JP2015200766A - Microlens array substrate, method for manufacturing microlens array substrate, liquid crystal device, and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microlens array substrate having microlenses capable of reducing irregularity in brightness caused by distribution of incident angles of incident light, a method for manufacturing a microlens array substrate, a liquid crystal device including the microlens array substrate, and electronic equipment.SOLUTION: A microlens array substrate 10A includes a microlens ML1 disposed in each of a plurality of pixels on a substrate body 11. The microlens ML1 includes: a flat portion 12a that opposes to a surface of the substrate body 11 where incident light enters; a first lens portion 12b that is disposed along an arc portion 12ab of the flat portion 12a and condenses the incident light toward the center of the pixel; and a second lens portion 12c that is disposed along a straight line portion 12ac of the flat portion 12a and refracts the incident light into a specific direction relative to the pixel.

Description

  The present invention relates to a microlens array substrate, a method for manufacturing the microlens array substrate, a liquid crystal device including the microlens array substrate, and an electronic apparatus.

  As a liquid crystal device, a transmissive liquid crystal device applied to a light valve (light modulation means) of a projector (projection display device) is known. In such a transmissive liquid crystal device, a configuration is proposed in which a microlens (ML) is provided as a condensing unit on the light incident side of the pixel in order to enable bright display by effectively using light emitted from the light source. Has been.

For example, in Patent Document 1, each pixel electrode or a group of pixel electrodes corresponding to a plurality of color lights is arranged to face each other, and each has a plurality of lens surfaces or divided lens surfaces having different curvatures. A liquid crystal display element including a plurality of microlenses and a light modulation unit that modulates incident color light according to an image signal applied to a pixel electrode is disclosed.
According to the liquid crystal display element of Patent Document 1, each microlens is associated with one pixel electrode or a group of pixel electrodes associated with a plurality of color lights, that is, compared with a case where one microlens is disposed for each substantial display pixel. Therefore, the micro lens array (MLA) can be thinned. Thereby, the thermal stress received by the MLA is reduced, the gap unevenness of the liquid crystal layer in the liquid crystal display element is reduced, and high-quality image display can be performed.

Patent Document 2 discloses a VA (Vertical Alignment) system in which liquid crystal molecules are aligned with a pretilt angle of less than 90 degrees with respect to the substrate surface in the initial alignment state, and the azimuth angle of the pretilt is A liquid crystal device is disclosed that includes optical axis deflection means that are substantially aligned and tilt light incident from the normal direction of the substrate toward the azimuth side of the pretilt of liquid crystal molecules. Further, as the optical axis deflecting means, a condensing lens structure (microlens) that is asymmetric with respect to the substrate normal is cited.
According to the liquid crystal device of Patent Document 2, it is possible to realize a higher contrast than the conventional one by suppressing a decrease in transmittance or light leakage in the initial alignment state.

Japanese Patent Laid-Open No. 2000-193928 JP 2006-184673 A

  When the liquid crystal display element of Patent Document 1 or the liquid crystal device of Patent Document 2 is used as a light valve (light modulation means), the light utilization efficiency is to allow light from the light source to enter the microlens from a certain direction. Etc. are preferable. However, in practice, it is difficult to make the angle of light incident on the microlens for each pixel constant, and there is a distribution of incident angles of incident light in a display area where a plurality of pixels are arranged. In particular, the incident angle of the incident light may be larger at the corner of the display area away from the optical axis connecting the light source and the light valve (light modulation means) than at the center of the display area. If it does so, even if it has the microlens shown by the said patent document 1 or the said patent document 2, there existed a subject that the nonuniformity of brightness might be conspicuous in a display area. Note that uneven brightness is paraphrased as uneven light transmittance in bright display and uneven contrast in dark display.

  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] The microlens array substrate according to this application example is a microlens array substrate having microlenses arranged for each of a plurality of pixels on the substrate, and among the microlenses arranged for each of the plurality of pixels At least some of the microlenses are positioned around the flat portion facing the surface of the substrate on the side where incident light is incident, and around the flat portion, and collect the incident light toward the center of the pixel. It includes a first lens unit that emits light and a second lens unit that refracts the incident light in a specific direction with respect to the pixel.

  According to this application example, even if the incident light incident on the surface of the substrate has a distribution of incident angles, the distribution of the incident angles can be achieved by arranging the second lens unit corresponding to the distribution of the incident angles. It is possible to provide a microlens array substrate that can reduce unevenness in brightness due to the above.

In the microlens array substrate according to the application example, each of the microlenses arranged for each of the plurality of pixels includes the flat portion, the first lens portion, and the second lens portion. Is preferred.
According to this configuration, it is possible to reduce uneven brightness by using all the microlenses.

In the microlens array substrate according to the application example described above, in the region where the pixels are arranged, a first region including a corner portion of the region includes the flat portion, the first lens portion, and the second portion. A first microlens including the lens portion, and a second microlens including the flat portion and the first lens portion in a second region of the region other than the first region. A lens may be arranged.
According to this configuration, the flat portion, the first lens portion, and the second lens portion are provided in the first region including the corner portion where the incident angle of incident light is likely to be larger than that of the second region. Since the included microlens is arranged, uneven brightness in the corners can be effectively reduced. Further, since the second microlens that places importance on the light condensing property is arranged in the second region, the brightness can be improved as compared with the case where the first microlens is arranged in all the pixels. it can.

In the microlens array substrate according to the application example, the flat portion includes an arc portion serving as a boundary with the first lens portion and a linear portion serving as a boundary with the second lens portion. Features.
According to this configuration, the second lens unit in contact with the linear part of the flat part refracts incident light in a direction intersecting the linear part in plan view. Therefore, if the second lens unit is arranged so that the first direction in which the unevenness of brightness occurs and the extending direction of the straight line part are parallel, the unevenness in brightness in the first direction can be reduced. Can do.

  [Application Example] A method of manufacturing a microlens array substrate according to this application example is a method of manufacturing a microlens array substrate having a microlens arranged for each of a plurality of pixels on the substrate, wherein one surface of the substrate is formed. A step of forming a mask layer to cover, a step of patterning the mask layer to form a mask pattern having an opening, a step of isotropically etching the substrate through the opening, and forming a lens surface; Removing the mask pattern, forming a lens layer precursor that covers one surface of the substrate and filling the lens surface, and forming a lens layer by flattening the surface of the lens layer precursor. And a step of forming an optical path length adjustment layer covering the lens layer, and in the step of forming the mask pattern, an arc portion and a straight portion are used. And forming a that the opening.

  According to this application example, the opening in the mask pattern is configured by the arc portion and the straight portion. Therefore, when isotropic etching is performed on the substrate, a flat lens surface is formed by etching in a region corresponding to the opening in the thickness direction of the substrate, and a lens surface having a curved surface with the arc portion or straight portion of the opening as a boundary. Etching is formed. By filling the lens surface with a lens layer, a flat portion having a flat lens surface with respect to one surface of the substrate, a first lens portion having a curved surface extending along the arc portion, and a straight portion A microlens including a second lens portion having a curved surface extending along the surface can be formed. Incident light incident on the flat portion travels substantially straight. Incident light incident on the first lens unit is collected at one point. Incident light that has entered the second lens portion is refracted in a direction that intersects the straight portion. Therefore, if the second lens portion is etched by forming a mask pattern having an opening so that the first direction in which unevenness of brightness occurs and the extending direction of the straight line portion are parallel to each other, It is possible to manufacture a microlens array substrate capable of reducing unevenness in brightness in one direction.

In the method of manufacturing the microlens array substrate according to the application example, in the step of forming the mask pattern, the arc portion and the first region including the corner portion of the region in the region where the pixels are arranged A first opening formed of a straight line portion is formed, and a circular second opening is formed in a second region other than the first region in the region.
According to this method, the flat region, the first lens portion, and the second lens portion are included in the first region including the corner portion where the incident angle of incident light is likely to be larger than the other portions. Since the microlens is formed, uneven brightness at the corners can be effectively reduced.

  [Application Example] A liquid crystal device according to this application example includes a pair of substrates and a liquid crystal layer sandwiched between the pair of substrates, and one of the pair of substrates is provided for each of a plurality of pixels. A liquid crystal device having a microlens arranged, wherein at least some of the microlenses arranged for each of the plurality of pixels have a surface with respect to the surface of the one substrate on which incident light is incident. And a first lens part that is positioned around the flat part and collects the incident light toward the center of the pixel, and the incident light is directed in a specific direction with respect to the pixel. And a second lens portion to be refracted.

  According to this application example, even if the incident light incident on the surface of one of the substrates has an incident angle distribution, the second lens unit is arranged in accordance with the incident angle distribution, so that the incident angle is increased. Accordingly, it is possible to provide a liquid crystal device capable of reducing unevenness in brightness due to the distribution of.

In the liquid crystal device according to the application example, each of the microlenses arranged for each of the plurality of pixels preferably includes the flat portion, the first lens portion, and the second lens portion. .
According to this configuration, it is possible to provide a liquid crystal device that can reduce unevenness of brightness over the entire display area by using all the microlenses.

In the liquid crystal device according to the application example, in the display region where the pixels are arranged, a first region including a corner of the display region includes the flat portion, the first lens portion, and the second lens portion. A first microlens including the lens portion, and a second region including the flat portion and the first lens portion in the second region other than the first region in the display region. Microlenses may be arranged.
According to this configuration, the flat portion, the first lens portion, and the second lens portion are provided in the first region including the corner portion where the incident angle of incident light is likely to be larger than that of the second region. Since the microlens including the liquid crystal device is disposed, a liquid crystal device capable of effectively reducing uneven brightness at the corners can be provided.

In the liquid crystal device according to the application example, the flat portion includes an arc portion serving as a boundary with the first lens portion and a linear portion serving as a boundary with the second lens portion, and the pixel includes The microlens is arranged so that the long axis direction of the liquid crystal molecules in the liquid crystal layer and the straight line portion in the bright display are parallel to each other, and the orientation of the liquid crystal molecules in the liquid crystal layer is controlled. It is characterized by that.
According to this configuration, it is possible to provide a liquid crystal device that can reduce uneven brightness in bright display.

