JP2015203744A - Electro-optic device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electro-optic device and electronic equipment, in which use efficiency of light can be improved and thereby bright display and a good contrast can be obtained.SOLUTION: The electro-optic device includes: an element substrate 20; a counter substrate 30 disposed to oppose to the element substrate 20; a liquid crystal layer 40 disposed between the element substrate 20 and the counter substrate 30; a light-shielding part S that is composed of a plurality of light-shielding layers 22, 26, 32 disposed on the element substrate 20 and on the counter substrate 30 and has an opening T corresponding to each of a plurality of pixels P; and a plurality of microlenses ML1 disposed on at least either of the element substrate 20 and the counter substrate 30 and respectively corresponding to the plurality of pixels P. Each of the plurality of microlenses ML1 has a flat portion 12a in a center portion thereof, with the circumference of the flat portion 12a disposed in the opening T.

Description

  The present invention relates to an electro-optical device and an electronic apparatus.

  There is known an electro-optical device including an electro-optical material (for example, liquid crystal) between an element substrate and a counter substrate. Examples of the electro-optical device include a liquid crystal device used as a liquid crystal light valve of a projector. Such a liquid crystal device is required to realize high light utilization efficiency. Therefore, for example, a microlens array is provided on at least one of the element substrate and the counter substrate of the liquid crystal device, and among the light incident on the liquid crystal device, the light that is shielded by the light shielding layer is condensed by the microlens to be within the pixel opening. There is known a configuration for improving the light use efficiency in a liquid crystal device by making it incident on the light (see, for example, Patent Document 1).

  In the microlens array of the liquid crystal device described in Patent Document 1, a plurality of curved concave portions provided on the surface of a substrate made of quartz or the like are embedded with a lens layer (resin material) having a refractive index different from that of the substrate. It is formed. Each microlens has a convex portion formed of a curved surface, and collects incident light toward the opening (opening region) of each pixel. Then, when the opening of each pixel has an asymmetric shape with respect to one line, it is incident by arranging the center of each microlens so as to coincide with the center of gravity of the opening of each pixel. Of the light, the light traveling toward the opening is increased, and the light traveling toward the light shielding portion (non-opening region) is decreased.

JP 2009-69570 A

  By the way, in the microlens in which the convex portion has a curved surface, the light incident on the entire region of the microlens is collected toward the focal point of the microlens. For this reason, even if the light incident on the microlens is parallel light, the angle variation of the light incident on the liquid crystal layer through the microlens with respect to the alignment direction of the liquid crystal becomes large, and the contrast of the liquid crystal device decreases. There is a fear. Further, since the condensed light is diffused after passing through the focal point, the light emitted from the liquid crystal device is diffused, and as a result, the light use efficiency may be reduced. On the other hand, if a flat part is provided at the center of the microlens, incident light (parallel light) incident on the flat part goes straight as it is and enters the liquid crystal layer. In addition, diffusion of light emitted from the liquid crystal device can be suppressed. In addition, by providing a flat portion at the center of the microlens, that is, by providing a flat portion in the concave portion formed on the surface of the substrate, the depth of the concave portion can be reduced compared to the case of forming a curved concave portion. It is possible to reduce the manufacturing load required for forming the recesses and filling the recesses.

  On the other hand, in such a microlens having a flat portion at the center, the light incident on the flat portion goes straight as it is, and therefore, depending on the positional relationship between the opening of the pixel and the flat portion of the microlens, the straight light is blocked. There is a case where it is blocked by the portion or the distribution of illuminance in the opening portion is biased. In such a case, there is a possibility that the light use efficiency in the liquid crystal device is lowered and the brightness of the displayed image is varied. In particular, when the opening of each pixel has an asymmetric shape with respect to one line, the above-described problem is likely to occur. Therefore, a flat portion of the microlens is preferably used with respect to the opening of the pixel. It is desirable to arrange it at a position. However, Patent Document 1 does not disclose or suggest any configuration of a microlens having a flat portion at the center. According to the present invention, in a configuration in which a flat portion is provided at the center portion of the microlens, the light utilization efficiency in the electro-optical device is obtained by arranging the microlens (flat portion) at a suitable position regardless of the shape of the opening of the pixel. And to improve contrast.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 An electro-optical device according to this application example includes a first substrate, a second substrate arranged to face the first substrate, the first substrate, and the second substrate. A light-shielding portion that includes an electro-optic layer disposed between the substrate and a plurality of light-shielding layers disposed on the first substrate and the second substrate, and has an opening corresponding to each of the plurality of pixels. And a plurality of microlenses arranged corresponding to each of the plurality of pixels on at least one of the first substrate and the second substrate, each of the plurality of microlenses having a central portion A flat portion, and the periphery of the flat portion is disposed in the opening.

  According to the configuration of this application example, each of the plurality of microlenses arranged corresponding to each of the plurality of pixels has a flat portion at the center, and the periphery of the flat portion is arranged in the opening. That is, the entire area of the flat portion that does not have the light collecting function is disposed in the opening. Therefore, among the light incident on the microlens along the normal direction of the surface of the substrate on which the microlens is disposed, the light incident on the flat portion is not refracted and passes through the microlens as it is to the pixel opening. Since the light is incident, variation in the angle of light incident on the electro-optical layer is suppressed, and diffusion of light emitted from the electro-optical device is suppressed. In addition, since the entire area of the flat part is disposed in the opening, the light that has entered the flat part and passed through the microlens is incident on the electro-optic layer without being blocked by the light-shielding part, and is emitted from the electro-optical device. Is done. Accordingly, it is possible to improve light use efficiency and contrast in the electro-optical device.

  Application Example 2 In the electro-optical device according to the application example described above, the light shielding portion includes a portion extending in a first direction and a portion extending in a second direction intersecting the first direction. And the opening has an asymmetric planar shape with respect to a straight line along at least one of the first direction and the second direction, and the plurality of microlenses Each is preferably arranged so that the center of the flat portion overlaps the design center of gravity of the opening.

  According to the configuration of this application example, the opening has a planar shape that is asymmetric with respect to a straight line along at least one of the first direction and the second direction. Therefore, when the microlens is arranged so that the center of the flat part coincides with the center of the pixel (intersection of diagonal lines connecting the diagonals of the pixels), the position of the flat part in the opening is biased, There may be a bias in the distribution of illuminance. Here, according to the configuration of this application example, the microlens is arranged so that the center of the flat portion overlaps the design center of gravity of the opening. Therefore, the uneven position of the flat portion in the opening can be alleviated. As a result, the uneven distribution of the illuminance distribution in the opening can be suppressed, so that the brightness of the image displayed by the electro-optical device can be made more uniform.

  Application Example 3 In the electro-optical device according to the application example described above, each of the plurality of microlenses includes a curved surface portion arranged to surround the flat portion, and includes the first direction and the first direction. It is preferable that the difference between the diameter of the flat portion and the diameter of the opening in the direction of 2 is within 6 μm ± 0.5 μm.

  According to the configuration of this application example, each of the plurality of microlenses has a curved surface portion disposed so as to surround the flat portion. Therefore, the light incident on the curved surface portion around the flat portion among the light incident on the microlens is collected toward the opening. Here, if the area of the entire microlens is the same, the larger the difference between the diameter (width) of the flat portion and the diameter (width) of the opening, the smaller the area of the flat portion with respect to the area of the opening. Therefore, the area of the curved surface portion in the microlens is relatively large. As a result, the amount of light traveling straight decreases and the amount of light collected toward the opening increases, so that the variation in the angle of light incident on the electro-optic layer increases and the amount of diffused light decreases. Become more. On the other hand, the smaller the difference between the diameter (width) of the flat part and the diameter (width) of the opening, the larger the area of the flat part, so that the area of the curved surface part in the microlens becomes relatively small. When the area of the curved surface portion is reduced, the amount of light collected toward the opening is reduced, and the amount of light blocked by the light shielding portion is increased, so that the light use efficiency is lowered. Here, according to the configuration of the present application example, the difference between the diameter (width) of the flat portion and the diameter (width) of the opening is within 6 μm ± 0.5 μm. The area of the part can be set within a suitable range. Further, when a microphone lens is provided on one substrate and a light-shielding portion is provided on the other substrate, the difference between the diameter (width) of the flat portion and the diameter (width) of the opening is 6 μm ± 0.5 μm. By setting it within the range, even when the relative displacement between one substrate and the other substrate occurs, the entire region of the flat portion can be arranged in the opening.

