JPH0882702A - Production of microlens substrate and producing device - Google Patents

Abstract

PURPOSE: To form a black matrix at an accurate position to a microlens array, namely to form a black matrix with its aperture accurately positioned at the focal points of the microlens, and to improve the effective numerical aperture. CONSTITUTION: A black matrix 10 is formed on a microlens substrate 8 equipped with a microlens array 2. Almost parallel beams are made to irradiate the microlens 13 positioned at a specified position on the microlens substrate 8 so that the spots P of condensed light of almost parallel beams produced by the microlens 13 and the apertures 20a of the black matrix 20 formed on a specified position of an exposure mask 19 are aligned.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a microlens substrate used for a high-definition optical element or optical component.

[0002]

2. Description of the Related Art In this specification, a microlens means a minute lens having a size of about several mm or less, and further, such a minute lens is plural, one-dimensionally or two-dimensionally. It includes an arrayed microlens array and a lenticular lens.

In recent years, for example, a liquid crystal panel which is a liquid crystal display element has been in high demand not only as a direct-view type but also as a projection type display element such as a projection television. When a liquid crystal panel is used as a projection type, if the enlargement ratio is increased by the conventional number of picture elements, the roughness of the screen becomes noticeable. Therefore, in order to obtain a fine image even at a high magnification,
It is necessary to increase the number of picture elements.

However, when the number of picture elements of the liquid crystal panel is increased, especially in the active matrix type liquid crystal panel,
The area occupied by the parts other than the picture elements becomes relatively large, and the area of the black matrix covering these parts increases. When the area of the black matrix is increased, the area of the picture element contributing to the display is decreased, and the aperture ratio of the display element is decreased. When the aperture ratio is reduced, the screen becomes dark and the image quality is degraded.

It has been proposed to form a plurality of microlenses on one surface of a liquid crystal panel in order to prevent the reduction of the aperture ratio due to such an increase in the number of picture elements (Japanese Patent Laid-Open No. SHO 61-96).
60-165621-165624, JP-A-60-262131). As described above, by providing the microlens corresponding to each picture element, it becomes possible to condense the light, which is conventionally shielded by the black matrix, into the picture element.

In addition to the above-mentioned applications, the above-mentioned microlens is used as a light-collecting means for an optical pickup such as a laser disk, a compact disk, a magneto-optical disk, etc .; Means; CC
In order to enhance the sensitivity of a solid-state image pickup device such as D or a one-dimensional image sensor used in a facsimile, a condensing means or an imaging means for condensing incident light on a photoelectric conversion region (Japanese Patent Laid-Open No. 54-17620). Japanese Patent Laid-Open No. 57-9180); Image forming means for forming an image to be printed on a photoconductor in a liquid crystal printer or LED printer (See Japanese Patent Laid-Open No. 63-44624); Optical information processing filter It is used as such. As described above, the microlens is used in the optical device in combination with various optical elements or optical components (hereinafter, simply referred to as an optical element).

Further, as a method for manufacturing a microlens, an ion exchange method (Appl. Optics, 21 (6) p.1052 (198
4), Electron Lett., 17 p.452 (1981)), swelling method (Suzuki et al., "New fabrication method for plastic microlenses", 24th Micro Optical Workshop), thermal sag method (Zoran D. Popovic
et al., Appl. Optics, 27 p.1281 (1988)), machining methods, etc.

If the ion exchange method is used, a flat plate type microlens array having a refractive index distribution type microlens can be obtained, and if any other method is used, hemispherical or rotational parabolic (aspherical) refraction is possible. A microlens array having a surface is obtained. In particular, in the case of a microlens array having a hemispherical or paraboloid of refraction surface, this is used as a master (master), and by molding using this master, it is possible to mass-produce the microlens array ( 2P
Method, see JP-A-5-134103).

By bonding these microlens arrays to one surface of the liquid crystal panel, the effective aperture ratio of the liquid crystal panel is improved and a bright display screen can be obtained. The above-mentioned effective aperture ratio means the transmittance of the liquid crystal panel excluding the color filter, the polarizing plate and the like.