In the liquid crystal device according to the application example, the flat portion includes an arc portion serving as a boundary with the first lens portion and a linear portion serving as a boundary with the second lens portion, and the pixel includes The microlens is arranged so that the long axis direction of the liquid crystal molecules in the liquid crystal layer at the time of dark display and the linear portion are orthogonal to each other, and the orientation of the liquid crystal molecules in the liquid crystal layer is controlled. It is characterized by.
According to this configuration, it is possible to provide a liquid crystal device capable of reducing uneven brightness in dark display, that is, uneven contrast.

In the liquid crystal device according to the application example, the flat portion includes an arc portion serving as a boundary with the first lens portion and a linear portion serving as a boundary with the second lens portion, and the pixel includes The major axis direction of the liquid crystal molecules in the liquid crystal layer at the time of bright display and the linear portion are parallel, and the major axis direction of the liquid crystal molecules in the liquid crystal layer at the time of dark display and the linear portion are The microlenses are arranged so as to be orthogonal to each other, and the orientation of liquid crystal molecules in the liquid crystal layer is controlled.
According to this configuration, it is possible to provide a liquid crystal device that can reduce uneven brightness in bright display and uneven contrast in dark display.

In the liquid crystal device according to the application example described above, the pixel has a pixel opening section partitioned by a light shielding film, and the center of gravity of the pixel opening section and the center defined by the radius of the arc section match in plan view. It is preferable to do it.
According to this configuration, it is possible to provide a liquid crystal device in which incident light collected by the microlens efficiently passes through the pixel opening.

In the liquid crystal device according to the application example described above, it is preferable that the linear portion of the flat portion passes through the center of gravity of the pixel opening in a plan view.
According to this configuration, since the region where the first lens portion extending along the arc portion of the flat portion is formed can be maximized, the light condensing ability by the microlens can be maximized. That is, it is possible to provide a liquid crystal device that can reduce unevenness of brightness and can display brighter.

[Application Example] An electronic apparatus according to this application example includes the liquid crystal device according to the application example described above.
An electronic device including a liquid crystal device with reduced brightness unevenness and excellent display quality can be provided.

1 is a schematic plan view showing a configuration of a liquid crystal device according to a 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 showing the structure of the liquid crystal device along the line A-A ′ of FIG. 1. (A) is a schematic sectional drawing which shows the orientation state of the liquid crystal molecule in a liquid-crystal layer, (b) is a schematic plan view which shows the azimuth in the orientation process of a liquid crystal molecule. (A) is a schematic diagram showing the light condensing state with respect to the liquid crystal panel, (b) is a schematic plan view showing the incident direction of light at the corner of the display region, and (c) is a diagram showing the incident light and the orientation of the liquid crystal molecules. The schematic sectional drawing which shows a relationship. (A) is a schematic plan view showing a microlens, (b) is a schematic plan view showing a microlens array substrate focusing on the brightness of bright display, and (c) is a schematic cross section showing a liquid crystal panel including the microlens array substrate. Figure. FIG. 7A is a schematic cross-sectional view showing the structure of a microlens array substrate taken along line B-B ′ in FIG. 6A, and FIG. 7B is a perspective view showing the microlens. (A) is a schematic plan view explaining the condensing function of a microlens, (b) is a schematic plan view which shows the positional relationship of the microlens and pixel opening part in a pixel. FIG. 4A is a schematic plan view showing a microlens array substrate that emphasizes contrast for dark display, and FIG. 4B is a schematic cross-sectional view of a liquid crystal panel that includes the microlens array substrate that emphasizes contrast for dark display. The flowchart which shows the manufacturing method of a micro lens array board | substrate. (A)-(d) is a schematic sectional drawing which shows the manufacturing method of a micro lens array board | substrate. (E)-(h) is a schematic sectional drawing which shows the manufacturing method of a micro lens array board | substrate. The schematic plan view which shows a mask pattern. (A)-(c) is the schematic for demonstrating arrangement | positioning of the electrode in the liquid crystal device of 2nd Embodiment, the alignment processing method of a liquid crystal molecule, and the drive method. (A) is a schematic plan view showing the relationship between the orientation of liquid crystal molecules and the arrangement of microlenses during dark display in the liquid crystal device of the second embodiment, and (b) is a bright display in the liquid crystal device of the second embodiment. FIG. 5 is a schematic plan view showing the relationship between the orientation of liquid crystal molecules and the arrangement of microlenses. Schematic which shows the structure of the projection type display apparatus as an electronic device. (A) is a schematic plan view which shows microlens array board | substrate 10D of the modification 1, (b) is a schematic plan view which shows the structure of microlens ML2. (A) is a schematic plan view which shows the structure of microlens ML3 of the modification 2, (b) is a schematic sectional drawing of the microlens array board | substrate 10E of the modification 2 cut | disconnected by the C-C 'line | wire of (a). FIG. 10 is a schematic cross-sectional view showing the structure of a microlens array substrate 10F of Modification 3. FIG. 10 is a schematic plan view illustrating an example of a pixel opening according to Modification 4.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. Note that the drawings to be used are appropriately enlarged or reduced so that the part to be described can be recognized.

  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)
<Liquid crystal device>
As an example of the liquid crystal device according to the present embodiment, an active matrix type liquid crystal device including a thin film transistor (TFT) as a pixel switching element will be described. This liquid crystal device can be suitably used, for example, as a light modulation element (liquid crystal light valve) of a projection display device (liquid crystal projector) described later.

  First, the liquid crystal device of this embodiment will be described with reference to FIGS. 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 the electrical configuration of the liquid crystal device according to the first embodiment, and FIG. 3 is an AA of FIG. 4 'is a schematic cross-sectional view showing the structure of the liquid crystal device along the line, FIG. 4 (a) is a schematic cross-sectional view showing the alignment state of the liquid crystal molecules in the liquid crystal layer, and FIG. 4 (b) is an azimuth angle in the alignment treatment of the liquid crystal molecules. It is a schematic plan view shown.

  As shown in FIGS. 1 and 3, the liquid crystal device 100 according to the present embodiment includes an element substrate 20 and a counter substrate 30 that are disposed to face each other, and a liquid crystal layer 40 that is disposed between the element substrate 20 and the counter substrate 30. have. As shown in FIG. 1, the element substrate 20 is slightly larger than the counter substrate 30, and the two substrates are bonded together via a sealing material 42 arranged in a frame shape along the outer 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.

  A display region E including a plurality of pixels P arranged in a matrix is provided inside the sealing material 42 arranged in a frame shape. Further, a parting portion 14 is provided between the sealing material 42 and the display area E so as to surround the display area E. The parting portion 14 is defined by a first light shielding layer 22, a second light shielding layer 26, and a light shielding film 32 made of a light shielding metal or metal compound described later. Note that the display area E may include dummy pixels arranged so as to surround the plurality of pixels P in addition to the plurality of pixels P contributing to display. Further, as will be described in detail later, a microlens ML1 as a light condensing unit and a light shielding film 32 arranged corresponding to each of the plurality of pixels P in the display region E are provided on the counter substrate 30 (FIG. 3). reference).

  The element substrate 20 is provided with a terminal portion in which a plurality of external connection terminals 54 are arranged. A data line driving circuit 51 is provided between the first side portion along the terminal portion of the element substrate 20 and the sealing material 42. In addition, an inspection circuit 53 is provided between the sealing material 42 and the display area E along the second side facing the first side. Further, a scanning line driving circuit 52 is provided between the seal material 42 and the display area E along the third and fourth sides that are orthogonal to the first 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 on the second side and the inspection circuit 53. 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.

  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 first side. In the following description, the direction along the first side is defined as the X direction, and the direction along the third side is defined as the Y direction. The direction along the line A-A ′ in FIG. 1 is the X direction. A direction orthogonal to the X direction and the Y direction and going from the element substrate 20 toward the counter substrate 30 is defined as a Z direction. In the present specification, viewing from the surface 11b (see FIG. 3) of the counter substrate 30 along the Z direction is referred to as “plan view”.

  Next, the electrical configuration of the liquid crystal device 100 will be described with reference to FIG. The liquid crystal device 100 includes a plurality of scanning lines 2 and a plurality of data lines 3 as signal wirings that are insulated and orthogonal to each other at least in the display region E, and capacitance lines 4 arranged in parallel along the scanning lines 2. . The direction in which the scanning line 2 extends is the X direction, and the direction in which the data line 3 extends is the Y direction.

  A pixel electrode 28, a TFT 24, and a storage capacitor 5 are provided in a region divided by the scanning line 2, the data line 3, the capacitor line 4, and these signal lines, and these constitute a pixel circuit of the pixel P. doing.

  The scanning line 2 is electrically connected to the gate of the TFT 24, and the data line 3 is electrically connected to the source of the TFT 24. The pixel electrode 28 is electrically connected to the drain of the TFT 24.

  The data line 3 is connected to a data line driving circuit 51 (see FIG. 1), and supplies image signals D1, D2,..., Dn supplied from the data line driving circuit 51 to the pixels P. The scanning lines 2 are connected to a scanning line driving circuit 52 (see FIG. 1), and supply scanning signals G1, G2,..., Gm supplied from the scanning line driving circuit 52 to the pixels P.

  The image signals D1 to Dn supplied from the data line driving circuit 51 to the data lines 3 may be supplied line-sequentially in this order, or may be supplied for each of a plurality of adjacent data lines 3 for each group. Good. The scanning line driving circuit 52 supplies the scanning signals G1 to Gm to the scanning line 2 in a pulse-sequential manner at a predetermined timing.

  In the liquid crystal device 100, the TFT 24, which is a switching element, is turned on for a certain period by the input of the scanning signals G1 to Gm, so that the image signals D1 to Dn supplied from the data line 3 are at the predetermined timing. It is the structure written in. A predetermined level of the image signals D1 to Dn written to the liquid crystal layer 40 via the pixel electrode 28 is between the pixel electrode 28 and the common electrode 34 (see FIG. 3) disposed opposite to the liquid crystal layer 40. Is held for a certain period. The frequency of the image signals D1 to Dn is 60 Hz, for example.

  In order to prevent the held image signals D1 to Dn from leaking, the storage capacitor 5 is connected in parallel with the liquid crystal capacitor formed between the pixel electrode 28 and the common electrode 34. The storage capacitor 5 is provided between the drain of the TFT 24 and the capacitor line 4.

  The data line 3 is connected to the inspection circuit 53 shown in FIG. 1, and the operation defect of the liquid crystal device 100 can be confirmed by detecting the image signal in the manufacturing process of the liquid crystal device 100. Although not shown in the equivalent circuit of FIG.