  Application Example 4 In the electro-optical device according to the application example, it is preferable that the flat portion has a substantially rectangular shape in plan view.

  According to the configuration of this application example, since the flat portion is substantially rectangular, if the shape of the pixel is also substantially rectangular, the width of the portion including the curved portion outside the flat portion of the microphone lens is the intersection of the pixels. Are substantially the same in the directions along the two sides (the first direction and the second direction). On the other hand, when the flat portion has a shape other than a rectangle, such as a substantially circular shape, and the shape of the pixel is a substantially rectangular shape, the portion including the curved portion outside the flat portion in the direction along the two intersecting sides of the pixel The variation in the width of the is increased. Therefore, by making the flat portion substantially rectangular, the outer portion of the flat portion is made more uniform along the outer shape of the substantially rectangular shape of the pixel than when the flat portion is a shape other than a rectangle such as a circle. Since they can be arranged, it is possible to further improve the light utilization efficiency and contrast in the electro-optical device.

  Application Example 5 In the electro-optical device according to the application example described above, it is preferable that the outer edge of the microlens is disposed so as to overlap the light shielding portion in plan view.

  According to the configuration of this application example, the outer edge of the microlens is disposed so as to overlap the light shielding portion in plan view. Therefore, by arranging the microlens so that the center of the flat portion overlaps the design center of gravity of the opening, even if the boundary between adjacent microlenses deviates from the boundary between adjacent pixels, The boundary is not placed in the opening. Thereby, it can suppress arrange | positioning so that the microlens of an adjacent pixel may enter in the opening part of one pixel.

  Application Example 6 An electronic apparatus according to this application example includes the electro-optical device according to the application example described above.

  According to the configuration of this application example, it is possible to provide an electronic device having a bright display and excellent contrast.

FIG. 2 is a schematic plan view showing the configuration of the liquid crystal device according to the embodiment. FIG. 3 is an equivalent circuit diagram illustrating an electrical configuration of the liquid crystal device according to the embodiment. FIG. 2 is a schematic cross-sectional view illustrating a configuration of a liquid crystal device according to the present embodiment. FIG. 3 is a schematic plan view showing a light shielding portion and a pixel opening of the liquid crystal device according to the embodiment. FIG. 2 is a schematic plan view showing a configuration of a microlens according to the present embodiment. FIG. 3 is a schematic cross-sectional view illustrating a configuration of a microlens according to the present embodiment. FIG. 3 is a schematic plan view showing a positional relationship between pixel apertures and microlenses of the liquid crystal device according to the embodiment. FIG. 5 is a schematic cross-sectional view showing a method for manufacturing a microlens array substrate according to the present embodiment. FIG. 5 is a schematic cross-sectional view showing a method for manufacturing a microlens array substrate according to the present embodiment. Schematic which shows the structure of the projector as an electronic device which concerns on this embodiment. FIG. 6 is a schematic plan view showing a configuration of a microlens according to Modification Example 1. FIG. 6 is a schematic cross-sectional view showing a configuration of a microlens according to Modification Example 1.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Embodiments of the invention are described below with reference to the drawings. The drawings to be used are appropriately enlarged, reduced or exaggerated so that the part to be described can be recognized. In addition, illustrations of components other than those necessary for the description may be omitted.

  In the following embodiments, for example, when “on the substrate” is described, the substrate is disposed so as to be in contact with the substrate, or is disposed on the substrate via another component, or the substrate. It is assumed that a part is arranged so as to be in contact with each other and a part is arranged via another component.

<Electro-optical device>
Here, an active matrix liquid crystal device including a thin film transistor (TFT) as a pixel switching element will be described as an example of the electro-optical device. This liquid crystal device can be suitably used, for example, as a light modulation element (liquid crystal light valve) of a projection display device (projector) described later.

  First, a liquid crystal device as an electro-optical device according to the present embodiment will be described with reference to FIGS. 1, 2, 3, and 4. FIG. 1 is a schematic plan view showing the configuration of the liquid crystal device according to the present embodiment. FIG. 2 is an equivalent circuit diagram showing an electrical configuration of the liquid crystal device according to the present embodiment. FIG. 3 is a schematic cross-sectional view showing the configuration of the liquid crystal device according to the present embodiment. Specifically, FIG. 3 is a schematic cross-sectional view taken along the line A-A ′ of FIG. 1. FIG. 4 is a schematic plan view showing the light shielding portion and the pixel opening of the liquid crystal device according to the present embodiment.

  As shown in FIGS. 1 and 3, the liquid crystal device 1 according to the present embodiment includes an element substrate 20 as a first substrate, a counter substrate 30 as a second substrate disposed to face the element substrate 20, and A sealing material 42 and a liquid crystal layer 40 as an electro-optic layer are provided. As shown in FIG. 1, the element substrate 20 is larger than the counter substrate 30, and both the substrates are bonded together via a sealing material 42 arranged in a frame shape along the edge of the counter substrate 30.

  The liquid crystal layer 40 is composed of liquid crystal having positive or negative dielectric anisotropy enclosed in a space surrounded by the element substrate 20, the counter substrate 30, and the sealing material 42. The sealing material 42 is made of an adhesive such as a thermosetting or ultraviolet curable epoxy resin. Spacers (not shown) are mixed in the sealing material 42 to keep the distance between the element substrate 20 and the counter substrate 30 constant.

  Inside the sealing material 42 arranged in a frame shape, the light shielding layers 22 and 26 provided on the element substrate 20 and the light shielding layer 32 provided on the counter substrate 30 are arranged. The light shielding layers 22, 26, and 32 have a frame-like peripheral portion, and are formed of, for example, a light shielding metal or metal oxide. Inside the frame-shaped light shielding layers 22, 26, 32 is a display area E in which a plurality of pixels P are arranged. The pixels P have, for example, a substantially rectangular shape and are arranged in a matrix.

  The display area E is an area that substantially contributes to display in the liquid crystal device 1. The light shielding layers 22 and 26 provided on the element substrate 20 are provided, for example, in a lattice shape in the display region E so as to partition the opening regions of the plurality of pixels P in a plane. The liquid crystal device 1 may include a dummy area that is provided so as to surround the display area E and does not substantially contribute to display.

  A data line driving circuit 51 and a plurality of external connection terminals 54 are provided along the first side on the side opposite to the display region E of the sealing material 42 formed along the first side of the element substrate 20. An inspection circuit 53 is provided on the display region E side of the sealing material 42 along the other second side facing the first side. Further, a scanning line driving circuit 52 is provided inside the sealing material 42 along the other two sides that are orthogonal to these two sides and face each other.

  On the display area E side of the sealing material 42 on the second side where the inspection circuit 53 is provided, a plurality of wirings 55 that connect the two scanning line driving circuits 52 are provided. Wirings connected to the data line driving circuit 51 and the scanning line driving circuit 52 are connected to a plurality of external connection terminals 54. In addition, a vertical conduction portion 56 is provided at a corner portion of the counter substrate 30 to establish electrical continuity between the element substrate 20 and the counter substrate 30. The arrangement of the inspection circuit 53 is not limited to this, and the inspection circuit 53 may be provided at a position along the inner side of the seal material 42 between the data line driving circuit 51 and the display area E.

  In the following description, the direction along the first side where the data line driving circuit 51 is provided is defined as the X direction as the first direction, and the direction along the other two sides orthogonal to the first side and facing each other. Is the Y direction as the second direction. The X direction is a direction along the line A-A ′ in FIG. 1. The light shielding layers 22 and 26 are provided in a lattice shape along the X direction and the Y direction. The opening area of the pixel P is partitioned in a lattice shape by the light shielding layers 22 and 26 and is arranged in a matrix shape along the X direction and the Y direction.

  Further, a direction perpendicular to the X direction and the Y direction and directed upward in FIG. In this specification, viewing from the normal direction (Z direction) of the surface of the liquid crystal device 1 on the counter substrate 30 side is referred to as “plan view”.

