JP2018072756A - Microlens array substrate and method for manufacturing the same, electro-optical device and method for manufacturing the same, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microlens array substrate that reduces variations in brightness and contrast ratio even when the distance or the planar relationship between first lenses and second lenses varies, thereby stabilizing the quality and a method for manufacturing the same, an electro-optical device and a method for manufacturing the same, and an electronic apparatus.SOLUTION: A microlens array substrate 10 comprises: a substrate 11; microlenses ML1 arranged on the substrate 11; and microlenses ML2 arranged on the microlenses ML1 to be overlapped with the microlenses ML1 in plan view. The microlenses ML2 are each formed of a curved surface and have a center part 16a and a peripheral part 16b arranged on the outside of the center part 16a, and the curvature of the peripheral part 16b is smaller than the curvature of the center part 16a.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a microlens array substrate and a manufacturing method thereof, an electro-optical device and a manufacturing method thereof, and an electronic apparatus.

  There is known an electro-optical device including an electro-optical material such as 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 and an imaging device used as an imaging unit of a video camera. In the liquid crystal device, a light shielding portion is provided in a region where switching elements, wirings, and the like are arranged, and a part of incident light is shielded by the light shielding portion and is not used. Thus, a configuration is known in which at least one substrate is provided with a microlens to improve the light use efficiency in the electro-optical device (see, for example, Patent Document 1).

  The microlens array substrate described in Patent Literature 1 includes a first lens disposed on the light incident side and a second lens disposed on the light emission side. The first lens is configured by filling a recess formed in a substrate with an inorganic material having a refractive index larger than that of the substrate. The second lens is formed in a convex shape with an inorganic material having a refractive index higher than that of the substrate via a light transmitting layer (optical path length adjusting layer) between the second lens and the first lens. The cross-sectional shape of the first lens and the second lens is a semi-elliptical shape.

  In the microlens array substrate described in Patent Document 1, incident light is condensed to the center side of the lens by the first lens, and the light condensed by the first lens is further condensed by the second lens. Thereby, the light that is blocked by the light-shielding layer disposed at the boundary between the pixels out of the light that enters the liquid crystal light valve (electro-optical device) through the color filter substrate is incident into the opening of the pixel, The use efficiency of light in the electro-optical device is improved.

JP 2014-089230 A

  By the way, the distance between the first lens and the second lens is caused by, for example, a variation in film thickness when forming the lens layer or a variation in polishing amount when the surface of the lens layer is flattened. May vary. In such a case, the range of light collected and emitted by the first lens is large when close to the first lens, but decreases as the distance from the first lens increases. Therefore, the light collected by the first lens and incident on the second lens enters a wide range in the second lens when the first lens and the second lens are close to each other, and the first lens and the second lens When the distance is far, the light enters the narrow range in the second lens.

  Here, as described in Patent Document 1, in the conventional microlens array substrate in which the second lens has a semi-elliptical cross-sectional shape, the curvature of the peripheral portion is larger than the curvature of the central portion of the second lens. . Therefore, the incident angle of the light incident on the peripheral portion is larger and the variation of the incident angle is larger than the incident angle of the light incident on the central portion of the second lens. Therefore, when the light collected by the first lens is incident on a wide range in the second lens, more light is incident on the peripheral portion than when entering the narrow range in the second lens. The light emitted from the second lens contains a lot of light having a large inclination angle and a large variation in inclination angle. In addition, even if the distance between the first lens and the second lens is the same, if the planar positional relationship between the first lens and the second lens varies, the light incident on the central portion of the second lens and the peripheral portion The ratio of light incident on the light changes. Thus, when the distance between the first lens and the second lens and the planar positional relationship between the first lens and the second lens vary, the distribution range of the inclination angle of the light emitted from the microlens array substrate. However, there is a problem in that the brightness and contrast ratio of the electro-optical device vary and the display quality deteriorates and becomes unstable.

  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] A microlens array substrate according to this application example includes a substrate, a first microlens disposed on the substrate, and the first microlens and the plane on the first microlens. A second microlens arranged so as to overlap with each other, and the second microlens has a central portion made of a curved surface and a peripheral portion arranged outside the central portion. And the curvature of the said peripheral part is smaller than the curvature of the said center part, It is characterized by the above-mentioned.

  According to the configuration of this application example, the light incident from the substrate side is collected by the first microlens, is incident on the second microlens, is further condensed by the second microlens, and is the substrate. It is injected to the other side. Here, since the curvature of the peripheral part arranged outside the central part of the second microlens is smaller than the curvature of the central part, the peripheral part is larger than the curvature of the central part. The incident angle of light incident on is small, and the variation in incident angle is also small. Therefore, even when the amount of light incident on the peripheral portion of the second microlens increases, variation in the inclination angle of the light emitted from the second lens can be suppressed to a small value. Therefore, even if the distance between the first microlens and the second microlens and the planar positional relationship between the first microlens and the second microlens vary, the light emitted from the second microlens The inclination angle distribution range can be kept small. Accordingly, for example, when applied to an electro-optical device, it is possible to provide a microlens array substrate that has less variation in brightness and contrast ratio and can stabilize quality compared to a conventional microlens array substrate.

  Application Example 2 In the microlens array substrate according to the application example, it is preferable that the peripheral portion includes a tapered inclined surface.

  According to the configuration of this application example, the peripheral portion of the second microlens includes a tapered inclined surface. If the lens surface is a tapered inclined surface, the incident angle of light entering from the same direction will be almost the same, so the variation in the inclination angle of the light emitted from the periphery compared to when the lens surface is a curved surface Becomes smaller. Therefore, the distribution range of the inclination angle of the light emitted from the second microlens can be further reduced.

  Application Example 3 In the microlens array substrate according to the application example, the first microlens fills a concave portion provided in the substrate with a material having a refractive index larger than that of the substrate. The second microlens is made of a material having a refractive index larger than the refractive index of the substrate, and is formed in a convex shape that protrudes on the opposite side to the first microlens. It is preferable.

  According to the configuration of this application example, the convex first microlens that protrudes toward the substrate is made of a material having a refractive index larger than the refractive index of the substrate, and protrudes on the opposite side of the first microlens. A convex second microlens is formed. Therefore, when light is incident from the substrate side, the second microlens has a convex shape protruding toward the light emission side. Therefore, as compared with the case of a convex shape protruding toward the light incident side, the light incident on the peripheral portion of the second microlens from the first microlens side toward the outer side can be bent more strongly inwardly. it can. Thereby, the utilization efficiency of light can be improved more.

  Application Example 4 In the microlens array substrate according to the application example described above, it is preferable that the cross-sectional shape of the second microlens is substantially symmetric with respect to the vertex of the central portion.

  According to the configuration of this application example, since the cross-sectional shape of the second microlens is substantially symmetric with respect to the apex of the central portion, the light incident on the second microlens is changed from the same direction to the apex of the central portion. Light incident on symmetrical positions is refracted at substantially the same angle. Thereby, the variation in the inclination angle of the light emitted from the second microlens is reduced. Therefore, for example, when applied to an electro-optical device, it is possible to provide a microlens array substrate capable of suppressing variations in brightness and contrast ratio and making the brightness at the apertures of the pixels more uniform.

  Application Example 5 An electro-optical device according to this application example includes a switching element provided for each pixel, and a light shielding unit provided with an opening for each pixel so as to overlap the switching element in plan view. , A microlens array substrate of the above application example, a second substrate disposed so as to face the first substrate, the first substrate, and the second substrate An electro-optic layer disposed between the first microlens and the second microlens so as to overlap the opening of each pixel in plan view. It is characterized by.

  According to the configuration of this application example, in the electro-optical device, the distance between the first microlens and the second microlens and the planar positional relationship between the first microlens and the second microlens vary. Even in such a case, a microlens array substrate that can suppress variations in brightness and contrast ratio is provided. Therefore, it is possible to provide an electro-optical device that can display an image with stable quality with small variations in brightness and contrast ratio.