  The peripheral circuit for driving and controlling the pixel circuit in the present embodiment includes a data line driving circuit 51, a scanning line driving circuit 52, and an inspection circuit 53. The peripheral circuit includes a sampling circuit that samples the image signal and supplies it to the data line 3, and a precharge circuit that supplies a precharge signal of a predetermined voltage level to the data line 3 prior to the image signal. Also good.

  Next, the structure of the liquid crystal device 100 will be described with reference to FIG. As shown in FIG. 3, the element substrate 20 includes a translucent substrate body 21, a first light shielding layer 22, an insulating film 23, a TFT 24, and a first interlayer insulating film provided on the substrate body 21. 25, a second light shielding layer 26, a second interlayer insulating film 27, a pixel electrode 28, and an alignment film 29. The substrate body 21 is made of a light transmissive material such as glass or quartz.

The first light shielding layer 22 and the second light shielding layer 26 are made of, for example, metals such as Al (aluminum), Ti (titanium), Cr (chromium), W (tungsten), Ta (tantalum), and Mo (molybdenum). A metal simple substance including at least one, an alloy, a metal silicide, a polysilicide, a nitride, or a laminate thereof can be used, and has both light shielding properties and conductivity.
The first light shielding layer 22 is formed in a lattice shape so as to overlap the upper second light shielding layer 26 in plan view, and is arranged so as to sandwich the TFT 24 in the thickness direction (Z direction) of the element substrate 20. Has been. Incidence of light to the TFT 24 is suppressed by the first light shielding layer 22 and the second light shielding layer 26. A region surrounded by the first light shielding layer 22 and the second light shielding layer 26 (inside the opening portions 22a and 26a) is an opening region (pixel opening portion) through which light passes through the element substrate 20.

The insulating film 23 is provided so as to cover the substrate body 21 and the first light shielding layer 22. The insulating film 23 is made of an inorganic material such as SiO ₂ . The TFT 24 is provided on the insulating film 23. Although not shown, the TFT 24 has a semiconductor layer, a gate electrode, a source electrode, and a drain electrode.

The gate electrode is disposed opposite to a region overlapping the channel region of the semiconductor layer in plan view on the element substrate 20 via a part (gate insulating film) of the first interlayer insulating film 25.
The first light shielding layer 22 is patterned so that a part thereof functions as the scanning line 2 (see FIG. 2). The gate electrode is electrically connected to the scanning line 2 disposed on the lower layer side through a contact hole that penetrates the gate insulating film and the insulating film 23.

The first interlayer insulating film 25 is provided so as to cover the insulating film 23 and the TFT 24. The first interlayer insulating film 25 is made of an inorganic material such as SiO ₂ , for example. The first interlayer insulating film 25 includes a gate insulating film that insulates between the semiconductor layer of the TFT 24 and the gate electrode. The first interlayer insulating film 25 alleviates surface irregularities caused by the TFT 24.
A second light shielding layer 26 is provided on the first interlayer insulating film 25. The second light shielding layer 26 is patterned so as to function as any of the electrodes of the data line 3, the capacitor line 4, or the storage capacitor 5 that is electrically connected to the TFT 24. A second interlayer insulating film 27 made of an inorganic material is provided so as to cover the first interlayer insulating film 25 and the second light shielding layer 26.

  The pixel electrode 28 is made of a transparent conductive film such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide), and is provided on the second interlayer insulating film 27 corresponding to the pixel P. The pixel electrode 28 is disposed in a region overlapping the opening 22 a of the first light shielding layer 22 and the opening 26 a of the second light shielding layer 26 in plan view. The outer edge of the pixel electrode 28 is disposed so as to overlap the second light shielding layer 26 in plan view.

  The alignment film 29 covering the pixel electrode 28 is, for example, an organic resin material such as polyimide capable of substantially horizontally aligning liquid crystal (liquid crystal molecules) having positive dielectric anisotropy, or liquid crystal having negative dielectric anisotropy. For example, an inorganic material such as silicon oxide that can substantially align (liquid crystal molecules) can be used.

  The liquid crystal constituting the liquid crystal layer 40 modulates the light incident on the liquid crystal layer 40 by changing the alignment state of the liquid crystal molecules according to the voltage level applied between the pixel electrode 28 and the common electrode 34, and the gradation Enable display. 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 according to 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 100 as a whole. In the present embodiment, the liquid crystal device 100 is configured on the assumption that light enters from the counter substrate 30 side, passes through the liquid crystal layer 40, and is emitted from the element substrate 20 side.

  The counter substrate 30 includes a microlens array substrate 10, a light shielding film 32, a planarization layer 33 that covers the light shielding film 32, a common electrode 34, and an alignment film 35. The microlens array substrate 10 includes a translucent substrate body 11, a lens layer 13 including a microlens ML <b> 1 arranged corresponding to each of the plurality of pixels P, and an optical path length adjustment layer 31. Note that the microlens array substrate 10 may not include the optical path length adjustment layer 31. Or it is good also as a structure containing the light shielding film 32, the planarization layer 33, and the common electrode 34. FIG. Further, the light shielding film 32 may be disposed between the lens layer 13 and the optical path length adjusting layer 31. According to this, the planarization layer 33 can be eliminated.

  The substrate body 11 has a plurality of recesses 12 formed on the surface 11a on the liquid crystal layer 40 side opposite to the surface 11b. Each recess 12 is provided corresponding to each pixel P. The bottom part of the recessed part 12 is formed in a flat state, and comprises the flat part 12a among the lens surfaces in the microlens ML1. Hereinafter, the recess 12 may be referred to as the lens surface 12. The substrate body 11 is made of a light transmissive material such as glass or quartz. Further, the surface 11a of the substrate body 11 corresponds to one surface of the substrate in the present invention.

The lens layer 13 includes a plurality of microlenses ML <b> 1 formed by filling a plurality of concave portions 12 formed corresponding to the plurality of pixels P on the surface 11 a side of the substrate body 11. The lens layer 13 is made of an inorganic lens material that has optical transparency and a refractive index n higher than that of the substrate body 11. For example, if the substrate body 11 is a quartz substrate having a refractive index n of approximately 1.46, the lens material constituting the lens layer 13 is SiON (refractive index n = 1.50 to 1.70), Al _2. And O ₃ (refractive index n = 1.76). The refractive index n depends on the wavelength of light transmitted through the substrate body 11 and the lens layer 13.

  Although a detailed method of forming the lens layer 13 will be described later, the concave portion 12 is formed by selectively etching one surface 11a of the substrate body 11, and the flat portion 12a is formed by filling the concave portion 12 with the lens material described above. The microlens ML1 is formed. In addition, a microlens array MLA is configured by the plurality of microlenses ML1.

  An optical path length adjustment layer 31 is provided so as to cover the surface 13a of the lens layer 13. The optical path length adjusting layer 31 is light transmissive, and is made of, for example, an inorganic material having substantially the same refractive index n as that of the substrate body 11. The optical path length adjusting layer 31 is provided so as to flatten the surface of the microlens array substrate 10 facing the liquid crystal layer 40 and to focus the light collected by the microlens ML1 at a desired position. Yes. Therefore, the layer thickness of the optical path length adjustment layer 31 is appropriately set based on optical conditions such as the focal length of the microlens ML1 corresponding to the wavelength of light.

  A light shielding film 32 is provided on the flat surface of the optical path length adjusting layer 31 that covers the side of the lens layer 13 opposite to the microlens ML1. The light shielding film 32 is provided in a peripheral region surrounding the display region E where the plurality of microlenses ML1 are provided, and constitutes the parting section 14.

  The light-shielding film 32 is made of, for example, a light-shielding material such as Al (aluminum), Mo (molybdenum), W (tungsten), Ti (titanium), TiN (titanium nitride), or Cr (chromium), or these materials. It can be composed of a laminate of at least two materials selected from the inside. Although detailed illustration is omitted in FIG. 3, in the present embodiment, the light shielding film 32 includes two layers of Al (aluminum) and TiN (titanium nitride) that are sequentially stacked from the surface side of the optical path length adjustment layer 31. It has a structure.

  A common electrode 34 is provided so as to cover the planarization layer 33. The common electrode 34 is a counter electrode that is formed across a plurality of pixels P and faces the pixel electrode 28 with the liquid crystal layer 40 interposed therebetween. As the common electrode 34, for example, a transparent conductive film such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide) is used. Since the common electrode 34 is disposed to face the plurality of pixel electrodes 28 with the liquid crystal layer 40 interposed therebetween, the surface of the common electrode 34 must be flat in order to realize desired optical characteristics for each pixel P. Is preferred. The common electrode 34 is electrically connected to the wiring connected to the external connection terminal 54 of the element substrate 20 through the vertical conduction portion 56 provided at the corner of the counter substrate 30 (see FIG. 1).

  An alignment film 35 is provided to cover the common electrode 34. Similar to the alignment film 29 on the element substrate 20 side, the alignment film 35 is formed using an organic resin material such as polyimide or an inorganic material such as silicon oxide. As described above, the material selection and alignment processing methods of the alignment films 29 and 35 depend on the selection of liquid crystal based on the optical design of the liquid crystal device 100 and the display mode.

  In the liquid crystal device 100, light enters from the side of the counter substrate 30 (the surface 11b of the substrate body 11) provided with the microlens ML1, and is collected for each pixel P by the microlens ML1. For example, of the light incident on the microlens ML1 from the surface 11b side of the substrate body 11, the incident light L1 incident along the optical axis passing through the planar center of the pixel P passes through the flat portion 12a of the microlens ML1. As it goes straight, it passes through the liquid crystal layer 40 and is emitted to the element substrate 20 side.

  Incident light L2 that has entered the periphery of the flat portion 12a of the microlens ML1 outside the incident light L1 is refracted toward the planar center of the pixel P due to the difference in refractive index n between the substrate body 11 and the lens layer 13. To do. If the incident light L2 goes straight as it is, it may be slightly refracted by passing through the liquid crystal layer 40 or the element substrate 20, and may be incident on the second light shielding layer 26 (or the first light shielding layer 22) to be shielded. is there.

