JP6364912B2 - Microlens array substrate, electro-optical device, and electronic device - Google Patents

Description

  The present invention relates to a microlens array substrate, an electro-optical device using the microlens array substrate, and an electronic apparatus using the electro-optical device.

  As an electro-optical device, for example, an active drive type liquid crystal device used for a light modulation element (light valve) of a liquid crystal projector is known. The liquid crystal device includes an element substrate having a pixel electrode, a counter substrate disposed opposite to the element substrate and having a common electrode, a liquid crystal layer sandwiched between the element substrate and the counter substrate, and a brighter display is desired.

For example, each pixel is provided with a microlens as a light condensing part, and the light that does not contribute to the display is condensed by the microlens and used for a part of the display light, thereby improving the light utilization efficiency. A liquid crystal device that realizes a bright display has been proposed (Patent Document 1).
In the liquid crystal device described in Patent Document 1, two types of films having different refractive indexes are stacked on a counter substrate having a recess, and two types of microlenses are formed at positions corresponding to the recess. Since the two types of microlenses are formed by depositing a film in the concave portion, for example, a photolithography process or an etching process is omitted, and labor and cost for manufacturing the microlens are reduced. Furthermore, the light incident on the counter substrate is condensed by two types of microlenses, and the display brightness is enhanced.

JP 2013-57781 A

For example, when light in a direction crossing the direction from the counter substrate to the element substrate, that is, light in an oblique direction, enters the liquid crystal layer, the light is completely blocked even if the liquid crystal layer has a black display molecular arrangement. There was a risk that the display contrast could be reduced. That is, the light in the oblique direction does not enter the liquid crystal layer having a black display molecular arrangement at an ideal angle, so that the polarized light cannot be aligned, light leakage (black floating) occurs, and the display contrast is reduced. There was a risk of decline.
In the liquid crystal device described in Patent Document 1, since the light condensed by the two types of microlenses described above includes a light component that is incident on the liquid crystal layer in an oblique direction, the display contrast may be reduced.

  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 transparent substrate having a first surface provided with a concave portion, and a first substrate that covers the first surface and has a first convex portion inside the concave portion. A first lens layer having two surfaces and a flat third surface disposed on the opposite side of the second surface, a fourth surface covering the third surface, and disposed on the opposite side of the fourth surface. A second lens layer including a fifth surface having a second convex portion corresponding to the first convex portion, and disposed on the opposite side of the surface that covers the fifth surface and contacts the fifth surface A transparent film having a flat surface, wherein the refractive index of the first lens layer is higher than the refractive index of the transparent substrate, and the refractive index of the second lens layer is that of the first lens layer. The refractive index is the same as or lower than the refractive index of the first lens layer, and the refractive index of the transparent film is higher than the refractive index of the second lens layer. The features.

  By providing the first convex portion having a higher refractive index than the concave portion inside the concave portion, the first convex portion functions as a lens having a positive refractive power. By covering the second convex part with a transparent film having a higher refractive index than the second convex part, the second convex part functions as a lens having negative refractive power.

Since the first convex portion has positive refractive power, the light in the normal direction of the first surface (parallel light) incident on the first convex portion converges on the focal point of the first convex portion ( The light is refracted in the direction of light collection, the brightness of the light is increased, and the light is incident on the second convex portion as light in a direction intersecting the normal direction of the first surface. Since the second convex portion has a negative refractive power, the light incident on the second convex portion is refracted in a direction diverging from the focal point of the second convex portion. Therefore, the light incident on the second convex portion is refracted in the direction opposite to the direction refracted by the first convex portion, that is, refracted in the direction in which the angle with the normal direction of the first surface is reduced. Therefore, the second convex portion can emit light in a direction intersecting the normal direction of the first surface close to the light (parallel light) in the normal direction of the first surface.
Therefore, the brightness of the light in the normal direction of the first surface (parallel light) can be increased by condensing the light by the first convex part and bringing the traveling direction of the light close to the original state by the second convex part. it can.

The light in the direction (oblique direction) intersecting the normal direction of the first surface is refracted by the first convex portion in a direction in which the angle formed by the first convex portion and the normal direction of the first surface is increased, Incident on the second convex portion. When viewed from the normal direction of the first surface, the intersection of the light refracted by the first convex portion (refracted light of oblique direction light) and the second convex portion, and refracted by the first convex portion described above When the intersection of the light (refracted light in the normal direction of the first surface) and the second convex portion is disposed on the opposite side with respect to the focal point of the second convex portion, the first The light refracted by the convex part (refracted light of oblique light) is refracted by the second convex part by the first convex part (refracted light in the normal direction of the first surface). ) Is refracted in the direction opposite to the refraction direction. That is, the light incident on the second convex portion is not refracted in a direction in which the angle formed with the normal direction of the first surface is reduced by the second convex portion, but the angle formed with the normal direction of the first surface is reduced. Further, the light is refracted in a larger direction.
Therefore, the path of light in the direction (diagonal direction) intersecting the normal direction of the first surface in a direction in which the angle formed with the normal direction of the first surface is increased by the first and second convex portions. Can be changed.

  Application Example 2 In the microlens array substrate according to the application example described above, it is preferable that the refractive index of the second lens layer is the same as the refractive index of the first lens layer.

  Since the refractive index of the first lens layer is the same as the refractive index of the second lens layer, that is, the first lens layer and the second lens layer are formed of the same material, the first lens layer and the second lens layer are the same. Compared to a configuration formed of different materials, the process of forming the first lens layer and the second lens layer (for example, a film forming process) is simplified, and the first convex part and the second convex part The distance between them can be reduced.

  Application Example 3 In the microlens array substrate according to the application example described above, it is preferable that the refractive index of the second lens layer is lower than the refractive index of the first lens layer.

The first lens layer and the second lens layer are made of materials having different refractive indexes. For example, when the first lens layer is made of a material having a high stress (for example, SiON), the second lens layer is made of a material having a low stress (for example, SiO ₂ ), so that the stress of the first lens layer is reduced. It is possible to suppress adverse effects due to the large size, such as warpage and cracks.

  Application Example 4 A microlens array substrate according to this application example has a second surface that covers the first surface of the transparent substrate, and a third surface having a first convex portion disposed on the opposite side of the second surface. And a fourth surface covering the third surface, and a second convex portion corresponding to the first convex portion disposed on the opposite side of the fourth surface. A second lens layer having a surface, and a transparent film that covers the fifth surface and has a flat surface disposed on the opposite side of the surface in contact with the fifth surface, the first lens layer Is higher than the refractive index of the transparent substrate, the refractive index of the second lens layer is lower than the refractive index of the first lens layer, and the refractive index of the transparent film is the second lens layer. It is characterized by being higher than the refractive index.

  By covering the first convex portion with the second lens layer having a lower refractive index than the first convex portion, the first convex portion functions as a lens having a positive refractive power. By covering the second convex part with a transparent film having a higher refractive index than the second convex part, the second convex part functions as a lens having negative refractive power.

Therefore, the brightness of the light in the normal direction of the first surface (parallel light) can be increased by condensing the light by the first convex part and bringing the traveling direction of the light close to the original state by the second convex part. it can.
Furthermore, the light path in the direction (diagonal direction) intersecting the normal direction of the first surface in a direction in which the angle formed with the normal direction of the first surface is increased by the first and second convex portions. Can be changed.

  Application Example 5 A microlens array substrate according to this application example has a second surface that covers the first surface of the transparent substrate, and a third surface having a first convex portion disposed on the opposite side of the second surface. A first lens layer that includes: a first transparent film that covers the third surface and includes a flat surface disposed on the opposite side of the surface that contacts the third surface; and covers the flat surface. A second transparent film having a surface provided with a recess corresponding to the first protrusion disposed on the opposite side of the surface in contact with the flat surface; and covering the surface provided with the recess; A second lens layer having a fourth surface having a second convex portion inside and a flat fifth surface disposed on the opposite side of the fourth surface, and The refractive index is higher than the refractive index of the transparent substrate, the refractive index of the first transparent film is lower than the refractive index of the first lens layer, and the second transparent film The refractive index is the same as the refractive index of the first transparent film or higher than the refractive index of the first transparent film, and the refractive index of the second lens layer is lower than the refractive index of the second transparent film. Features.