  Application Example 6 An electro-optical device according to this application example includes a first substrate including a light receiving element provided for each pixel, a light shielding portion having an opening for each pixel, and the application example described above. A second substrate including a microlens array substrate and disposed to face the first substrate, wherein the first microlens, the second microlens, and the light receiving element are It arrange | positions so that it may overlap with the said opening part for every pixel by planar view.

  According to the configuration of this application example, in the electro-optical device, the distance between the first microlens and the second microlens and the planar positional relationship between the first microlens and the second microlens vary. Even in such a case, a microlens array substrate that can suppress variations in brightness and contrast ratio is provided. Therefore, it is possible to provide an electro-optical device that can acquire an image with stable quality with small variations in brightness and contrast ratio.

  Application Example 7 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 that can display or acquire a stable image with small variations in brightness and contrast ratio.

  Application Example 8 A method for manufacturing a microlens array substrate according to this application example includes a step of forming a recess on the surface of the substrate and a refractive index greater than the refractive index of the substrate so as to fill the recess of the substrate. A first lens layer made of a material having a refractive index, and a material having a refractive index larger than the refractive index of the substrate on the first lens layer so as to overlap the concave portion in plan view. Forming a second lens layer having a convex portion constituted by a curved surface, and the convex portion has a central portion and a peripheral portion disposed outside the central portion. The curvature of the peripheral part is smaller than the curvature of the central part.

  According to the manufacturing method of this application example, on the substrate, a convex first microlens that protrudes toward the substrate, and a convex second microlens that protrudes on the opposite side of the first microlens, Can be formed. Since the curvature of the peripheral portion arranged outside the central portion of the second microlens is smaller than the curvature of the central portion, the second curvature from the substrate side is larger than the case where the curvature of the peripheral portion is larger than the curvature of the central portion. The incident angle of light incident on the periphery of the microlens is small, and the variation in incident angle is also small. Therefore, even when the amount of light incident on the peripheral portion of the second microlens increases, variation in the inclination angle of the light emitted from the second lens can be suppressed to a small value. Therefore, even if the distance between the first microlens and the second microlens and the planar positional relationship between the first microlens and the second microlens vary, the light emitted from the second microlens The inclination angle distribution range can be kept small. As a result, when applied to, for example, an electro-optical device, the microlens array substrate can be manufactured with stable quality with small variations in brightness and contrast ratio compared to conventional microlens array substrates.

  Application Example 9 A method for manufacturing an electro-optical device according to this application example includes the method for manufacturing a microlens array substrate according to the application example described above.

  According to the manufacturing method of this application example, even when the distance between the first microlens and the second microlens and the planar positional relationship between the first microlens and the second microlens vary, It is possible to manufacture an electro-optical device that can display or acquire an image with a stable quality with a small contrast ratio variation.

1 is a schematic plan view showing a configuration of a liquid crystal device according to a first embodiment. FIG. 2 is an equivalent circuit diagram illustrating an electrical configuration of the liquid crystal device according to the first embodiment. 1 is a schematic cross-sectional view illustrating a configuration of a liquid crystal device according to a first embodiment. FIG. 3 is a schematic cross-sectional view showing a cross-sectional shape of a second microlens according to the first embodiment. FIG. 4 is a schematic cross-sectional view showing an enlarged main part of two pixels in FIG. 3. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. FIG. 3 is a schematic cross-sectional view showing the method for manufacturing the microlens array substrate according to the first embodiment. Schematic which shows the structure of the projector as an electronic device which concerns on 1st Embodiment. The schematic sectional drawing which shows the manufacturing method of the micro lens array board | substrate which concerns on 2nd Embodiment. The schematic sectional drawing which shows the manufacturing method of the micro lens array board | substrate which concerns on 2nd Embodiment. The schematic sectional drawing which shows the manufacturing method of the micro lens array board | substrate which concerns on 2nd Embodiment. The schematic sectional drawing which shows the manufacturing method of the micro lens array board | substrate which concerns on 2nd Embodiment. The schematic sectional drawing which shows the manufacturing method of the micro lens array board | substrate which concerns on 2nd Embodiment. FIG. 6 is a schematic cross-sectional view showing a method for manufacturing a microlens array substrate according to a third embodiment. FIG. 6 is a schematic cross-sectional view showing a method for manufacturing a microlens array substrate according to a third embodiment. FIG. 6 is a schematic cross-sectional view showing a method for manufacturing a microlens array substrate according to a third embodiment. FIG. 6 is a schematic cross-sectional view showing a method for manufacturing a microlens array substrate according to a third embodiment. FIG. 6 is a schematic cross-sectional view showing a method for manufacturing a microlens array substrate according to a third embodiment. FIG. 10 is a schematic cross-sectional view illustrating a configuration of an imaging apparatus according to a fourth embodiment. Schematic which shows the structure of the video camera as an electronic device which concerns on 4th Embodiment. FIG. 6 is a schematic cross-sectional view showing enlarged and compared main portions of two pixels in a conventional microlens array substrate.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described 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.

(First embodiment)
<Electro-optical device>
In the first embodiment, as an electro-optical device, an active matrix liquid crystal device including a thin film transistor (TFT) as a pixel switching element will be described as an example. 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 first embodiment will be described with reference to FIGS. 1, 2, and 3. FIG. 1 is a schematic plan view showing the configuration of the liquid crystal device according to the first embodiment. FIG. 2 is an equivalent circuit diagram showing an electrical configuration of the liquid crystal device according to the first embodiment. FIG. 3 is a schematic cross-sectional view illustrating the configuration of the liquid crystal device according to the first embodiment. Specifically, FIG. 3 is a schematic cross-sectional view taken along the line A-A ′ of FIG. 1.

  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 pixel P has a substantially polygonal planar shape. 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 the X direction, and the direction along the other two sides orthogonal to the first side and facing each other is the Y 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 orthogonal to the X direction and the Y direction and directed toward the front 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 first embodiment includes a microlens array substrate 10, a light shielding layer 32, a protective layer 33, a common electrode 34, and an alignment film 35. The microlens array substrate 10 according to the first embodiment includes two stages of microlenses: a microlens ML1 as a first microlens and a microlens ML2 as a second microlens.

  The microlens array substrate 10 includes a substrate 11, a lens layer 13 as a first lens layer, a lens layer 15 as a second lens layer, and a planarization layer 17. The substrate 11 is made of an inorganic material having optical transparency such as glass or quartz. A surface of the substrate 11 on the liquid crystal layer 40 side is a surface 11a. The substrate 11 has a plurality of recesses 12 formed in the surface 11a. Each recess 12 is provided for each pixel P. As for the cross-sectional shape of the recessed part 12, the center part is a curved surface, for example, and the peripheral part surrounding a center part is an inclined surface (what is called a taper-shaped surface). In addition, the whole recessed part 12 may be comprised by the curved surface.

The lens layer 13 is formed to be thicker than the depth of the recess 12 so as to fill the recess 12 and cover the surface 11 a of the substrate 11. 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 refractive index larger 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, a convex microlens ML1 protruding toward the substrate 11 is formed. That is, the portion of the lens layer 13 that fills the recess 12 is the microlens ML1. Each microlens ML1 is provided corresponding to the pixel P. Further, the micro lens array MLA1 is configured by the plurality of micro lenses ML1. The surface of the lens layer 13 is a flat surface that is substantially parallel to the surface 11 a of the substrate 11.

  Incident light that enters the center of the microlens ML1 is condensed toward the center (the focal point of the curved surface) of the microlens ML1. Further, the incident light incident on the peripheral edge (inclined surface) of the microlens ML1 is refracted toward the center of the microlens ML1 at substantially the same angle if the incident angles are approximately the same. Therefore, compared to the case where the entire microlens ML1 is configured by a curved surface, excessive refraction of incident light is suppressed, and variation in angle of light incident on the liquid crystal layer 40 is suppressed.

  The lens layer 15 is formed on the lens layer 13. The lens layer 15 has, for example, the same refractive index as that of the lens layer 13 and is formed of the same material as that of the lens layer 13. The lens layer 15 has a plurality of convex portions 16 projecting toward the liquid crystal layer 40 (on the side opposite to the microlens ML1). The convex portion 16 in the lens layer 15 is the microlens ML2. Hereinafter, the surface of the convex portion 16 (surface in contact with the planarization layer 17) is referred to as a lens surface.