  In the liquid crystal device 100, the incident light L2, which may be shielded by the second light shielding layer 26 (or the first light shielding layer 22) in this way, passes through the liquid crystal layer 40 by the condensing action of the microlens ML1. 2 The light can enter the opening 26 a of the light shielding layer 26 (or the opening 22 a of the first light shielding layer 22). 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. In this embodiment, since light is incident from the counter substrate 30 side, the microlens ML1 is provided on the counter substrate 30 side. However, light is incident from the element substrate 20 side, and the microlens ML1 is disposed on the element substrate 20 side. It is good also as a structure to provide.

  Next, the alignment state of the liquid crystal molecules in the liquid crystal device 100 will be described with reference to FIG. In FIG. 4, in explaining the alignment state of the liquid crystal molecules, the electrical configuration of the TFT 24 and the like in the element substrate 20 and the configuration of the microlens ML1 and the like in the counter substrate 30 are not shown.

  The liquid crystal layer 40 in the liquid crystal device 100 of the present embodiment employs, for example, a liquid crystal molecule alignment method called a VA (Vertical Alignment) method. Specifically, as shown in FIG. 4A, the orientation obtained by obliquely depositing silicon oxide on the surface of the pixel electrode 28 in the liquid crystal device 100 by a vacuum deposition method which is an example of a vapor phase growth method. A film 29 is formed. By oblique deposition, a silicon oxide crystal grows in a columnar shape toward the deposition direction on the substrate surface. This columnar crystal is referred to as column 29a. The alignment film 29 is an aggregate of such columns 29a. Similarly, the alignment film 35 covering the surface of the common electrode 34 in the liquid crystal device 100 is also an assembly of columns 35a.

On the surfaces of the alignment films 29 and 35, the liquid crystal molecules LC having negative dielectric anisotropy have a pretilt angle (tilt angle) θp of about 3 to 5 degrees with respect to the normal line of the substrate surface. Are approximately vertically aligned. In addition, the pretilt direction, that is, the tilt direction for tilting the liquid crystal molecules LC is the same as the planar deposition direction of the oblique deposition in the alignment films 29 and 35.
Specifically, as shown in FIG. 4B, the tilt direction of the pretilt of the liquid crystal molecules LC in the display region E is set so that the azimuth angle θa made with the Y direction is 45 degrees. An arrow direction indicated by a broken line is a direction of oblique deposition with respect to the element substrate 20 and is a direction from the upper right to the lower left. On the other hand, the arrow direction indicated by the solid line is the direction of oblique deposition with respect to the counter substrate 30, and is the direction from the lower left to the upper right. The tilt direction of the pretilt of the liquid crystal molecules LC in the display region E is appropriately set based on the optical design conditions of the liquid crystal device 100.

Next, electrical driving of the liquid crystal device 100 will be described with reference to FIG.
A device including the element substrate 20 and the counter substrate 30 arranged to face each other and the liquid crystal layer 40 sandwiched between the pair of substrates is referred to as a liquid crystal panel 110. The liquid crystal device 100 is used with polarizing elements 81 and 82 disposed on the light incident side and the light exit side of the liquid crystal panel 110, respectively. Further, the polarizing elements 81 and 82 are such that the transmission axis or absorption axis of one of the polarizing elements 81 and 82 is parallel to the X direction or the Y direction, and the transmission axes or absorption axes thereof are orthogonal to each other. In this manner, the liquid crystal panel 110 is disposed.

In the present embodiment, a substantially vertical alignment process is performed in the display region E so that the azimuth angle θa of the pretilt of the liquid crystal molecules LC intersects the transmission axes or absorption axes of the polarizing elements 81 and 82 at 45 degrees. Therefore, as shown in FIG. 4A, when the liquid crystal layer 40 is driven by applying a drive voltage between the pixel electrode 28 and the common electrode 34, the liquid crystal molecules LC are tilted in the tilt direction of the pretilt, resulting in high transmission. It is an optical arrangement that provides a good rate.
When driving (ON / OFF) of the liquid crystal layer 40 is repeated, the liquid crystal molecules LC repeatedly behave in such a manner as to fall in the pretilt tilt direction or return to the initial alignment state. Such a substantially vertical alignment treatment in which the behavior of the liquid crystal molecules LC occurs is referred to as a uniaxial substantially vertical alignment treatment.

  The liquid crystal device 100 may include an optical compensation element such as a retardation plate on the light incident side or the light exit side of the liquid crystal panel 110.

  Next, the angular distribution of incident light incident on the liquid crystal panel 110 will be described with reference to FIG. FIG. 5A is a schematic diagram showing a light condensing state with respect to the liquid crystal panel, FIG. 5B is a schematic plan view showing a light incident direction at a corner of the display area, and FIG. It is a schematic sectional drawing which shows the relationship with the orientation of a liquid crystal molecule.

The liquid crystal device 100 of this embodiment is used as a light modulation element (liquid crystal light valve) of a projection display device (liquid crystal projector) described later. In order to effectively use light emitted from the light source, the projection display device is provided with a condensing unit such as an integrator lens 1102 for condensing the light emitted from the light source in a predetermined range (see FIG. 16). A region A1 indicated by a rectangle in FIG. 5A indicates a range of light incident from a light source to a condensing unit such as an integrator lens 1102, for example. The area of the display area E surrounded by the parting portion 14 in the liquid crystal panel 110 is smaller than the area of the area A1. By condensing the light received in the area A1 toward the display area E, the density of the light flux per unit area is increased to enable bright display. On the other hand, as shown in FIG. 5B, since the area of the display area E is smaller than the area of the area A1, the incident angle of the incident light L incident on the corner of the display area E is the display area E. It becomes larger than the incident angle of the incident light L incident on the central portion of the. That is, the incident light L incident on the display area E has a distribution of incident angles.
As described above, the liquid crystal panel 110 is subjected to a uniaxial substantially vertical alignment process. Therefore, for example, as shown in FIG. 5C, in a state in which a driving voltage is not applied to the liquid crystal layer 40, the liquid crystal molecules LC are given a pretilt between the element substrate 20 and the counter substrate 30 to be substantially vertical. Oriented. Therefore, the incident light L does not necessarily enter the liquid crystal molecules LC from a certain direction. Incident incident from the major axis direction of the liquid crystal molecule LC due to the difference between the refractive index n // (parallel) in the major axis direction of the liquid crystal molecule LC and the refractive index n⊥ (perpendicular) in the minor axis direction perpendicular to the major axis direction. The light L is difficult to propagate through the liquid crystal layer 40. Incident light L incident from the minor axis direction intersecting the major axis direction of the liquid crystal molecules LC easily propagates through the liquid crystal layer 40. In other words, in the display area E, there is a possibility that uneven brightness due to the distribution of the incident angles of the incident light L may occur. Therefore, the inventor has developed a microlens ML1 that reduces such uneven brightness.

<Microlens and microlens array substrate>
Hereinafter, the microlens and the microlens array substrate in the present embodiment will be described with reference to FIGS. 6A is a schematic plan view showing a microlens, FIG. 6B is a schematic plan view showing a microlens array substrate in which the brightness of bright display is emphasized, and FIG. 6C includes the microlens array substrate. It is a schematic sectional drawing which shows a liquid crystal panel.
FIG. 6B shows the microlens positioned at the corner of the microlens arranged for each pixel on the microlens array substrate. Further, alphabets A to F are added after the reference numeral 10 indicating the microlens array substrate, and the microlens array substrates of different embodiments to be described later are distinguished. When collectively referred to, the microlens array substrate 10 is used.

  As shown in FIG. 6A, the microlens ML1 of the present embodiment is arranged for each of the square pixels P in plan view, and is provided at a position surrounding the flat portion 12a that is semicircular in plan view and the flat portion 12a. The first lens unit 12b and the second lens unit 12c are provided, and the third lens unit 12d is in contact with the first lens unit 12b and the second lens unit 12c.

  The semicircular flat portion 12a of the microlens ML1 overlaps the arc portion 12ab that is a boundary with the first lens portion 12b and the diagonal line DL of the pixel P, and a straight portion 12ac that is a boundary with the second lens portion 12c. It is comprised by. The diagonal line DL is a virtual straight line from the lower left corner to the upper right corner in the pixel P. The first lens portion 12b has a curved lens surface extending along the arc portion 12ab of the flat portion 12a, and hereinafter, the lens surface may be referred to as a lens surface 12b. The second lens portion 12c has a curved lens surface extending along the straight portion 12ac of the flat portion 12a. Hereinafter, the lens surface may be referred to as a lens surface 12c. The second lens portion 12c is quadrangular in plan view. The third lens portion 12d has a curved lens surface developed in a fan shape around the contact point between the arc portion 12ab and the straight portion 12ac of the flat portion 12a. Hereinafter, the lens surface is referred to as the lens surface 12d. Sometimes called.

  Of the four corners of the pixel P, one corner that is in contact with the first lens unit 12b and two corners that are located diagonally and are in contact with the first lens unit 12b and the third lens unit 12d Are connected portions 12f with adjacent pixels P. A connecting portion 12e exists at the remaining corner portion in contact with the second lens portion 12c. The plane area of the connection part 12e is larger than the plane area of the connection part 12f.

  The arc portion 12ab of the flat portion 12a is a semicircle drawn with a radius R1 with the center of the pixel P as a reference in plan view. That is, the straight line portion 12ac of the flat portion 12a is a straight line passing through the center of the pixel P in plan view. On the diagonal line DL, the length R2 between the arc portion 12ab and the end portion of the connecting portion 12f is the same as the short side length R3 of the second lens portion 12c that is square in plan view. The long side length R4 of the square second lens portion 12c in plan view is twice the radius R1 of the arc portion 12ab.

Such a microlens ML1 is arranged for each pixel P in the display area E as shown in FIG. Moreover, it arrange | positions so that the major axis direction of the liquid crystal molecule LC and the extending direction of the linear part 12ac of the flat part 12a may become parallel. In other words, the microlens array substrate 10A has a plurality of microlenses ML1 arranged so that the major axis direction of the liquid crystal molecules LC is parallel to the extending direction of the straight portion 12ac of the flat portion 12a. .
As shown in FIG. 6C, the liquid crystal molecules LC at this time are applied with a drive voltage to the liquid crystal layer 40 between the element substrate 20 and the counter substrate 30, and the tilt direction defined by the azimuth angle θa described above. It is in a state inclined to. In FIG. 6B, the above-described polarizing elements 81 and 82 are such that one of the polarizing elements 81 and 82 has a transmission axis or an absorption axis parallel to the X direction or the Y direction, and transmits each other. The liquid crystal panel 110A is disposed so that the axis or the absorption axis is orthogonal. Accordingly, the liquid crystal panel 110A shown in FIG. 6C is in a normally black mode in which the pixels P are darkly displayed (black display) when no driving voltage is applied, and the driving voltage is applied to the liquid crystal layer 40 to display liquid crystal molecules. By tilting the LC from the substantially vertical alignment state, bright display (white display) is obtained.