  By covering the first convex portion with the first transparent film having a lower refractive index than the first convex portion, the first convex portion functions as a lens having a positive refractive power. By providing the second convex portion having a lower refractive index than the concave portion inside the concave portion, the second convex portion functions as a lens having negative refractive power.

Therefore, the brightness of the light in the normal direction of the first surface (parallel light) can be increased by condensing the light by the first convex part and bringing the traveling direction of the light close to the original state by the second convex part. it can.
Furthermore, the light path in the direction (diagonal direction) intersecting the normal direction of the first surface in a direction in which the angle formed with the normal direction of the first surface is increased by the first and second convex portions. Can be changed.

  Application Example 6 In the microlens array substrate according to the application example described above, it is preferable that the refractive index of the second transparent film is the same as the refractive index of the first transparent film.

  The refractive index of the first transparent film and the refractive index of the second transparent film are the same, that is, the first transparent film and the second transparent film are formed of the same material, so the first transparent film and the second transparent film Compared to a structure formed of different materials, the process of forming the first transparent film and the second transparent film (for example, a film forming process) is simplified, and the transparent film can be made thinner.

  Application Example 7 In the microlens array substrate according to the application example described above, it is preferable that the refractive index of the second transparent film is higher than the refractive index of the first transparent film.

The first transparent film and the second transparent film are made of materials having different refractive indexes. For example, when the second transparent film is made of a material having a high stress (for example, SiON), the first transparent film layer is made of a material having a low stress (for example, SiO ₂ ). It is possible to suppress adverse effects due to the large stress, such as warpage and cracks.

  Application Example 8 An electro-optical device according to this application example includes an element substrate having a pixel electrode, a counter substrate having a common electrode, and an electro-optical material sandwiched between the element substrate and the counter substrate. The element substrate or the counter substrate includes the microlens array substrate described in the application example.

  In the microlens array substrate according to the application example described above, the light in the normal direction of the first surface is collected by the first convex portion and the traveling direction of the light is brought close to the original state by the second convex portion. The brightness of (parallel light) can be increased. Therefore, when the microlens array substrate is applied to either the element substrate or the counter substrate, the utilization efficiency of the light in the normal direction of the first surface is improved as compared with the case where the microlens array substrate is not applied. , Display brightness can be increased.

  Furthermore, the light path in the direction (diagonal direction) intersecting the normal direction of the first surface in a direction in which the angle formed with the normal direction of the first surface is increased by the first and second convex portions. Can be changed. For example, when the microlens array substrate is not provided, the influence of the oblique light on the display can be reduced by changing the path of the oblique light that becomes the display light and blocking it with the light shielding portion. Therefore, it is possible to suppress the display contrast from being lowered by the light in the oblique direction, which is a problem of the known technique (Japanese Patent Laid-Open No. 2013-57781), and to improve the display quality.

  Application Example 9 In the electro-optical device according to the application example, the counter substrate includes the microlens array substrate according to the application example, and the element substrate has light in a direction from the counter substrate toward the element substrate. It is preferable to provide a light shielding part that shields the light.

  By applying the microlens array substrate to the counter substrate and providing the light shielding portion on the element substrate, the layer provided with the electro-optical material disposed between the counter substrate and the element substrate is adjusted to a desired optical path length. It can be used for a part of the optical path length adjusting layer.

  Application Example 10 An electronic apparatus according to this application example includes the electro-optical device described in the application example.

In the electro-optical device described in the above application example, display brightness and display quality can be improved by the microlens array substrate, that is, a bright high-quality display can be provided. Therefore, a bright and high-quality display can be provided even in an electronic apparatus including the electro-optical device described in the application example.
For example, a projection display device, a projection type HUD (head-up display), a direct view type HMD (head mounted display), an electronic book, a personal computer, a digital still camera, a liquid crystal television, a viewfinder type or a monitor direct view type video recorder By applying the electro-optical device described in the application example to an information terminal device such as a car navigation system, a POS, and an electronic device such as an electronic notebook, a bright and high-quality display can be provided.

FIG. 2 is a schematic plan view showing the configuration of the liquid crystal device according to the first embodiment. FIG. 3 is an equivalent circuit diagram illustrating an electrical configuration of the liquid crystal device according to the first embodiment. FIG. 2 is a schematic cross-sectional view of the liquid crystal device along the line A-A ′ of FIG. 1. FIG. 4 is a schematic cross-sectional view of the liquid crystal device in a region B surrounded by a broken line in FIG. 3. FIG. 4 is a schematic cross-sectional view of a liquid crystal device according to Embodiment 2. FIG. 6 is a schematic cross-sectional view of the liquid crystal device in a region B surrounded by a broken line in FIG. 5. FIG. 6 is a schematic cross-sectional view of a liquid crystal device according to a third embodiment. FIG. 8 is a schematic cross-sectional view of the liquid crystal device in a region B surrounded by a broken line in FIG. 7. FIG. 6 is a schematic diagram illustrating a configuration of a projector according to a fourth embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. Such an embodiment shows one aspect of the present invention and does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. In each of the following drawings, the scale of each layer or each part is made different from the actual scale so that each layer or each part can be recognized on the drawing.

(Embodiment 1)
"Outline of LCD device"
The liquid crystal device 71 according to the first embodiment is an example of the “electro-optical device” in the present invention, and can be suitably used as, for example, a light modulation element (liquid crystal light valve) of a projector (projection display device) described later. Is.

FIG. 1 is a schematic plan view showing the configuration of the liquid crystal device according to the present embodiment. FIG. 2 is an equivalent circuit diagram showing an electrical configuration of the liquid crystal device according to the present embodiment. FIG. 3 is a schematic cross-sectional view of the liquid crystal device taken along line AA ′ of FIG.
First, an outline of the liquid crystal device 71 according to the present embodiment will be described with reference to FIGS. 1 to 3.

As shown in FIGS. 1 and 3, the liquid crystal device 71 according to the present embodiment includes an element substrate 20 having a pixel electrode 28, a counter substrate 30 having a common electrode 34 disposed opposite to the element substrate 20, and the element substrate 20. A liquid crystal layer 40 sandwiched between the counter substrate 30 and the like is provided. As shown in FIG. 1, the element substrate 20 is larger than the counter substrate 30, and both the substrates are bonded via a sealing material 42 arranged in a frame shape along the peripheral edge of the counter substrate 30.
The liquid crystal layer 40 is an example of the “electro-optical material” in the present invention.

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

Inside the sealing material 42 arranged in a frame shape, the light shielding layers 22 and 26 provided on the element substrate 20 and the light shielding layer 32 provided on the counter substrate 30 are arranged. The light shielding layers 22, 26, and 32 have a frame-like peripheral portion, and are formed of, for example, a light shielding metal or metal oxide. Inside the frame-shaped light shielding layers 22, 26, 32 is a display area E in which a plurality of pixels P are arranged. The pixels P have a substantially rectangular shape, for example, and are arranged in a matrix.
The liquid crystal device 71 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 is provided between the sealing material 42 along one side of the element substrate 20 and the one side. Further, an inspection circuit 53 is provided between the seal material 42 and the display area E along the other one side facing the one side. Further, a scanning line drive circuit 52 is provided between the seal material 42 and the display region E along the other two sides that are orthogonal to the one side and face each other. A plurality of wirings 55 that connect the two scanning line driving circuits 52 are provided between the sealing material 42 and the inspection circuit 53 along the other one side facing the one side.