However, in a liquid crystal panel for a projection television which performs a high-definition display with a pixel pitch of about several tens of μm, the area of the opening of the display element is further reduced. Therefore, there is a limit to the improvement of the effective aperture ratio by the microlens. This is because the effective aperture ratio is determined by the size relationship between the size of the focused spot of the microlens and the area of the pixel aperture.

The diameter D (μm) of the focused spot is D = 2 · f · tan θ, where θ is the divergence (semi-vertical angle) of the incident light and f (μm) is the focal length of the microlens. ... (1) Therefore, when the area of the focused spot becomes larger than the area of the pixel opening, the light that does not enter the pixel opening does not contribute to the display. Therefore, the effect of improving the effective aperture ratio is reduced.

In the above formula (1), in order to enhance the light collecting effect, it is conceivable to reduce the divergence θ of the incident light and to shorten the focal length f of the microlens. Among these, the divergence degree θ of the incident light becomes smaller as the light emitting area of the light source used is smaller and the distance from the light source to the liquid crystal panel is larger. However, at the current technical level of the light source, it is difficult to set the divergence θ to several degrees or less in order to secure the long life of the light source and the brightness required for display. Therefore, in order to enhance the light-collecting effect, it is necessary to shorten the focal length f of the microlens and bring the focal point of the microlens closer to the pixel aperture of the liquid crystal panel.

Conventionally, as a technique for shortening the focal length of a microlens, a cover glass or film having a thickness corresponding to the focal length is adhered to the surface of the microlens, and the microlens is attached to one substrate (counter substrate) of the liquid crystal panel. A method (Japanese Patent Application Laid-Open No. 3-248125) of making the inside is known. In addition, a lens-shaped portion is formed of a photosensitive resin on the microlens substrate by using the 2P method, and then the microlens substrate is formed with an adhesive having a refractive index different from that of the photosensitive resin. There is known a method (Japanese Patent Laid-Open No. 3-233417) in which cover glasses having the same coefficient of thermal expansion are adhered to each other to improve mass productivity and adhesion. Furthermore, a method of laminating a resin layer having a thickness corresponding to the focal length on the surface of the microlens using a transparent photosensitive resin (Japanese Patent Laid-Open No. 5-27).
No. 3512) is also known. As described above, in any of the short-focus techniques, in order to make the micro-lens short-focus, the micro-lens is formed inside the liquid crystal panel, that is, the counter substrate of the liquid crystal display element.

[0014]

However, when the microlens substrate is manufactured by the above-mentioned conventional method, the following problems occur. That is, when manufacturing a microlens substrate, a cover glass must be attached to form a microlens, and then a transparent electrode, a black matrix, an alignment film, or the like must be laminated on the cover glass surface or the resin layer surface. . Among them, the transparent electrode and the alignment film are uniformly formed in the display area, and therefore, it is not necessary to perform alignment with the microlens.

On the other hand, the black matrix has a lattice-like pattern and is formed by a TFT (Thin Film Transistor).
r) A light-shielding film for protecting the element from light. The black matrix is usually formed by uniformly sputtering a thin film made of aluminum or the like on the surface of the cover glass and then patterning the thin film with an exposure machine using a mask. Then, in order to increase the effective aperture ratio of the black matrix, the opening portion of the black matrix must be accurately positioned at the converging spot of the microlens.

However, in the above conventional method, the microlenses are hidden by the thin film made of aluminum or the like,
I can't see it. Therefore, it becomes impossible to align the mask and the microlens by microscopic observation. That is, in the above-described conventional method, no consideration is given to the position alignment between the mask and the microlens. Therefore, the black matrix may be patterned at a position completely different from the position corresponding to the microlens, and the microlens substrate, that is, the optical element such as a liquid crystal display element manufactured using the microlens substrate may not function at all. There is a problem.

In order to avoid the above problems, if the step of forming the black matrix is omitted, the TFT element is irradiated with stray light that does not contribute to the display. Therefore, TF
The electrical characteristics of the T element are shifted, which causes other problems (detrimental effects) such as a decrease in reliability of an optical element such as a liquid crystal display element and a decrease in display quality.