  That is, the liquid crystal panel 110 provided with the microlens array substrate 10A in the present embodiment has a long axis direction of the inclined liquid crystal molecules LC and a straight line portion of the flat portion 12a of the microlens ML1 in the bright display (white display). The extending direction of 12ac is parallel.

FIG. 7A is a schematic cross-sectional view showing the structure of the microlens array substrate taken along the line BB ′ in FIG. 6A, and FIG. 7B is a perspective view showing the microlens. FIG. 7B is a perspective view showing only the portion of the lens layer where the microlens is formed.
As shown in FIG. 7A, the microlens array substrate 10A includes a substrate body 11 and a microlens ML1 formed by filling a concave lens surface 12 provided on the surface 11a of the substrate body 11 with a lens layer 13. And have. The lens surface 12 is a boundary between the flat portion 12a defined by the radius R1, a curved lens surface 12b defined by the radius R2 in contact with the arc portion 12ab which is a boundary between the flat portion 12a, and the flat portion 12a. It is constituted by a curved lens surface 12c defined by a radius R3 in contact with a certain straight line portion 12ac. The length in the thickness direction (that is, the Z direction) of the substrate body 11 from the surface 11a of the substrate body 11 to the flat portion 12a is D1. The length D1 corresponds to the height or depth of the lens surface 12 in the substrate body 11. The microlens ML1 of the present embodiment has a flat portion 12a, so that, for example, the microlens ML1 has a condensing function as compared with a microlens having a semispherical lens surface whose diameter is a length obtained by adding R2 and R3 to R1. The height of the lens surface 12 can be reduced while maintaining the above. The connecting portions 12e and 12f between the adjacent microlenses ML1 form part of the surface 11a of the substrate body 11.

  As shown in FIG.7 (b), the 1st lens part 12b is arrange | positioned so that it may make a semicircle along the circular arc part 12ab of the flat part 12a. The second lens portion 12c is arranged straight along the straight portion 12ac of the flat portion 12a. Therefore, the second lens portion 12c has a cylindrical shape. The third lens portion 12d is disposed so as to fill a space between the first lens portion 12b and the second lens portion 12c.

Next, the condensing function of the microlens ML1 will be described with reference to FIG. FIG. 8A is a schematic plan view for explaining the condensing function of the microlens, and FIG. 8B is a schematic plan view showing the positional relationship between the microlens and the pixel opening in the pixel.
As shown in FIG. 8A, for example, incident light that has entered the pixel P from the counter substrate 30 side along the Z direction travels straight along the Z direction at the flat portion 12a of the microlens ML1. Incident light that has entered the first lens portion 12b is condensed toward the center of the pixel P as indicated by an arrow. On the other hand, the incident light incident on the second lens portion 12c is refracted in a direction orthogonal to the straight portion 12ac of the flat portion 12a and is not condensed at one point, as indicated by an arrow. Incident light that has entered the third lens portion 12d is condensed on the flat portion 12a side.

  As shown in FIG. 8B, the pixel P on which the microlens ML1 is arranged includes a first light shielding layer 22 that extends in at least one of the X direction and the Y direction provided on the element substrate 20 side. It is partitioned by the second light shielding layer 26. That is, the pixel opening OP is defined by the opening 22 a of the first light shielding layer 22 and the opening 26 a of the second light shielding layer 26. In the corner portion of the pixel P, the connecting portions 12e and 12f and the first light-shielding layer 22 and the second light-shielding layer 26 are arranged so as to overlap each other. The shape of the pixel opening OP in plan view is substantially square. According to the arrangement of the microlens ML1 of the present embodiment, in each of the pixels P, incident light incident on the microlens ML1 is collected in the pixel opening OP.

In the present embodiment, as shown in FIG. 6B, the microlens ML1 having such a condensing function includes the major axis direction of the liquid crystal molecules LC during bright display (white display) and the flat portion 12a. It arrange | positions for every pixel P so that the extension direction of the linear part 12ac may become parallel. As described above, the incident angle of the incident light L increases at the corners of the display region E, and the way of light propagation differs between the major axis direction and the minor axis direction of the liquid crystal molecules LC. A difference in transmittance tends to occur between the lower left corner of the display area E along the tilt direction and the upper right corner. According to the microlens ML1 and the arrangement thereof in the present embodiment, the difference in transmittance between the lower left corner of the display area E and the upper right corner can be reduced. Specifically, in the upper right corner, the ratio of the incident light L having a larger incident angle than other portions increases, but the incident light L incident on the second lens portion 12c is in the major axis direction of the liquid crystal molecule LC. Since the light is refracted in the intersecting direction, the transmittance is hardly lowered. Similarly, in the lower left corner, the transmittance is hardly lowered.
Note that the incident angle of the incident light L is large at the upper left corner and the lower right corner of the display region E along the direction orthogonal to the tilt direction of the liquid crystal molecules LC in bright display (white display). Even so, the incident light L incident on the second lens portion 12c is refracted in a direction intersecting the major axis direction of the tilted liquid crystal molecules LC, so that a difference in transmittance hardly occurs. That is, the difference in transmittance in the tilt direction in which the liquid crystal molecules LC are tilted in bright display (white display), that is, uneven brightness is reduced.

  Next, another arrangement method of the microlens ML1 will be described with reference to FIG. FIG. 9A is a schematic plan view showing a microlens array substrate that emphasizes the contrast of dark display, and FIG. 9B is a schematic cross-sectional view of a liquid crystal panel including the microlens array substrate that emphasizes the contrast of dark display. is there.

  In FIG. 6B described above, the microlens ML <b> 1 is disposed with emphasis on improving the brightness unevenness in the bright display (white display). On the other hand, the arrangement of the microlenses ML1 in the microlens array substrate 10B shown in FIG. 9A is an arrangement that places importance on improving the brightness unevenness in the dark display (black display), that is, the contrast unevenness. ing. Specifically, the liquid crystal panel 110B is subjected to a uniaxial substantially vertical alignment process and is used with the polarizing elements 81 and 82, similarly to the liquid crystal panel 110A described above, and thus the optical design is normally black. It is in mode. When a driving voltage is not applied to the liquid crystal layer 40 or when a voltage lower than the threshold voltage (Vth) of the liquid crystal layer 40 is applied, the liquid crystal molecules LC are arranged as shown in FIG. A dark display (black display) state in which the substrate 20 or the counter substrate 30 has a predetermined pretilt and is substantially vertically oriented.

As shown in FIG. 9A, when the liquid crystal molecules LC are in the dark display (black display) state, the microlens ML1 has the extending direction of the straight portion 12ac of the flat portion 12a and the pretilt direction of the liquid crystal molecules LC. Are arranged for each pixel P so as to be orthogonal to each other.
As described above, in the corner portion of the display area E, the ratio of the incident light L having a larger incident angle than that in the central portion is increased. In particular, light leakage is more likely to occur in the lower left corner than in the upper right corner due to the pretilt of the liquid crystal molecules LC. According to the arrangement of the microlens ML1 shown in FIG. 9A, the incident light L incident on the second lens portion 12c is refracted in the tilt direction of the pretilt of the liquid crystal molecules LC. Accordingly, the incident light L becomes more difficult to transmit through the liquid crystal layer 40 and the transmittance in the dark display (black display) is further reduced. Therefore, the unevenness of contrast caused by the pretilt of the liquid crystal molecules LC, particularly the lower left corner and the upper right The difference in contrast with the corners of the is reduced.

<Manufacturing method of microlens array substrate>
Next, a method for manufacturing the microlens array substrate of this embodiment will be described with reference to FIGS. FIG. 10 is a flowchart showing a method for manufacturing a microlens array substrate, FIGS. 11A to 11D and 12E to 12H are schematic cross-sectional views showing a method for manufacturing a microlens array substrate, and FIG. It is a schematic plan view which shows a mask pattern. 11 and 12 corresponds to a cross-sectional view taken along a diagonal line from the upper left to the lower right in the mask pattern of FIG.

  As shown in FIG. 10, the microlens array substrate manufacturing method of this embodiment includes a mask pattern forming step (step S1), an etching step (step S2), a mask pattern removing step (step S3), and a lens layer. A deposition process (step S4), a lens layer polishing process (step S5), and an optical path length adjustment layer forming process (step S6) are provided. The lens layer polishing step corresponds to a step of flattening the lens layer precursor in the method for manufacturing a microlens array substrate of the present invention.

  In the mask pattern forming step (step S1) of FIG. 10, first, as shown in FIG. 11A, the surface 11a of the substrate main body 11 made of, for example, quartz is made of, for example, polycrystalline silicon or the like. A mask layer 71 is formed. Then, the mask layer 71 is patterned using a photolithography technique to form an opening 72 that penetrates the mask layer 71 as shown in FIG. FIG. 13 shows a mask pattern in which an opening 72 is formed. As shown in FIG. 13, the opening 72 has a semicircular shape corresponding to the flat portion 12a in the microlens ML1, and includes an arc portion 72a and a straight portion 72b. The straight line portion 72 b is located on the diagonal line of the pixel P. Then, the process proceeds to step S2.

  In the etching step (step S2) of FIG. 10, the substrate body 11 is subjected to an isotropic etching process through the opening 72 of the mask layer 71 as shown in FIGS. A lens surface (concave portion) 12 is formed on the main body 11. For example, wet etching using an etchant such as a hydrofluoric acid solution is used as the isotropic etching process. By this isotropic etching process, etching proceeds in the thickness direction of the substrate body 11 through the opening 72, and the substrate body faces outward with the arc portion 72a and the straight portion 72b of the opening 72 shown in FIG. 11 is isotropically etched. Specifically, as shown in FIG. 11D, etching proceeds in the thickness direction of the substrate body 11, and the flat portion 12a is formed. Further, the etching proceeds radially from the circular arc portion 72a of the opening 72 shown in FIG. 13 to form the lens surface 12b shown in FIG. 11 (d). Further, the etching proceeds in a direction orthogonal to the extending direction of the linear portion 72b with the straight portion 72b of the opening 72 shown in FIG. 13 as a boundary, and the lens surface 12c shown in FIG. 11D is formed. Further, etching progresses radially around the intersection of the arc portion 72a and the straight portion 72b in the opening 72 of FIG. 13 to form the lens surface 12d (see FIG. 6A or FIG. 7B). Is done. If the isotropic etching is continued, the connecting portions 12e and 12f are etched more than necessary, and the mask layer 71 cannot be supported. Therefore, the isotropic etching needs to be stopped with the connecting portions 12e and 12f remaining. Then, the process proceeds to step S3.