  Each convex portion 16 is provided corresponding to the pixel P, and is disposed so as to overlap each concave portion 12 in plan view. Therefore, the microlens ML2 is disposed so as to overlap the microlens ML1 in plan view. The cross-sectional shape of the convex portion 16 is similar to the cross-sectional shape of the concave portion 12. Details of the cross-sectional shape of the convex portion 16 will be described later.

  Note that the microlens array substrate 10 according to the present embodiment does not include the optical path length adjustment layer included in the microlens array substrate described in Patent Document 1 between the microlens ML1 and the microlens ML2. The reason why the optical path length adjustment layer can be eliminated in the microlens array substrate 10 will be described later.

The planarizing layer 17 is formed thicker than the height of the convex portions 16 so as to cover the lens layer 15 by filling the spaces between the convex portions 16 and the periphery of the convex portions 16. The planarizing layer 17 is light transmissive, and is made of, for example, an inorganic material having a refractive index lower than that of the lens layer 15. Examples of such an inorganic material include SiO ₂ . By covering the convex portion 16 with the planarizing layer 17, a convex microlens ML2 as a second microlens is configured. Each microlens ML2 is provided corresponding to the pixel P. Further, a microlens array MLA2 is configured by the plurality of microlenses ML2.

  The flattening layer 17 has a function of adjusting the distance from the microlens ML2 to the light shielding layer 26 to a desired value. Therefore, the layer thickness of the planarizing layer 17 is appropriately set based on optical conditions such as the focal length of the microlens ML2 corresponding to the wavelength of light. The surface of the planarization layer 17 is a substantially flat surface.

  The light shielding layer 32 is provided on the microlens array substrate 10 (flattening layer 17). The light shielding layer 32 is provided so as to surround the display area E (see FIG. 1) where the microlens ML1 and the microlens ML2 are arranged. The light shielding layer 32 is formed of, for example, a metal or a metal compound. The light shielding layer 32 may be provided in the display area E so as to overlap the light shielding layer 22 and the light shielding layer 26 of the element substrate 20 in a plan view. In this case, the light shielding layer 32 may be formed in a lattice shape, an island shape, a stripe shape, or the like, but is preferably disposed in a narrower range than the light shielding layer 22 and the light shielding layer 26 in a plan view.

  A protective layer 33 is provided so as to cover the microlens array substrate 10 (planarization layer 17) 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 formed of, for example, a metal or a metal compound. 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 light shielding layer 22 is composed of the light shielding layer 22 and the light shielding layer 26. 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 light is transmitted through the region of the pixel P. Opening T

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 first embodiment, for example, light emitted from a light source or the like is incident from the counter substrate 30 (substrate 11) side including the microlenses ML1 and ML2. Of the incident light, the light L1 incident on the center of the first-stage microlens ML1 along the normal direction of the surface of the counter substrate 30 (substrate 11) travels straight to the center of the second-stage microlens ML2. , Travels straight through, passes through the opening T of the pixel P, and exits toward the element substrate 20.

  In the following, the normal direction of the surface of the counter substrate 30 (substrate 11) is simply referred to as “normal direction”. The “normal direction” is a direction along the Z direction in FIG. 3 and is substantially the same as the normal direction of the element substrate 20 (substrate 21).

  If the light L2 incident on the end portion of the microlens ML1 along the normal direction goes straight as it is, the light L2 is shielded by the light shielding layer 26 as shown by the broken line, but between the substrate 11 and the lens layer 13. Due to the difference in refractive index (positive refractive power), the light is refracted toward the center of the microlens ML1 and enters the microlens ML2. The light L2 incident on the microlens ML2 is further refracted toward the center side of the microlens ML2 due to the difference in refractive index (positive refractive power) between the lens layer 15 and the planarization layer 17, and the pixel P The light passes through the opening T and is emitted to the element substrate 20 side.

  The light L3 incident on the end of the microlens ML1 obliquely with respect to the normal direction and toward the outside with respect to the center of the microlens ML1 goes straight as it is. However, the light is refracted toward the center of the microlens ML1 due to the difference in refractive index between the substrate 11 and the lens layer 13, and enters the microlens ML2. If the light L3 incident on the microlens ML2 goes straight as it is, it is shielded by the light shielding layer 26 as shown by the broken line, but due to the difference in refractive index between the lens layer 15 and the flattening layer 17, the The light is further refracted toward the center of the lens ML2, passes through the opening T of the pixel P, and is emitted toward the element substrate 20 side.

  As described above, in the liquid crystal device 1, the light L2 and L3 that are shielded by the light shielding layer 32 and the light shielding layer 26 when the light travels straight as it is are caused by the action of the two-stage microlenses ML1 and ML2, and the opening T of the pixel P. Can be refracted to the center side of the aperture T and transmitted through the opening T. 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.

<Cross-sectional shape of second microlens>
Next, the cross-sectional shape of the second microlens (microlens ML2) according to the first embodiment will be described with reference to FIG. FIG. 4 is a schematic cross-sectional view showing a cross-sectional shape of the second microlens according to the first embodiment. Specifically, FIG. 4 is a partially enlarged view of the microlens ML2 (convex portion 16) in FIG.

  As shown by a solid line in FIG. 4, the lens surface of the microlens ML2 (convex portion 16) according to the first embodiment has a central portion 16a and a peripheral portion 16b arranged outside the central portion 16a. doing. The curvature of the peripheral portion 16b is smaller than the curvature of the central portion 16a. At least the end portion side of the peripheral portion 16b is a tapered inclined surface.

  In FIG. 4, as a comparison of the cross-sectional shape of the convex portion 16, an ellipse 19 is shown by a two-dot chain line. For example, like the microlens array substrate described in Patent Literature 1, the cross-sectional shape of the second microlens provided in the conventional microlens array substrate is often a semi-elliptical shape. Therefore, FIG. 4 is a diagram showing the cross-sectional shape of the microlens ML2 (convex portion 16) according to the first embodiment in comparison with the cross-sectional shape of the conventional second microlens (microlens ML2e). In FIG. 4, the X axis is an axis passing through the center 19c of the ellipse 19 along the X direction, and the Z axis is an axis passing through the center 19c of the ellipse 19 along the Z direction.

  The length of the major axis (major axis) 19d of the ellipse 19 shown in FIG. 4 is the same as the diameter of the convex portion 16 (length in the X-axis direction), and is 1 of the minor axis (minor axis) 19e of the ellipse 19. The length of / 2 is assumed to be the same as the height of the convex portion 16 (length in the Z-axis direction). Therefore, the cross-sectional shape of the microlens ML2 according to the present embodiment substantially overlaps the lower half (−Z direction side) of the ellipse 19 that is the cross-sectional shape of the conventional microlens ML2e. However, the lens surface of the microlens ML2 has a shape close to a triangle in which the peripheral portion 16b is recessed inward from the lens surface of the conventional microlens ML2e (elliptical shape 19).

  Each part of the lens surface of the micro lens ML2 (convex part 16) is compared with each part of the lens surface of the conventional micro lens ML2e (ellipse 19). The curvature of the peripheral portion 16b of the microlens ML2 is smaller than the curvature of the peripheral portion 19b of the microlens ML2e. Therefore, the angle formed by the lens surface and the surface 11a of the substrate 11 in the peripheral portion 16b of the microlens ML2 is smaller than that in the peripheral portion 19b of the conventional microlens ML2e.

  Therefore, the incident angle with respect to the lens surface of the light incident on the peripheral portion 16b of the microlens ML2 along the normal direction (Z-axis direction) from the + Z direction side is the light incident on the peripheral portion 19b of the conventional microlens ML2e. It becomes smaller than the incident angle. Accordingly, since the refraction angle of light emitted from the peripheral portion 16b of the microlens ML2 is smaller than that of the conventional microlens ML2e, the tilt angle with respect to the normal direction (hereinafter simply referred to as the tilt angle) is also small.