The present invention has been made in view of the above conventional problems, and an object thereof is a manufacturing method and a manufacturing apparatus of a microlens substrate capable of forming a pattern at an accurate position with respect to a microlens. To provide. Specifically, for example, at the focus of the microlens,
It is an object of the present invention to provide a manufacturing method and a manufacturing apparatus of a microlens substrate capable of forming a pattern such as a black matrix so that the openings are accurately positioned.
The microlens substrate manufactured by the manufacturing method or the manufacturing apparatus according to the present invention can be suitably used for a high-definition optical element, an optical component, or the like, and as a result, an optical element excellent in reliability and display quality. Or optical components, for example,
It is possible to manufacture a high-quality liquid crystal display device or the like that has a bright screen and can obtain a fine image.

[0019]

According to a first aspect of the present invention, there is provided a method of manufacturing a microlens substrate, wherein a pattern is formed on a substrate body having microlenses to solve the above problems. In the method, a microlens located at a predetermined position of the substrate body is irradiated with substantially parallel light, and a condensed spot of the substantially parallel light formed by the microlens and a mark provided at a predetermined position of a pattern forming mask. It is characterized by performing alignment with.

In order to solve the above-mentioned problems, a microlens substrate manufacturing apparatus according to a second aspect of the present invention includes substrate holding means for holding a substrate body, and pattern forming means capable of forming a pattern on the substrate body. In a manufacturing apparatus of a microlens substrate including: an irradiation unit capable of irradiating a microlens of a substrate body held by the substrate holding unit with substantially parallel light; and a substantially parallel light formed by the microlens. It is characterized by comprising a detection means capable of detecting a focused spot.

According to a third aspect of the invention, there is provided an apparatus for manufacturing a microlens substrate according to the second aspect, in order to solve the above problems.
In the microlens substrate manufacturing apparatus described above, the irradiation means is capable of irradiating the microlens with substantially parallel light at an arbitrary irradiation angle.

[0022]

According to the method of claim 1, the substantially parallel light-converging spot formed by the microlens located at the predetermined position of the substrate body and the mark provided at the predetermined position of the pattern forming mask are formed. Make an alignment. Thereby, the pattern can be formed at an accurate position with respect to the microlens. That is, for example, when the pattern is a black matrix or the like, it is possible to form the black matrix or the like so that the opening portion is accurately positioned at the focal point of the microlens, so that the effective aperture ratio can be improved. it can.

According to the second aspect of the present invention, the microlenses of the substrate body held by the substrate holding means are
It is possible to irradiate the substantially parallel light by the irradiation means and detect the condensed spot of the substantially parallel light formed by the microlens by the detection means. Therefore, it is possible to accurately align the position of the focused spot detected by the detection unit and the position of, for example, the pattern forming mask provided in the pattern forming unit.

As a result, by the pattern forming means,
The pattern can be formed at an accurate position on the substrate body, that is, the microlens. That is, for example, when the pattern is a black matrix or the like, it is possible to form the black matrix or the like so that the opening portion is accurately positioned at the focal point of the microlens, so that the effective aperture ratio can be improved. it can.

According to the third aspect of the invention, the irradiation means can irradiate the microlens with substantially parallel light at an arbitrary irradiation angle. Therefore, for example, when manufacturing a microlens substrate used for a twisted nematic (TN) type liquid crystal display element, the irradiation means irradiates the microlens with the above-mentioned substantially parallel light from the optimum viewing angle direction. can do. Therefore,
The liquid crystal display device using the microlens substrate manufactured by the manufacturing apparatus according to the present invention can maximize its viewing angle characteristics. That is, since the liquid crystal display element using the microlens substrate has the maximum image contrast, good contrast can be obtained,
The image quality can be improved.

The microlens substrate manufactured by the above method or the manufacturing apparatus having the above structure can be suitably used for a high-definition optical element or optical component. As a result, it is possible to manufacture an optical element or an optical component having excellent reliability and display quality, such as a high-quality liquid crystal display element having a bright screen and capable of obtaining a fine image.

[0027]

【Example】

[Embodiment 1] One embodiment of the present invention will be described with reference to FIGS.
The explanation is based on the following. In this example, a case where the microlens substrate is used for a liquid crystal display element, that is, a case where a microlens substrate that is suitably used for a liquid crystal display element (optical element, optical component, etc.) is manufactured is taken as an example. Will be explained below. Further, a case of manufacturing an active matrix type liquid crystal display element as the liquid crystal display element will be exemplified.