  As shown in FIG. 2, in the display area E, the scanning lines 2 and the data lines 3 are formed so as to intersect with each other, and pixels P are provided corresponding to the intersections of the scanning lines 2 and the data lines 3. Yes. Each pixel P is provided with a pixel electrode 28 and a TFT 24 as a switching element.

  A source electrode (not shown) of the TFT 24 is electrically connected to the data line 3 extending from the data line driving circuit 51. Image signals (data signals) S1, S2,..., Sn are supplied to the data lines 3 from the data line driving circuit 51 (see FIG. 1) in a line sequential manner. A gate electrode (not shown) of the TFT 24 is a part of the scanning line 2 extending from the scanning line driving circuit 52. The scanning lines 2 are supplied with scanning signals G1, G2,..., Gm from the scanning line driving circuit 52 in a line sequential manner. A drain electrode (not shown) of the TFT 24 is electrically connected to the pixel electrode 28.

  The image signals S1, S2,..., Sn are written to the pixel electrode 28 through the data line 3 at a predetermined timing by turning on the TFT 24 for a certain period. The image signal of a predetermined level written in the liquid crystal layer 40 through the pixel electrode 28 in this manner is constant by the liquid crystal capacitance formed between the common electrode 34 (see FIG. 3) provided on the counter substrate 30. Hold for a period.

  In order to prevent the held image signals S1, S2,..., Sn from leaking, a storage capacitor 5 is formed between the capacitor line 4 formed along the scanning line 2 and the pixel electrode 28. Arranged in parallel with the liquid crystal capacitor. Thus, when a voltage signal is applied to the liquid crystal of each pixel P, the alignment state of the liquid crystal changes depending on the applied voltage level. As a result, the light incident on the liquid crystal layer 40 (see FIG. 3) is modulated to enable gradation display.

  The liquid crystal constituting the liquid crystal layer 40 modulates light and enables gradation display by changing the orientation and order of the molecular assembly depending on the applied voltage level. For example, in the normally white mode, the transmittance for incident light decreases according to the voltage applied in units of each pixel P. In the normally black mode, the transmittance for incident light increases in accordance with the voltage applied in units of each pixel P, and light having a contrast corresponding to an image signal is emitted from the liquid crystal device 1 as a whole.

  As shown in FIG. 3, the counter substrate 30 according to the present embodiment includes a microlens array substrate 10, an optical path length adjustment layer 31, a light shielding layer 32, a protective layer 33, a common electrode 34, and an alignment film 35. It has.

  The microlens array substrate 10 includes a substrate 11 and a lens layer 13. The substrate 11 is made of an inorganic material having optical transparency such as glass or quartz. A surface on the liquid crystal layer 40 side of the substrate 11 is defined as an upper surface 11a. The substrate 11 has a plurality of recesses 12 formed in the upper surface 11a. Each recess 12 is provided corresponding to the pixel P. The recess 12 has a flat portion 12a disposed at the center thereof. Details of the shape of the recess 12 will be described later.

The lens layer 13 is provided so as to cover the upper surface 11 a side of the substrate 11. The lens layer 13 is formed thicker than the depth of the recess 12 and is formed so as to embed the plurality of recesses 12. The lens layer 13 is made of a material having optical transparency and a refractive index different from that of the substrate 11. In the present embodiment, the lens layer 13 is made of an inorganic material having a higher refractive index than that of the substrate 11. Examples of such inorganic materials include SiON and Al ₂ O ₃ .

  By embedding the concave portion 12 with a material forming the lens layer 13, the convex microlens ML1 is configured. Accordingly, each microlens ML1 is provided corresponding to the pixel P. In addition, a microlens array MLA is configured by the plurality of microlenses ML1. The surface of the microlens array substrate 10, that is, the surface of the lens layer 13, is a substantially flat surface.

  The optical path length adjustment layer 31 is provided so as to cover the microlens array substrate 10. The optical path length adjusting layer 31 is light transmissive and is made of, for example, an inorganic material having substantially the same refractive index as that of the substrate 11. The optical path length adjustment layer 31 has a function of adjusting the distance from the microlens ML1 to the light shielding layer 26 to a desired value. Therefore, the layer thickness of the optical path length adjustment layer 31 is appropriately set based on optical conditions such as the focal length of the microlens ML1 corresponding to the wavelength of light.

  The light shielding layer 32 is provided on the optical path length adjustment layer 31. The light shielding layer 32 is provided so as to surround the periphery of the display area E (see FIG. 1) where the microlens ML1 is arranged, and is also provided in the display area E. The light shielding layer 32 is formed in, for example, a lattice shape so as to overlap the light shielding layer 22 and the light shielding layer 26 of the element substrate 20 in plan view, and has an opening 32a through which light is transmitted. The opening 32a is larger than, for example, an opening 22a of the light shielding layer 22 and an opening 26a of the light shielding layer 26 described later. The light shielding layer 32 may be formed in an island shape or a stripe shape. Further, the light shielding layer 32 may not be provided in the display area E.

  A protective layer 33 is provided so as to cover the optical path length adjusting layer 31 and the light shielding layer 32. The common electrode 34 is provided so as to cover the protective layer 33. The common electrode 34 is formed across a plurality of pixels P. The common electrode 34 is made of a transparent conductive film such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide). The protective layer 33 covers the light shielding layer 32 so that the surface of the common electrode 34 on the liquid crystal layer 40 side is flat, but directly covers the conductive light shielding layer 32 without providing the protective layer 33. The common electrode 34 may be formed. The alignment film 35 is provided so as to cover the common electrode 34.

  The element substrate 20 includes a substrate 21, a light shielding layer 22, an insulating layer 23, a TFT 24, an insulating layer 25, a light shielding layer 26, an insulating layer 27, a pixel electrode 28, and an alignment film 29. . The substrate 21 is made of a light transmissive material such as glass or quartz.

  The light shielding layer 22 is provided on the substrate 21. The light shielding layer 22 is formed in a lattice shape so as to overlap the upper light shielding layer 26 in plan view. The light shielding layer 22 and the light shielding layer 26 are disposed so as to sandwich the TFT 24 therebetween in the thickness direction (Z direction) of the element substrate 20. The light shielding layer 22 overlaps at least the channel region of the TFT 24 in plan view.

  Since the light shielding layer 22 and the light shielding layer 26 are provided, the incidence of light on the TFT 24 is suppressed, so that an increase in light leakage current in the TFT 24 and malfunction due to light can be suppressed. The region surrounded by the light shielding layer 22 (inside the opening 22a) and the region surrounded by the light shielding layer 26 (inside the opening 26a) overlap each other in plan view and become a region through which light is transmitted.

The insulating layer 23 is provided so as to cover the substrate 21 and the light shielding layer 22. The insulating layer 23 is made of an inorganic material such as SiO ₂ .

  The TFT 24 is provided on the insulating layer 23 and is disposed in a region overlapping the light shielding layer 22 and the light shielding layer 26 in plan view. The TFT 24 is a switching element that drives the pixel electrode 28. The TFT 24 includes a semiconductor layer, a gate electrode, a source electrode, and a drain electrode (not shown). A source region, a channel region, and a drain region are formed in the semiconductor layer. An LDD (Lightly Doped Drain) region may be formed at the interface between the channel region and the source region or between the channel region and the drain region.

  The gate electrode is formed on the element substrate 20 in a region overlapping with the channel region of the semiconductor layer in plan view via a part (gate insulating film) of the insulating layer 25. Although not shown, the gate electrode is electrically connected to the scanning line disposed on the lower layer side through a contact hole, and the TFT 24 is controlled to be turned on / off by applying a scanning signal.

The insulating layer 25 is provided so as to cover the insulating layer 23 and the TFT 24. The insulating layer 25 is made of an inorganic material such as SiO ₂ , for example. The insulating layer 25 includes a gate insulating film that insulates between the semiconductor layer of the TFT 24 and the gate electrode. The insulating layer 25 relieves surface irregularities caused by the TFT 24. A light shielding layer 26 is provided on the insulating layer 25. An insulating layer 27 made of an inorganic material is provided so as to cover the insulating layer 25 and the light shielding layer 26.

