B, the second etching process is performed on the transparent substrate 210 through the plurality of second openings 802 in the mask 800 and the plurality of first openings 902 in the resist 900. For example, anisotropic dry etching is performed to open the initial holes 212a of the plurality of recesses 212 in the lens forming region 20a. At this time, the shape of each second opening 802 is transferred to the transparent substrate 210, whereby the initial hole 212a is opened.

  Note that the second etching process in the step of FIG. 10B may be performed by an isotropic dry etching process or a wet etching process. In this case, the second etching process has a shape different from that of the present embodiment. An initial hole is obtained.

  Here, in the second etching process, for example, by adjusting the etching conditions such as the etching time, the shape of the initial hole 212a, more specifically, for example, along the direction perpendicular to the substrate surface of the transparent substrate 210 is used. In addition, the depth of the initial hole 212a, and in addition to this, the diameter of the initial hole 212a in the direction along the substrate surface of the transparent substrate 210 can be adjusted. Furthermore, as described above, when the second etching process is performed by an anisotropic etching process, when the plurality of second openings 802 of the mask 800 are opened, the etching time of the first etching process, etc. By adjusting the etching conditions and adjusting the diameter of each second opening 802 in the direction along the substrate surface of the transparent substrate 210, the shape of the initial hole 212a can be adjusted.

  In addition, as described above, when both the first etching process in the process of FIG. 10A and the second etching process in the process of FIG. When opening each first opening 902 in 900, the shape of the initial hole 212a can be adjusted through the second opening 802 of the mask 800 by adjusting the shape of the first opening 902. It becomes possible.

  Thereafter, in the process of FIG. 10C, the mask 800 is again subjected to an isotropic etching process through the resist 900. At this time, the isotropic etching process may be performed by a dry etching process or a wet etching process. Thereby, an isotropic etching process is performed on the side wall defining the opening of the second opening 802 via each first opening 902, and the second opening in the direction along the substrate surface of the transparent substrate 210. The diameter of 802 can be made larger than before the process. That is, in the same layer as the mask 800 sandwiched between the transparent substrate 210 and the resist 900, the second opening is formed as a space extending in a circle around the first opening 902 in plan view from the normal direction of the transparent substrate 210. 802 will be formed. At this time, the diameter of each second opening 802 can be adjusted by adjusting the etching conditions such as the etching time of the isotropic etching process in the process.

  That is, in this process, the resist 900 common to the process of FIG. 10A described above is used, and the resist 900 is not subjected to patterning again, so that the shape of each first opening 902 is hardly changed. Further, the diameter of each second opening 802 is increased by patterning the mask 800 again. Therefore, for each second opening 802, when the diameter of the second opening 802 is increased with respect to the position before the process, it is possible to prevent the second opening 802 from being displaced. Thereby, after expanding the diameter of each 2nd opening part 802, it can prevent that the position with respect to the corresponding initial hole 212a shifts | deviates.

  As long as the etching in the step (b) of FIG. 10 is performed by anisotropic etching having directivity in the normal direction of the transparent substrate 210, it is not before the step (c) of FIG. It is also possible to obtain a shape similar to that shown in step (c) of FIG. 10 by performing step (b). In this case, the first opening 902 having a relatively small diameter and the second opening 802 having a large diameter are approximately the same as or slightly larger than the first opening 902 and smaller than the second opening 802. An initial hole 212 a having a diameter can be formed at a position facing the first opening 902.

  Thereafter, in the step of FIG. 11A, the resist 900 is removed by peeling or the like.

  Subsequently, in the process of FIG. 11B, by performing anisotropic dry etching processing on the transparent substrate 210 through the mask 800, each initial hole 212a is dug to open the dug hole 212b. To do. The digging holes 212b are continuous with the second openings 802 in the mask 800, and the first holes 212ab opened by transferring the shape of the second openings 802 to the transparent substrate 210, and the initial holes 212a. This shape is transferred to the transparent substrate 210 to form the second hole 212bb opened from the bottom of the first hole 212ab. In other words, the diameter of the first hole 212ab constituting the digging hole 212b is substantially equal to the diameter of the second opening 802, and the diameter of the second hole 212bb constituting the digging hole 212b is initially set. The diameter is approximately equal to the diameter of the hole 212a.