The method of manufacturing a microlens substrate according to this embodiment is a method of forming a pattern on a substrate body having microlenses, and irradiating the microlenses located at predetermined positions of the substrate body with substantially parallel light. Then, the focused spot of substantially parallel light formed by the microlens is aligned with a mark provided at a predetermined position of the pattern forming mask.

First, the structure of a liquid crystal display device using the microlens substrate manufactured by the above manufacturing method will be described. As shown in FIG. 2, the above liquid crystal display device is
It is an active matrix type liquid crystal display device, and has a transparent substrate 7 made of quartz glass or the like. On the transparent substrate 7, picture element electrodes (not shown), switching elements,
Bus wiring and the like are formed. A liquid crystal layer 6 is sealed between the transparent substrate 7 and a counter substrate 9 facing the transparent substrate 7 with a sealing material 5.

The counter substrate 9 is a microlens substrate (substrate body) 8 and a black matrix (pattern).
10, a transparent electrode 11, and an alignment film 12. The microlens substrate 8 includes a transparent substrate 1 made of quartz glass or the like and a microlens array 2
And an adhesive layer 3 made of an adhesive, and a cover glass 4 made of quartz glass or the like. The black matrix 10, the transparent electrode 11 and the alignment film 12 are arranged in this order on the cover glass 4, that is, the liquid crystal layer 6.
It is laminated on the side surface. The above black matrix 10 has a grid pattern, and TFT (Thin
Film Transistor) A light shielding film for protecting the element from light. The transparent electrode 11 and the alignment film 12 are formed in the display area of the liquid crystal display element with a constant thickness.
The microlens substrate 8 may include a transparent resin layer instead of the cover glass 4.

The above-mentioned microlens array 2 has a plurality of microlenses 2 '... corresponding to each picture element electrode formed on the transparent substrate 7. Further, in this embodiment, the microlenses 2 '... Of the microlens array 2 have a hemispherical (spherical) convex lens shape and are manufactured by the 2P method described above.

As shown in FIG. 1D, the microlens substrate manufacturing apparatus according to the present embodiment has a stage (substrate holding means) having collimators (irradiation means) 22 and 22 (FIG. 3) as a transillumination system. ) 17, and a microscope (detection means)
18 and 18 and exposure mask (pattern forming means) 19
And an ultraviolet irradiation device (pattern forming means) not shown.

As shown in FIG. 3, the stage 17 described above is used.
Is formed in a size capable of mounting (holding) the microlens substrate 8, and the holes 17a
a is opened. The collimators 22 and 22 are
Light with high parallelism, that is, substantially parallel light is emitted. Further, the collimators 22 and 22 can irradiate the microlenses 13 and 13 (to be described later, FIG. 1) of the microlens substrate 8 with substantially parallel light at an arbitrary irradiation angle. Then, the substantially parallel light emitted from the collimators 22 and 22 passes through the holes 17a and 17a and passes through the microlenses 13 and 13 of the microlens substrate 8.
It is designed to be illuminated.

By the way, the above black matrix 10
The shape of the opening is generally rectangular. In addition, if the length of the short side of the opening and the diameter of the focused spot of the microlens 2 ′ are substantially equal to each other, the alignment described later can be easily performed. Then, the parallelism θ of the substantially parallel light
Is represented by L = 2 · f · tan θ (2), where L (μm) is the length of the short side of the opening and f (μm) is the focal length of the microlens 2 ′. Therefore, the collimators 22 and 22 may adjust the parallelism θ of the substantially parallel light so as to satisfy the above expression (2). As a result, the alignment can be performed accurately.

The transillumination system, which is the illuminating means, is only required to have a structure capable of emitting the above-mentioned substantially parallel light. Therefore, the configuration of the transillumination system is the same as the collimator 22.
It is not limited to only. Also, the holes 17a and 17
It suffices that a is opened so that the substantially parallel light can be irradiated to the microlenses 13 and 13. Therefore, the hole 17
The size and shape of the a 17a are not particularly limited. Further, instead of opening the holes 17a ..., The stage 17 may be formed of a transparent material so that the entire stage 17 can transmit the above-described substantially parallel light.