  The pixel electrode 28 is provided on the insulating layer 27 corresponding to the pixel P. The pixel electrode 28 is disposed in a region overlapping the opening 22 a of the light shielding layer 22 and the opening 26 a of the light shielding layer 26 in plan view. The pixel electrode 28 is made of a transparent conductive film such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide). The alignment film 29 is provided so as to cover the pixel electrode 28. The liquid crystal layer 40 is sealed between the alignment film 29 on the element substrate 20 side and the alignment film 35 on the counter substrate 30 side.

  Although not shown, an electrode, wiring, relay electrode, and storage capacitor 5 (see FIG. 2) for supplying an electrical signal to the TFT 24 are provided in a region overlapping the light shielding layer 22 and the light shielding layer 26 in plan view. A capacitive electrode or the like is provided. The light shielding layer 22 and the light shielding layer 26 may be configured to include these electrodes, wiring, relay electrodes, capacitor electrodes, and the like.

  In the liquid crystal device 1 according to the present embodiment, for example, light emitted from a light source or the like enters from the counter substrate 30 (microlens array substrate 10) side including the microlens ML1. Of the light incident on the microlens ML1 along the normal direction of the upper surface 11a from the substrate 11 side, the incident light L1 incident on the flat portion 12a travels straight through the microlens ML1, passes through the liquid crystal layer 40, and the element. Injected to the substrate 20 side.

  Incident incident on the outside of the flat portion 12a of the microlens ML1 (concave portion 12) (curved portion 12b and peripheral portion 12c shown in FIG. 6A) from a region overlapping the light shielding layer 26 in a plan view outside the incident light L1. If the light L2 goes straight as it is, it is shielded by the light shielding layer 26 as indicated by the broken line, but due to the difference in the refractive index between the substrate 11 and the lens layer 13, the planar center side of the pixel P Refracts to. In the liquid crystal device 1, the incident light L <b> 2 that is shielded by the light shielding layer 26 when traveling straight in this way is caused to enter the opening 26 a of the light shielding layer 26 by the action of the microlens ML <b> 1 and pass through the liquid crystal layer 40. Can do. As a result, since the amount of light emitted from the element substrate 20 side can be increased, the light utilization efficiency can be increased.

  Here, as in the liquid crystal device described in Patent Document 1, in a microlens having a convex portion formed of a curved surface, incident light is condensed toward the focal point of the microlens. Therefore, even if light is incident on the microlens along the normal direction of the surface of the substrate, the angle variation of the light passing through the microlens and entering the liquid crystal layer with respect to the alignment direction of the liquid crystal increases. Contrast may be reduced. Further, since the condensed light is diffused after passing through the focal point, the light emitted from the liquid crystal device is diffused, and as a result, the light use efficiency may be reduced.

  On the other hand, the liquid crystal device 1 according to the present embodiment has a flat portion 12a at the center of the microlens ML1 (recessed portion 12), and the light L1 incident on the flat portion 12a goes straight as it is to the liquid crystal layer. Therefore, the variation in the angle of light passing through the liquid crystal layer 40 is suppressed. Thereby, since the variation in the angle of light with respect to the alignment direction of the liquid crystal molecules of the liquid crystal layer 40 is suppressed, the contrast of the liquid crystal device 1 is improved. Further, since diffusion of light emitted from the liquid crystal device 1 is suppressed, for example, when the liquid crystal device 1 is used as a liquid crystal light valve of a projector, a bright display and a good contrast can be obtained.

  As shown by hatching in FIG. 4, the light shielding portions S are provided in a lattice shape in the display area E of the liquid crystal device 1. The light shielding portion S includes a light shielding layer 22, a light shielding layer 26, and a light shielding layer 32. In other words, at least one of the light shielding layer 22, the light shielding layer 26, and the light shielding layer 32 is disposed in the light shielding region S. The TFT 24 is disposed in a region overlapping the light shielding portion S in plan view. The light shielding portion S has an opening T corresponding to each of the plurality of pixels P. The opening T is an area where the opening 22a, the opening 26a, and the opening 32a overlap in plan view.

  The light shielding portion S has a portion extending in the X direction and a portion extending in the Y direction. In the present embodiment, the light-shielding portion S has a portion (a portion having a wide width) that protrudes toward the opening T in a portion extending in the Y direction. For example, a relay electrode or a capacitor electrode (not shown) is disposed on the protruding portion of the light shielding portion S. The opening T has a plane shape that is line-symmetric with respect to a straight line along the Y direction and non-axisymmetric with respect to a straight line along the X direction.

  A straight line dividing the opening T into two regions having the same area along the Y direction is defined as VL. The straight line VL is a straight line that passes through the center of the opening T in the X direction and is parallel to the Y direction. A straight line dividing the opening T into two regions (parts Ta and Tb described later) having the same area along the X direction is denoted by HL. The straight line HL is a straight line parallel to the X direction, but does not pass through the central portion of the opening T in the Y direction. Of the opening T, a portion on the + Y direction side divided by the straight line HL is Ta, and a portion on the −Y direction side is Tb.

  Each of the pixels P has a substantially rectangular planar shape and is arranged in a matrix at a predetermined arrangement pitch Pw (for example, 10 μm). FIG. 4 shows four pixels P adjacent to each other. Of the region of each pixel P, a region that overlaps the light shielding portion S in plan view is a non-opening region that does not transmit light, and a region that overlaps the opening T in plan view is an opening region that transmits light. In other words, the opening portion T of the pixel P is defined by the plurality of light shielding layers 22, 26, and 32 constituting the light shielding portion S.

  The pixels P adjacent in the X direction and the Y direction are arranged so as to contact each other. The boundary between adjacent pixels P in the X direction is located at the center in the width direction (X direction) of the portion extending in the Y direction of the light shielding portion S. The boundary between adjacent pixels P in the Y direction is located at the center in the width direction (Y direction) of the portion extending in the X direction of the light shielding portion S.

  Two diagonal lines connecting the diagonals of the pixel P are DLa and DLb, respectively. The intersection of the diagonal line DLa and the diagonal line DLb is the center Pc of the pixel P. The straight line VL described above passes through the center Pc of the pixel P. The direction along the diagonal line DLb is the W direction. The W direction is a direction intersecting the X direction and the Y direction on a plane constituted by the X direction and the Y direction.

  Each of the plurality of microlenses ML1 (recesses 12) is arranged at the same arrangement pitch Pw corresponding to each of the plurality of pixels P. Each of the microlenses ML1 (recesses 12) has a substantially rectangular planar shape. The outer shape of the microlens ML1 (concave portion 12) is a size inscribed in the pixel P. The four corners of the microlens ML1 (recessed portion 12) are preferably rounded. That is, it is preferable that the microlenses ML1 (concave portions 12) adjacent to each other in the direction along the diagonal lines DLa and DLb (W direction) are separated from each other.

  The microlenses ML1 (concave portions 12) adjacent to each other in the X direction and the Y direction are connected to each other, and the boundary thereof overlaps with the portion extending in the X direction or the portion extending in the Y direction of the light shielding portion S in plan view. Arranged in the area. The corners at the four corners of the microlens ML1 (recessed portion 12) are arranged at a portion where the portion extending in the X direction and the portion extending in the Y direction of the light shielding portion S intersect. That is, the outer edge of the microlens ML1 (recessed portion 12) is disposed so as to overlap the light shielding portion S in plan view.

  In the X direction, the boundary between the microlenses ML1 (recesses 12) adjacent to each other is arranged at substantially the same position as the boundary between the pixels P adjacent to each other. On the other hand, in the Y direction, the boundary between the adjacent microlenses ML1 (recesses 12) is arranged at a position different from the boundary between the adjacent pixels P. In the present embodiment, in the Y direction, the boundary between the microlenses ML1 (recesses 12) adjacent to each other is arranged at a position shifted by a distance G in the + Y direction with respect to the boundary between the adjacent pixels P. Yes.

  A flat portion 12a is disposed at the center of each of the microlenses ML1 (recessed portion 12). The flat portion 12a has a substantially rectangular planar shape. The peripheral edge of the flat portion 12 a is disposed in the opening T. That is, the entire area of the flat portion 12a is disposed in the opening T. In addition, the periphery of the flat part 12a refers to the boundary with the curved surface part 12b (refer FIG. 5) arrange | positioned around the flat part 12a.