  Further, in the conventional microlens ML2e, the curvature of the peripheral portion 19b is larger than the curvature of the central portion 19a, and the angle formed by the lens surface and the surface 11a of the substrate 11 in the peripheral portion 19b becomes larger toward the end portion. Therefore, as the incident position of light incident on the peripheral portion 19b from the normal direction is closer to the end portion, the incident angle becomes larger and the refraction angle becomes larger. Therefore, the light emitted from the peripheral portion 19b of the conventional microlens ML2e includes a lot of light having a large inclination angle and a large variation.

  As a result, in the conventional microlens array substrate, depending on the position and range of light incident from the first microlens to the second microlens (microlens ML2e), that is, on the peripheral portion 19b of the second microlens. Depending on whether the amount of incident light is large or small, a large difference occurs in the distribution range of the tilt angle of the emitted light.

  On the other hand, among the lens surfaces of the microlens ML2 according to this embodiment, the end portion side of the peripheral portion 16b is a tapered inclined surface. In the tapered inclined surface, the angle formed by the lens surface and the surface 11a of the substrate 11 is almost the same at any position. Therefore, the incident angle of light incident on the peripheral portion 16b of the microlens ML2 from the normal direction is substantially the same regardless of the incident position. For this reason, the light emitted from the peripheral portion 16b of the microlens ML2 has substantially the same refraction angle, and thus becomes light with a small variation in inclination angle.

  As a result, in the microlens array substrate 10 according to the present embodiment, even though the position and range of light incident on the microlens ML2 from the microlens ML1 are different from those of the conventional microlens array substrate (in the peripheral portion 16b). Regardless of whether the incident light is large or small, the distribution range of the tilt angle of the emitted light can be kept small. Thereby, the brightness and contrast ratio of the liquid crystal device 1 can be improved.

  Furthermore, in the conventional microlens ML2e, the angle formed by the lens surface and the surface 11a of the substrate 11 is close to a right angle at the end of the peripheral portion 19b, so that light incident on the end of the peripheral portion 19b is reflected by the lens surface. In some cases, the amount of reflected light increases, and the incident angle is greater than the critical angle, resulting in total reflection. A part of such reflected light becomes stray light in the liquid crystal device and causes a light leakage current of the TFT 24. When the light leakage current of the TFT 24 is generated, flicker or unevenness occurs in the display image and the display quality is deteriorated.

  In the microlens ML2 according to this embodiment, since the end portion side of the peripheral portion 16b is a tapered inclined surface, the angle formed between the lens surface and the surface 11a of the substrate 11 is smaller than that of the conventional microlens ML2e. Become. Therefore, even if light enters the end of the microlens ML2, reflected light that is reflected by the lens surface is less likely to occur. As a result, in the microlens array substrate 10 according to the present embodiment, stray light generated by reflected light can be reduced. Therefore, a display quality that causes light leakage current of the TFT 24 due to stray light and causes a flicker or unevenness in a display image. Can be suppressed.

  Further, in the conventional microlens array substrate, since the angle formed by the lens surface and the surface 11a of the substrate 11 is close to a right angle at the end, a steep valley-like depression (step) is formed between the adjacent microlenses ML2e. ) Is configured. Therefore, a groove (void) is formed in this portion of the planarization layer 17 (see FIG. 3) formed on the lens layer 15 including the microlens ML2e. If such a groove is present in the planarizing layer 17, incident light may be irregularly reflected to cause stray light, and the pixel electrode 28 formed in the upper layer may be disconnected.

  In the microlens ML2 according to the present embodiment, since the end portion is tapered, the angle formed by the lens surface and the surface 11a of the substrate 11 at the end portion is smaller than that of the microlens ML2e. The indentation (step) between them becomes gentle. Therefore, in the microlens array substrate 10 according to the present embodiment, the step coverage of the planarizing layer 17 formed on the lens layer 15 is good, and the grooves are hardly formed. Thereby, generation | occurrence | production of a stray light and a disconnection can be suppressed.

  Note that the cross-sectional shape of the microlens ML2 is preferably substantially symmetric with respect to the apex of the convex portion 16. 4 shows an example in which the cross-sectional shape of the convex portion 16 is symmetric in the X-axis direction, it is preferable that the convex shape 16 is also symmetric in the Y-axis direction (see FIG. 1). Further, the cross-sectional shape of the convex portion 16 may be symmetrical over 360 ° with respect to the apex of the convex portion 16 in plan view.

  When the cross-sectional shape of the microlens ML2 is substantially symmetric with respect to the apex of the convex portion 16, the light incident on the position symmetrical to the apex of the convex portion 16 out of the light incident on the microlens ML2 is approximately Refract at the same angle. Thereby, the dispersion | variation in the angle of the light inject | emitted from microlens ML2 becomes small. As a result, variations in brightness and contrast ratio can be suppressed, and brightness within the opening T of the pixel P can be made more uniform.

  Next, the influence when the distance between the microlens ML1 and the microlens ML2 varies in the microlens array substrate 10 will be described in comparison with a conventional microlens array substrate. FIG. 5 is a schematic cross-sectional view showing an enlarged main part of two pixels in FIG. FIG. 29 is an enlarged schematic cross-sectional view showing the main part of two pixels in a conventional microlens array substrate.

  Although the manufacturing method of the microlens array substrate will be described later, the film thickness when the lens layer 13 (lens material layer 13a) and the lens layer 15 (first lens material layer 15a and second lens material layer 15b) are formed. And the distance between the microlens ML1 and the microlens ML2 may vary due to variations in the amount of polishing and variations in the polishing amount when the surface of the lens layer 13 (lens material layer 13a) is planarized.

  FIG. 29 shows a microlens array substrate 50 provided with the above-described microlens ML2e (ellipse 19) as a second microlens as an example of a conventional microlens array substrate. The microlens array substrate 50 includes the microlens ML1 of the microlens array substrate 10 according to the present embodiment in the first microlens.

  FIG. 29 also shows a case where the distance between the microlens ML1 and the microlens ML2e is different between the pixel P1 and the pixel P2. In the pixel P1, the distance between the microlens ML1 and the microlens ML2e is D1. In the pixel P2, the distance between the microlens ML1 and the microlens ML2e is D2 (D2 <D1). In practice, the distance between the microlens ML1 and the microlens ML2e is not greatly different between adjacent pixels P in the same microlens array substrate 50 as shown in FIG.

  In the pixel P1 and the pixel P2, the light L4 is light that is incident on the microlens ML1 along the normal direction and is refracted and condensed toward the center of the microlens ML1. The light L5 is light that is incident on a position symmetrical to the position where the light L4 is incident on the center of the microlens ML1 and is refracted and condensed toward the center of the microlens ML1. The inclination angles of the light L4 and the light L5 are the same.

  The light L4 and the light L5 emitted from the microlens ML1 travel toward the center of the microlens ML1 as the distance from the microlens ML1 increases. That is, the range of the light condensed by the microlens ML1 (including the light inside the light L4 and the light L5) becomes smaller as the distance from the microlens ML1 increases.

  In the pixel P1, the light L4 and L5 emitted from the microlens ML1 is incident on the peripheral portion 19b of the microlens ML2e, is condensed on the center side of the microlens ML2e, and enters the opening T of the pixel P1. The inclination angles of the light L4 and L5 emitted from the microlens ML2e are larger than those when emitted from the microlens ML1.

  In the pixel P2, since the distance D2 between the microlens ML1 and the microlens ML2e is smaller than the distance D1 in the pixel P1, the light condensed by the microlens ML1 (inside the light L4 and the light L5) compared to the pixel P1. The range in which the light is incident on the lens surface of the microlens ML2e is widened. Therefore, the light L4 and L5 emitted from the microlens ML1 is incident near the end portion of the peripheral portion 19b of the microlens ML2e.

  As described above, the angle formed by the lens surface of the microlens ML2e and the surface 11a (see FIG. 3) of the substrate 11 increases toward the end of the peripheral portion 19b, so that the pixel P2 exits from the microlens ML2e. The inclination angles of the light L4 and L5 to be emitted are larger than those of the pixel P1. When the light collected by the microlens ML1 enters the wide range of the microlens ML2e as in the pixel P2, more light enters the peripheral portion 19b than when the light enters the narrow range. The light emitted from the lens ML2e includes a lot of light having a large inclination angle and a large variation in inclination angle.