As shown in FIG. 1D, the above-mentioned microscope 1 is used.
8 and 18 are arranged at positions corresponding to the microlenses 13 and 13. Then, the microscope 18 can observe (detect) the position of the condensed spot P of the substantially parallel light formed by the microlens 13. That is,
The substantially parallel light acts as illumination of the microlens substrate 8. The number of microscopes 18 is equal to the number of microlenses 13
The number of microlenses 13 may be the same as that of the microlenses 13 when the microscope 18 is movably arranged.
It may be less than the number of.

The exposure mask (pattern forming mask) 19 is a mask 19a for forming the black matrix 10 on the surface facing the microlens substrate 8.
And a black matrix (mark) 20 used for alignment. The mask 19a has a pattern corresponding to the pattern of the black matrix 10. The black matrix 20 is provided at a predetermined position on the exposure mask 19. The black matrix 20 has openings 20a-2.
0a, and the alignment (so-called,
It is used for mask matching). The exposure mask 19 is
It is movably provided and can be inserted between the microlens substrate 8 and the microscopes 18 and 18.

The ultraviolet irradiation device (not shown) is arranged on the opposite side of the stage 17 with the exposure mask 19 interposed therebetween. The ultraviolet irradiation device irradiates the resist layer 16 (described later) formed on the microlens substrate 8 with ultraviolet rays to expose the resist layer 16. Therefore, the exposure mask 19 and the ultraviolet irradiation device form a pattern forming means.

Next, a method of manufacturing the microlens substrate according to this embodiment will be described below with reference to the steps shown in FIG. The microlens substrate 8 shown in FIG. 1 is upside down in the drawing with the microlens substrate 8 shown in FIG.

First, as shown in FIG.
The microlens substrate 8 is formed by various predetermined methods such as the P method.
Is prepared. At this time, the microlens array 2, that is, a predetermined position of the microlens substrate 8, for example, an end portion,
Microlenses 13 and 13 used for alignment are provided. The microlenses 13 described above are used for alignment when forming the black matrix 10. Therefore, the microlenses 13 ...
It suffices if at least one is provided. The microlens 13
Are provided on the microlens substrate 8, that is, outside the display area of the liquid crystal display element.

In this embodiment, the case where two microlenses 13 are provided will be described.
Therefore, the manufacturing apparatus has a configuration including the two collimators 22 and 22 and the two microscopes 18 and 18, as described above.

Next, as shown in FIG. 7B, metal plate masks 15 and 15 are provided on the cover glass 4 at positions corresponding to the microlenses 13 and 13. Next, a light-shielding film 14 to be the black matrix 10 is formed on the cover glass 4 at a position corresponding to the microlens array 2 by sputtering or the like. The light shielding film 14 is a thin film made of aluminum or the like. Since the positions on the cover glass 4 corresponding to the microlenses 13 are protected by the masks 15 and 15, the light shielding film 14 is not formed at the positions.

Subsequently, as shown in FIG. 6C, after the masks 15 and 15 are peeled off, a photoresist (so-called ultraviolet curable resin) is applied on the light-shielding film 14, that is, the cover glass 4 in a predetermined manner. The resist layer 16 is formed by applying it to a thickness and baking it under predetermined conditions.

Thereafter, as shown in FIG. 3D, the microlens substrate 8 is placed on the stage 17 of the manufacturing apparatus, and the positions of the microlenses 13 and 13 and the stage 1 are set.
Positioning is performed so that the positions of the holes 17a and 17a of 7 match. Next, from the collimators 22 and 22 (FIG. 3) to the hole 1
The microlens substrate 8, that is, the microlenses 13 and 13 are irradiated with substantially parallel light through 7a and 17a, and the focused spots P and P of the microlenses 13 and 13 are observed by the microscopes 18 and 18.

Then, while performing the above observation, the exposure mask 19 is moved so that the above-mentioned focused spots P, P enter the openings 20a, 20a of the black matrix 20 formed on the exposure mask 19, Position. That is, the microlens substrate 8 and the mask 19a of the exposure mask 19 are aligned.

As described above, the black matrix 1
In order to increase the effective aperture ratio of 0, the opening portion of the black matrix 10 must be accurately located at the converging spot of the microlenses 2 '... Therefore, as described above, it is necessary to perform the alignment with high accuracy so that the positional displacement does not occur between the microlenses 2 '... And the black matrix 10.