  The center Lc of the flat portion 12a is at the same position as the center of the microlens ML1 (concave portion 12). And the center Lc of the flat part 12a is arrange | positioned so that it may overlap with the design gravity center Tc of the opening part T by planar view. The design center of gravity Tc of the opening T is the center of mass when the mass is uniformly distributed on the opening T, and in this embodiment, the opening T is divided into two parts Ta and Tb having the same area. Can be defined as the intersection of the straight line HL along the X direction and the straight line VL along the Y direction passing through the center Pc of the pixel P. More specifically, in the present embodiment, the center of gravity Tc is a position shifted from the center Pc of the pixel P by the distance G along the + Y direction.

<Micro lens>
Subsequently, the configuration and operation of the microlens ML1 according to the present embodiment will be described with reference to FIGS. 5, 6, and 7. FIG. FIG. 5 is a schematic plan view showing the configuration of the microlens according to the present embodiment. FIG. 6 is a schematic cross-sectional view showing the configuration of the microlens according to the present embodiment. FIG. 7 is a schematic plan view showing the positional relationship between the aperture of the pixel and the microlens of the liquid crystal device according to this embodiment.

  As shown in FIG. 5, the microlens ML <b> 1 according to the present embodiment includes a flat portion 12 a disposed at the center of the concave portion 12 constituting the convex shape, and a curved surface portion 12 b disposed so as to surround the flat portion 12 a. And a peripheral edge portion 12c arranged so as to surround the curved surface portion 12b. The flat portion 12a, the curved surface portion 12b, and the peripheral edge portion 12c are formed continuously.

  As described above, the flat portion 12a has a substantially rectangular planar shape. When the pixel P (see FIG. 4) is square, the flat portion 12a is also substantially square. The four corners of the flat portion 12a may be rounded as shown in FIG. The curved surface portion 12b and the peripheral edge portion 12c have a substantially rectangular planar shape, and the corners of the four corners are rounded. The curved surface portion 12b and the peripheral edge portion 12c have substantially the same width in the X direction and the Y direction except for the corners at the four corners.

  6A is a schematic cross-sectional view taken along line B-B ′ in FIG. 5, and FIG. 6B is a schematic cross-sectional view taken along line C-C ′ in FIG. 5. 5 is a straight line along the W direction passing through the center Lc of the flat portion 12a, and the CC ′ line in FIG. 5 is along the X direction passing through the center Lc of the flat portion 12a. It is a straight line. 6A and 6B are inverted in FIG. 3 in the vertical direction (Z direction). Therefore, although not shown, the light enters the microlens ML1 from the lower side to the upper side in FIGS. 6 (a) and 6 (b).

  As shown in FIGS. 6A and 6B, the flat portion 12 a is a bottom portion of the concave portion 12, and is a substantially flat surface substantially parallel to the upper surface 11 a of the substrate 11. The flat portion 12a does not have a light collecting function. Therefore, the light incident on the flat portion 12a along the normal direction of the upper surface 11a goes straight as it is. The curved surface portion 12b is provided continuously with the flat portion 12a and has an arcuate cross-sectional shape. The curved surface portion 12b has a light collecting function. The light incident on the curved surface portion 12b along the normal direction of the upper surface 11a is condensed toward the center Lc side of the flat portion 12a.

  The peripheral edge portion 12c is provided continuously with the curved surface portion 12b. In the W direction shown in FIG. 6A, the peripheral edge portion 12c is connected to the upper surface 11a, and the peripheral edge portions 12c between the adjacent concave portions 12 are separated from each other. In the X direction shown in FIG. 6B, the peripheral edge portions 12c of the adjacent concave portions 12 are connected to each other. The peripheral portion 12c is a so-called tapered surface that is inclined from the upper surface 11a toward the curved surface portion 12b. Therefore, the peripheral portion 12c does not have a light collecting function. Light incident on the peripheral portion 12c along the normal direction of the upper surface 11a is refracted toward the center Lc side of the flat portion 12a at substantially the same angle. Note that the inclination angle of the peripheral edge portion 12 c is appropriately set based on the difference between the refractive index of the substrate 11 and the refractive index of the lens layer 13.

  FIG. 6A shows a virtual curved surface 12d obtained by extending the curved surface portion 12b toward the upper surface 11a by a two-dot chain line. The virtual curved surface 12d is a substantially spherical curved surface formed by general isotropic etching. The angle formed between the tangent at the end of the virtual curved surface 12d and the upper surface 11a is, for example, an angle close to 90 °. Further, even in a conventional microlens having a convex portion formed of a curved surface, an angle formed by a tangent line at the end portion and the upper surface is an angle close to 90 °. When the angle formed between the tangent line at the end (peripheral edge) of the microlens and the upper surface is increased, the incident light is largely refracted and enters the opening T of the adjacent pixel P, or the incident light. May be totally reflected at the interface between the substrate and the lens layer.

  In the present embodiment, since the tapered peripheral portion 12c is provided around the curved surface portion 12b, the microlens ML1 is compared with the case where the end portion of the microlens is a substantially spherical curved surface (virtual curved surface 12d). The angle formed between the end portion (peripheral portion 12c) and the upper surface 11a can be reduced. Therefore, excessive refraction of light incident on the peripheral portion 12c is suppressed, and the difference between the angle of light refracted at the peripheral portion 12c and the angle of light refracted at the curved surface portion 12b can be reduced.

  FIG. 7A is a schematic plan view of the present embodiment in which the center Lc of the flat portion 12a of the microlens ML1 is arranged so as to overlap with the designed center of gravity Tc of the opening T in a plan view. FIG. 7B is a schematic plan view showing a case where the center Lc of the flat portion 12a of the microlens ML1 is arranged so as to overlap the center Pc of the opening T in a plan view.

  As shown in FIG. 7A, in the micro lens ML1, the entire region of the flat portion 12a is disposed in the opening T. As described above, the light incident on the flat portion 12a goes straight as it is, but since the entire area of the flat portion 12a is disposed in the opening T, the light incident on the flat portion 12a is blocked even if it goes straight as it is. The portion S is not shielded from light. Further, since the light incident on the flat portion 12a goes straight, the variation in the angle of the light incident on the liquid crystal layer 40 (see FIG. 3) is suppressed, and the diffusion of the light emitted from the liquid crystal layer 40 is suppressed.

  The curved surface portion 12b is provided outside the flat portion 12a so that at least an inner edge thereof is positioned in the opening T. In the present embodiment, as shown in FIG. 7A, the entire area of the curved surface portion 12b is disposed in the opening T, but the curved surface portion 12b is disposed so as to straddle the opening T and the light shielding portion S. May be. Even if the curved surface portion 12b overlaps the light shielding portion S in plan view, the light incident on the curved surface portion 12b is collected on the center Lc side of the flat portion 12a. Can be made incident in the opening T by the light collecting function of the curved surface portion 12b.

  The peripheral edge portion 12c is disposed outside the curved surface portion 12b so as to straddle the opening T and the light shielding portion S. Since the light incident on the peripheral portion 12c is refracted toward the center Lc side of the flat portion 12a, the light shielded by the light shielding portion S can be incident into the opening T if it goes straight as it is. In addition, since the light incident on the peripheral portion 12c is refracted at substantially the same angle, variations in the angle of the light incident on the liquid crystal layer 40 can be suppressed.

  As in the liquid crystal device described in Patent Document 1, in the microlens in which the convex portion is configured by a curved surface, the light incident on the entire region of the microlens is condensed toward the focal point of the microlens. The distribution of illuminance in the opening T is biased toward the center of the microlens. In addition, even if the light incident on the microlens is parallel light along the normal direction of the substrate surface, the variation in the angle of the light incident on the liquid crystal layer through the microlens with respect to the alignment direction of the liquid crystal increases. The contrast of the liquid crystal device may be reduced. Since the collected light is diffused after passing through the focal point, the light emitted from the liquid crystal device is diffused, and as a result, the use efficiency of the light may be reduced.

