JP2000187212A - Microlens substrate, liquid crystal display element having the microlens and projection type image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microlens substrate, which prevents fluctuation of birefringence due to temperature rise and has satisfactory optical characteristics, and an optical element utilizing it. SOLUTION: A microlens substrate comprises a first transparent substrate 1, on which recessing shapes are formed and a second transparent substrate 2 stuck together via a sealing resin 3. A transparent liquid 4, having a refractive index higher than that of the first transparent substrate 1, is filled in a gap between the first transparent substrate 1 and the second transparent substrate 2 surrounded by the sealing resin 3. The transparent liquid 4 functions as a microlens with projecting shapes. The sealing resin 3 is elastic resin and is preferably silicone resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a microlens substrate, a liquid crystal display device having an improved aperture ratio by adding a microlens, and a projection type image display device using the liquid crystal display device.

[0002]

2. Description of the Related Art In recent years, the demand for liquid crystal display devices has been increasing not only for direct-view display devices but also for image projection display devices such as projection televisions. In the liquid crystal display element, the smallest display unit called a pixel is regularly arranged, and by applying an independent voltage to each of the pixels,
Images and characters are displayed by changing the optical characteristics of the liquid crystal constituting each pixel.

When the liquid crystal display element is used as a projection type display element, when the magnification is increased with a display element having the same number of pixels, the roughness of the screen becomes conspicuous. In order to obtain it, it is necessary to increase the number of pixels.

However, when the number of pixels of the liquid crystal display element is increased, particularly in the case of an active matrix type liquid crystal display element, the ratio of the area occupied by the pixels other than the pixels in the screen becomes relatively large, and these portions are covered. The area of the black matrix increases. As a result, the area of the pixel contributing to the display decreases, and the aperture ratio of the display element decreases. As a result, when the incident light intensity on the liquid crystal display element is the same, the amount of light transmitted through the pixel is reduced, so that the screen becomes dark and the image quality is reduced.

In order to prevent such a decrease in aperture ratio due to an increase in the number of pixels, for example, Japanese Patent Application Laid-Open No. 60-16562 discloses a method.
No. 1 proposes forming a microlens array on one surface of a liquid crystal display element. The microlens array described in this publication has a microlens corresponding to each pixel, and collects light, which has conventionally been shielded by a black matrix, into the pixel.

When microlens substrates in which such a microlens array is formed are classified according to their shapes, there are a convex type and a flat type.

[0007] The convex microlens substrate is formed by forming a convex lens on a transparent flat plate, and the convex surface is exposed on the surface.

As a method of manufacturing a convex microlens substrate, there are a swelling method (Suzuki et al., “A New Manufacturing Method of Plastic Microlens”, 24th Meeting of the Society for Micro-Optics) and a heat sag method (Zoran D. Popovic et al., A
ppl. Optics, 27p. 1281 (198
8)) and a machining method.

In the swelling method, a photosensitive monomer is polymerized by ultraviolet rays, and the exposed portion is swelled by a difference in osmotic pressure generated between an exposed portion and a non-exposed portion to obtain a convex lens shape. In the heat sagging method, a photosensitive resin film is patterned into a predetermined shape such as a circle, and then heated and melted at a temperature higher than the melting point of the resin to obtain a lens shape by surface tension. In the machining method, a lens shape is obtained by shaving a base material.

On the other hand, a flat microlens substrate has no irregularities on the outer surface and has a convex lens embedded inside the substrate.

As a production method, an ion exchange method (App
l. Opt. Vol. 21, p. 1052 (198
2) or Electron. Lett. Vol.
17, p. 452 (1981)) and a glass etching method.

In the ion exchange method, a lens effect is provided by diffusing metal ions into a glass substrate and increasing the refractive index of the portion from the periphery. The glass etching method is
A mask is formed on a glass substrate, and the substrate surface is etched from the mask opening to form a hemispherical concave portion, into which a solid material having a high refractive index is embedded.

Further, a 2P method in which a master having a convex shape or a concave shape is prepared and the shape of the master is reversely transferred by means of an ultraviolet curable resin or the like can be used. According to this 2P method,
A flat microlens substrate is obtained by embedding a resin material or the like having a high refractive index in a concave shape made from a convex original plate, and a convex microlens substrate is obtained from a concave original plate.