Then, as shown in FIG. 7E, the resist layer 16 on the microlens substrate 8 is irradiated with ultraviolet rays through an exposure mask 19 from an ultraviolet irradiation device (not shown) to expose the resist layer 16. To do. As a result, the resist layer 16 is cured corresponding to the pattern of the mask 19a of the exposure mask 19. That is, in the resist layer 16, the portion where the ultraviolet rays are blocked by the mask 19a (for convenience, the portion is shaded) is not cured, and only the portion where the ultraviolet rays are irradiated is cured (so-called patterning).

After the exposure process is completed, the resist layer 1
Develop 6. As a result, the resist layer 16 in the shaded area, that is, the uncured photoresist is removed, and only the light-shielding film 14 in that area is exposed. Subsequently, the light shielding film 14 is etched to expose the exposed light shielding film 14.
Is removed. As a result, in the light shielding film 14, only the portion covered with the cured resist layer 16 remains on the cover glass 4. Thereafter, as shown in FIG. 3F, the cured resist layer 16 is peeled off to remove the light-shielding film 14.
Becomes the black matrix 10. That is, the black matrix 10 is formed on the cover glass 4. As a result, the microlens substrate according to this example is manufactured.

Next, the transparent electrode 11 and the alignment film 12 are formed on the microlens substrate 8, that is, on the black matrix 10 by various predetermined methods. The counter substrate 9 is manufactured through the above steps. Since the transparent electrode 11 and the alignment film 12 are formed in the display region of the liquid crystal display device with a constant thickness, it is not necessary to perform alignment.

A liquid crystal display element is manufactured by various methods using the counter substrate 9, the transparent substrate 7, the liquid crystal (liquid crystal layer 6), and the sealing material 5 manufactured as described above. It

As described above, in the method of manufacturing the microlens substrate according to this embodiment, the black matrix 1 is formed on the microlens substrate 8 having the microlens array 2.
0 is a method of forming substantially zero parallel light and irradiating the microlenses 13 located at a predetermined position of the microlens substrate 8 with substantially parallel light to form a focused spot P of substantially parallel light formed by the microlenses 13. This is a method of aligning P with the openings 20a, 20a of the black matrix 20 formed at predetermined positions of the exposure mask 19.

As a result, the black matrix 10 can be formed at an accurate position with respect to the microlens array 2. That is, at the focal point of the microlens 2 '...
Since the black matrix 10 can be formed so that the openings are accurately positioned, the effective aperture ratio can be improved.

As described above, the microlens substrate manufacturing apparatus according to the present embodiment is provided with the stage 17, the exposure mask 19 as the pattern forming means, and the ultraviolet irradiating device. Collimator 2 capable of irradiating substantially parallel light at an arbitrary irradiation angle
2 and 22 and microscopes 18 and 18 capable of observing the positions of the condensed spots P and P of the substantially parallel light formed by the microlenses 13 and 13. Therefore, the microscope 18
It is possible to accurately align the positions of the focused spots P and P observed at 18 with the positions of the openings 20a and 20a of the black matrix 20.

As a result, the black matrix 10 can be formed at an accurate position with respect to the microlens substrate 8, that is, the microlens array 2. That is, since the black matrix 10 can be formed so that the openings thereof are accurately positioned at the focal points of the microlenses 2 '..., The effective aperture ratio can be improved.

The microlens substrate manufactured by the above method or the manufacturing apparatus having the above structure can be suitably used for a high-definition optical element, an optical component or the like. As a result, it is possible to manufacture an optical element or an optical component having excellent reliability and display quality, such as a high-quality liquid crystal display element having a bright screen and capable of obtaining a fine image.

In the above embodiments, the case where the microlenses 13 ... Are provided outside the display area of the liquid crystal display element has been described as an example, but instead of the microlenses 13 ... It is also possible to select at least two or more of the microlenses 2 '... And perform the alignment using these microlenses 2' ...