  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 arranged along the one side. 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 one side is defined as the X direction, and the direction along the other two sides orthogonal to the one side and facing each other is defined as the Y direction. A direction from the counter substrate 30 toward the element substrate 20 is defined as a Z (+) direction.
Note that viewing from the side of the counter substrate 30 along the Z (+) direction is referred to as a 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 thin film transistor (hereinafter referred to as 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 71 as a whole.

"Outline of element substrate"
As shown in FIG. 3, in the element substrate 20, the substrate 21, 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 orientation The film 29 is stacked in order in the Z (−) direction.
The substrate 21 is made of a light transmissive material such as glass or quartz.

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

  By providing the light shielding layer 22 and the light shielding layer 26, 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. Further, the light blocking layer 22 and the light blocking layer 26 form a light blocking portion V1 that blocks light. Further, a portion surrounded by the light shielding portion V1 is an opening portion V2 that transmits light.

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 (light shielding portion V1) 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 so as to overlap with a region surrounded by the light shielding layer 22 and the light shielding layer 26 and a part of the light shielding layer 22 and the light shielding layer 26 in a 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.

  Although not shown in the drawing, in a region overlapping the light shielding layer 22 and the light shielding layer 26 (light shielding portion V1) in plan view, an electrode for supplying an electrical signal to the TFT 24, a wiring, a relay electrode, and a storage capacitor 5 ( The capacitor electrode etc. which comprise (refer FIG. 2) are provided. Further, the light shielding layer 22 and the light shielding layer 26 may be configured to include these electrodes, wirings, relay electrodes, capacitor electrodes, and the like.

"Overview of the counter substrate"
In a projector (see FIG. 9) described later, light emitted from a light source (polarized illumination device 110, see FIG. 9) is incident on the counter substrate 30, travels along the Z (+) direction, and is a liquid crystal layer. 40 passes through the element substrate 20 and is emitted. That is, in the liquid crystal device 71 according to this embodiment, light enters the counter substrate 30 and light is emitted from the element substrate 20.
In the following description, the surface on which light is incident is the lower surface, and the surface on which light is emitted is the upper surface.

In the counter substrate 30 according to the present embodiment, a microlens array substrate 10, a light shielding layer 32, a protective layer 33, a common electrode 34, and an alignment film 35 are sequentially stacked in the Z (+) direction.
The microlens array substrate 10 includes a substrate 11, a first lens layer 13, a second lens layer 15, and a transparent film 7 that are sequentially stacked in the Z (+) direction.
The substrate 11 includes a lower surface 11b on which light is incident and an upper surface 11a on which light is emitted. The first lens layer 13 includes a lower surface 13b on which light is incident and an upper surface 13a on which light is emitted. The second lens layer 15 includes a lower surface 15b on which light is incident and an upper surface 15a on which light is emitted. The transparent film 7 includes a lower surface 7b on which light is incident and an upper surface 7a on which light is emitted.
The light incident on the lower surface 11b of the substrate 11 includes the upper surface 11a of the substrate 11, the lower surface 13b and the upper surface 13a of the first lens layer 13, the lower surface 15b and the upper surface 15a of the second lens layer 15, and the lower surface 7b of the transparent film 7. And is emitted from the upper surface 7a of the transparent film 7 to the protective layer 33.

The substrate 11 is an example of the “transparent substrate” in the present invention. The upper surface 11a of the substrate 11 is an example of the “first surface” in the present invention. The lower surface 13b of the first lens layer 13 is an example of the “second surface” in the present invention, and the upper surface 13a of the first lens layer 13 is an example of the “third surface” in the present invention. The lower surface 15b of the second lens layer 15 is an example of the “fourth surface” in the present invention, and the upper surface 15a of the second lens layer 15 is an example of the “fifth surface” in the present invention.
Furthermore, the lower surface 7b of the transparent film 7 is an example of the “surface that contacts the fifth surface” in the present invention, and the upper surface 7a of the transparent film 7 is an example of the “flat surface” in the present invention.

The substrate 11 has optical transparency and is made of, for example, a quartz glass substrate (SiO ₂ , refractive index (589.3 nm): 1.46). A plurality of recesses 12 are provided on the upper surface 11 a of the substrate 11. The recess 12 is provided for each pixel P, and has a shape recessed in the direction (Z (+) direction) in which light travels (Z (+) direction).

  The recess 12 is formed by forming a mask having small holes formed on the upper surface 11a of the substrate 11 by a method such as photo etching or laser irradiation, and using the etching solution containing hydrofluoric acid, the substrate 11 is formed through the small holes. It is formed by isotropic etching.

  The first lens layer 13 is provided so as to cover the upper surface 11 a of the substrate 11. That is, the lower surface 13 b of the first lens layer 13 is in contact with the upper surface 11 a of the substrate 11. The lower surface 13 b of the first lens layer 13 has a first convex portion 14 disposed inside the concave portion 12. The 1st convex part 14 is shown with the thick broken line in the figure, and has the shape which became convex in the direction (Z (+) direction) where light advances (Z (-) direction). . The upper surface 13a of the first lens layer 13 is flattened by, for example, a flattening process by CMP (Chemical Mechanical Polishing).

The first lens layer 13 is made of a material having optical transparency and a higher refractive index than that of the substrate 11. A constituent material of the first lens layer 13 is SiON formed by a method such as plasma CVD (Chemical Vapor Deposition). SiON is composed of SiO ₂ (refractive index (589.3 nm): n = 1.46) and Si ₃ N ₄ (refraction) by changing the composition (ratio) of oxygen atoms (O) and nitrogen atoms (N). The refractive index can be adjusted (changed) between the refractive index (589.3 nm) and n = 2.00). That is, the first lens layer 13 made of SiON has a higher refractive index than the substrate 11 made of SiO ₂ .

The first convex portion 14 is formed by embedding SiON in the concave portion 12 formed on the upper surface 11 a of the substrate 11. Further, the first lens layer 13 (SiON) is formed thicker than the depth of the concave portion 12, and the first convex portion 14 disposed inside the concave portion 12, the first convex portion 14, and the second lens layer 15. The flat part 14a arrange | positioned between these.
The first lens layer 13 includes a lower surface 13b that covers the upper surface 11a of the substrate 11 and has a first convex portion 14 inside the concave portion 12, and a flat upper surface 13a that faces the lower surface 13b.

The second lens layer 15 is provided so as to cover the upper surface 13 a of the first lens layer 13. That is, the lower surface 15 b of the second lens layer 15 is in contact with the upper surface 13 a of the first lens layer 13. A second convex portion 16 corresponding to the first convex portion 14 is provided on the upper surface 15 a of the second lens layer 15. The second convex portion 16 has a shape that is convex in the light traveling direction (Z (+) direction), overlaps with the first convex portion 14 in plan view, and is provided for each pixel P. .
The second lens layer 15 is light transmissive and is made of a material having a lower refractive index than the first lens layer 13. The constituent material of the second lens layer 15 is, for example, SiO ₂ formed by a method such as plasma CVD.

For example, the second convex portion 16 is formed by depositing (depositing) SiO ₂ that covers the upper surface 13a of the first lens layer 13, and then is a photo that overlaps the first convex portion 14 in plan view on the upper surface 15a of the second lens layer 15. A resist is formed, and anisotropic dry etching is performed using the photoresist as an etching mask. Specifically, the photoresist formed on the upper surface 15a of the second lens layer 15 is subjected to heat treatment to soften the photoresist, and a photoresist having the same shape as the second convex portion 16 is formed. Subsequently, when anisotropic dry etching is performed on the second lens layer 15 using the photoresist as an etching mask, the shape (convex shape) of the photoresist is transferred to the upper surface 15 a of the second lens layer 15. That is, the second convex portion 16 is formed by subjecting the film (SiO ₂ ) deposited on the upper surface 13a of the first lens layer 13 to anisotropic dry etching.