In these microlens substrates, microlenses are periodically arranged at a rate of one per pixel or one per a plurality of pixels corresponding to the pixel structure of the liquid crystal display element. By sticking to the display element, the effective aperture ratio can be improved.

In order to bond the flat microlens substrate to the liquid crystal display element, the surfaces to be bonded to each other are simply flat surfaces, so that they may be simply bonded with an optical adhesive.

On the other hand, when the lens surface of the convex microlens substrate is bonded to the liquid crystal display element, a gap needs to be filled, so that the amount of the adhesive used per unit area is smaller than that of the bonding between flat plates. Increase. In addition, since air bubbles are likely to remain in the gaps between the convex lenses on the surface, the surface of the lens is flattened in the same way as a flat plate type by flattening the lens surface with a resin different from the adhesive and further attaching a cover glass. In some cases, it may be bonded to a liquid crystal display element after it has been brought into a state.

If this technique is extended, the flattened microlens substrate itself can be used as a transparent substrate constituting a liquid crystal display element. JP-A-9-2 by the present applicant
In Japanese Patent No. 58195, a first transparent substrate on which a plurality of convex lenses or concave lenses are formed is seal-printed with a UV curable resin or the like around a lens forming portion, and is bonded to a second transparent substrate. A method of manufacturing a microlens substrate by injecting and curing a resin is disclosed.

In this case, the gap between the two transparent substrates is made of resin,
In other words, the solid is filled and solidified, so that the strength of the substrate can be secured. This is used as one substrate of a liquid crystal display element. That is, the substrate in which the microlens is built is put into the manufacturing process of the liquid crystal display element, and the transparent electrode and the alignment film are formed on the surface, and the black matrix is formed as needed, thereby forming the liquid crystal display element. Another thing to do
It is bonded to two transparent substrates via a liquid crystal layer.

[0019]

However, when the microlens manufactured by the above-mentioned conventional technique is applied to a liquid crystal display device in particular, the following problems occur.

The image display principle employed in many liquid crystal panels is called a TN (twisted nematic) method, and is performed by controlling the rotation of the polarization axis by two polarizing plates and a liquid crystal layer between the polarizing plates. Will be

The TN method includes a normally white mode and a normally black mode. Normally white mode means that two polarizing plates are placed so that their polarization axes are orthogonal to each other. When no voltage is applied to the liquid crystal, white display is performed. When the rotation is removed, the display becomes black. On the other hand, in the normally black mode, the polarization axes of two polarizing plates are parallel to each other, and the relationship between voltage application and black-and-white display is reversed.

The ratio of the brightness of the white screen to the brightness of the black screen is called a contrast ratio or simply a contrast. In the normally white mode, the higher the applied voltage in the black display state, the smaller the optical rotation of the liquid crystal and the polarizing plate. Since the extinction ratio approaches its own extinction ratio, the contrast can be increased. On the other hand, in the normally black mode, there is always a light component in which the polarization axis of the light rotated by the liquid crystal layer does not become orthogonal to the polarization axis of the exit-side polarizer and passes through even during black display (zero applied voltage). The contrast does not exceed a certain level.

As described above, the principle of image display of the liquid crystal display element is that polarization is key, and birefringence is sufficiently small so that unnecessary rotation and disturbance of the polarization axis other than the liquid crystal layer does not occur between the two polarizing plates. Constituent materials must be used. Since the microlens substrate is bonded to the liquid crystal display element and is located between the two polarizing plates, the microlens substrate must also have sufficiently small birefringence.

However, in the shape transfer method (2P method) using the ultraviolet curable resin, curing shrinkage occurs when the ultraviolet curable resin is cured, and as a result, anisotropic stress is generated in the resin layer, and May exhibit refractive properties. When such a phenomenon occurs, the light passing through the liquid crystal layer is not orthogonal to the polarization axis of the output side polarizing plate even when displaying a black screen, as in the description of the normally black mode, and sufficient contrast is obtained. There is a problem that the display quality is deteriorated due to the non-uniformity of contrast or the occurrence of uneven contrast.

In particular, in a projection type image display device, since strong illumination light is applied, the liquid crystal display element and the microlens substrate are heated and the temperature rises.