[Second Embodiment] The following will describe another embodiment of the present invention with reference to FIGS. 4 to 6. For the sake of convenience of description, configurations having the same functions as the configurations shown in the drawings of the first embodiment will be designated by the same reference numerals, and the description thereof will be omitted. In addition, in this embodiment,
A case of manufacturing a microlens substrate which is suitably used for a twisted nematic (TN) type liquid crystal display element will be described as an example.

The liquid crystal display device using the microlens substrate manufactured by the manufacturing method according to this embodiment is a twisted nematic type liquid crystal display device. This liquid crystal display element has a feature that the contrast of the image differs correspondingly when the viewing direction of the display screen is different. Then, in the liquid crystal display element, there is a direction in which the contrast of an image is maximum, that is, an optimum viewing angle direction. Therefore, in general, in a projection type liquid crystal display device, good contrast is obtained by making the illumination light enter from the above-mentioned optimum viewing angle direction.

As shown in FIG. 6, in the above liquid crystal display element, the formation position of the microlens array 2 and the formation position of the black matrix 10 are deviated by a predetermined amount. That is, the black matrix 10 is formed so as to be displaced from the microlenses 2 '... by a predetermined amount.

Here, the normal line of the liquid crystal display element, that is, the microlens substrate 8 is H, and the illumination light incident from the optimum viewing angle direction is S. Further, the incident angle of the illumination light S with respect to the normal line H, that is, the optimum viewing angle is α. Then, the shift amount d (μ of the focused spot of the microlens 2 ′ with respect to the normal line H)
Since the focal length of the microlens 2 ′ is f (μm), m) is represented by d = f · tan α (3). Therefore, as is clear from the above formula (3), the black matrix 10 needs to be formed with a shift of f · tan α (μm) with respect to the microlens array 2. That is, the formation position of the black matrix 10 must be displaced from the formation position of the microlens array 2 by f · tan α (μm). The other structure of the microlens substrate is the same as that of the microlens substrate of the first embodiment. The structure of the manufacturing apparatus of the microlens substrate according to the present embodiment is the same as that of the manufacturing apparatus of the first embodiment.

Next, a method of manufacturing the microlens substrate according to this embodiment will be described below with reference to FIG. In the following description, the description of the same steps as the manufacturing steps of the microlens substrate described in the first embodiment will be simplified.

First, the microlens substrate 8 is manufactured by various predetermined methods such as the 2P method described above, and the cover glass 4 is formed.
Masks 15 and 15 are provided at positions corresponding to the microlenses 13 and 13 above. Next, at the position corresponding to the microlens array 2 on the cover glass 4, the light shielding film 14 to be the black matrix 10 is formed.
Are formed by sputtering or the like. Subsequently, a photoresist is applied to the cover glass 4 in a predetermined thickness and baked under predetermined conditions, whereby the resist layer 16 is formed.
To form.

After that, as shown in FIG. 4, the microlens substrate 8 is placed on the stage 17 of the manufacturing apparatus,
The microlenses 13 and 13 are positioned so that the positions of the holes 17a and 17a of the stage 17 coincide with each other. On the other hand, the stage 17 is arranged so that the incident angle (irradiation angle) of the illumination light S with respect to the normal line H, that is, the optimum viewing angle becomes α.
The collimators 22, 22 installed below are tilted with respect to the normal line H by the optimum viewing angle α. As a result, the illumination light S, which is substantially parallel light, is incident on the microlenses 13 in the optimum viewing angle direction.

Next, the microlens substrate 8, that is, the microlenses 13 and 13 is irradiated with the illumination light S from the collimators 22 and 22 through the holes 17a and 17a, and the focused spot P of the microlenses 13 and 13 is irradiated.・ P is observed with the microscope 18 ・ 18. At this time, the focused spot P
In P, since the illumination light S is incident from the optimum viewing angle direction, as described above, the position deviated by f · tan α (μm) from the center line (normal line H) of the microlenses 13 · 13. Is formed in.

Then, while performing the above observation, the exposure mask 19 is moved so that the above-mentioned focused spots P, P enter the openings 20a, 20a of the black matrix 20 formed on the exposure mask 19, Position. That is, the microlens substrate 8 and the mask 19a of the exposure mask 19 are aligned. As a result, the mask 19a is moved to the center line of the microlenses 2 '...
・ Positioning will be performed accurately at a position shifted by tan α (μm).