  In the process of FIG. 10C described above, the position of the first hole 212ab and the second hole 212bb in the dug hole 212b is prevented by preventing the displacement of the second opening 802 with respect to the initial hole 212a. Deviation can be prevented. In the step of FIG. 10C, the diameter of the corresponding first hole 212ab can be adjusted by adjusting the diameter of the second opening 802. In addition, in the process of FIG. 10B described above, by adjusting the shape of the initial hole 212a, the shape of the second hole 212bb that is continuously opened in the first hole 212ab is adjusted accordingly. can do.

  Further, in the step of FIG. 11B, the depth of the digging hole 212b along the direction perpendicular to the substrate surface of the transparent substrate 210 can be adjusted by adjusting the etching conditions such as the etching time. By adjusting the depth of the digging hole 212b in this way, the depth of the recess 212 along the direction perpendicular to the substrate surface of the transparent substrate 210, that is, the thickness of the microlens 500 can be adjusted. it can. At this time, by adjusting the depth of the digging hole 212b, the depth of the first hole 212ab in the digging hole 212b is also adjusted, and as shown in FIG. 3 (a) or FIG. 12 (a). The shape of the straight portion L0 that stands up toward the edge of the recess 212 can also be adjusted.

  After that, in the step of FIG. 11C, isotropic etching is performed again on the transparent substrate 210 through the mask 800, thereby digging each digging hole 212b to form a recess 212. At this time, the isotropic etching process may be performed by a dry etching process or a wet etching process.

  Here, with reference to FIG. 12A and FIG. 12B, formation of the recess 212 will be described. 12 (a) and 12 (b), the shape of the digging hole 212b before the opening of the concave portion 212 is shown by a two-dot chain line for any one concave portion 212. The center line of the microlens 500 to be formed is indicated by a one-dot chain line in the same manner as in FIG. 3A or 3B.

  In each digging hole 212b in FIG. 12 (a) or 12 (b), the transparent substrate starts from the bottom of the second hole 212bb as indicated by the arrow E1 or E3 by isotropic etching. By digging 210, the tip of the curved surface of the microlens 500 is formed, and as indicated by the arrow E2, the transparent substrate 210 is dug starting from the bottom of the first hole 212ab. A part of the lens curved surface of the microlens 500 that is continuous with the tip is formed. Further, as indicated by an arrow E4, an isotropic etching process is performed on the side wall of the first hole 212ab, and the transparent substrate 210 is dug.

  Therefore, in the cross-sectional portion of the recess 212 shown in FIG. 12A or 12B, the shape of the curved surface of the microlens 500 is symmetric with respect to the center line of the microlens 500 or with reference to the centerline. Corresponding to the flat bottom of the initial hole 212a, a flat portion is formed at the tip portion through which the center line passes. That is, a bottom surface in the shape of a flat circle having a diameter substantially equal to the diameter of the second opening 802 is formed below the recess 212 in FIG. 12A or 12B. Further, if attention is paid to the portion on the right side of the center line of the microlens 500 in the same figure, the shape of this portion is a flat portion at the tip of the microlens 500. And a curve portion defined by C2 is formed by continuous combination. These curvature centers O1 and O2 of the two kinds of curvature circles C1 and C2 correspond to the starting point of the etching process in the step of FIG. 11C, respectively.

  In addition, in FIG. 12A, in the cross-sectional portion including the diagonal line at the edge of the concave portion 212, one end side is continuously coupled to one of the two types of curved portions that are coupled to the flat portion of the lens curved surface of the microlens 500. At the same time, a straight line portion L0 that is cut from the one end side toward the edge of the recess 212 on the other end side is formed. In FIG. 12B, the lens curved surfaces of the adjacent microlenses 500 intersect with each other at the curved portion, so that the straight line portion L0 indicated by the dotted line in the drawing is not formed.