In the convex microlens substrate, the microlens is surrounded by an adhesive on the image display surface,
Further, it is in a state of being sandwiched between glass substrates. Since there is a difference in the coefficient of thermal expansion between the adhesive, the microlens, and the glass substrate, anisotropic stress is applied as the temperature increases. For this reason, the refractive index anisotropy occurs in the material, adhesive, resin, and glass substrate of the microlens, which is optically isotropic at room temperature, and lowers the image quality such as lowering the contrast. Also, in the case of a flat microlens substrate using an etching method, the relationship between the adhesive, the resin embedded as a lens, and the coefficient of thermal expansion with the glass substrate is the same as that of the above-mentioned convex microlens substrate. Occurs.

The glass substrate to which the ion exchange method is applied is mainly soda glass, and has a difference in the coefficient of thermal expansion from that of the non-alkali glass constituting the liquid crystal display element. A position shift occurs, and light cannot be focused on the pixel opening. As a result, there is a problem that image quality is deteriorated such that a projected image becomes dark or brightness unevenness occurs.

The present invention has been made to solve such problems of the prior art, and has a microlens substrate that suppresses an increase in birefringence even when the temperature rises. It is an object of the present invention to provide a liquid crystal display element and a projection type image display device which can obtain the above.

[0029]

A microlens substrate according to the present invention comprises a first transparent substrate having a plurality of concave portions formed on a surface thereof, and a plurality of concave portions formed on the first transparent substrate. And a second transparent substrate disposed so as to be opposed to the first transparent substrate, the peripheral portions of both substrates being bonded together with a sealing resin, and from the injection port provided in the sealing resin. A transparent liquid having a high refractive index is injected between the two substrates, thereby achieving the above object.

It is more preferable to use an elastic resin as the sealing resin.

Further, the sealing resin is more preferably a silicone resin.

In the liquid crystal display device with microlenses of the present invention, the above object is achieved by using the transparent substrate of the liquid crystal display device as the second transparent substrate in the microlens substrate.

A projection type image display device according to the present invention includes at least the liquid crystal display device with microlenses, a light source for supplying light to the liquid crystal display device, and a projection lens for projecting light emitted from the liquid crystal display device. Therefore, the above object is achieved.

Hereinafter, the operation of the present invention will be described. In the microlens substrate of the present invention, the first transparent substrate on which a plurality of concave portions are formed and the peripheral portion of the second transparent substrate are bonded with a sealing resin, and the concave shape is provided between the two substrates. A transparent liquid having a refractive index higher than that of the sealing resin is injected from an injection port provided in the sealing resin. The concave portion provided on the first transparent substrate functions as a container for the liquid lens, and the transparent liquid refracts light as the main component of the convex lens.

Further, since no adhesive is present on the image display surface and the convex lens is a liquid and can freely move around at the molecular level, the stress of thermal expansion at high temperatures is evenly distributed in all directions by the principle of Pascal. Since no birefringence occurs in the microlens portion, the polarization axis of light passing through the microlens is not rotated. Therefore, even when used for a liquid crystal display element, there is no rise in luminance of a black screen, and a sufficient contrast can be maintained.

Liquids generally have a higher coefficient of thermal expansion than solids. However, if a sealing resin having high elasticity such as silicone resin is used, a change in volume of the liquid can be absorbed.

In the liquid crystal display device with microlenses of the present invention, the substrate of the liquid crystal display device is used as the second transparent substrate of the microlens substrate.

A first transparent substrate provided with a concave portion by an etching method or the like and one glass substrate of a liquid crystal display element manufactured by a conventional manufacturing process are bonded together via a sealing resin, and a gap is formed therebetween. By injecting a liquid having a high refractive index, the liquid portion functions as a convex microlens and condenses light at each pixel opening of the liquid crystal display element, so that a bright display image can be obtained.

Further, the projection type image display device including the liquid crystal display device with the microlens substrate, the light source and the projection lens realizes a high quality display image with a bright display screen and no reduction in contrast.

If the first transparent substrate is made of the same material as the transparent substrate of the liquid crystal display element which plays the role of the second transparent substrate, the warpage of the substrate and the position of the microlenses during thermal expansion at a high temperature can be achieved. Since no displacement occurs, the displayed image is not darkened.