  In the mask pattern removing step (step S3) in FIG. 10, the mask layer 71 is selectively etched and removed as shown in FIG. As a result, the substrate body 11 is formed with connecting portions 12 e and 12 f between the plurality of lens surfaces 12 and the adjacent lens surfaces 12. Then, the process proceeds to step S4.

  In the lens layer deposition step (step S4) of FIG. 10, the lens layer precursor 13p is formed on the one surface 11a side of the substrate body 11. The lens layer precursor 13p is formed so as to embed the lens surface (concave portion) 12 by using an inorganic lens material that is light transmissive and has a refractive index n higher than that of the substrate body 11. In the present embodiment, a lens layer precursor 13p having a layer thickness of, for example, about 10 μm using, for example, a CVD (Chemical Vapor Deposition) method, using SiON (silicon oxynitride) as a lens material for the substrate body 11 made of quartz. Formed. Concavities and convexities corresponding to the plurality of lens surfaces (concave portions) 12 are formed on the upper surface of the lens layer precursor 13p. Then, the process proceeds to step S5.

In the lens layer polishing step (step S5) of FIG. 10, the lens layer precursor 13p is planarized. In this step, for example, the surface of the lens layer precursor 13p is planarized by polishing using a CMP (Chemical Mechanical Polishing) process or the like. Note that the planarization method is not limited to the CMP process, and an etch back method may be used.
Here, the lens layer precursor 13p is moved to a range indicated by a two-dot chain line in FIG. 12 (f) so that the layer thickness of the lens layer precursor 13p covering the surface 11a other than the lens surface (concave portion) 12 is about 3 μm. Grind. FIG. 12G shows the state of the lens layer 13 after the flattening process. Thereby, the microlens ML1 formed by filling the lens surface (concave portion) 12 with the lens material is formed, and the surface 13a of the lens layer 13 opposite to the microlens ML1 is flattened. The above-mentioned layer thickness of the lens layer 13 is combined with the layer thickness of the optical path length adjusting layer 31 to be formed later, and the optical distance such as the focal length of the first lens portion 12b in the microlens ML1 corresponding to the wavelength of light. It is set as appropriate based on the conditions. Then, the process proceeds to step S6.

In the optical path length adjustment layer forming step (step S6) of FIG. 10, as shown in FIG. 12 (h), the optical path length adjustment layer 31 covering the surface 13a of the lens layer 13 is formed. The optical path length adjustment layer 31 is formed with a thick film of SiO ₂ (silicon oxide) by, for example, the CVD method. The layer thickness of the optical path length adjusting layer 31 at this time is, for example, approximately 2 μm to 20 μm. Thereby, the microlens array substrate 10 is completed.

  The counter substrate 30 is completed by further forming a light shielding film 32, a planarizing layer 33, a common electrode 34, and an alignment film 35 on the microlens array substrate 10 manufactured by the above manufacturing method (see FIG. 3). ).

The effects in the first embodiment are as follows.
(1) The microlens array substrate 10 includes microlenses ML1 arranged for each of a plurality of pixels P. Each microlens ML1 has a semicircular flat portion 12a in plan view that transmits the incident light L as it is. The first lens portion 12b arranged along the arc portion 12ab of the flat portion 12a and condenses the incident light L toward the center of the pixel P, and the incident light L arranged along the straight portion 12ac of the flat portion 12a. And a second lens portion 12c that refracts the pixel P in a specific direction. Therefore, the incident light incident on the display region E compared to a microlens that includes a circular flat portion in plan view and a lens portion that is arranged along the flat portion and collects the incident light L toward the center of the pixel P. By defining the extending direction of the cylindrical second lens portion 12c corresponding to the occurrence state of the brightness unevenness caused by the distribution of the L incident angles, the brightness unevenness can be reduced.
(2) In the method of manufacturing the microlens array substrate 10, the plane of the flat portion 12a of the microlens ML1 is formed in the step of forming a mask pattern for etching the lens surface (concave portion) 12 on the substrate body 11 (step S1). A semicircular opening 72 corresponding to the shape is formed in the mask layer 71. If isotropic etching is performed on the substrate body 11 through the opening 72 in the etching process (step S2), the flat portion 12a, the curved lens surface 12b along the arc portion 12ab of the flat portion 12a, and the flat portion 12a. The lens surface (concave portion) 12 including the curved lens surface 12c along the straight line portion 12ac can be formed. By filling the lens surface (concave portion) 12 with a lens material and flattening it, the incident light L is transmitted along the semicircular flat portion 12a and the circular portion 12ab of the flat portion 12a. A first lens portion 12b that condenses the light L toward the center of the pixel P, and a second lens that is disposed along the straight portion 12ac of the flat portion 12a and refracts the incident light L in a specific direction with respect to the pixel P. The microlens ML1 including the lens portion 12c can be formed.
(3) The straight line portion 72b of the semicircular opening 72 of the mask pattern is located on the diagonal line passing through the center and the center of gravity of the pixel P. Since the substrate body 11 is isotropically etched through the opening 72, the region where the first lens portion 12b is formed in plan view with respect to the pixel P is maximized compared to the case where the straight portion 72b is not diagonal. It is possible to That is, it is possible to manufacture the microlens array substrate 10 in which the light collection efficiency of the incident light L that has entered other than the flat portion 12a is increased.
(4) The liquid crystal device 100 (liquid crystal panel 110) provided with the microlens array substrate 10 on the counter substrate 30 on the light incident side is a uniaxial substantially vertical alignment as a method for aligning the liquid crystal molecules LC in the liquid crystal layer 40. Processing method is adopted. If the microlens ML1 is arranged for each pixel P so that the tilt direction of the liquid crystal molecules LC and the extending direction of the cylindrical second lens portion 12c of the microlens ML1 are parallel, bright display (white display) In this case, it is possible to provide a normally black mode liquid crystal device 100 (liquid crystal panel 110A) in which unevenness of brightness in the tilt direction of the liquid crystal molecules LC is reduced. If the microlens ML1 is arranged for each pixel P so that the tilt direction of the liquid crystal molecules LC and the extending direction of the cylindrical second lens portion 12c of the microlens ML1 are orthogonal to each other, dark display (black display) ), A normally black mode liquid crystal device 100 (liquid crystal panel 110B) in which unevenness of contrast in the tilt direction of the liquid crystal molecules LC is reduced can be provided.

(Second Embodiment)
<Liquid crystal device>
Next, a liquid crystal device according to a second embodiment will be described with reference to FIGS. FIGS. 14A to 14C are schematic views for explaining an electrode arrangement, a liquid crystal molecule alignment treatment method, and a driving method in the liquid crystal device of the second embodiment. FIG. 15A is a schematic plan view showing the relationship between the orientation of liquid crystal molecules and the arrangement of microlenses during dark display in the liquid crystal device of the second embodiment, and FIG. 15B is the liquid crystal device of the second embodiment. It is a schematic plan view which shows the relationship between the orientation of the liquid crystal molecule | numerator at the time of bright display in, and arrangement | positioning of a micro lens.
The liquid crystal device according to the second embodiment is different from the liquid crystal device 100 according to the first embodiment in that an IPS (In Plane Switching) method is adopted as a driving method of the liquid crystal layer. The configuration of the microlens ML1 in the microlens array substrate 10 is basically the same. Therefore, the same components as those of the liquid crystal device 100 of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The liquid crystal device according to the present embodiment is an active drive type liquid crystal device similar to the liquid crystal device 100 described above, and has a positive dielectric between the element substrate 20 and the counter substrate 30 as shown in FIG. It has a liquid crystal panel 115 in which a liquid crystal layer 45 made of anisotropic liquid crystal molecules LC is sandwiched. On the side of the element substrate 20 facing the liquid crystal layer 45, a first electrode 28a and a second electrode 28b are provided for each pixel P at a predetermined interval. No electrode is provided on the side of the counter substrate 30 facing the liquid crystal layer 45. The first electrode 28a and the second electrode 28b are referred to as a pair of electrodes 28a and 28b.

  An alignment film (not shown) using, for example, a polyimide resin is formed on each of the element substrate 20 and the counter substrate 30 facing the liquid crystal layer 45. Each alignment film is subjected to an alignment process such as rubbing. As shown in FIG. 14A, the orientation treatment is performed in the direction from the upper right to the lower left as shown by the broken line on the element substrate 20 side so that the azimuth angle θa with respect to the Y direction is 45 degrees, for example. It is rubbing. On the counter substrate 30 side, it is rubbed in the direction from the lower left to the upper right as shown by the solid line. When the driving voltage is not applied to the liquid crystal layer 45 or a voltage equal to or lower than the threshold voltage is applied to the liquid crystal molecules LC, the liquid crystal molecules LC are aligned on the alignment film surface so that the major axis of the liquid crystal molecules LC is along the rubbed direction. Although it has a slight pretilt, it is oriented almost in parallel.

  In the IPS mode, each of the pair of electrodes 28a and 28b provided in the pixel P has a comb-like shape, and the initial alignment state of the liquid crystal molecules LC as described above, for example, as shown in FIG. The pair of electrodes 28a and 28b are extended in the major axis direction of the liquid crystal molecules LC.

  When a driving voltage is applied to the pair of electrodes 28a and 28b arranged in this way, an electric field is generated in a direction intersecting with the extending direction of the pair of electrodes 28a and 28b. As shown in FIG. 14B, the liquid crystal molecules LC having positive dielectric anisotropy are aligned so that the major axis coincides with the electric field generation direction. Then, as shown in FIG. 14C, the liquid crystal molecules LC are maintained in the initial alignment state on the counter substrate 30 side, and are aligned in the direction of the electric field generated between the pair of electrodes 28a and 28b on the element substrate 20 side. Therefore, in the liquid crystal layer 45, the liquid crystal molecules LC are twisted from the counter substrate 30 side toward the element substrate 20 side.