  The second lens layer 15 includes a second convex portion 16 and a flat portion 16 a disposed between the second convex portion 16 and the first lens layer 13. The second lens layer 15 includes a lower surface 15 b that covers the upper surface 13 a of the first lens layer 13, and an upper surface 15 a that has a second convex portion 16 that faces the lower surface 15 b and corresponds to the first convex portion 14. .

The transparent film 7 has a light transmission property and is made of a material having a higher refractive index than that of the second lens layer 15. The transparent film 7 is, for example, SiON formed by a method such as plasma CVD, and is provided so as to cover the upper surface 15 a of the second lens layer 15. The lower surface 7 b of the transparent film 7 has a recess 8 that covers the second protrusion 16. The upper surface 7a of the transparent film 7 is flattened by, for example, CMP.
The transparent film 7 includes a concave portion 8 disposed on the second lens layer 15 side, and a flat portion 8 a disposed between the concave portion 8 and the protective layer 33. The transparent film 7 covers the upper surface 15a of the second lens layer 15, and has a flat upper surface 7a on the side facing the lower surface 7b.

The light shielding layer 32 is provided in a frame shape on the transparent film 7 (microlens array substrate 10) so as to surround the display area E (see FIG. 1).
The light shielding layer 32 may be provided in the display area E. For example, in the display area E, the light shielding layer 32 may be formed in a lattice shape so as to overlap the light shielding layer 22 and the light shielding layer 26 of the element substrate 20 in plan view, or may be formed in an island shape or a stripe shape.

A protective layer 33 is provided so as to cover the transparent film 7 and the light shielding layer 32. The protective layer 33 is made of, for example, an inorganic material such as SiO ₂ and is formed so as to cover the light shielding layer 32 so that the surface on the liquid crystal layer 40 side where the common electrode 34 is formed is flat.
A 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, for example, a transparent conductive material such as ITO or IZO (Indium Zinc Oxide).
Note that the common electrode 34 may be provided so as to directly cover the conductive light shielding layer 32 without providing the protective layer 33.
An alignment film 35 is provided so as to cover the common electrode 34.

"State of light passing through the liquid crystal device"
FIG. 4 is a schematic cross-sectional view of the liquid crystal device in a region B surrounded by a broken line in FIG. 3, and shows a state of light passing through the liquid crystal device.
4, illustration of the light shielding layer 32, the protective layer 33, the common electrode 34, and the alignment film 35 in the counter substrate 30 is omitted, and the illustration of the insulating layer 27, the pixel electrode 28, and the alignment film 29 in the element substrate 20 is omitted. Has been.

Furthermore, in the same figure, the lights L1 and L2 passing through the liquid crystal device 71 are indicated by solid arrows. The light L1 is light that travels in the Z (+) direction, and the light L2 is light that travels in a direction that intersects the Z (+) direction. When the microlens array substrate 10 is not provided, the light L1 is light that is blocked by the light blocking portion V1 and is not used as display light, as indicated by a dashed arrow in the drawing. When the microlens array substrate 10 is not provided, the light L2 is light that is emitted from the opening V2 and becomes display light, as indicated by a dashed arrow in the drawing.
Next, the state of light passing through the liquid crystal device 71 will be described with reference to FIG.

In the microlens array substrate 10, the first convex portion 14 is made of a high refractive index material (SiON), and the concave portion 12 covering the first convex portion 14 is made of a low refractive index material (SiO ₂ ). As a result, the first convex portion 14 has a positive refractive power. That is, the 1st convex part 14 functions as a lens which has positive refractive power (power). For example, when parallel rays in the Z (+) direction are incident on the first convex portion 14, the parallel rays are converged (condensed) toward the focal point of the first convex portion 14.

The second convex portion 16 is made of a low refractive index material (SiO ₂ ), and the concave portion 8 covering the second convex portion 16 is made of a high refractive index material (SiON). As a result, the second convex portion 16 has a negative refractive power. That is, the 2nd convex part 16 functions as a lens which has negative refractive power (power). For example, when parallel rays in the Z (+) direction are incident on the second convex portion 16, the parallel rays are diverged (diffused) from the focal point of the second convex portion 16.

  As described above, the microlens array substrate 10 has a positive refractive power lens (first convex portion 14) on the light incident side and a negative refractive power lens (first projection) on the light emission side. 2 convex portions 16) are arranged. That is, the microlens array substrate 10 includes a positive refractive power lens (first convex portion 14) and a negative refractive power lens (second convex portion) along the Z (+) direction in which the light L1 travels. 16) are arranged (stacked) in order.

P1 in the figure is an intersection of the curved surface (lens surface) of the first convex portion 14 and the light L1, and P1
Reference numeral 3 denotes an intersection of the curved surface (lens surface) of the first convex portion 14 and the light L2. P2 in the figure is the intersection of the curved surface (lens surface) of the second convex portion 16 and the light L1, and P4 is the intersection of the curved surface (lens surface) of the second convex portion 16 and the light L2.
In plan view, the focal point (not shown) of the first convex portion (lens having positive refractive power) 14 is arranged in the X (−) direction with respect to P1 and P3. That is, P1 and P3 are disposed on the same side with respect to the focal point of the first convex portion 14 in plan view.
In plan view, the focal point (not shown) of the second convex portion (lens having negative refractive power) 16 is disposed between P2 and P4. That is, P2 and P4 are arranged on the opposite side with respect to the focal point of the second convex portion 16 in plan view.

  Since the first convex portion 14 has a positive refractive power (power), the light L1 in the Z (+) direction incident on P1 of the curved surface (lens surface) of the first convex portion 14 is Z The light is refracted in the direction in which the angle formed with the (+) direction increases. That is, the light L1 in the Z (+) direction incident on the lens surface P1 of the first convex portion 14 is refracted in a direction intersecting with the Z (+) direction and is light in a direction intersecting with the Z (+) direction. L1 is incident on P2 of the lens surface of the second convex portion 16.

  Since the second convex part 16 has negative refractive power (power), the light L1 in the direction intersecting with the Z (+) direction incident on P2 of the second convex part 16 is the first The light is refracted in the direction opposite to the direction refracted by the convex portion 14. Therefore, the light L1 in the direction intersecting with the Z (+) direction is refracted by the second convex portion 16 in a direction in which the angle formed with the Z (+) direction becomes smaller, and becomes light in the Z (+) direction. It passes through the layer 40 and is emitted from the opening V2.

  As described above, the light L1 in the Z (+) direction that is not used for display light when the microlens array substrate 10 is not provided becomes display light in the Z (+) direction by the microlens array substrate 10, so that the light The use efficiency can be improved, and the display brightness can be increased.

  Furthermore, since the light L1 is refracted by the first convex portion 14, and then refracted by the second convex portion 16 in the direction opposite to the direction refracted by the first convex portion 14, the first convex portion 14 and The influence of chromatic aberration can be reduced as compared with the case where both the second convex portions 16 are refracted in the same direction.

When light in a direction (diagonal direction) intersecting the Z (+) direction is incident on the liquid crystal layer 40, even if the liquid crystal layer 40 has a black display molecular arrangement, the light cannot be completely blocked and the display contrast is reduced. There was a risk of decline. That is, the liquid crystal layer 40 having a black display molecular arrangement is not incident at an ideal angle, so that the polarization cannot be aligned and a normal black display cannot be performed (for example, black floating) occurs. There was a fear.
For example, when the light L2 in the direction intersecting with the Z (+) direction is emitted as display light from the opening V2, there is a possibility that the display contrast is lowered.

  The light L1 whose luminance is enhanced by the microlens array substrate 10 is incident on the liquid crystal layer 40 in the Z (+) direction, that is, an ideal angle with respect to the liquid crystal layer 40 having a black display molecular arrangement. Therefore, defects such as black floating are suppressed and high display contrast is realized.