[0041]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a sectional view of a microlens substrate according to an embodiment of the present invention.

In this microlens substrate, a first transparent substrate 1 in which a concave shape is formed and a second transparent substrate 2 are bonded via a sealing resin 3, and the first transparent substrate 1 is surrounded by the sealing resin 3. The gap between one transparent substrate 1 and the second transparent substrate 2 is filled with a transparent liquid 4 having a higher refractive index than that of the first transparent substrate 1, and this transparent liquid 4 functions as a convex microlens. .

FIG. 2 shows the manufacturing process of this microlens substrate.
6 will be described with reference to FIG. 3A to FIG.
FIG. 3D is a cross-sectional view taken along line AA shown in FIG. 2.

First, as shown in FIG. 2, a corrosion-resistant metal layer 5 is provided on the surface of the first transparent substrate 1 and a photoresist (not shown) is applied thereon. A desired opening 6 is formed by a technique. In the present embodiment, circular openings 6 are arranged in a grid at equal intervals.

Next, the substrate is immersed in an etchant containing hydrofluoric acid as a main component to form an opening 6 formed in the metal layer 5.
To etch the surface of the first transparent substrate 1 to a predetermined depth. Thus, as shown in FIG. 3A, a hemispherical concave portion 7 is formed immediately below the opening 6.

After that, when the photoresist and the metal layer 5 are removed, as shown in FIG.
An array of concave portions 7 is formed.

As shown in FIG. 3C, the metal layer 8 is formed again in the region where the concave portion 7 is not formed around the first transparent substrate 1 or the metal layer 5 used for the etching is formed.
When the first transparent substrate 1 is further etched, the radius of curvature of the concave portion 7 increases, and the boundary of the concave portion 7 extends over the entire circumference as shown in FIG. And the gap between the lenses after the microlens substrate is completed can be reduced.

FIG. 4 is a perspective view of the first transparent substrate 1 in which the boundary of the concave portion 7 is widened as shown in FIG. Except for the outermost concave shape, the concave portion 7 formed on the first transparent substrate 1 has a rectangular boundary in plan view in a plan view.

Next, as shown in FIG. 5, a sealing resin 3 composed of a mixture of a thermosetting resin and a spacer having a constant diameter is applied to the peripheral portion of the first transparent substrate 1 by printing or dispensing. I do. At this time, the sealing resin 3 is provided with an inlet 9 for injecting the transparent liquid 4 later. Here, as a material of the sealing resin 3, it is more preferable to use a resin having high elasticity such as a silicone resin in order to absorb the volume expansion of the transparent liquid 4 in addition to the epoxy resin used for manufacturing the liquid crystal display element. . The reason why the spacers are mixed in the sealing resin 3 is that when the second transparent substrate 2 is bonded to the first transparent substrate 2, the distance between the first transparent substrate 1 and the second transparent substrate 2 is made uniform to prevent warpage and undulation. To get rid of it.

Next, the first transparent substrate 1 and the second transparent substrate 2 are bonded together with a sealing resin 3.
After curing the first transparent substrate 1 as shown in FIG.
A transparent liquid 4 having a higher refractive index than that of the first transparent substrate 1 is injected between the first transparent substrate 1 and the second transparent substrate 2 from a filling port 9 provided in the sealing resin 3 by a vacuum injection method.

In this vacuum injection method, first, a bonded substrate 10 in which a first transparent substrate 1 and a second transparent substrate 2 are bonded and a transparent liquid 4 are set in a vacuum chamber 11 and a vacuum pump 12 Exhaust. After the inside of the vacuum chamber 11 is sufficiently evacuated, the inlet 9 formed at the peripheral end of the bonded substrate 10 is immersed in the transparent liquid 4. Then, the vacuum chamber 11
By returning the inside to the atmospheric pressure under a nitrogen atmosphere, the transparent liquid 4 enters the gap between the first transparent substrate 1 and the second transparent substrate 2 of the bonded substrate 10 and is filled. Furthermore, if the injection port 9 is sealed with a resin so that the transparent liquid 4 does not leak out, the microlens substrate is completed. Here, since the transparent liquid 4 is injected between the bonded substrates 10 by the vacuum injection method, no bubbles are generated, and the microlens substrate after the sealing of the injection port 9 is easily cleaned. In order to prevent the substrate from being warped or bent due to the difference in the coefficient of thermal expansion when the temperature rises, the second
As the transparent substrate 2, a glass plate made of the same material as the first transparent substrate 1 was used. Instead of the same material, a material having a similar coefficient of thermal expansion may be selected.