  As a result, in the pixel P2, compared to the pixel P1, the brightness and the contrast ratio are easily reduced. In addition, when a liquid crystal device including a conventional microlens array substrate 50 is used in an electronic device such as a projector that projects image light onto a screen or the like, if a large amount of light with a large tilt angle is included, the projection lens kicks it. The amount of light (light that is not used) increases, and the brightness of an image projected on a screen or the like decreases.

  Even if the distance between the microlens ML1 and the microlens ML2e is the same, if the planar positional relationship between the microlens ML1 and the microlens ML2e is shifted, the light collected by the microlens ML1 is microscopic. The position incident on the lens ML2e changes.

  For example, in the pixel P1, when the positions of the light L4 and L5 incident on the microlens ML2e are shifted to the + X direction side or the −X direction side, either the light L4 or L5 is incident closer to the end of the peripheral portion 19b. It becomes. Therefore, even when the planar positional relationship between the microlens ML1 and the microlens ML2e varies, the light emitted from the microlens ML2e includes a lot of light having a large tilt angle and a large variation in tilt angle. Will be.

  Thus, in the conventional microlens array substrate 50, when the distance between the microlens ML1 and the microlens ML2e varies, or when the planar positional relationship between the microlens ML1 and the microlens ML2e varies. A large difference occurs in the distribution range of the tilt angle of the emitted light. Further, when the amount of light incident near the end of the microlens ML2e increases, stray light due to reflected light tends to occur. As a result, there is a problem that display quality is deteriorated or unstable in an electro-optical device or an electronic apparatus including the microlens array substrate 50.

  Also in the pixel P1 and the pixel P2 shown in FIG. 5, it is assumed that the lights L4 and L5 are emitted from the microlens ML1 at the same inclination angle as the pixel P1 and the pixel P2 shown in FIG. In the microlens array substrate 10 according to the present embodiment shown in FIG. 5, in the pixel P1, the light L4 and L5 emitted from the microlens ML1 is incident on the peripheral portion 16b of the microlens ML2, and the center side of the microlens ML2 And enters the opening T of the pixel P1.

  In the pixel P2, the lights L4 and L5 emitted from the microlens ML1 are incident closer to the end of the peripheral portion 16b of the microlens ML2 than the pixel P1, and are condensed toward the center of the microlens ML2. In the opening T. Comparing the pixel P1 and the pixel P2, the light L4 and L5 are incident on the tapered inclined surface at the same incident angle at the same incident angle, although the incident positions at the peripheral portion 16b are different. It is injected. Therefore, as compared with the conventional microlens array substrate 50, the inclination angle of the light emitted from the microlens ML2 is reduced, and the variation in the inclination angle is also reduced.

  Therefore, in the microlens array substrate 10 according to the present embodiment, even when the distance between the microlens ML1 and the microlens ML2e varies, or when the planar positional relationship between the microlens ML1 and the microlens ML2e varies. The distribution range of the tilt angle of the emitted light can be kept small. Thereby, compared with the conventional microlens array substrate 50, the fall of brightness and the fall of contrast ratio are suppressed.

  In the microlens array substrate 10, the inclination angle of the emitted light is smaller than that of the conventional microlens array substrate 50. Therefore, the light that is kicked by the projection lens when used in an electronic device such as a projector. Since (unused light) is reduced, a reduction in image brightness can be suppressed. Further, since the reflected light hardly occurs even when the amount of light incident near the end of the microlens ML2 increases, stray light caused by the reflected light can be suppressed.

  As a result, the microlens array substrate 10 according to the present embodiment can improve and stabilize the display quality in electro-optical devices and electronic devices as compared to the conventional microlens array substrate 50.

<Manufacturing method of microlens array substrate>
Next, a method for manufacturing the microlens array substrate 10 according to the first embodiment will be described. 6 to 15 are schematic cross-sectional views illustrating the method for manufacturing the microlens array substrate according to the first embodiment. Specifically, each of FIGS. 6 to 15 corresponds to a schematic cross-sectional view along the line AA ′ in FIG. 3, and the vertical direction (Z direction) is reversed from FIG. 3.

First, as shown in FIG. 6, a control film 70 made of an oxide film such as SiO ₂ is formed on the surface 11 a of the light-transmitting substrate 11 made of quartz or the like. The control film 70 has an etching rate in isotropic etching different from that of the substrate 11, and has a width direction (the X direction and the X direction shown in FIG. 3) with respect to 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, a mask layer 72 is formed on the control film 70. Then, the mask layer 72 is patterned to form openings 72 a in the mask layer 72. The position of the planar center of the opening 72a is the center of the recess 12 to be formed. Subsequently, isotropic etching is performed on the substrate 11 covered with the control film 70 through the opening 72 a of the mask layer 72. Although not shown, by this isotropic etching, an opening is formed in a region overlapping the opening 72a of the control film 70, and the substrate 11 is etched through the opening.

  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. As a result, 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, so that the substrate is expanded along with the enlargement of the opening formed in the control film 70. The etching amount in the width direction 11 is larger than the etching amount in the depth direction.

  The control film 70 and the substrate 11 are etched from the opening 72a by isotropic etching, and a recess 12 is formed on the surface 11a side of the substrate 11 as shown in FIG. By setting the etching rate as described above, the width direction of the recess 12 is expanded more than the depth direction, and a tapered slope is formed at the peripheral edge of the recess 12. Note that the control film 70 may not be provided in the case where the concave portion 12 that is entirely configured by a curved surface is formed. FIG. 7 shows a state after the mask layer 72 and the control film 70 are removed.

  In this step, adjacent recesses 12 in the X direction and Y direction in which the pixels P are arranged are connected to each other, and adjacent recesses 12 in the diagonal direction of the pixels P (hereinafter simply referred to as diagonal directions) are connected to each other. It is preferable to finish the isotropic etching in a state of being separated, that is, in a state where the surface 11a of the substrate 11 is left between the recesses 12 adjacent in the diagonal direction.

  If isotropic etching is performed until the recesses 12 adjacent to each other in the diagonal direction are connected to each other, the mask layer 72 may be lifted off from the substrate 11 and peeled off. If the isotropic etching is completed with the surface 11a of the substrate 11 remaining between the adjacent recesses 12, the mask layer 72 can be more reliably supported until the isotropic etching is completed.

  Next, as shown in FIG. 8, a lens material layer is deposited by depositing an inorganic material that is light transmissive and has a refractive index larger than that of the substrate 11 so as to cover the surface 11 a side of the substrate 11 and fill the recess 12. 13a is formed. The lens material layer 13a can be formed using, for example, a CVD method. Since the concave portion 12 is formed so as to be embedded, the surface of the lens material layer 13 a has an uneven shape reflecting the unevenness caused by the concave portion 12 of the substrate 11. The lens material layer 13a may be formed by a single film formation or a plurality of film formations.

  Next, as shown in FIG. 9, the lens material layer 13a is flattened. In the flattening process, for example, by using a CMP (Chemical Mechanical Polishing) process or the like, the upper surface of the lens material layer 13a is polished and removed, whereby the upper surface is flattened and the lens layer 13 is removed. Is formed. And the microlens ML1 is comprised by embedding the material of the lens layer 13 in the recessed part 12. FIG. In the present embodiment, the planarization process is finished with the lens layer 13 remaining on the surface 11 a of the substrate 11.

  Next, as shown in FIG. 10, an inorganic material having optical transparency and a refractive index larger than that of the substrate 11 is deposited so as to cover the lens layer 13 to form the first lens material layer 15 a. . The first lens material layer 15a can be formed using, for example, a CVD method.

  In the conventional microlens array substrate, an optical path length adjustment layer is formed between the lens layer 13 and the upper lens layer 15. However, in the microlens array substrate 10 according to the present embodiment, the optical path length adjustment layer is provided. Do not form. Therefore, compared with the conventional microlens array substrate, the process of forming the optical path length adjusting layer is not required, and therefore the manufacturing lead time of the microlens array substrate 10 can be shortened and the production cost can be reduced. In addition, since the optical path length adjustment layer is not formed, it is possible to eliminate the influence of the variation in the film thickness of the optical path length adjustment layer that contributes to the variation in the distance between the microlens ML1 and the microlens ML2.