  In the microlens ML1 having the flat portion 12a and the tapered peripheral portion 12c as in the present embodiment, the illuminance distribution in the opening T of the pixel P is less biased than the conventional curved microlens. And become more uniform. In addition, since the variation in the angle of the light that passes through the microlens ML1 and enters the liquid crystal layer 40 with respect to the alignment direction of the liquid crystal is suppressed, the contrast of the liquid crystal device 1 is improved. Since the diffusion of light emitted from the liquid crystal layer 40 is suppressed, vignetting of light incident on the projection lens can be suppressed when the liquid crystal device 1 is used as a liquid crystal light valve of the projector. The contrast can be improved.

  In the present embodiment, as shown in FIG. 7A, the center of gravity Tc of the opening T of the pixel P is shifted from the center Pc of the pixel P by the distance G along the + Y direction. The center Lc of the flat portion 12a of the microlens ML1 is disposed so as to overlap the center of gravity Tc of the opening T in plan view. In other words, the microlens ML1 (flat portion 12a, curved surface portion 12b, peripheral edge portion 12c) is arranged so as to be shifted from the center Pc of the pixel P by the distance G along the + Y direction.

  Note that the outer edge of the microlens ML1 is disposed so as to overlap the light shielding portion S in plan view (see FIG. 4). Therefore, by arranging the center Lc of the flat portion 12a so as to overlap the design center of gravity Tc of the opening T, the boundary between the adjacent microlenses ML1 is shifted by the distance G from the boundary between the adjacent pixels P. However, the boundary of the microlens ML1 is not disposed in the opening T. That is, the microlens ML1 of the adjacent pixel P is not arranged so as to enter the opening T of one pixel P.

  By the way, as shown in FIG. 7B, a case is assumed where the center Lc of the microlens ML1 (flat portion 12a) is arranged so as to overlap the center Pc of the opening T in a plan view. In this case, among the entire areas of the flat portion 12a, the curved surface portion 12b, and the peripheral edge portion 12c of the microlens ML1, the opening T overlaps with the portion Ta on the + Y direction side divided by the straight line HL in a plan view. The area is different between the portion Tb on the −Y direction side and the portion overlapping in the plan view.

  Therefore, among the light that passes through the microlens ML1 and enters the opening T of the pixel P, the light that travels straight from the flat portion 12a, the light that is collected and incident on the curved surface portion 12b, and the peripheral portion 12c. The respective amounts of light that is refracted and incident are different between the portion Ta and the portion Tb having the same area. In other words, when the positions of the flat portion 12a, the curved surface portion 12b, and the peripheral edge portion 12c in the opening T of the pixel P are biased, the distribution of illuminance in the opening T of the pixel P is biased. .

  On the other hand, according to the configuration of the liquid crystal device 1 shown in FIG. 7A, the center Lc of the flat portion 12a of the microlens ML1 is arranged so as to overlap the design center of gravity Tc of the opening T. Therefore, in each of the flat portion 12a, the curved surface portion 12b, and the peripheral edge portion 12c, the area of the portion that overlaps the portion Ta in plan view and the portion that overlaps the portion Tb in plan view are equal. The deviation of the positions of the portion 12a, the curved surface portion 12b, and the peripheral edge portion 12c is suppressed. This suppresses the uneven distribution of the illuminance distribution in the opening T of the pixel P, so that the brightness of the image displayed by the electro-optical device can be made more uniform.

  Here, as shown to Fig.7 (a), let the diameter (width | variety) in the Y direction of the opening part T be F2. In addition, the diameter of the opening portion T on the side of the wide portion Ta in the X direction is also set to the same F2. And the flat part 12a shall be a substantially square, and let the diameter (width | variety) in the X direction and the Y direction be F1. In the present embodiment, the difference between the diameter F1 of the flat portion 12a and the diameter F2 of the opening T in the X direction and the Y direction is within 6 μm ± 0.5 μm.

  When the entire area of the micro lens ML1 is the same, the larger the difference between the diameter F1 of the flat portion 12a and the diameter F2 of the opening T, the smaller the area of the flat portion 12a with respect to the area of the opening T. The area of the curved surface portion 12b in ML1 is relatively large. As a result, the amount of light that goes straight into the opening T and enters the opening T is reduced, and the amount of light that is collected and incident toward the opening T is increased. Therefore, the angle variation of the light that enters the liquid crystal layer 40 is varied. Becomes larger.

  On the other hand, the smaller the difference between the diameter F1 of the flat part 12a and the diameter F2 of the opening T, the larger the area of the flat part 12a. Therefore, the area of the curved surface part 12b in the microlens ML1 becomes relatively small. Then, although the amount of light that travels straight into the opening T increases, the amount of light collected toward the opening T by the curved surface portion 12b decreases, so that the light is blocked by the light shielding portion S. Since the amount of light that increases, the light utilization efficiency decreases.

  According to the configuration of the liquid crystal device 1, since the difference between the diameter F1 of the flat portion 12a and the diameter F2 of the opening T is within 6 μm ± 0.5 μm, the area of the flat portion 12a in the microlens ML1 and the curved portion 12b The area can be set to a suitable range. Further, by setting the difference between the diameter F1 of the flat portion 12a and the diameter F2 of the opening T to be within 6 μm ± 0.5 μm, even if a misalignment between the counter substrate 30 and the element substrate 20 occurs, The entire region of the flat portion 12a can be disposed in the opening T.

<Method of manufacturing electro-optical device>
Next, a manufacturing method of the liquid crystal device 1 including the manufacturing method of the microlens array substrate 10 according to the present embodiment will be described. 8 and 9 are schematic cross-sectional views illustrating the method for manufacturing the microlens array substrate according to the present embodiment. Specifically, each of FIGS. 8 and 9 corresponds to a schematic cross-sectional view taken along the line BB ′ of FIG.

First, as shown in FIG. 8A, a control film 70 made of an oxide film such as SiO ₂ is formed on the upper surface 11a of the light-transmitting substrate 11 made of quartz. The control film 70 has an etching rate in isotropic etching different from that of the substrate 11, and the width direction (W direction, X direction, and the etching rate in the depth direction (Z direction) when the recess 12 is formed. It has a function of adjusting the etching rate in the Y direction).

  After forming the control film 70, the control film 70 is annealed at a predetermined temperature. The etching rate of the control film 70 varies depending on the annealing temperature. Therefore, the etching rate of the control film 70 can be adjusted by appropriately setting the temperature during annealing.

  Next, as shown in FIG. 8B, a mask layer 71 is formed on the control film 70. Subsequently, as shown in FIG. 8C, the mask layer 71 is patterned to form openings 72 in the mask layer 71. The opening 72 is substantially rectangular in plan view like the flat portion 12a in the recess 12 to be formed, and its shape and size are set to be substantially the same as the shape and size of the flat portion 12a. In other words, the shape and size of the flat portion 12 a in the formed recess 12 are determined by the shape and size of the opening 72 of the mask layer 71.

  The opening 72 is arranged such that the planar center of the opening 72 overlaps the designed center of gravity Tc of the opening T of the pixel P in plan view. That is, the planar center of the opening 72 is arranged at a position shifted in the + Y direction by the distance G with respect to the center Pc of the pixel P. The position of the planar center of the opening 72 is the center Lc of the flat portion 12a in the recess 12 to be formed.

  Next, as shown in FIG. 8D, isotropic etching is performed on the substrate 11 covered with the control film 70 through the opening 72 of the mask layer 71. For the isotropic etching, an etching solution (for example, hydrofluoric acid solution) is used such that the etching rate of the control film 70 is larger than the etching rate of the substrate 11. The control film 70 and the substrate 11 are etched from the opening 72 by isotropic etching, so that the opening 70 a is formed in the control film 70 and the recess 12 is formed in the substrate 11.

  Next, as shown in FIG. 9A, the recess 12 is enlarged as the isotropic etching progresses, and a portion of the recess 12 corresponding to the opening 72 of the mask layer 71 is substantially flat in plan view. It becomes a surface. Thereby, the flat part 12a is formed in the center part of the recessed part 12. FIG. Further, the curved surface portion 12b is formed so as to surround the flat portion 12a.

  Here, when the control film 70 is not provided between the substrate 11 and the mask layer 71, as shown by a broken line in FIG. 9A, the curved surface portion 12b is formed until it reaches the upper surface 11a of the substrate 11. Will be. In this embodiment, the control film 70 is provided between the substrate 11 and the mask layer 71, and the etching amount per unit time of the control film 70 in the isotropic etching is larger than the etching amount per unit time of the substrate 11. There are also many.