The microlens substrate of the present embodiment does not exhibit birefringence even when the temperature rises, and can maintain good optical characteristics particularly in optical applications for handling polarized light and in liquid crystal display devices.

(Embodiment 2) FIG. 7 is a sectional view of a liquid crystal display device with microlenses 13 of the present invention.

This liquid crystal display element with microlenses 13
The bus wiring 16, the switching element 17, the pixel electrode 18 and the like are formed on a transparent substrate 14 made of non-alkali glass, and the black matrix 19 and the transparent electrode 20 are formed on the opposing transparent substrate 15. The transparent substrate 14 and the transparent substrate 15 are adhered to each other by a sealing material 21.
2 are sealed. Although not shown, an alignment film is formed on a surface of the substrate opposite to the transparent substrate 14 and the transparent substrate 15, and the liquid crystal layer 22 is aligned.

The transparent substrate 14 to the transparent substrate 15
Are the same as those of a known active matrix type liquid crystal display element. However, in the liquid crystal display element with a microlens 13 of the present invention, the transparent substrate 23 further provided with the concave portion is provided with the sealing resin 3 on the transparent substrate 15.
, And the gap is filled with the transparent liquid 4. That is, the transparent substrate 15 is used in the first embodiment.
Plays a role of both a second transparent substrate (transparent substrate 2) constituting a microlens substrate and a transparent substrate constituting a liquid crystal display element.

Thus, the liquid crystal display device with microlenses 13 is constituted as a whole as described above.

A method for manufacturing the liquid crystal display element with microlenses 13 will be described below. First, elements extending from the transparent substrate 14 to the transparent substrate 15 are manufactured by a known liquid crystal display element manufacturing method. Note that, in the present invention, the process of the liquid crystal display element may be advanced to the sealing of the liquid crystal layer 22 before bonding to the transparent substrate 23, and there is no need to make any changes to the production line of the liquid crystal display element.

On the other hand, in the same manner as described in the first embodiment, a concave portion is formed on the transparent substrate 23 so as to form a microlens corresponding to the pixel structure of the liquid crystal display element. Here, as the transparent substrate 23, the same non-alkali glass as the transparent substrate 15 to be bonded was used. The radius of curvature of the concave portion is appropriately selected so that the condensed spot of the microlens at the time of completion is adjusted to the liquid crystal layer 22 of the liquid crystal display element.

Next, the processed transparent substrate 23 and the transparent substrate 15 of the liquid crystal display element are bonded together using the sealing resin 3, and the gap is filled with the high-refractive-index transparent liquid 4 using a vacuum injection method. Then, sealing the injection port is the same as in the first embodiment. Thus, a liquid crystal display element with a microlens can be manufactured.

FIG. 8 is a structural view of an optical system of a three-panel projection type color image display device using three liquid crystal display elements with microlenses 13.

This projection type color image display apparatus includes a white light source 24 such as a metal halide lamp, a light source unit 26 including a parabolic mirror 25 for obtaining substantially parallel light, a UV-IR cut filter 27, and a light source unit 26. Dichroic mirrors 28 for decomposing the light into three primary colors of red, green and blue,
Reflector 29, liquid crystal display element 13 with micro lens, field lens 30 for condensing light emitted from liquid crystal display element 13 with micro lens to projection lens 32, primary colors transmitted through liquid crystal display element 13 with micro lens It comprises a dichroic mirror group 31 for synthesizing light and a projection lens 32 for enlarging and projecting an image on a screen 33.

In this projection type color image display device, it is possible to obtain a bright display screen by condensing the light whose microlens is blocked by the black matrix into the pixel openings, as in the prior art. Thus, a high-quality image could be displayed without causing a decrease in contrast even when the temperature increased.

(Embodiment 3) FIGS. 9 and 10 are views for explaining a process of manufacturing a microlens substrate according to another embodiment of the present invention. The main difference from the first embodiment is that the micro lens is changed from a spherical shape to a semi-cylindrical lenticular lens.