  Since P3 is arranged on the same side as P1 with respect to the focal point of the first convex portion 14 in plan view, the light L2 in a direction intersecting the Z (+) direction incident on P3 of the first convex portion 14 Is refracted by the first convex portion 14 in the same direction as the light L1, that is, in a direction in which the angle formed with the Z (+) direction is increased, and is incident on P4 of the second convex portion 16.

  Since P4 is disposed on the opposite side of P2 with respect to the focal point of the second convex portion 16 in plan view, the light L2 incident on P4 of the second convex portion 16 is emitted by the second convex portion 16. Refraction occurs in the direction opposite to L1. Therefore, the light L2 incident on P4 of the second convex portion 16 is refracted in a direction in which the angle formed with the Z (+) direction is further increased, enters the light shielding portion V1, and is blocked by the light shielding portion V1.

  As described above, when the microlens array substrate 10 is not provided, the light L2 that may cause a decrease in display contrast is changed in the light traveling direction by the microlens array substrate 10 and is incident on the light shielding portion V1. The light is blocked by the light blocking portion V1 and is not emitted as display light. Therefore, the influence of the light L2 incident on the liquid crystal layer 40 in the oblique direction can be suppressed, and the display contrast can be increased.

  Further, the light L2 in the direction intersecting with the Z (+) direction is bent in a direction in which the angle formed with the Z (+) direction is further increased by both the first convex portion 14 and the second convex portion 16. If it is emitted as display light from the opening V2 of the adjacent pixel P, it is hard to contribute to image display by being kicked by a projection optical system (projection lens 117, see FIG. 9) of a projector (see FIG. 9) described later. Become. That is, when the angle formed by the light L2 with respect to the Z (+) direction is larger than the swallowing angle of the projection lens 117 (see FIG. 9) of the projector, which will be described later, the light L2 is kicked by the projection lens 117 to display an image. No longer contributes. Therefore, by refracting the light L2 in a direction in which the angle formed with the Z (+) direction is further increased, the light L2 does not contribute to the display of an image in the projector described later, and the display contrast in the projector can be increased.

  The flat portion 14a of the first lens layer 13, the flat portion 16a of the second lens layer 15, and the flat portion 8a of the transparent film 7 described above have a positive refractive power lens (first convex portion 14) and negative refraction. The distance (optical path length) from the force lens (second convex portion 16) to the light shielding layers 22 and 26 (light shielding portion V1) is adjusted to a desired value. That is, the flat portion 14 a of the first lens layer 13, the flat portion 16 a of the second lens layer 15, and the flat portion 8 a of the transparent film 7 serve as an optical path length adjustment layer in the microlens array substrate 10.

  The thicknesses of these optical path length adjusting layers are the focal lengths of the positive refractive power lens (first convex portion 14) and the negative refractive power lens (second convex portion 16) corresponding to the wavelength of light. It is set as appropriate based on the optical conditions. That is, the layer thicknesses of these optical path length adjustment layers are set so that the light collection capability of the microlens array substrate 10 is maximized.

  Furthermore, in the liquid crystal device 71 according to the present embodiment, the microlens array substrate 10 that collects light is provided on the counter substrate 30 side, and the light shielding portion V1 that blocks light is provided on the element substrate 20 side. The liquid crystal layer 40 also has a role of an optical path length adjusting layer for adjusting to a desired optical path length. By utilizing the liquid crystal layer 40 as a part of the optical path length adjusting layer, the optical path length adjusting layer (the flat portion 14a of the first lens layer 13, the flat portion 16a of the second lens layer 15 and the transparent layer) provided on the microlens array substrate 10 is used. For example, the productivity of the microlens array substrate 10 can be increased by reducing the layer thickness of the flat portion 8a) of the film 7.

  In the microlens array substrate 10, a new optical path length is adjusted between the first lens layer 13 and the second lens layer 15 and at least one of the transparent film 7 and the protective layer 33. The structure which has a transparent film (optical path length adjustment layer) may be sufficient.

Further, in the microlens array substrate 10, the substrate 11 is made of a quartz substrate (SiO ₂ ), the first lens layer 13 is made of SiON (high refractive index material), and the second lens layer 15 is made of SiO ₂ (low refractive index). The transparent film 7 is made of SiON (high refractive index material). The SiON constituting the first lens layer 13, the SiO ₂ constituting the second lens layer 15, and the SiON constituting the transparent film 7 are formed by plasma CVD, for example. SiON formed by plasma CVD has a higher stress than SiO ₂ formed by plasma CVD.
By interposing the second lens layer 15 composed of SiO ₂ having a small stress between the first lens layer 13 composed of SiON having a large stress and the transparent film 7, an adverse effect of the large stress (for example, , Warpage of the substrate, film peeling, etc.), that is, stress mismatch can be reduced.

As described above, in the liquid crystal device 71 according to this embodiment, the following effects can be obtained.
(1) Since the light L1 in the Z (+) direction, which is not used for display when the microlens array substrate 10 is not provided, enters the liquid crystal layer 40 as light in the Z (+) direction and is used as display light. The display brightness can be increased without causing a decrease in contrast.

  (2) Since the light (for example, the light L1) incident on the microlens array substrate 10 is refracted in the opposite direction by the first convex portion 14 and the second convex portion 16 and used for display light. The influence of chromatic aberration can be reduced compared to the case where the first convex portion 14 and the second convex portion 16 are refracted in the same direction and used for display light.

  (3) Since the light L2 that may cause a decrease in display contrast when the microlens array substrate 10 is not provided is blocked by the light shielding portion V1, the display contrast can be increased.

  (4) The light L2, which may cause a decrease in display contrast when the microlens array substrate 10 is not provided, has an angle formed with the Z (+) direction by the first convex portion 14 and the second convex portion 16. Since the light is further refracted, even if it is emitted as display light from the opening V2, it is kicked by the projection lens 117 of the projector, which will be described later, and does not contribute to the display of the image, thereby increasing the display contrast in the projector. it can.

  (5) The microlens array substrate 10 that condenses light is provided on the counter substrate 30 side, the light shielding portion V1 that blocks light is provided on the element substrate 20 side, and the liquid crystal layer 40 is used as part of the optical path length adjustment layer. Therefore, the optical path length adjustment layer provided on the microlens array substrate 10 side can be thinned, and for example, the productivity of the microlens array substrate 10 can be increased.

(6) A component (second lens layer 15) made of SiO ₂ having a low stress is interposed between components (first lens layer 13 and transparent film 7) made of SiON having a high stress. Therefore, the adverse effect (stress mismatch) of the large stress can be reduced.

(Embodiment 2)
FIG. 5 is a diagram corresponding to FIG. 3 and a schematic cross-sectional view of the liquid crystal device according to the second embodiment. 6 is a diagram corresponding to FIG. 4, and is a schematic cross-sectional view of the liquid crystal device in a region B surrounded by a broken line in FIG.

  The liquid crystal device 72 according to the present embodiment is different from the liquid crystal device 71 according to the first embodiment in the configuration of the microlens array substrate 10, and other configurations are the same as the liquid crystal device 71 according to the first embodiment. Specifically, the following contents are main differences between the microlens array substrate 10 of the present embodiment and the microlens array substrate 10 of the first embodiment.

(1) The concave portion 12 is not provided on the upper surface 11 a of the substrate 11.
(2) The first convex portion 14 is provided on the upper surface 13 a of the first lens layer 13.
(3) The 1st convex part 14 and the 2nd convex part 16 are formed by the method different from Embodiment 1. FIG.
Hereinafter, an outline of the liquid crystal device 72 according to the present embodiment will be described with reference to FIGS. 5 and 6 focusing on differences from the first embodiment. In addition, about the component same as Embodiment 1, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

"Outline of microlens array substrate"
As shown in FIG. 5, the microlens array substrate 10 according to this embodiment includes a substrate 11, a first lens layer 13, a second lens layer 15, and a transparent film 7, which are sequentially stacked in the Z (+) direction. It consists of and. That is, the microlens array substrate 10 according to the present embodiment has the same structure as the microlens array substrate 10 according to the first embodiment.