  Therefore, in the concave portion 212, the shape of the lens curved surface of the microlens 500 is formed as an aspheric lens curved surface that is rotationally symmetric with respect to the center line of the microlens 500. Then, by adjusting the etching conditions such as the etching time in the step of FIG. 11C, and in addition to this, by adjusting the shape of each digging hole 212b in the step of FIG. 11B as described above. The shape of the microlens 500 can be adjusted. That is, while adjusting the thickness of the microlens 500 and the curved surface of the microlens 500 in the concave portion 212, the shape of the tip portion through which the center line of the microlens 500 passes corresponds to the shape of the second hole 212bb, Corresponding to the shape of the first hole 212ab, the shape of the portion continuing to the tip can be adjusted. In addition, by adjusting the shape of the initial hole 212a opened in the process of FIG. 10B, the area occupied by the flat portion of the tip portion on the lens curved surface of the microlens 500 is reduced through the second hole 212bb. It is good to adjust so that. Thereby, the condensing capability of the microlens 500 can be further improved.

  Thereafter, in the step of FIG. 13A, the mask 800 is removed by etching or the like. Thereafter, in the step of FIG. 13B, a thermosetting transparent adhesive 230a is applied to the surface of the transparent substrate 210. At this time, the adhesive 230a is filled in each recess 212. Subsequently, in FIG. 13C, the cover glass 200 is pressed against the transparent substrate 210 to cure the adhesive 230 a to form the adhesive layer 230.

  Thereafter, by using the microlens substrate 20 formed in this way, an electro-optical device as already described with reference to FIGS. 4 to 8 is manufactured. Specifically, the light shielding film 23, the counter electrode 21, the alignment film 22, and the like are formed on the cover glass 200 of the microlens substrate 20. On the other hand, in addition to this, in addition to the data line 6a, the scanning line 11a, the TFT 30, etc., the pixel electrode 9a and further the data line driving circuit 101 etc. are formed in the peripheral region, and the TFT array substrate in which the alignment film 16 is formed. 10 and the microlens substrate 20 are opposed to each other and bonded together by a sealing material 52. Then, liquid crystal is sealed between the TFT array substrate 10 and the microlens substrate 20 to manufacture an electro-optical device.

  Therefore, according to the microlens manufacturing method according to the present embodiment, the number of masks required for forming the lens curved surface of the microlens 500 in each recess 212 can be reduced as compared with the prior art as described above. It becomes possible. Therefore, various processes required for forming and patterning such a mask can be reduced. As a result, the manufacturing process of the microlens 500 can be shortened.

  Furthermore, the lens curved surface of each microlens 500 can be stably formed in a predetermined shape, and the characteristics such as the focal position of each microlens 500 can be accurately controlled, and a plurality of microlenses with uniform characteristics can be obtained. 500 can be manufactured.

<2; Second Embodiment>
Next, a second embodiment according to the present invention will be described with reference to FIGS. In the second embodiment, the manufacturing process of the microlens is partially different from that of the first embodiment, and the shape of the microlens is different accordingly. In the following, the manufacturing process of the microlens according to the second embodiment will be described in detail only with respect to differences from the first embodiment, and overlapping descriptions of similar points will be omitted, and FIGS. May be described with reference to FIG.

  14 and 15 are process diagrams sequentially showing the configuration of the cross-sectional portion of the microlens substrate in each process of the manufacturing process according to the second embodiment. 14 and 15 both show the cross-sectional portion including the center line of the microlens 500. FIG. 16 (a) shows a section corresponding to the portion shown in FIG. 3 (a), and FIG. 13 (b) shows a section corresponding to the portion shown in FIG. 3 (b). It is sectional drawing for demonstrating the process which concerns.

  First, in the process of FIG. 14A, the control film 600 is formed on the transparent substrate 210. The control film 600 is made of a material that has an etching rate different from that of the transparent substrate 210, for example, an etching rate higher than that of the transparent substrate 210, particularly in an isotropic etching process when forming the concave portion 212, which will be described later. Formed by material. The control film 600 is formed by vapor deposition such as CVD, sputtering, coating, coating, printing, thermal oxidation, or the like.