  In such an IPS liquid crystal panel 115, a pair of polarizing elements 81 and 82 (not shown) are arranged with the liquid crystal panel 115 interposed therebetween so that the optical design is a normally black mode. 15A, in the microlens array substrate 10C on the counter substrate 30 side, the extending direction of the linear portion 12ac of the flat portion 12a with respect to the major axis direction of the liquid crystal molecules LC in the initial alignment state. Microlenses ML1 are arranged so that are orthogonal to each other. According to this, since the microlens ML1 includes the cylindrical second lens portion 12c that refracts the incident light L in a specific direction, the distribution of the incident angles of the incident light L in the major axis direction of the liquid crystal molecules LC. A dark display (black display) in which unevenness in contrast due to the above is reduced is realized.

  Further, as shown in FIG. 15B, when the driving voltage is applied to the pair of electrodes 28a and 28b and the liquid crystal molecules LC are twisted as described above, the incident light L in the major axis direction of the liquid crystal molecules LC is reduced. Bright display (white display) in which unevenness in brightness due to the distribution of incident angles is reduced is realized. In other words, if the IPS method is adopted as a method for controlling the alignment of the liquid crystal molecules LC, it is possible to simultaneously improve unevenness in contrast during dark display (black display) and unevenness in brightness during bright display (white display). It becomes possible.

  In the IPS liquid crystal panel 115, when the optical design is a normally white mode, the extending direction of the linear portion 12ac of the flat portion 12a is parallel to the major axis direction of the liquid crystal molecules LC in the initial alignment state. The microlens ML1 is arranged as described above. As a result, unevenness in brightness during bright display (white display) is improved. Further, when a driving voltage is applied to the pair of electrodes 28a and 28b and the liquid crystal molecules LC are twisted as described above, unevenness in contrast due to the distribution of the incident angles of the incident light L in the major axis direction of the liquid crystal molecules LC is caused. Reduced dark display (black display) is realized.

  According to the second embodiment, if the microlens array substrate 10C is applied to the IPS liquid crystal panel 115, the unevenness of contrast during dark display (black display) and the brightness during bright display (white display). It is possible to provide a liquid crystal device in which Sanomura is improved at the same time.

  In addition, by applying the microlens array substrate 10C of the second embodiment, liquid crystal that can simultaneously improve unevenness in contrast during dark display (black display) and unevenness in brightness during bright display (white display). The device method is not limited to the IPS method. For example, the same effect can be obtained even if an FFS (Fringe Field Switching) method is adopted.

  The arrangement of the pair of electrodes 28a and 28b in the IPS liquid crystal panel 115 is not limited to the direction along the major axis direction of the liquid crystal molecules LC in the initial alignment state as described above. For example, a pair of electrodes 28a and 28b are arranged along the Y direction, and the angle formed by the long axis direction of the liquid crystal molecules LC in the initial alignment state and the pair of electrodes 28a and 28b is θa (45 degrees). When a driving voltage is applied to the pair of electrodes 28a and 28b arranged in this way, the liquid crystal molecules LC rotate in the direction of the electric field generated between the pair of electrodes 28a and 28b. It will be along the X direction. Therefore, in the normally black mode, in order to improve contrast unevenness during dark display (black display), as described above, the flat portion 12a has a flat axis 12a with respect to the major axis direction of the liquid crystal molecules LC in the initial alignment state. The microlens ML1 is arranged so that the extending directions of the straight portions 12ac are orthogonal to each other. On the other hand, in order to improve the brightness at the time of bright display (white display), the extension of the straight portion 12ac of the flat portion 12a with respect to the major axis direction of the liquid crystal molecules LC twisted by applying the drive voltage. The microlens ML1 is arranged so that the current direction is parallel. That is, when corresponding to bright display (white display), the straight line portion 12ac of the flat portion 12a of the microlens ML1 extends in the X direction. In other words, in the IPS system as well as the VA system, there are cases where the arrangement of the microlenses ML1 is different between the case where importance is placed on dark display (black display) and the case where importance is placed on bright display (white display).

(Third embodiment)
<Electronic equipment>
Next, a projection display apparatus will be described as an example of the electronic apparatus according to the third embodiment with reference to FIG. FIG. 16 is a schematic diagram illustrating a configuration of a projection display device as an electronic apparatus.

  As shown in FIG. 16, a projection display apparatus 1000 as an electronic apparatus according to this embodiment includes a polarization illumination apparatus 1100 arranged along the system optical axis L0 and two dichroic mirrors 1104 and 1105 as light separation elements. Three reflection mirrors 1106, 1107, 1108, five relay lenses 1201, 1202, 1203, 1204, 1205, three transmissive liquid crystal light valves 1210, 1220, 1230 as light modulation means, and a light combining element As a cross dichroic prism 1206 and a projection lens 1207.

  The polarized light illumination device 1100 is generally configured by a lamp unit 1101 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 1102, and a polarization conversion element 1103.

  The dichroic mirror 1104 reflects red light (R) and transmits green light (G) and blue light (B) among the polarized light beams emitted from the polarization illumination device 1100. Another dichroic mirror 1105 reflects the green light (G) transmitted through the dichroic mirror 1104 and transmits the blue light (B).

The red light (R) reflected by the dichroic mirror 1104 is reflected by the reflection mirror 1106 and then enters the liquid crystal light valve 1210 via the relay lens 1205.
Green light (G) reflected by the dichroic mirror 1105 enters the liquid crystal light valve 1220 via the relay lens 1204.
The blue light (B) transmitted through the dichroic mirror 1105 enters the liquid crystal light valve 1230 via a light guide system including three relay lenses 1201, 1202, 1203 and two reflection mirrors 1107, 1108.

  The liquid crystal light valves 1210, 1220, and 1230 are disposed to face the incident surfaces of the cross dichroic prism 1206 for each color light. The color light incident on the liquid crystal light valves 1210, 1220, and 1230 is modulated based on video information (video signal) and emitted toward the cross dichroic prism 1206. In this prism, four right-angle prisms are bonded together, 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. 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 1300 by the projection lens 1207, which is a projection optical system, and the image is enlarged and displayed.

  The liquid crystal light valve 1210 is the one to which the liquid crystal device 100 of the first embodiment described above is applied. A pair of polarizing elements arranged in crossed Nicols are arranged with a gap between the colored light incident side and the emitting side of the liquid crystal device 100. The same applies to the other liquid crystal light valves 1220 and 1230.

  According to such a projection display apparatus 1000, since the liquid crystal device 100 is used as the liquid crystal light valves 1210, 1220, and 1230, the alignment control of the liquid crystal molecules LC and the distribution of the incident angles of the incident light L are achieved. The unevenness in brightness caused by this can be improved, and the projection display apparatus 1000 having excellent display quality can be provided.

  The electronic apparatus to which the VA liquid crystal device 100 of the first embodiment and the IPS liquid crystal device of the second embodiment can be applied is not limited to the projection display device 1000. For example, a projection type HUD (head-up display), a direct-view type HMD (head-mounted display), an electronic book, a personal computer, a digital still camera, a liquid crystal television, a viewfinder type or a monitor direct-view type video recorder, a car navigation system It can be suitably used as a display unit of an information terminal device such as an electronic notebook or POS.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification, and a microlens array substrate with such a change In addition, liquid crystal devices and electronic devices to which the liquid crystal devices are applied 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 microlens array substrate 10, the microlens ML1 is not limited to being disposed corresponding to all the pixels P in the display area E. FIG. 17A is a schematic plan view showing the microlens array substrate 10D of Modification 1, and FIG. 17B is a schematic plan view showing the configuration of the microlens ML2. In the liquid crystal device 100 of the first embodiment or the liquid crystal device of the second embodiment, for example, as shown in FIG. 17A, the display area E is divided into three parts in the X direction and the Y direction, respectively. Divide into areas. The microlens ML1 is disposed in the pixel P in the first area including the corner of the display area E. Then, the pixels P in the second region other than the first region in the display region E are arranged so as to surround the circular flat portion 15a and the flat portion 15a as shown in FIG. You may arrange | position micro lens ML2 which has the 1st lens part 15b which has a curved lens surface, and the connection part 15c. The center of the flat portion 15a coincides with the center CC on the diagonal line DL of the pixel P. The first lens unit 15b collects incident light toward the center CC. As described above, the microlens ML1 may be partially arranged in the display region E corresponding to the distribution of the incident angles of the incident light L incident on the display region E and the alignment control state of the liquid crystal molecules LC. , The effect.
In the first modification, the microlens ML1 corresponds to the first microlens of the present invention, and the microlens ML2 corresponds to the second microlens of the present invention. Therefore, as a manufacturing method of the microlens array substrate 10D of Modification Example 1 including the microlens ML1 and the microlens ML2, a semicircular opening which is a first opening corresponding to the microlens ML1 is formed in the mask pattern forming step. A portion 72 and a circular second opening corresponding to the microlens ML2 are formed in the mask layer 71.