The substrate 11 is made of, for example, a quartz glass substrate (SiO ₂ ), and both the upper surface 11a and the lower surface 11b of the substrate 11 are flat.
The first lens layer 13 is made of a material having a higher refractive index than that of the substrate 11 (for example, SiON). The first lens layer 13 is provided so as to cover the upper surface 11 a of the substrate 11. That is, the lower surface 13 b of the first lens layer 13 is in contact with the upper surface 11 a of the substrate 11 and is flat. A first convex portion 14 is provided for each pixel P on the upper surface 13 a of the first lens layer 13.

  For example, after forming (depositing) SiON covering the upper surface 11a of the substrate 11 by plasma CVD, the first convex portion 14 forms a photoresist on the upper surface 13a of the first lens layer 13, and uses the photoresist as an etching mask. It is formed by performing anisotropic dry etching. Specifically, the photoresist formed on the upper surface 13a of the first lens layer 13 is subjected to heat treatment to soften the photoresist, and a photoresist having the same shape as the first convex portion 14 is formed. Subsequently, when anisotropic dry etching is performed on the first lens layer 13 using the photoresist as an etching mask, the shape (convex shape) of the photoresist is transferred to the upper surface 13 a of the first lens layer 13. That is, the first convex portion 14 is formed by subjecting the deposited film (SiON) to anisotropic dry etching.

The second lens layer 15 has a light transmission property and is made of a material (SiO ₂ ) having a lower refractive index than the first lens layer 13. The lower surface 15 b of the second lens layer 15 has a concave portion 16 b that contacts the upper surface 13 a of the first lens layer 13 and covers the first convex portion 14. A second convex portion 16 corresponding to the first convex portion 14 is provided on the upper surface 15 a of the second lens layer 15. The second convex portion 16 overlaps the first convex portion 14 in plan view and is provided for each pixel P.

The second convex portion 16 is formed by depositing SiO ₂ on the upper surface 13a of the first lens layer 13 provided with the first convex portion 14 by a method such as plasma CVD. Specifically, when SiO ₂ is deposited on the first convex portion 14, the shape of the first convex portion 14 is reflected on the upper surface 15 a of the second lens layer 15, and the second convex portion corresponding to the first convex portion 14. The portion 16 is formed in a self-aligning manner. Furthermore, a concave portion 16 b that covers the first convex portion 14 is formed on the lower surface 15 b of the second lens layer 15.

The second convex portion 16 of the first embodiment is formed by performing an etching process on the film (SiO ₂ ) deposited on the upper surface 13a of the first lens layer 13. Since the second convex portion 16 of the present embodiment is formed in a self-aligned manner simply by depositing SiO ₂ on the upper surface 13 a (first convex portion 14) of the first lens layer 13, Embodiment 1 Thus, the SiO ₂ etching process is simplified, and the productivity of the second protrusions 16 can be increased.

  The transparent film 7 has light transmittance and is made of a material (SiON) having a higher refractive index than that of the second lens layer 15. The lower surface 7 b of the transparent film 7 has a recess 8 that covers the second protrusion 16. The upper surface 7a of the transparent film 7 is flattened by, for example, CMP. That is, the transparent film 7 has a concave portion 8 disposed on the second lens layer 15 side, and a flat portion 8 a disposed between the concave portion 8 and the protective layer 33.

  In addition, the structure which has a new transparent film (optical path length adjustment layer) for adjusting to optical path length between the transparent film 7 and the protective layer 33 may be sufficient. In other words, a new transparent film (optical path length adjusting layer) for adjusting the optical path length may be provided on the surface (upper surface 7a) on the Z (+) direction side of the microlens array substrate 10.

"State of light passing through the liquid crystal device"
As shown in FIG. 6, the first convex portion 14 has a shape that is convex in the light traveling direction (Z (+) direction). The first convex portion 14 is made of a high refractive index material (SiON), and the concave portion 16b covering the first convex portion 14 is made of a low refractive index material (SiO ₂ ). As a result, the first convex portion 14 has a positive refractive power. That is, the 1st convex part 14 functions as a lens which has positive refractive power (power).

The 2nd convex part 16 has the shape which became convex in the direction (Z (+) direction) where light advances. The second convex portion 16 is made of a low refractive index material (SiO ₂ ), and the concave portion 8 covering the second convex portion 16 is made of a high refractive index material (SiON). As a result, the second convex portion 16 has a negative refractive power.

  In the microlens array substrate 10 according to the present embodiment, a lens having a positive refractive power (first convex portion 14) is disposed on the light incident side, and a lens having a negative refractive power is disposed on the light emitting side. The second convex portion 16) is arranged. Therefore, the microlens array substrate 10 according to the present embodiment has a positive refractive power lens (first convex portion 14) and a negative refractive power lens (in the Z (+) direction in which the light L1 travels). The second convex portions 16) are sequentially arranged (laminated), that is, the same configuration as the microlens array substrate 10 according to the first embodiment.

  Therefore, the light L1 in the Z (+) direction that is not used for display when the microlens array substrate 10 is not provided is used as display light, and when the microlens array substrate 10 is not provided, the display contrast is reduced. The light L2 incident on the liquid crystal layer 40 in the oblique direction is blocked by the light blocking portion V1. That is, the same effect as in the first embodiment can be obtained in this embodiment.

  As described above, the liquid crystal device 72 according to the present embodiment has the same effects as the effects (1) to (6) obtained by the liquid crystal device 71 according to the first embodiment. In addition, the following new effects can be obtained.

(1) Since the second convex portion 16 of the present embodiment is formed in a self-aligned manner simply by depositing SiO ₂ on the upper surface 13a (first convex portion 14) of the first lens layer 13, The SiO ₂ etching process in the first embodiment is simplified, and the productivity of the second protrusions 16 can be increased.

(Embodiment 3)
FIG. 7 corresponds to FIG. 3 and is a schematic cross-sectional view of the liquid crystal device according to the third embodiment. FIG. 8 is a diagram corresponding to FIG. 4, and is a schematic cross-sectional view of the liquid crystal device in a region B surrounded by a broken line in FIG. 7.

  The liquid crystal device 73 according to the present embodiment is different from the liquid crystal device 71 according to the first embodiment in the configuration of the microlens array substrate 10, and other configurations are the same as the liquid crystal device 71 according to the first embodiment. Specifically, the following contents are main differences between the microlens array substrate 10 of the present embodiment and the microlens array substrate 10 of the first embodiment.

(1) The concave portion 12 is not provided on the upper surface 11 a of the substrate 11.
(2) The first convex portion 14 is provided on the upper surface 13 a of the first lens layer 13.
(3) The transparent film 7 and the transparent film 17 are disposed between the first lens layer 13 and the second lens layer 15, and the concave portion 8 is provided on the upper surface 7 a of the transparent film 7. That is, it has the new transparent film 17 and the transparent film 7 in which the recessed part 8 was provided in the upper surface 7a.
(4) The second convex portion 16 is provided on the lower surface 15 b of the second lens layer 15.
Hereinafter, an outline of the liquid crystal device 73 according to the present embodiment will be described with reference to FIGS. 7 and 8 focusing on differences from the first embodiment. In addition, about the component same as Embodiment 1, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

"Outline of microlens array substrate"
As shown in FIG. 7, the microlens array substrate 10 includes a substrate 11, a first lens layer 13, a transparent film 17, a transparent film 7, and a second lens layer, which are sequentially stacked in the Z (+) direction. 15. The transparent film 17 has a lower surface 17b on which light is incident and an upper surface 17a on which light is emitted. The transparent film 7 has a lower surface 7b on which light is incident and an upper surface 7a on which light is emitted.
The transparent film 17 is an example of the “first transparent film” in the present invention, the lower surface 17b of the transparent film 17 is an example of the “surface in contact with the third surface” in the present invention, and the upper surface 17a of the transparent film 17 is It is an example of a “flat surface” in the present invention. The transparent film 7 is an example of the “second transparent film” in the present invention, the lower surface 7b of the transparent film 7 is an example of the “surface in contact with the flat surface” in the present invention, and the upper surface 7a of the transparent film 7 is the present invention. Is an example of “a surface provided with a recess”.