  Thereafter, a mask 800 and a resist 900 are formed on the transparent substrate 210 on the upper layer side of the control film 600 by the same procedure as that of the first embodiment, and further patterned to form the second opening 802 and The first opening 902 is opened.

  Thereafter, in the step of FIG. 14B, as in the first embodiment, the transparent substrate 210 and the control film 600 are subjected to the second etching process to open the initial holes 212a.

  Thereafter, in the step of FIG. 14C, similarly to the first embodiment, the mask 800 is patterned to widen the diameters of the second openings 802.

  Thereafter, after removing the resist 900 by the same procedure as that of the first embodiment, in the step of FIG. 15A, each of the transparent substrate 210 and the control film 600 is subjected to anisotropic dry etching, The digging hole 212b is opened.

  Thereafter, in the process of FIG. 15B, each recess 212 is formed by performing an isotropic etching process on the transparent substrate 210 and the control film 600 in the same procedure as in the first embodiment.

  Here, as shown in FIG. 16A, for the cross-sectional portion including the diagonal line at the edge of the concave portion 212, in the step of FIG. 15B, in the opening in which the concave portion 212 is formed, this opening is transparent. The etching rate of the substrate 210 is different from the etching rate of the control film 600 that defines the edge of the opening. More specifically, for example, in the opening in which the recess 212 is formed, the etching rate of the control film 600 that defines the edge of the opening is larger than the etching rate of the transparent substrate 210 that defines the opening.

  As a result, the shape of the lens curved surface of the microlens 500 at the edge of each recess 212 can be further adjusted, and the degree of freedom in designing the microlens can be increased.

  More specifically, as shown in FIG. 16A, the shape of the edge of each recess 212 is indicated by a dotted line in the figure, and the control film 600 is not formed as in the first embodiment. Compared to the shape in the case of the microlens 500, the inclination from the bottom to the edge of the concave portion 212 along the lens curved surface of the microlens 500 can be formed to have a gentle shape.

  Note that, as shown in FIG. 16B, the lens curved surfaces of the microlenses 500 adjacent to each other in the horizontal direction or the vertical direction described with reference to FIG. The straight line portion L0 indicated by the dotted line and the gentle inclined portion continuing to the straight line portion L0 are not formed.

  Thereafter, the microlens substrate 20 is manufactured by the same procedure as in the first embodiment.

<3: 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. 17 is a schematic cross-sectional view of the projection type color display device.

  In FIG. 17, a liquid crystal projector 1100 as 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 embodiment, and can be appropriately changed within the scope of the invention or the concept that can be read from the entire claims and the specification, and the microlens with such a change can be changed. A manufacturing method, a microlens substrate, an electro-optical device including the microlens substrate, a manufacturing method thereof, and an 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 an enlarged portion related to four microlenses in the microlens substrate, and FIG. 2B is a partially enlarged view showing a configuration of an arbitrary microlens. It is a top view. 3A is an enlarged cross-sectional view showing the configuration of the FF ′ cross-section portion of FIG. 2B, and FIG. 3B is the configuration of the JJ ′ cross-section portion of FIG. 2B. FIG. It is a top view which shows the whole structure of an electro-optical apparatus. It is H-H 'sectional drawing of FIG. 3 is an equivalent circuit of various elements and wirings in a plurality of pixels formed in a matrix that forms an image display region of an electro-optical device. 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 sectional drawing for demonstrating the function of each micro lens about a some pixel. It is process drawing (the 1) which shows the structure of the cross-sectional part of the microlens substrate in each process of a manufacturing process later on. It is process drawing (the 2) which shows the structure of the cross-sectional part of the microlens board | substrate in each process of a manufacturing process later on. It is process drawing (the 3) which shows the structure of the cross-sectional part of the microlens substrate in each process of a manufacturing process later on. FIG. 12A shows a process related to the formation of the recesses for the cross section corresponding to the part shown in FIG. 3A, and FIG. 12B shows the process corresponding to the part shown in FIG. It is sectional drawing for demonstrating. It is process drawing (the 4) which shows the structure of the cross-sectional part of the microlens substrate in each process of a manufacturing process later on. It is process drawing (the 1) which shows the structure of the cross-sectional part of the micro lens substrate in each process of the manufacturing process which concerns on 2nd embodiment later on. It is process drawing (the 2) which shows the structure of the cross-sectional part of the microlens substrate in each process of the manufacturing process which concerns on 2nd Embodiment later on. FIG. 16A shows a process related to the formation of the recesses for the cross section corresponding to the part shown in FIG. 3A, and FIG. 13B shows the process corresponding to the part shown in FIG. It is sectional drawing for demonstrating. It is a schematic sectional view of a projection type color display device.