(Modification 2) In the microlens array substrate 10, the shape of the flat portion 12a is not limited to a semicircular shape. 18A is a schematic plan view showing the configuration of the microlens ML3 of the second modification, and FIG. 18B is a microlens array substrate 10E of the second modification cut along the line CC ′ of FIG. 18A. FIG. As shown in FIG. 18A, the microlens ML3 of Modification 2 includes a flat portion 16a including an arc portion 16ab and a straight portion 16ac, a first lens portion 16b extending along the arc portion 16ab, The second lens portion 16c extends along the straight portion 16ac, and the third lens portion 16d is in contact with the first lens portion 16b and the second lens portion 16c. A connecting portion 16e and a connecting portion 16f exist between the adjacent microlenses ML3. The straight line portion 16ac of the flat portion 16a is not located on the diagonal line DL of the pixel P, and the short side length R13 of the square second lens portion 16c in plan view is the same as that of the first embodiment. This is shorter than the short side length R3 of the second lens portion 12c. The long side length R14 of the square second lens portion 16c in plan view is smaller than the radius R10 of the arc portion 16ab of the flat portion 16a. Note that the center defined by the radius R10 of the circular arc portion 16ab of the flat portion 16a in plan view coincides with the center of the pixel P (the center and the center of gravity of the pixel opening OP).
As shown in FIG. 18B, the microlens array substrate 10E according to the second modification has a flat portion 16a of the microlens ML3 with respect to the microlens array substrate 10 including the microlens ML1 according to the first embodiment. The length R11 is longer. That is, the length of R12 (R13), which is the radius of curvature of the first lens portion 16b and the second lens portion 16c, is smaller than that of the first embodiment. Therefore, the height D2 of the microlens ML3 is lower than the height D1 of the microlens ML1. Therefore, it is possible to reduce the time of isotropic etching for forming the lens surface 16 in the manufacture of the microlens array substrate 10E without significantly reducing the light collection efficiency of the incident light L in the pixel P. The layer thickness of the lens layer precursor 13p for forming the lens layer 13 can be reduced. That is, the microlens array substrate 10E can be manufactured efficiently in terms of man-hours and materials. Further, the size of the connecting portion 16e is smaller than the connecting portion 12e of the microlens array substrate 10 of the first embodiment, and the light condensing performance by the first lens portion 16b is improved.
In other words, in the present invention, if the center defined by the radius of the arc portion of the flat portion matches the center of gravity of the pixel opening OP, the straight portion of the flat portion is on the diagonal line DL passing through the center of the pixel P. The shape of the flat portion in plan view may be larger or smaller than the semicircular shape. The flat portion is formed by isotropic etching of the substrate body 11 of the counter substrate 30, and the pixel opening OP is the opening 22 a of the first light shielding layer 22 formed in the substrate body 21 of the element substrate 20. Or the opening 26 a of the second light shielding layer 26. Therefore, when the liquid crystal device 100 including the microlens array substrate 10 is actually manufactured, it is affected by positional accuracy in the formation of the flat portion, the first light shielding layer 22, and the second light shielding layer 26. It is difficult to completely match the center defined by the radius of the part and the center of gravity of the pixel opening. Therefore, within the range of positional accuracy considering the manufacturing tolerance of the liquid crystal device 100, the center defined by the radius of the arc portion of the flat portion matches the center of gravity of the pixel opening. To do.

(Modification 3) In the microlens array substrate 10 described above, the first lens portion 12b and the second lens portion 12c of the microlens ML1 are not limited to being configured only by curved lens surfaces. FIG. 19 is a schematic cross-sectional view showing the structure of a microlens array substrate 10F of Modification 3. FIG. 19 is a schematic cross-sectional view corresponding to FIG. 7A in the first embodiment. The microlens array substrate 10F of Modification 3 includes a flat portion 12a that defines the height D1 of the microlens ML4, a first lens portion 12b that extends along the arc portion 12ab of the flat portion 12a, and a flat portion 12a. And a second lens portion 12c extending along the straight portion 12ac. The first lens portion 12b includes a curved lens surface 12b and an inclined surface 12g. Similarly, the second lens portion 12c includes a curved lens surface 12c and an inclined surface 12h.
The length of the flat portion 12a on the diagonal line of the pixel P is R1, the length of the first lens portion 12b is R2, and the length of the second lens portion 12c is R3, which is the first embodiment. Is the same. That is, the slopes 12g and 12h may exist between the surface 11a of the substrate body 11 of the lens unit that collects or refracts incident light. The light collection efficiency of incident light can be improved as compared with the case where the lens unit is configured only by a curved surface.

(Modification 4) In the microlens array substrate 10, as shown in FIG. 8, since the planar shape of the pixel opening OP is substantially square, an arc defined by the radius R1 is formed at the center of the pixel opening OP. The center of the part 12ab was located. However, the planar shape of the pixel opening OP may not necessarily be substantially square (point-symmetric shape) depending on the shape and arrangement of the first light shielding layer 22 and the second light shielding layer 26. In this case, the incident light collected by the first lens portion 12b of the microlens ML1 is flat in order to prevent the light collection efficiency from being reduced by entering the first light shielding layer 22 or the second light shielding layer 26. It is preferable to arrange the microlens ML1 so that the center of the arc portion 12ab of the portion 12a is located at the center of gravity of the asymmetric pixel opening OP.
FIG. 20 is a schematic plan view illustrating an example of a pixel opening according to the fourth modification. For example, as shown in FIG. 20, the pixel opening OP defined by the opening 22a of the first light shielding layer 22 and the opening 26a of the second light shielding layer 26 is not a point-symmetrical substantially square, The opening part below the center CC of P may be narrower than the upper part. The center of gravity of the pixel opening OP at this time is a first straight line 91 that vertically divides the pixel opening OP so that the areas thereof are equal to each other, a right angle with the first straight line 91, and a center CC of the pixel P This is the intersection GC with the second straight line 92 that passes through.

  10, 10A, 10B, 10C, 10D, 10E, 10F ... microlens array substrate, 11 ... substrate body, 12 ... lens surface, 12a ... flat portion, 12ab ... flat portion arc portion, 12ac ... flat portion straight portion, 12b ... 1st lens part, 12c ... 2nd lens part, 13 ... Lens layer, 13a ... Surface of lens layer, 13p ... Lens layer precursor, 14 ... Parting part, 20 ... Element substrate, 28 ... Pixel electrode, DESCRIPTION OF SYMBOLS 30 ... Opposite board | substrate, 31 ... Optical path length adjustment layer, 32 ... Light shielding film, 33 ... Planarization layer, 34 ... Common electrode, 40 ... Liquid crystal layer, 72 ... Opening of mask pattern, 72a ... Arc part of opening, 72b DESCRIPTION OF SYMBOLS ... Linear part of opening part, 100 ... Liquid crystal device, 1000 ... Projection type display apparatus as an electronic device, E ... Display area, L ... Incident light, ML1, ML2, ML3, ML4 ... Micro lens, OP ... Pixel opening part, ... pixels.

Claims (15)

A microlens array substrate having microlenses arranged for each of a plurality of pixels on the substrate,
At least some of the microlenses arranged for each of the plurality of pixels are positioned around a flat portion facing the surface of the substrate on the side where incident light is incident and the flat portion. And a first lens part for condensing the incident light toward the center of the pixel, and a second lens part for refracting the incident light in a specific direction with respect to the pixel. Microlens array substrate.   2. The microlens according to claim 1, wherein each of the microlenses arranged for each of the plurality of pixels includes the flat portion, the first lens portion, and the second lens portion. Array substrate.   A first microlens including the flat portion, the first lens portion, and the second lens portion in a first region including a corner portion of the region in the region where the pixels are arranged. The second microlens including the flat portion and the first lens portion is disposed in a second region other than the first region among the regions. Item 4. The microlens array substrate according to Item 1.   4. The flat portion includes an arc portion that becomes a boundary with the first lens portion and a linear portion that becomes a boundary with the second lens portion. 5. The microlens array substrate according to Item. A method of manufacturing a microlens array substrate having microlenses arranged for each of a plurality of pixels on a substrate,
Forming a mask layer covering one surface of the substrate;
Patterning the mask layer to form a mask pattern having an opening;
Forming the lens surface by isotropically etching the substrate through the opening;
Removing the mask pattern;
Forming a lens layer precursor that covers one surface of the substrate and fills the lens surface;
Flattening the surface of the lens layer precursor to form a lens layer;
Forming an optical path length adjustment layer covering the lens layer,
In the step of forming the mask pattern, the opening formed of an arc portion and a straight portion is formed.   In the step of forming the mask pattern, a first opening composed of the arc portion and the linear portion is formed in a first region including a corner portion of the region among regions where the pixels are arranged, 6. The method for manufacturing a microlens array substrate according to claim 5, wherein a circular second opening is formed in a second region other than the first region in the region. A liquid crystal device comprising a pair of substrates and a liquid crystal layer sandwiched between the pair of substrates, wherein one of the pair of substrates has a microlens arranged for each of a plurality of pixels,
At least some of the microlenses arranged for each of the plurality of pixels include a flat portion facing the surface of the one substrate on the side where incident light is incident, and a periphery of the flat portion. A first lens unit that is positioned and collects the incident light toward the center of the pixel; and a second lens unit that refracts the incident light in a specific direction with respect to the pixel. A characteristic liquid crystal device.   8. The liquid crystal device according to claim 7, wherein each of the microlenses arranged for each of the plurality of pixels includes the flat portion, the first lens portion, and the second lens portion. .   A first micro including the flat portion, the first lens portion, and the second lens portion in a first region including a corner portion of the display region in the display region in which the pixels are arranged. A lens is disposed, and a second microlens including the flat portion and the first lens portion is disposed in a second region other than the first region in the display region. The liquid crystal device according to claim 7. The flat portion includes an arc portion that becomes a boundary with the first lens portion, and a linear portion that becomes a boundary with the second lens portion,
The microlens is arranged so that the long axis direction of the liquid crystal molecules in the liquid crystal layer when the pixel is brightly displayed is parallel to the linear portion, and the alignment of the liquid crystal molecules in the liquid crystal layer is controlled. The liquid crystal device according to claim 7, wherein the liquid crystal device is a liquid crystal device. The flat portion includes an arc portion that becomes a boundary with the first lens portion, and a linear portion that becomes a boundary with the second lens portion,
The microlens is arranged so that the long axis direction of the liquid crystal molecules in the liquid crystal layer when the pixel is in dark display and the straight line portion are orthogonal to each other, and the alignment of the liquid crystal molecules in the liquid crystal layer is controlled. The liquid crystal device according to claim 7, wherein the liquid crystal device is a liquid crystal device. The flat portion includes an arc portion that becomes a boundary with the first lens portion, and a linear portion that becomes a boundary with the second lens portion,
The long axis direction of the liquid crystal molecules in the liquid crystal layer when the pixel is in bright display and the straight line portion are parallel to each other, and the long axis direction of the liquid crystal molecules in the liquid crystal layer when the pixel is in dark display and the straight line 10. The liquid crystal device according to claim 7, wherein the microlens is disposed so as to be orthogonal to a portion, and alignment of liquid crystal molecules in the liquid crystal layer is controlled. .   The pixel has a pixel opening section partitioned by a light shielding film, and a center of gravity of the pixel opening section and a center defined by a radius of the arc section match in plan view. The liquid crystal device according to any one of 10 to 12.   The liquid crystal device according to claim 13, wherein the straight line portion of the flat portion passes through the center of gravity of the pixel opening in a plan view.   An electronic apparatus comprising the liquid crystal device according to claim 7.

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