The substrate 11 is made of, for example, a quartz glass substrate (SiO ₂ ), and both the upper surface 11a and the lower surface 11b of the substrate 11 are flat.
The first lens layer 13 is made of a material (SiON) having a higher refractive index than that of the substrate 11. The first lens layer 13 is provided so as to cover the upper surface 11 a of the substrate 11, and the lower surface 13 b of the first lens layer 13 is in contact with the upper surface 11 a of the substrate 11 and is flat. A first convex portion 14 is provided for each pixel P on the upper surface 13 a of the first lens layer 13. The first protrusions 14 are formed by depositing SiON on the upper surface 11a of the substrate 11 and subjecting the deposited film (SiON) to anisotropic dry etching. That is, the 1st convex part 14 concerning this embodiment is formed by the same method as the 1st convex part 14 concerning Embodiment 2 mentioned above.

The transparent film 17 is made of a material having optical transparency and a refractive index lower than that of the first lens layer 13. The transparent film 17 is, for example, SiO ₂ formed by a method such as plasma CVD, and is provided so as to cover the upper surface 11 a of the substrate 11. The lower surface 17b of the transparent film 17 has a concave portion 18 that covers the first convex portion 14. The upper surface 17a of the transparent film 17 is flattened by, for example, CMP. That is, the transparent film 17 has a recess 18 disposed on the first lens layer 13 side and a flat portion 18 a disposed between the recess 18 and the transparent film 7.
The transparent film 17 covers the upper surface 13a of the first lens layer 13, and has a flat upper surface 17a on the side facing the lower surface 17b. Furthermore, the flat portion 18a of the transparent film 17 forms a part of an optical path length adjustment layer that adjusts the optical path length.

  The transparent film 7 is made of a material having optical transparency and a higher refractive index than the transparent film 17. The transparent film 7 is, for example, SiON formed by a method such as plasma CVD, and is provided so as to cover the upper surface 17 a of the transparent film 17. The lower surface 7 b of the transparent film 7 is in contact with the upper surface 17 a of the transparent film 17 and is flat. The upper surface 7a of the transparent film 7 is provided with a recess 8 that overlaps the first protrusion 14 in plan view.

  The concave portion 8 is formed by forming a mask in which small holes are formed by a method such as photoetching or laser irradiation on the upper surface 7a of the transparent film 7, and using, for example, an etching solution containing hydrofluoric acid, the transparent film through the small holes. 7 is formed by isotropic etching. That is, the recess 8 provided on the upper surface 7a of the transparent film 7 is formed by the same method as the recess 12 provided on the upper surface 11a of the substrate 11 according to the first embodiment.

The second lens layer 15 is made of a material having optical transparency and a refractive index lower than that of the transparent film 7. The second lens layer 15 is, for example, SiO ₂ formed by a method such as plasma CVD, and is provided so as to cover the upper surface 7 a of the transparent film 7. The lower surface 15 b of the second lens layer 15 is in contact with the upper surface 7 a of the transparent film 7, and a second convex portion 16 corresponding to the first convex portion 14 is provided. The upper surface 15a of the second lens layer 15 is flattened by, for example, CMP.

The second convex portion 16 is formed by embedding SiO ₂ in the concave portion 8 formed on the upper surface 7 a of the transparent film 7. Further, the second lens layer 15 is formed to be thicker than the depth of the concave portion 8 and is disposed between the second convex portion 16 disposed inside the concave portion 8 and between the second convex portion 16 and the protective layer 33. And a flat portion 16a.
The upper surface 15 a of the second lens layer 15 is a surface on the Z (+) direction side of the microlens array substrate 10, a frame-shaped light shielding layer 32 is provided, and is covered with a protective layer 33.

  In the present embodiment, the flat portion 18a of the transparent film 17, the flat portion 8a of the transparent film 7, and the flat portion 16a of the second lens layer 15 serve as an optical path length adjustment layer that adjusts to a desired optical path length.

  A new transparent film (optical path length adjusting layer) for adjusting to a desired optical path length between at least one of the transparent film 17 and the transparent film 7 and between the second lens layer 15 and the protective layer 33. The structure which has this may be sufficient.

In the microlens array substrate 10, the substrate 11 is composed of a quartz substrate (SiO ₂ ), the first lens layer 13 is composed of SiON (high refractive index material), and the transparent film 17 is composed of SiO ₂ (low refractive index material). The transparent film 7 is made of SiON (high refractive index material), and the second lens layer 15 is made of SiO ₂ (low refractive index material). SiON constituting the first lens layer 13, SiO ₂ constituting the transparent film 17, SiON constituting the transparent film 7, and SiO ₂ constituting the second lens layer 15 are formed by plasma CVD, for example. SiON formed by plasma CVD has a higher stress than SiO ₂ formed by plasma CVD. By interposing the transparent film 17 made of SiO ₂ having a small stress between the first lens layer 13 made of SiON having a large stress and the transparent film 7, an adverse effect of the large stress (for example, the substrate) Warping, film peeling, etc.), that is, stress mismatch can be reduced.

That is, in the present embodiment, a constituent element (transparent film 17) made of SiO ₂ having a low stress is interposed between constituent elements made of SiON having a high stress (the first lens layer 13 and the transparent film 7). Since it has the same configuration as the first embodiment, it is possible to obtain the same effect as that of the first embodiment in which the adverse effect (stress mismatch) due to the large stress is reduced.

"State of light passing through the liquid crystal device"
As shown in FIG. 8, the first convex portion 14 has a shape that is convex in the light traveling direction (Z (+) direction). The first convex portion 14 is made of a high refractive index material (SiON), and the concave portion 18 covering the first convex portion 14 is made of a low refractive index material (SiO ₂ ). As a result, the first convex portion 14 has a positive refractive power. That is, the 1st convex part 14 functions as a lens which has positive refractive power (power).

The 2nd convex part 16 has the shape which became convex in the direction (Z (+) direction) where light advances (Z (-) direction). The second convex portion 16 is made of a low refractive index material (SiO ₂ ), and the concave portion 8 covering the second convex portion 16 is made of a high refractive index material (SiON). As a result, the second convex portion 16 has a negative refractive power. That is, the 2nd convex part 16 functions as a lens which has negative refractive power (power).

  In the microlens array substrate 10 according to the present embodiment, a lens having a positive refractive power (first convex portion 14) is disposed on the light incident side, and a lens having a negative refractive power is disposed on the light emitting side. The second convex portion 16) is arranged. Therefore, the microlens array substrate 10 according to the present embodiment has a positive refractive power lens (first convex portion 14) and a negative refractive power lens (in the Z (+) direction in which the light L1 travels). The second convex portions 16) are sequentially arranged (laminated), that is, the same configuration as the microlens array substrate 10 according to the first embodiment.

Therefore, the light L1 in the Z (+) direction that is not used for display when the microlens array substrate 10 is not provided is used as display light, and when the microlens array substrate 10 is not provided, the display contrast is reduced. The light L2 incident on the liquid crystal layer 40 in the oblique direction is blocked by the light blocking portion V1. That is, the same effect as in the first embodiment can be obtained in this embodiment.
As described above, the liquid crystal device 73 according to the present embodiment has the same effects as the effects (1) to (6) obtained by the liquid crystal device 71 according to the first embodiment.