  Therefore, since the amount of expansion of the opening 70a of the control film 70 is larger than the amount of expansion of the recess 12 in the depth direction, the width direction of the recess 12 is also expanded as the opening 70a is expanded. Therefore, the etching amount per unit time in the width direction of the substrate 11 is larger than the etching amount per unit time in the depth direction. Thereby, the taper-shaped peripheral part 12c is formed so that the circumference | surroundings of the curved surface part 12b may be enclosed.

  As described above, the shape and size of the flat portion 12 a in the recess 12 can be controlled by the shape and size of the opening 72 of the mask layer 71. Further, the sizes of the curved surface portion 12 b and the peripheral edge portion 12 c in the concave portion 12 are controlled by the etching rate in the width direction with respect to the etching rate in the depth direction of the substrate 11, and the difference in this etching rate is caused when the control film 70 is annealed. It can be adjusted by the temperature setting.

  In this step, as shown in FIG. 9A, the isotropic etching is finished in a state where the adjacent recesses 12 are separated from each other. If isotropic etching is performed until adjacent recesses 12 are connected to each other, the mask layer 71 may be lifted off the substrate 11 and peeled off. In this embodiment, since the isotropic etching is finished with the upper surface 11a of the substrate 11 remaining between the adjacent recesses 12, the mask layer 71 can be supported until the isotropic etching is finished. . The outer shape (planar shape) of the formed recess 12 is a shape in which the planar shape of the opening 72 of the mask layer 71 is enlarged, that is, substantially rectangular, and the corners of the four corners are rounded.

  Next, as shown in FIG. 9B, after removing the mask layer 71 from the substrate 11, the substrate 11 has a light transmissive property so as to cover the upper surface 11 a side of the substrate 11 and embed the recess 12. The lens layer 13 is formed by depositing an inorganic material having a high refractive index. The lens layer 13 can be formed using, for example, a CVD method. Since the lens layer 13 is formed so as to embed the recess 12, the surface of the lens layer 13 has an uneven shape reflecting the unevenness caused by the recess 12 of the substrate 11.

  Subsequently, the lens layer 13 is flattened. In the flattening process, for example, a CMP (Chemical Mechanical Polishing) process or the like is used to polish a portion where the irregularities on the upper layer of the lens layer 13 are formed (portion above the two-dot chain line shown in FIG. 9B). As a result, the upper surface of the lens layer 13 is flattened.

  As a result of performing the flattening process on the lens layer 13, as shown in FIG. 9C, the upper surface of the lens layer 13 is flattened, and the microlens array substrate 10 is completed. In the microlens array substrate 10, the microlens ML1 is configured by embedding the material of the lens layer 13 in the recess 12.

  Although not shown in the drawings, in the conventional microlens having a convex portion formed of a curved surface, an opening smaller than that of the present embodiment is formed in the mask layer, and isotropic etching is performed on the substrate through the opening. By performing the treatment, the substrate is etched into a substantially spherical shape to form a curved concave portion. At this time, when the diameter of the concave portion to be formed is the same as the maximum diameter (the diameter in the W direction) of the concave portion 12 of the present embodiment, the depth of the curved concave portion is larger than the depth of the concave portion 12 of the present embodiment. Become deeper. Therefore, compared to the present embodiment, the amount of etching of the substrate and the amount of lens layer used to fill the recesses are increased, so the amount of polishing in the CMP processing step is also increased, and as a result, the man-hours in these steps are increased. Will be invited.

  According to the configuration of the microlens ML <b> 1 according to the present embodiment, the depth of the concave portion 12 is reduced by providing the flat portion 12 a at the central portion of the concave portion 12. Therefore, the number of steps and materials in the manufacturing process of the microlens array substrate 10 are reduced. The amount of use can be reduced. In addition, since the deposited lens layer 13 has a more uniform film thickness and a reduced surface irregularity, the surface flatness of the lens layer 13 can be improved.

  Subsequent steps will be described with reference to FIG. Next, an optical path length adjusting layer 31, a light shielding layer 32, a protective layer 33, a common electrode 34, and an alignment film 35 are sequentially formed on the microlens array substrate 10 by using a known technique. A substrate 30 is obtained. On the substrate 21, a light shielding layer 22, an insulating layer 23, a TFT 24, an insulating layer 25, a light shielding layer 26, an insulating layer 27, a pixel electrode 28, and an alignment film 29 are formed in this order. A substrate 20 is obtained.

  Next, a thermosetting or photo-curing adhesive is disposed between the element substrate 20 and the counter substrate 30 as a sealing material 42 (see FIG. 1) and cured, and the element substrate 20 and the counter substrate 30 are bonded. To do. The liquid crystal device 1 is completed by enclosing the liquid crystal in the space formed by the element substrate 20, the counter substrate 30, and the sealing material 42. Before bonding the element substrate 20 and the counter substrate 30, the liquid crystal may be disposed in a region surrounded by the sealing material 42.

  In the above-described manufacturing method, the planar center of the opening 72 formed in the mask layer 71 overlaps the design center of gravity Tc of the opening T of the pixel P in a plan view in the step shown in FIG. However, it may be arranged such that the planar center of the opening 72 overlaps the center Pc of the pixel P in plan view. When the planar center of the opening 72 formed in the mask layer 71 is arranged so as to overlap the center Pc of the pixel P in plan view, the counter substrate 30 including the microlens array substrate 10 manufactured by this method is used as the element. When bonding to the substrate 20, the counter substrate 30 (microlens ML1) may be disposed at a position shifted in the + Y direction by the distance G with respect to the element substrate 20 (pixel P). Thereby, in the completed liquid crystal device 1, the center Lc of the flat portion 12a of the microlens ML1 (recessed portion 12) can be arranged at a position overlapping the design center of gravity Tc of the opening T of the pixel P in plan view.

<Electronic equipment>
Next, an electronic apparatus according to the present embodiment will be described with reference to FIG. FIG. 10 is a schematic diagram illustrating a configuration of a projector as an electronic apparatus according to the present embodiment.

  As shown in FIG. 10, a projector (projection display device) 100 as an electronic apparatus according to this embodiment includes a polarization illumination device 110, two dichroic mirrors 104 and 105, and three reflection mirrors 106, 107, and 108. And five relay lenses 111, 112, 113, 114, 115, three liquid crystal light valves 121, 122, 123, a cross dichroic prism 116, and a projection lens 117.

  The polarization illumination device 110 includes a lamp unit 101 as a light source composed of a white light source such as an ultra-high pressure mercury lamp or a halogen lamp, an integrator lens 102, and a polarization conversion element 103. The lamp unit 101, the integrator lens 102, and the polarization conversion element 103 are disposed along the system optical axis Lx.

  The dichroic mirror 104 reflects red light (R) and transmits green light (G) and blue light (B) among the polarized light beams emitted from the polarization illumination device 110. Another dichroic mirror 105 reflects the green light (G) transmitted through the dichroic mirror 104 and transmits the blue light (B).

  The red light (R) reflected by the dichroic mirror 104 is reflected by the reflection mirror 106 and then enters the liquid crystal light valve 121 via the relay lens 115. The green light (G) reflected by the dichroic mirror 105 enters the liquid crystal light valve 122 via the relay lens 114. The blue light (B) transmitted through the dichroic mirror 105 is incident on the liquid crystal light valve 123 via a light guide system composed of three relay lenses 111, 112, 113 and two reflection mirrors 107, 108.

  The transmissive liquid crystal light valves 121, 122, and 123 as light modulation elements are disposed to face the incident surfaces of the cross dichroic prism 116 for each color light. The color light incident on the liquid crystal light valves 121, 122, 123 is modulated based on video information (video signal) and emitted toward the cross dichroic prism 116.

  The cross dichroic prism 116 is configured by bonding four right-angle prisms, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface thereof. Yes. The three color lights are synthesized by these dielectric multilayer films, and the light representing the color image is synthesized. The synthesized light is projected onto the screen 130 by the projection lens 117 which is a projection optical system, and the image is enlarged and displayed.