  Subsequently, as shown in FIG. 10, a resist layer 73 is formed on the first lens material layer 15a. The resist layer 73 is formed of, for example, a positive photosensitive resist in which an exposed portion is removed by development. The resist layer 73 can be formed by, for example, a spin coat method or a roll coat method.

  Next, although not shown, the resist layer 73 is exposed and developed through a mask provided with a light shielding portion corresponding to the position of the recess 12. As a result, as shown in FIG. 11, a portion of the resist layer 73 other than the region overlapping the light shielding portion of the mask is exposed and removed, and a portion corresponding to a position where the convex portion 16 is formed in a later step. 73a remains. Therefore, the remaining portions 73a are separated from each other in the X direction, the Y direction, and the diagonal direction. The planar shape of the portion 73a is, for example, a substantially rectangular shape, but the corners at the four corners may be rounded.

  In the process described later, the microlens ML2 (convex portion 16) is formed in a portion overlapping the portion 73a in the first lens material layer 15a. In the microlens array substrate 10 according to the present embodiment, an optical path length adjustment layer is not formed, and the distance between the microlens ML1 and the microlens ML2 can be reduced as compared with the conventional microlens array substrate. Thereby, since the displacement of the mask when the resist layer 73 is exposed is suppressed, the displacement between the microlens ML1 and the microlens ML2 can be suppressed.

  Next, the remaining portion 73a of the resist layer 73 is softened (melted) by performing a heat treatment such as a reflow treatment. The melted portion 73a is in a fluid state, and the surface is deformed into a curved surface by the action of surface tension. As a result, as shown in FIG. 12, a curved convex portion 73b is formed from the portion 73a remaining on the first lens material layer 15a. The bottom side (first lens material layer 15a side) of the convex part 73b is substantially rectangular in plan view, but the tip side (upper side) of the convex part 73b is substantially concentric in plan view. The

  Next, as shown in FIG. 13, anisotropic etching such as dry etching is performed on the convex portion 73b and the first lens material layer 15a from above. Thereby, the convex portion 73b made of resist is gradually removed, and the exposed portion of the first lens material layer 15a is etched along with the removal of the convex portion 73b. As a result, the shape of the convex portion 73b is reflected on the surface side of the first lens material layer 15a. In this step, the anisotropic etching is finished in a state where the first lens material layer 15a is left on the lens layer 13 (the surface of the lens layer 13 is not exposed).

  Next, as shown in FIG. 14, an inorganic material having a refractive index larger than that of the substrate 11 is deposited so as to cover the first lens material layer 15a by using, for example, a CVD method, and the second lens material is then deposited. Layer 15b is formed. By laminating the second lens material layer 15b on the first lens material layer 15a, the lens layer 15 having the convex portion 16 in which the shape of the convex portion 73b is enlarged is formed. The refractive index of the second lens material layer 15b may be the same as the refractive index of the first lens material layer 15a, or may be larger than the refractive index of the first lens material layer 15a. The second lens material layer 15b may be formed by a single film formation or a plurality of film formations.

  Next, as shown in FIG. 15, a planarizing layer 17 is formed by depositing an inorganic material having light transmittance and having a refractive index comparable to that of the substrate 11, for example, so as to cover the lens layer 15. Then, the flattening layer 17 is subjected to a flattening process, and the uneven shape in which the convex portions 16 of the lens layer 15 are reflected on the surface of the flattening layer 17 is polished and removed. The microlens ML <b> 2 is configured by covering the convex portion 16 with the planarizing layer 17. As described above, the microlens array substrate 10 is completed.

  In this step, as described above, since the end portion side of the convex portion 16 (microlens ML2) is a tapered inclined surface, the surface of the planarizing layer 17 is compared with the conventional microlens array substrate 50. The concavo-convex shape becomes gentle. Therefore, the amount of the planarization process (CMP process) can be reduced. These contribute to shortening the manufacturing lead time and production cost of the microlens array substrate 10.

  Note that the cross-sectional shape of the convex portion 16 shown in FIG. 4 is the same as that of the convex portion 73b of the first lens material layer 15a by forming the second lens material layer 15b on the first lens material layer 15a. The shape reflecting the shape is enlarged and formed (see FIG. 14). Therefore, the cross-sectional shape (see FIG. 12) of the convex portion 73b formed from the resist layer 73 is the cross-sectional shape after the anisotropic etching is performed on the first lens material layer 15a (see FIG. 13), It is set as appropriate based on the cross-sectional shape (see FIG. 14) after the second lens material layer 15b is formed.

  The cross-sectional shape of the convex portion 73b can be adjusted by processing conditions when the remaining portion 73a of the resist layer 73 is subjected to heat treatment. Further, instead of the heat treatment, the resist layer 73 shown in FIG. 10 is projected from the resist layer 73 using, for example, a method of exposing using a gray scale mask or an area gradation mask, a method of performing multi-step exposure, and the like. You may make it process in the shape of the part 73b. Then, the etching conditions in the step shown in FIG. 13 are such that the etching rate of the material (resist) of the convex portion 73b and the etching rate of the material of the first lens material layer 15a can be made substantially the same. The shape of the convex portion 73b may be transferred to one lens material layer 15a.

  After the microlens array substrate 10 is completed, 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 to face each other using a known technique. A substrate 30 is obtained. Further, a known method is sequentially applied to the light shielding layer 22, the insulating layer 23, the TFT 24, the insulating layer 25, the light shielding layer 26, the insulating layer 27, the pixel electrode 28, and the alignment film 29 on the substrate 21. The element substrate 20 is obtained by forming using them.

  Subsequently, the element substrate 20 and the counter substrate 30 are positioned, and a thermosetting or photocurable adhesive is disposed between the element substrate 20 and the counter substrate 30 as a sealing material 42 (see FIG. 1) and cured. Let them stick together. The liquid crystal device 1 is completed by enclosing and sandwiching liquid crystal in a space formed by the element substrate 20, the counter substrate 30, and the sealing material 42. Before the element substrate 20 and the counter substrate 30 are bonded together, the liquid crystal may be disposed in a region surrounded by the sealant 42.

<Electronic equipment>
Next, an electronic apparatus according to the first embodiment will be described with reference to FIG. FIG. 16 is a schematic diagram illustrating a configuration of a projector as the electronic apparatus according to the first embodiment.

  As shown in FIG. 16, a projector (projection display device) 100 as an electronic apparatus according to the first embodiment includes a polarization illumination device 110, two dichroic mirrors 104 and 105, and three reflection mirrors 106 and 107. , 108, 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 enters the liquid crystal light valve 123 via a light guide system including 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 formed 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 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. The liquid crystal light valves 121, 122, and 123 are those to which the liquid crystal device 1 is applied.

  According to the configuration of the projector 100 according to the first embodiment, the liquid crystal light valve 121, 122, 123 includes the liquid crystal device 1 with good brightness and contrast ratio and less kicking by the projection lens 117. The projector 100 having display and excellent display quality can be provided.

(Second Embodiment)
In the second embodiment, the manufacturing method of the microlens array substrate is different from that of the first embodiment, and the configuration of the second microlens is accordingly different, but the basic configuration of the liquid crystal device is the same. Here, a manufacturing method of the microlens array substrate according to the second embodiment will be described with reference to FIGS.

<Manufacturing method of microlens array substrate>
17 to 21 are schematic cross-sectional views illustrating a method for manufacturing a microlens array substrate according to the second embodiment. The steps shown in FIGS. 17 to 21 correspond to the steps shown in FIGS. 11 to 15 of the first embodiment. Here, differences from the first embodiment will be described, and the same components as those in the first embodiment will be denoted by the same reference numerals and description thereof will be omitted.

  The second embodiment is different from the first embodiment in that the first lens material layer 15a formed on the lens layer 13 is formed thinner than the first embodiment. FIG. 17 shows a state in which the resist layer 73 is exposed and a portion 73a corresponding to a position where the convex portion 16 is formed in a later process remains. As shown in FIG. 17, in the second embodiment, the first lens material layer 15a is formed thinner than the thickness of the resist layer 73 formed thereon, for example.