(Embodiment 4)
"Electronics"
FIG. 9 is a schematic diagram illustrating a configuration of a projector (projection display device) as an example of an electronic apparatus.
As shown in FIG. 9, the projector (projection display device) 100 according to the present embodiment includes a polarization illumination device 110, two dichroic mirrors 104 and 105, three reflection mirrors 106, 107, and 108, and five Relay lenses 111, 112, 113, 114, 115, three liquid crystal light valves 121, 122, 123, a cross dichroic prism 116, and a projection lens 117 are provided.

  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 one to which any of the liquid crystal devices 71, 72, 73 provided with the microlens array substrate 10 of the above-described embodiment is applied. The liquid crystal light valve 121 is arranged with a gap between a pair of polarizing elements arranged in crossed Nicols on the incident side and emission side of colored light. The same applies to the other liquid crystal light valves 122 and 123.

  As described above, in the liquid crystal devices 71, 72, 73 applied to the liquid crystal light valves 121, 122, 123, both the first convex portion 14 and the second convex portion 16 are in the Z (+) direction. The light L2 bent in the direction in which the angle is further increased is taken by the projection lens 117 (projection optical system) and is not projected onto the screen 130 (it is difficult to be recognized as a display).

  The liquid crystal devices 71, 72, and 73 according to the above-described embodiments have higher display brightness and display contrast than the liquid crystal device that does not include the microlens array substrate 10, and provide a bright and high-quality display. Therefore, even in the projector 100 on which the liquid crystal devices 71, 72, and 73 are mounted, a bright and high-quality display is provided.

The present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the scope or spirit of the invention that can be read from the claims and the entire specification. An optical unit and an electronic device in which a liquid crystal device is mounted are also included in the technical scope of the present invention.
Various modifications other than the above embodiment are conceivable. Hereinafter, a modification will be described.

(Modification 1)
In the liquid crystal devices 71, 72, and 73, the microlens array substrate 10 that collects light is provided on the counter substrate 30 side, light is incident on the counter substrate 30 side, and light is emitted from the element substrate 20 side. However, it is not limited to this. For example, the microlens array substrate 10 that collects light may be provided on the element substrate 20 side, light may be incident on the element substrate 20 side, and light may be emitted from the counter substrate 30 side.

(Modification 2)
In the liquid crystal device 71 according to the first embodiment, the first lens layer 13 is made of SiON (high refractive index material), and the second lens layer 15 is made of SiO ₂ (low refractive index material). It is not limited. For example, the first lens layer 13 and the second lens layer 15 may be made of the same material (SiON). When the first lens layer 13 and the second lens layer 15 are made of the same material (SiON), the first lens layer 13 and the second lens layer 15 are made different from the case where the first lens layer 13 and the second lens layer 15 are made of different materials. The total value of the layer thicknesses of the two lens layers 15 can be reduced, and the first lens layer 13 and the second lens layer 15 can be thinned. When the first lens layer 13 and the second lens layer 15 are thinned, the stress of the first lens layer 13 and the second lens layer 15 is reduced, and the adverse effect of the increased stress can be reduced.

  When the first lens layer 13 and the second lens layer 15 are made of the same material (SiON), the N content of SiON constituting the transparent film 7 is set to the first lens layer 13 and the second lens layer 15. It is necessary to increase the refractive index of SiON constituting the transparent film 7 to be higher than the refractive index of SiON constituting the first lens layer 13 and the second lens layer 15.

(Modification 3)
In the liquid crystal device 73 according to the third embodiment, the transparent film 17 is made of SiO ₂ (low refractive index material) and the transparent film 7 is made of SiON (high refractive index material), but is not limited thereto. For example, the transparent film 17 and the transparent film 7 may be made of the same material (SiON). When the transparent film 17 and the transparent film 7 are made of the same material (SiON), the total value of the film thickness of the transparent film 17 and the transparent film 7 is made smaller than when the transparent film 17 and the transparent film 7 are made of different materials. In addition, the transparent film 17 and the transparent film 7 can be thinned. When the transparent film 17 and the transparent film 7 are thinned, the stress of the transparent film 17 and the transparent film 7 is reduced, and the adverse effect of the large stress can be reduced.

  When the transparent film 17 and the transparent film 7 are made of the same material (SiON), the N content of SiON constituting the first lens layer 13 is the N content of SiON constituting the transparent film 17 and the transparent film 7. It is necessary to make the refractive index of SiON constituting the first lens layer 13 higher than the refractive index of SiON constituting the transparent film 17 and the transparent film 7.

(Modification 4)
The electronic apparatus to which the liquid crystal devices 71, 72, and 73 according to the present embodiment are applied is not limited to the projector (projection display device) 100 according to the fourth embodiment. For example, in addition to the projector (projection display device) 100, a projection HUD (head-up display), a direct-view HMD (head-mounted display), an electronic book, a personal computer, a digital still camera, a liquid crystal television, and a viewfinder type Alternatively, the liquid crystal devices 71, 72, and 73 according to the present embodiment can be applied to monitor direct-view video recorders, car navigation systems, information terminal devices such as POS, and electronic devices such as electronic notebooks.

  71, 72, 73 ... liquid crystal device, 2 ... scanning line, 3 ... data line, 4 ... capacitance line, 5 ... storage capacitor, 10 ... microlens array substrate, 11 ... substrate, 11a ... upper surface of substrate, 11b ... substrate Lower surface, 12 ... concave portion, 13 ... first lens layer, 13a ... upper surface of first lens layer, 13b ... lower surface of first lens layer, 14 ... first convex portion, 14a ... flat portion, 15 ... second lens layer 15a ... upper surface of the second lens layer, 15b ... lower surface of the second lens layer, 16 ... second convex portion, 16a ... flat portion, 7 ... transparent film, 7a ... upper surface of the transparent film, 7b ... lower surface of the transparent film , 8 ... recess, 8 a ... flat part, 17 ... transparent film, 17 a ... upper surface of the transparent film, 17 b ... lower surface of the transparent film, 18 ... recessed part, 18 a ... flat part, 20 ... element substrate, 21 ... substrate, 22 ... light shielding Layer, 23 ... insulating layer, 24 ... TFT, 25 ... insulating layer, 26 ... light shielding layer, 27 ... insulating 28 ... Pixel electrode, 29 ... Alignment film, 30 ... Opposite substrate, 32 ... Light shielding layer, 33 ... Protective layer, 34 ... Common electrode, 35 ... Alignment film, 40 ... Liquid crystal layer, V1 ... Light shielding part, V2 ... Opening part .

Claims (4)

A first lens layer comprising a second surface covering the first surface of the transparent substrate, and a third surface having a first convex portion disposed on the opposite side of the second surface;
A first transparent film covering the third surface and having a flat surface disposed on the opposite side of the surface in contact with the third surface;
A second transparent film including a surface that covers the flat surface and includes a concave portion corresponding to the first convex portion disposed on the opposite side of the surface in contact with the flat surface;
A second lens that includes a fourth surface that covers the surface on which the concave portion is provided and has a second convex portion inside the concave portion, and a flat fifth surface that is disposed on the opposite side of the fourth surface. Layers,
Including
The refractive index of the first lens layer is higher than the refractive index of the transparent substrate,
The refractive index of the first transparent film is lower than the refractive index of the first lens layer,
Refractive index of the second transparent film is high remote I refractive index of the first transparent film,
The refractive index of the second lens layer, a microlens array board which being lower than the refractive index of the second transparent film. An electro-optical device having an element substrate having a pixel electrode, a counter substrate having a common electrode, and an electro-optical material sandwiched between the element substrate and the counter substrate,
The electro-optical device, wherein the element substrate or the counter substrate includes the microlens array substrate according to claim 1 . The counter substrate includes the microlens array substrate according to claim 1 ,
The electro-optical device according to claim 8, wherein the element substrate includes a light shielding unit that blocks light in a direction from the counter substrate toward the element substrate. An electronic apparatus characterized by comprising an electro-optical device according to claim 2 or 3.

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