Explanation of symbols

  20a ... Lens formation region, 210 ... Transparent substrate, 212 ... Recess, 230 ... Adhesive layer, 500 ... Microlens, 800 ... Mask, 802 ... Second opening, 900 ... Resist, 902 ... First opening, 212a ... Initial Hole, 212b ... digging hole, 212ab ... first hole, 212bb ... second hole

Claims (8)

A first step of forming a mask on the substrate;
A second step of forming a resist on the mask;
A third step of arranging and opening a plurality of first openings in a predetermined pattern by patterning in the resist;
A fourth step of opening a plurality of second openings by performing a first etching process on the mask through the plurality of first openings;
A fifth step of opening a plurality of initial holes by performing a second etching process on the substrate through the plurality of first openings and the plurality of second openings;
After the fifth step, a sixth step of widening the diameter of each of the plurality of second openings by applying an isotropic etching process to the mask through the plurality of first openings. ,
A seventh step of removing the resist after the sixth step;
After the seventh step, an anisotropic etching process is performed on the substrate through the plurality of second openings to dig up the initial hole and correspond to the second openings. An eighth step of opening a plurality of digging holes each of a first hole that is opened and a second hole that is opened at the bottom of the first hole;
After the eighth step, the substrate is subjected to an isotropic etching process through the plurality of second openings to dig the plurality of digging holes, respectively, so that the cross-sectional shape is a straight line and a plurality of digging holes. A ninth step of forming a plurality of recesses made of a curve;
A tenth step of removing the mask after the ninth step;
And a eleventh step of forming a microlens by filling the concave portion with a transparent material after the tenth step. In the fourth step, as the first etching process, anisotropic etching having directivity in a direction intersecting the substrate is performed,
The method for manufacturing a microlens according to claim 1, wherein in the fifth step, anisotropic etching having directivity in a direction intersecting the substrate is performed as the second etching process. Before the first step, further includes a twelfth step of forming a control film on the substrate for controlling the shape of the concave portion,
In the fifth step, the second etching process is performed on the control film in addition to the substrate,
In the eighth step, the anisotropic etching process is performed on the control film in addition to the substrate,
The method of manufacturing a microlens according to claim 1, wherein in the ninth step, the isotropic etching process is performed on the control film in addition to the substrate. 4. The micro of claim 3, wherein in the twelfth step, the control film is formed of a material having an etching rate larger than that of the substrate in the isotropic etching process in the ninth step. Lens manufacturing method. A step of forming a microlens by the method of manufacturing a microlens according to any one of claims 1 to 4,
Forming a display electrode facing the microlens;
And a step of forming at least one of a wiring and an electronic element by being electrically connected to the display electrode. The front end portion through which the center line of the microlens passes has a flat portion that is flat along a plane intersecting the center line, and the shape in the cross section including the center line has the same radius of curvature and the center is the center. Two or more curves, which are at different positions on the line, are continuously coupled from the flat portion, and a plurality of concave portions having lens curved surfaces of the microlenses that are rotationally symmetric about the center line are opened. A substrate,
A transparent member that fills each of the plurality of recesses and forms the microlens,
At least a part of each of the plurality of recesses is a straight portion in which the shape in the cross section is continuous from the arcuate curve toward the edge located on the side opposite to the center line and intersects the surface of the substrate. A microlens substrate, comprising: A microlens substrate according to claim 6;
A display electrode facing the microlens;
An electro-optical device comprising: at least one of a wiring and an electronic element electrically connected to the display electrode.   An electronic apparatus comprising the electro-optical device according to claim 7.

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