  Next, as shown in FIG. 18, similarly to the first embodiment, the remaining portion 73 a of the resist layer 73 is subjected to a heat treatment such as a reflow treatment so that the first lens material layer 15 a is formed. A curved convex portion 73b is formed.

  Next, as shown in FIG. 19, anisotropic etching is performed on the convex portion 73b and the first lens material layer 15a from above. The anisotropic etching is performed until the convex portion 73b (resist layer 73) is removed. Then, since the thickness of the first lens material layer 15a is thinner than the thickness of the resist layer 73, portions other than the portion overlapping the convex portion 73b in the first lens material layer 15a are removed, and the lower lens layer 13 is removed. The surface of is also etched.

  As a result, the shape of the convex portion 73b is reflected in the lens layer 13 and the remaining portion of the first lens material layer 15a. In this step, the anisotropic etching is finished with the lens layer 13 left on the substrate 11. Further, when the anisotropic etching is finished, the planarized surface of the lens layer 13 remains.

  Next, as shown in FIG. 20, an inorganic material having a refractive index larger than that of the substrate 11 is deposited so as to cover the lens layer 13 and the first lens material layer 15a by using, for example, a CVD method. A second lens material layer 15b is formed. The refractive index of the second lens material layer 15b may be the same as the refractive index of the first lens material layer 15a, or may be larger than the refractive index of the first lens material layer 15a. The second lens material layer 15b may be formed by a single film formation or a plurality of film formations. The first lens material layer 15a and the second lens material layer 15b constitute the lens layer 15. The thickness of the lens layer 15 is smaller than that of the first embodiment.

  Next, as shown in FIG. 21, the planarization layer 17 is formed so as to cover the lens layer 15 as in the first embodiment. Then, a planarization process is performed on the planarization layer 17. Thus, the microlens array substrate 10A according to the second embodiment is completed.

  In the microlens array substrate 10A according to the second embodiment, the lens layer 13 constituting the microlens ML1 is flattened in the cross-sectional shape of the microlens ML2 (convex portion 16) indicated by a broken line in FIG. The difference from the first embodiment is that the surface is included. In other words, the microlens ML <b> 2 (convex portion 16) is configured by a part (surface side) of the lens layer 13 and the lens layer 15.

  According to the configuration of the microlens array substrate 10A according to the second embodiment, the thickness of the lens layer 15 constituting the microlens ML2 (convex portion 16) can be reduced compared to the first embodiment.

(Third embodiment)
In the third embodiment, the manufacturing method of the microlens array substrate is different from that of the first embodiment, and the configuration of the second microlens is accordingly different, but the basic configuration of the liquid crystal device is the same. Here, a manufacturing method of the microlens array substrate according to the third embodiment will be described with reference to FIGS.

<Manufacturing method of microlens array substrate>
22 to 26 are schematic cross-sectional views illustrating a method for manufacturing a microlens array substrate according to the third embodiment. The processes shown in FIGS. 22 to 26 correspond to the processes shown in FIGS. 11 to 15 of the first embodiment. Here, differences from the first embodiment will be described, and the same components as those in the first embodiment will be denoted by the same reference numerals and description thereof will be omitted.

  The third embodiment differs from the first embodiment in that the lens layer 13 formed on the substrate 11 is formed thick and the first lens material layer 15a is not formed. FIG. 22 shows a state in which the resist layer 73 is exposed and a portion 73a corresponding to a position where the convex portion 16 is formed in a later process remains. As shown in FIG. 22, the lens layer 13 is formed thicker than in the first embodiment. Further, the first lens material layer 15 a is not formed on the lens layer 13.

  Next, as shown in FIG. 23, similarly to the first embodiment, the remaining portion 73a of the resist layer 73 is subjected to a heat treatment such as a reflow treatment, whereby a curved convex shape is formed on the lens layer 13. A shaped portion 73b is formed.

  Next, as shown in FIG. 24, anisotropic etching is performed on the convex portion 73b and the lens layer 13 from above. In this step, anisotropic etching is performed until the planarized surface of the lens layer 13 does not remain. As a result, the shape of the convex portion 73 b is reflected on the surface side of the lens layer 13.

  Next, as shown in FIG. 25, the second lens material layer 15b is formed by depositing an inorganic material having a refractive index larger than that of the substrate 11 so as to cover the lens layer 13 by using, for example, a CVD method. To do. The second lens material layer 15b may be formed by a single film formation or a plurality of film formations. In the third embodiment, the lens layer 15 is configured by the second lens material layer 15b.

  Next, as shown in FIG. 26, the planarization layer 17 is formed so as to cover the lens layer 15 as in the first embodiment. Then, a planarization process is performed on the planarization layer 17. Thus, the microlens array substrate 10B according to the third embodiment is completed.

  In the microlens array substrate 10B according to the third embodiment, the lens layer 13 constituting the microlens ML1 is included in the cross-sectional shape of the microlens ML2 (convex portion 16) indicated by a broken line in FIG. The difference from the first embodiment is that the surface of the lens layer 13 that has been flattened is not left. According to the configuration of the microlens array substrate 10B according to the third embodiment, the step of forming the first lens material layer 15a is not necessary as compared with the first embodiment and the second embodiment. Production lead time can be shortened and production costs can be reduced.

(Fourth embodiment)
<Electro-optical device>
In the fourth embodiment, a CMOS (Complementary Metal Oxide Semiconductor) type imaging device will be described as an example of an electro-optical device. This imaging device can be suitably used as an imaging device for a video camera, which will be described later, for example. The electro-optical device may be a CCD (Charge Coupled Device) type imaging device.

  FIG. 27 is a schematic cross-sectional view illustrating a configuration of an imaging apparatus according to the fourth embodiment. Constituent elements common to the first embodiment are denoted by the same reference numerals and description thereof is omitted. As shown in FIG. 27, the imaging device 6 according to the fourth embodiment includes a light receiving element substrate 60 as a first substrate and a microlens array substrate 10 (10A, 10B) as a second substrate. ing. In the imaging device 6, the microlens array substrate 10 itself corresponds to the second substrate.

  Although a plan view is omitted, the pixels P have a substantially polygonal (for example, substantially rectangular) planar shape and are arranged in a matrix. Each of the plurality of pixels P is provided with a light receiving element 63 and a pixel transistor (not shown) (so-called CMOS transistor). In each of the plurality of pixels P, a microlens ML1 and a microlens ML2 provided on the microlens array substrate 10 are arranged so as to overlap the light receiving element 63 in plan view.

  The light receiving element substrate 60 includes a substrate 61, a semiconductor layer 62, a light receiving element 63, an interlayer insulating layer 64, a light shielding layer 65, and a planarizing layer 66. The substrate 61 is a semiconductor substrate made of, for example, silicon. A semiconductor layer 62 is provided on the substrate 61, and a light receiving element 63 composed of a photodiode or the like is provided on the semiconductor layer 62.

  The light receiving element 63 is configured by a photoelectric conversion element such as a photodiode. The light receiving element 63 has a light receiving surface 63a. The light receiving element 63 generates signal charges corresponding to the light amount (intensity) of light incident on the light receiving surface 63a by photoelectric conversion, and accumulates the generated signal charges. The pixel transistor is composed of a plurality of transistors such as a transfer transistor, a reset transistor, and an amplification transistor, for example.

The interlayer insulating layer 64 is provided so as to cover the semiconductor layer 62 and the light receiving element 63. The interlayer insulating layer 64 is made of an inorganic material such as SiO ₂ .

  The light shielding layer 65 is provided on the interlayer insulating layer 64 in a lattice shape in plan view. The light shielding layer 65 is formed of, for example, a metal or a metal compound. The light-shielding portion S is configured by the light-shielding layer 65, and a region surrounded by the light-shielding layer 65 (inside the opening 65 a) is an opening T through which light is transmitted in the pixel P region. By providing the light shielding layer 65, it is possible to suppress the light transmitted through the microlens ML1 and the microlens ML2 from entering the light receiving element 63 of the adjacent pixel P.