  The liquid crystal light valve 121 is the one to which the liquid crystal device 1 including the microlens ML1 of the above-described embodiment is applied. The liquid crystal light valve 121 is arranged with a gap between a pair of polarizing elements arranged in crossed Nicols on the incident side and emission side of colored light. The same applies to the other liquid crystal light valves 122 and 123.

  According to the configuration of the projector 100 according to the present embodiment, since the liquid crystal device 1 that can obtain a bright display and good contrast is provided even when the plurality of pixels P are arranged with high definition, the quality is high. A high and bright projector 100 can be provided.

  The above-described embodiments merely show one aspect of the present invention, and can be arbitrarily modified and applied within the scope of the present invention. As modifications, for example, the following can be considered.

(Modification 1)
The microlens ML1 according to the above embodiment has a configuration having the substantially rectangular flat portion 12a in the central portion of the recess 12, but the present invention is not limited to such a configuration. For example, the micro lens may have a substantially circular flat portion at the center of the concave portion. FIG. 11 is a schematic plan view showing the configuration of the microlens according to the first modification. FIG. 12 is a schematic cross-sectional view illustrating a configuration of a microlens according to the first modification. Constituent elements common to the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 11, the microlens array substrate 10 </ b> A according to the first modification includes a microlens ML <b> 2 configured with a recess 14. The recess 14 includes a flat portion 14a disposed at the center, a curved surface portion 14b disposed around the flat portion 14a, and a peripheral edge portion 14c disposed around the curved surface portion 14b. The outer shape of the microlens ML2 (recessed portion 14) is substantially rectangular, but the virtual outer shape 14d of the recessed portion 14 (peripheral portion 14c) is circular, for example, within the pixel P (see FIG. 7A). It is larger than the circumcircle and smaller than the circumcircle.

  The flat portion 14a is substantially circular, and a virtual outer shape 14d that is the outer shape of the flat portion 14a, the curved surface portion 14b, and the peripheral edge portion 14c is formed concentrically around the planar center Lc of the flat portion 14a. Yes. The center Lc of the microlens ML2 (flat portion 14a) is disposed so as to overlap with the designed center of gravity Tc of the opening T of the pixel P. In the microlens ML2, the outer shape of the flat portion 14a and the curved surface portion 14b is substantially circular, whereas the outer shape of the peripheral portion 14c (concave portion 14) is substantially rectangular. Therefore, the width of the peripheral portion 14c is X and Y directions. As the distance from the center increases, the value increases. Therefore, the variation in the width of the peripheral portion 14c is larger than that of the peripheral portion 12c of the microlens ML1.

  12A is a schematic cross-sectional view taken along line B-B ′ in FIG. 11, and FIG. 12B is a schematic cross-sectional view taken along line C-C ′ in FIG. 11. Since the virtual outer shape of the recess 14 is circular, the virtual cross-sectional shape in the X direction of the recess 14 indicated by a broken line in FIG. 12B is the cross-sectional shape in the W direction of the recess 14 shown in FIG. Will be the same. Therefore, the width of the peripheral portion 14c in the X direction (and the Y direction) is smaller than the width of the peripheral portion 12c of the microlens ML shown in FIG. Note that the microlens ML2 can be formed by forming the opening 72 in a substantially circular shape when forming the opening 72 in the mask layer 71 in the step shown in FIG. 8C.

  As shown in FIG. 11, also in the microlens ML2 according to the first modification, the entire area of the flat portion 14a is disposed in the opening T of the pixel P, and the center Lc of the microlens ML2 (flat portion 14a) is the opening. By arranging so as to overlap with the designed center of gravity Tc, it is possible to improve the light use efficiency and contrast in the liquid crystal device. However, in the microlens ML2, since the variation in the width of the peripheral edge portion 14c becomes large, the microlens ML1 having the substantially rectangular flat portion 12a is preferable.

(Modification 2)
The microlenses ML1 and ML2 according to the above-described embodiment and Modification 1 have a configuration including the tapered peripheral edge portions 12c and 14c on the outer edge side of the recesses 12 and 14, but the present invention is limited to such a form. Not. For example, the microlenses ML1 and ML2 may have a configuration in which the outer peripheral edges do not have the tapered peripheral portions 12c and 14c and the curved surface portions 12b and 14b are connected to the upper surface 11a of the substrate 11. Even in such a configuration, the entire regions of the flat portions 12a and 14a are arranged in the opening T, and the centers Lc of the flat portions 12a and 14a are arranged so as to overlap the design center of gravity Tc of the opening T. Thus, it is possible to improve the light use efficiency and contrast in the liquid crystal device. However, if the end part (peripheral part) of the microlens is a curved surface, the incident light may be greatly refracted or totally reflected. Therefore, the microlenses ML1 and ML2 having the peripheral parts 12c and 14c may be affected. Is preferred.

(Modification 3)
The manufacturing method of the microlens array substrate 10, 10 </ b> A according to the above-described embodiment and Modification 1 is a process of performing isotropic etching by providing the shape and size of the opening 72 of the mask layer 71 and the control film 70. Although the recesses 12 and 14 are formed by controlling the difference in the etching rate between the width direction and the depth direction, the present invention is not limited to such a form. For example, a resist layer is formed on the substrate 11, and the original shape of the recesses 12 and 14 is formed in the resist layer by exposure using a gray scale mask or multistage exposure. By performing anisotropic etching with the same etching selectivity, the shape of the recesses 12 and 14 can be transferred and formed on the substrate 11. In this case, the control film 70 is not necessary.

(Modification 4)
In the liquid crystal device 1 described above, the microlens array substrate 10 is provided on the counter substrate 30, but the present invention is not limited to such a form. For example, the element substrate 20 may include the microlens array substrate 10 (or 10A). Further, the microlens array substrate 10 (or 10A) may be provided on both the element substrate 20 and the counter substrate 30.

(Modification 5)
The electronic device to which the liquid crystal device 1 according to the above embodiment can be applied is not limited to the projector 100. The liquid crystal device 1 is, for example, a projection-type HUD (head-up display), a direct-view type HMD (head-mounted display), an electronic book, a personal computer, a digital still camera, a liquid crystal television, a viewfinder type, or a monitor direct-view type video. It can be suitably used as a display unit for information terminal devices such as recorders, car navigation systems, electronic notebooks, and POS.

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal device (electro-optical device) 12, 14 ... Recessed part, 12a, 14a ... Flat part, 12b, 14b ... Curved part, 12c, 14c ... Peripheral part, 20 ... Element substrate (first substrate), 22 ... Light shielding layer (light shielding part), 26 ... Light shielding layer (light shielding part), 30 ... Counter substrate (second substrate), 32 ... Light shielding layer (light shielding part), 40 ... Liquid crystal layer (electro-optical layer), 100 ... Projector ( Electronic device), ML1, ML2 ... microlens, P ... pixel, S ... light-shielding part, T ... opening.

Claims (6)

A first substrate;
A second substrate disposed to face the first substrate;
An electro-optic layer disposed between the first substrate and the second substrate;
A light-shielding portion composed of a plurality of light-shielding layers disposed on the first substrate and the second substrate, and having an opening corresponding to each of the plurality of pixels;
A plurality of microlenses arranged corresponding to each of the plurality of pixels on at least one of the first substrate and the second substrate;
Each of the plurality of microlenses has a flat portion at the center,
The electro-optical device according to claim 1, wherein a peripheral edge of the flat portion is disposed in the opening. The electro-optical device according to claim 1,
The light shielding portion includes a portion extending in a first direction and a portion extending in a second direction intersecting the first direction,
The opening has a planar shape asymmetric with respect to a straight line along at least one of the first direction and the second direction;
Each of the plurality of microlenses is arranged such that the center of the flat portion overlaps the design center of gravity of the opening. The electro-optical device according to claim 2,
Each of the plurality of microlenses has a curved surface portion disposed so as to surround the flat portion,
An electro-optical device, wherein a difference between the diameter of the flat portion and the diameter of the opening in the first direction and the second direction is within 6 μm ± 0.5 μm. The electro-optical device according to any one of claims 1 to 3,
The electro-optical device, wherein the flat portion has a substantially rectangular shape in plan view. The electro-optical device according to claim 1,
An electro-optical device, wherein an outer edge of the microlens is arranged so as to overlap with the light shielding portion in a plan view.   An electronic apparatus comprising the electro-optical device according to claim 1.

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