First, as in the first embodiment, a corrosion-resistant metal layer 5 is provided on the surface of the first transparent substrate 1.
Further, a photoresist (not shown) is applied thereon, and the metal layer 5 is patterned by photolithography. In the present embodiment, an elongated slit-shaped opening 34 is provided as shown in FIG. 9 according to the shape of the lenticular lens.

Next, when the first transparent substrate 1 is glass-etched and isotropically eroded through the metal layer 5, the long side direction of the slit-shaped opening 34 becomes linear.
The etching proceeds in an arc shape in the short side direction. B in FIG.
A cross-sectional view taken along line -B is almost the same as that shown in FIG. 3 of the first embodiment.

Further, the photoresist and metal layer 5
Is removed, as shown in FIG. 10, the first transparent substrate 1
Is formed with a concave portion 35 having a semi-cylindrical shape.

Thereafter, the first transparent substrate 1 on which the semi-cylindrical concave portion 35 is formed, and the second transparent substrate 2 or a transparent substrate constituting a liquid crystal display element are bonded via a sealing resin 3. After the sealing resin 3 is cured, a gap between the two substrates is filled with a high-refractive-index transparent liquid 4 through an inlet 9 provided in the sealing resin 3 to form a microlens substrate or a liquid crystal display device with microlenses. Is completed.

FIG. 11 is a configuration diagram of an optical system of a projection type color image display device using the liquid crystal display device with microlenses according to the present embodiment. This projection type color image display device uses only one liquid crystal display element to display a full color image, and is a “three-panel type” projection type color image using three liquid crystal display elements described in the second embodiment. It is called “single-plate type” for the display device.

This projection type color image display apparatus comprises a light source section 26 comprising a white light source 24 such as a metal halide lamp, a spherical mirror 36, a condenser lens 37 for converting light from the white light source 24 and the spherical mirror 36 into substantially parallel light, and a UV-light source. A dichroic mirror for separating the light from the IR cut filter 27 and the light source unit 26 into three primary colors of red (R), green (G), and blue (B) and entering the microlens-equipped liquid crystal display element 39 at different angles. It comprises a group 38, a field lens 30 for condensing light emitted from a liquid crystal display element with microlenses 39 onto a projection lens 32, and a projection lens 32 for enlarging and projecting an image on a screen 33.

The pixel array of the liquid crystal display element with microlenses 39 is a so-called stripe array in which pixels of the same color are arranged in the vertical direction of the screen. The microlens array used for this is a red, green, and blue microlens array. Lenticular lenses are arranged at a ratio of one for each of the three color pixel columns.

FIG. 12 is a cross-sectional view for explaining the path of light in the liquid crystal display device with microlenses 39. The red (R), green (G), and blue (B) luminous fluxes split by the dichroic mirror group 38 and incident on the microlens-equipped liquid crystal display element 39 at different angles are respectively subjected to pixel aperture by the microlenses. At the same time as the light is condensed on the unit 40, the light is distributed to pixels that modulate the corresponding colors for red (R), green (G), and blue (B).

Here, unlike the microlenses described in the first and second embodiments, the lenticular lens focuses light only in one direction, so that it is blocked by the black matrix 19 in the direction perpendicular to the plane of FIG. Some light is lost. However, since the absorption type color filter is not used in spite of being a single-plate type, light utilization efficiency is high and a bright projected image can be obtained.

Also in the present embodiment, in addition to the effect of realizing a conventional bright projected image, a high-quality projected image without a decrease in contrast is obtained even when the temperature of the liquid crystal display element is increased.

This embodiment shows that the present invention can produce a lenticular lens-shaped microlens in addition to a spherical shape, and this can be used in combination with a liquid crystal display element. The microlens array applicable to the single-panel projection type color image display device is not limited to the lenticular lens.

Also, as in the first embodiment, a single-lens projection type is achieved by arranging microlenses of a type for condensing light at one point in three ratios of red, green and blue pixels. It is also possible to configure a color image display device.

Further, one microlens is provided for each pixel, and color display is performed using a color filter, or the color of the illumination light is changed to red, green, and blue for each minute time unit, and the illumination light is changed. By sequentially switching and displaying an image of a color corresponding to the color on the liquid crystal display element, it is also possible to constitute a projection type color image display device of a single-plate type.