The planarizing layer 66 is provided so as to cover the interlayer insulating layer 64 and the light shielding layer 65, and has a substantially flat surface. The planarization layer 66 may be formed of an inorganic material such as SiO ₂ or may be formed of a resin material such as acrylic. The microlens array substrate 10 is disposed so as to face the planarizing layer 66 side of the light receiving element substrate 60.

  The imaging device 6 according to the fourth embodiment includes a microlens array substrate 10 that collects incident light. Therefore, in the imaging device 6, not only the light L1 incident on the center of the microlens ML1 along the normal direction but also the light L2 incident on the end of the microlens ML1 along the normal direction or the light incident obliquely. L3 can also be refracted toward the center of the opening T of the pixel P and transmitted through the opening T.

  In addition, the microlens array substrate 10 is provided with less variation in brightness and contrast ratio than in the past. Therefore, the amount of light incident on the light receiving element 63 can be increased as compared with the conventional microlens array substrate 50, so that the light receiving sensitivity can be improved. Further, since stray light generated by the reflected light is reduced, noise due to stray light is reduced in the signal charge generated by the light receiving element 63, so that the S / N ratio and gradation resolution can be improved. it can.

<Electronic equipment>
Next, an electronic apparatus according to the fourth embodiment will be described with reference to FIG. FIG. 28 is a schematic diagram illustrating a configuration of a video camera as an electronic apparatus according to the fourth embodiment. The video camera 200 according to the fourth embodiment is an electronic device that can capture still images and moving images.

  As shown in FIG. 28, a video camera 200 as an electronic apparatus according to the fourth embodiment includes an optical unit 201, a shutter unit 202, an imaging unit 203, a drive unit 204, a signal processing unit 205, and a monitor. 206 and a memory 207. The imaging unit 203 is one to which the imaging device 6 according to the present embodiment is applied. The monitor 206 is one to which the liquid crystal device 1 according to the first embodiment is applied.

  The optical unit 201 includes one or more lenses, guides light (incident light) from the subject to the imaging unit 203, and forms an image on the light receiving surface 63a (see FIG. 27) of the light receiving element 63 of the imaging unit 203. Let The shutter unit 202 is disposed between the optical unit 201 and the imaging unit 203, and controls the light irradiation period and the light shielding period to the imaging unit 203 based on the control of the driving unit 204.

  The imaging unit 203 accumulates signal charges for a certain period according to the light imaged on the light receiving surface 63a via the optical unit 201 and the shutter unit 202. The signal charge accumulated in the imaging unit 203 is transferred according to a drive signal (timing signal) supplied from the drive unit 204. Note that the imaging unit 203 may be included as part of a module configured with the optical unit 201 or the signal processing unit 205.

  The driving unit 204 drives the imaging unit 203 and the shutter unit 202 by outputting a driving signal for controlling the transfer operation of the imaging unit 203 and the shutter operation of the shutter unit 202. The signal processing unit 205 performs various types of signal processing on the signal charges output from the imaging unit 203. An image (image data) obtained by performing signal processing by the signal processing unit 205 is supplied to the monitor 206 for display, supplied to the memory 207, and stored (recorded).

  According to the configuration of the video camera 200 according to the fourth embodiment, since the imaging device 6 is provided with improved light receiving sensitivity and improved S / N ratio and gradation resolution, it is bright and excellent in resolution. A video camera 200 capable of capturing an image can be provided. Since the signal processing in the signal processing unit 205 can be further simplified by improving the S / N ratio and the gradation resolution, the signal processing speed can be increased and the cost can be reduced. Further, since the liquid crystal device 1 capable of obtaining a bright display and an excellent display quality is provided, the video camera 200 capable of displaying an image with a bright and excellent display quality on the monitor 206 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)
In the microlens array substrate 10 according to the first embodiment, the optical path length adjustment layer is not provided between the lens layer 13 and the lens layer 15, but the present invention is limited to such a form. Alternatively, an optical path length adjusting layer may be provided between the lens layer 13 and the lens layer 15. Even in the configuration in which the optical path length adjusting layer is formed between the lens layer 13 and the lens layer 15, when the distance between the microlens ML1 and the microlens ML2 varies as compared with the conventional microlens array substrate, When the planar positional relationship between ML1 and microlens ML2 varies, a decrease in brightness and a decrease in contrast ratio can be suppressed.

(Modification 2)
Electronic devices to which the liquid crystal device 1 according to the first embodiment can be applied are not limited to the projector 100 and the video camera 200. 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 video camera, or a car navigation system. It can be suitably used as a display unit of an information terminal device such as a system, electronic notebook, or POS.

  Further, an electronic apparatus to which the imaging device 6 according to the fourth embodiment can be applied is not limited to the video camera 200. The imaging device 6 can be suitably used as an imaging unit of an information terminal device such as a digital still camera, a mobile phone or a smartphone having an imaging function.

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal device (electro-optical device), 6 ... Imaging device (electro-optical device), 10, 10A, 10B ... Microlens array substrate (second substrate), 11 ... Substrate, 11a ... Surface (front surface), 12 ... Concave part, 13 ... lens layer (first lens layer), 15 ... lens layer (second lens layer), 16 ... convex part, 16a ... central part, 16b ... peripheral part, 20 ... element substrate (first substrate) Substrate), 24 ... TFT (switching element), 30 ... Counter substrate (second substrate), 40 ... Liquid crystal layer (electro-optical layer), 60 ... Light receiving element substrate (first substrate), 63 ... Light receiving element, 100 ... projector (electronic device), 200 ... video camera (electronic device), ML1 ... microlens (first microlens), ML2, ML2e ... microlens (second microlens), P ... pixel, S ... light shielding part , T ... opening.

Claims (9)

A substrate,
A first microlens disposed on the substrate;
A second microlens disposed on the first microlens so as to overlap the first microlens in plan view;
The second microlens has a central part configured by a curved surface, and a peripheral part arranged outside the central part,
The microlens array substrate, wherein a curvature of the peripheral portion is smaller than a curvature of the central portion. The microlens array substrate according to claim 1,
The microlens array substrate, wherein the peripheral portion includes a tapered inclined surface. The microlens array substrate according to claim 1 or 2,
The first microlens is formed of a material having a refractive index larger than the refractive index of the substrate so as to fill a recess provided in the substrate.
The second microlens is made of a material having a refractive index larger than the refractive index of the substrate, and is formed in a convex shape protruding to the opposite side of the first microlens. Array substrate. The microlens array substrate according to claim 3,
The microlens array substrate, wherein a cross-sectional shape of the second microlens is substantially symmetric with respect to a vertex of the central portion. A first substrate comprising: a switching element provided for each pixel; and a light shielding portion having an opening for each pixel and provided to overlap the switching element in plan view;
A second substrate comprising the microlens array substrate according to any one of claims 1 to 4 and disposed to face the first substrate;
An electro-optic layer disposed between the first substrate and the second substrate,
The electro-optical device, wherein the first microlens and the second microlens are arranged so as to overlap with the opening of each pixel in a plan view. A first substrate including a light receiving element provided for each pixel, and a light shielding portion having an opening for each pixel;
A second substrate including the microlens array substrate according to any one of claims 1 to 4 and disposed to face the first substrate,
The electro-optical device, wherein the first microlens, the second microlens, and the light receiving element are arranged so as to overlap the opening of each pixel in a plan view.   An electronic apparatus comprising the electro-optical device according to claim 5. Forming a recess on the surface of the substrate;
Forming a first lens layer with a material having a refractive index greater than the refractive index of the substrate so as to fill the concave portion of the substrate;
On the first lens layer, a second lens layer having a convex portion which is made of a material having a refractive index larger than the refractive index of the substrate and is arranged so as to overlap with the concave portion in a plan view and configured by a curved surface. Forming a step, and
The convex part has a central part and a peripheral part arranged outside the central part,
The method of manufacturing a microlens array substrate, wherein the curvature of the peripheral portion is smaller than the curvature of the central portion.   A method for manufacturing an electro-optical device, comprising the method for manufacturing a microlens array substrate according to claim 8.

Images