[0078]

As is clear from the above description, according to the microlens substrate of the present invention, the transparent liquid functions as a convex lens, and even when the temperature rises, the pressure due to the expansion of the materials of each part is evenly dispersed, Does not generate refractive index anisotropy. Therefore, when the present invention is applied to a liquid crystal display element using polarized light, the effective aperture ratio can be improved without lowering the contrast even when the temperature rises.

Further, according to the image projection display device of the present invention, it is possible to provide a projection image display device having a high effective aperture ratio, a bright display screen, and a high quality display image.

Further, the microlens and the liquid crystal display element can be integrated by using the transparent substrate of the liquid crystal display element as a second transparent substrate holding a transparent liquid.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a microlens substrate according to a first embodiment.

FIG. 2 is a perspective view illustrating a manufacturing process of the microlens substrate according to the first embodiment.

FIG. 3 is a cross-sectional view illustrating a manufacturing process of the microlens substrate according to the first embodiment.

FIG. 4 is a perspective view illustrating a manufacturing process of the microlens substrate according to the first embodiment.

FIG. 5 is a plan view illustrating a manufacturing process of the microlens substrate according to the first embodiment.

FIG. 6 is a diagram illustrating a liquid injection step of the microlens substrate according to the first embodiment.

FIG. 7 is a cross-sectional view illustrating a configuration of a liquid crystal display device with a micro lens according to the second embodiment.

FIG. 8 is a configuration diagram of an optical system of a projection type color image display device using a liquid crystal display device with a micro lens according to the second embodiment.

FIG. 9 is a perspective view illustrating a manufacturing process of the microlens substrate according to the third embodiment.

FIG. 10 is a perspective view illustrating a manufacturing process of the microlens substrate according to the third embodiment.

FIG. 11 is a configuration diagram of an optical system of a projection type color image display device using a liquid crystal display device with a microlens according to the third embodiment.

FIG. 12 is a cross-sectional view illustrating a light path in a liquid crystal display device with a micro lens used in the projection color image display device according to the third embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 first transparent substrate 2 second transparent substrate 3 sealing resin 4 transparent liquid 5 metal layer 6 opening 7 concave portion 8 metal layer 9 inlet 10 bonded substrate 11 vacuum tank 12 vacuum pump 13 liquid crystal display with micro lens Element 14 Transparent substrate 15 Transparent substrate 16 Bus wiring 17 Switching element 18 Pixel electrode 19 Black matrix 20 Transparent electrode 21 Sealing material 22 Liquid crystal layer 23 Transparent substrate 24 White light source 25 Parabolic mirror 26 Light source unit 27 UV-IR cut filter 28 Dichroic Mirror group 29 Reflecting mirror 30 Field lens 31 Dichroic mirror group 32 Projection lens 33 Screen 34 Slit-shaped opening 35 Concave part 36 Spherical mirror 37 Condenser lens 38 Dichroic mirror group 39 Liquid crystal display device with micro lens 40 pixel Aperture

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H091 FA14Z FA26X FA26Z FA29Z FA41Z FB02 FB06 FC01 FC17 FC18 FC26 FD15 GA01 HA07 LA04 LA13 LA16 LA17 MA07

Claims (5)

[Claims] A first surface having a plurality of concave portions formed on a surface thereof;
And a second transparent substrate disposed so as to face the surface of the first transparent substrate on which the plurality of concave portions are formed, by bonding the peripheral portions of both substrates together with a sealing resin. A microlens substrate comprising a transparent liquid having a higher refractive index than the first transparent substrate injected between the two substrates from an injection port provided in the sealing resin. 2. The microlens substrate according to claim 1, wherein the sealing resin is an elastic resin. 3. The microlens substrate according to claim 2, wherein the elastic resin is a silicone resin. 4. A liquid crystal display device with microlenses, wherein a transparent substrate constituting a liquid crystal display device is used as the second transparent substrate in the microlens substrate according to claim 1. 5. A liquid crystal display device with a micro lens according to claim 4, a light source for supplying light to the liquid crystal display device, and a projection lens for projecting light emitted from the liquid crystal display device. Projection type image display device.