Subsequently, the resist layer 16 on the microlens substrate 8 is irradiated with ultraviolet rays from an ultraviolet irradiation device (not shown) through the exposure mask 19 to expose the resist layer 16. Then, after the exposure step, the resist layer 16 is developed, the light shielding film 14 is etched, and the hardened resist layer 16 is peeled off to form the black matrix 10 on the cover glass 4. As a result, the microlens substrate according to this example is manufactured.

As shown in FIG. 5, the black matrix 10 formed as described above has an opening of f · tan α (μ) with respect to the center line of the microlens 2 ′.
It is opened at a position shifted by m). That is, the black matrix 10 is
They are formed with a shift corresponding to the optimum viewing angle α.

Next, the transparent electrode 11 and the alignment film 12 are formed on the microlens substrate 8, that is, the black matrix 10 by various predetermined methods. The counter substrate 9 is manufactured through the above steps. Then, the counter substrate 9 manufactured as described above, the transparent substrate 7,
A liquid crystal display element is manufactured by various predetermined methods using the liquid crystal (liquid crystal layer 6) and the sealing material 5.

As described above, also in the manufacturing method and the manufacturing apparatus for the microlens substrate according to this embodiment, the black matrix is manufactured similarly to the manufacturing method and the manufacturing apparatus for the microlens substrate described in detail in the first embodiment. 10 can be formed at an accurate position with respect to the microlens array 2. That is, at the focal point of the microlens 2 '...
Since the black matrix 10 can be formed so that the openings are accurately positioned, the effective aperture ratio can be improved.

Further, the collimators 22 and 22 can irradiate the microlenses 13 and 13 with substantially parallel light at an arbitrary irradiation angle. Therefore, the collimators 22 and 22 convert the above-mentioned substantially parallel light into the micro lens 13 and
It is possible to irradiate 13 from the optimum viewing angle direction.
That is, in the manufacturing method and the manufacturing apparatus of the microlens substrate according to the present embodiment, the irradiation angle of the substantially parallel light, that is, the optimum viewing angle α is changed according to the viewing angle characteristics of the liquid crystal display element, so that the black matrix 10 is changed. The formation position of can be changed arbitrarily.

Therefore, in the liquid crystal display element using the microlens substrate manufactured by the manufacturing method or the manufacturing apparatus according to the present embodiment, the black matrix 10 with respect to the microlens array 2 is the amount corresponding to the optimum viewing angle α. Since they are formed deviated from each other, the viewing angle characteristics can be utilized to the maximum. That is, since the liquid crystal display device using the microlens substrate has the maximum image contrast, good contrast can be obtained and the image quality can be improved.

[Embodiment 3] The following description will explain still another embodiment of the present invention with reference to FIG.
For the sake of convenience of explanation, the same reference numerals are given to the components having the same functions as the components shown in the drawings of the second embodiment.
The description is omitted.

The microlens substrate manufactured by the manufacturing method according to the present embodiment is suitably used for a twisted nematic type liquid crystal display element, and its constitution is the same as that of the microlens substrate of the second embodiment. Is.

Further, the manufacturing apparatus of the microlens substrate according to this embodiment is different from the manufacturing apparatus of the second embodiment in that
The mask 19a of the exposure mask 19 is f.tan α with respect to the black matrix 20 used for alignment.
It is formed at a position shifted by (μm). That is, when the mask 19a of the manufacturing apparatus according to the present embodiment is aligned, its pattern is displaced by f · tan α (μm) from the center line (normal line H) of the microlenses 2 ′ ... Is formed. The other construction of the microlens substrate manufacturing apparatus is the same as that of the microlens substrate manufacturing apparatus of the second embodiment.

Next, a method for manufacturing the microlens substrate according to this embodiment will be described below with reference to FIG. In the following description, the description of the same steps as the steps of manufacturing the microlens substrate described in the second embodiment will be simplified.

First, the microlens substrate 8 is produced, and the mask 15
15 is provided. Then, the light shielding film 14 is formed at a position corresponding to the microlens array 2. Then, a resist layer 16 is formed on the cover glass 4.

Thereafter, as shown in FIG. 7, the microlens substrate 8 is placed on the stage 17 of the manufacturing apparatus,
The microlenses 13 and 13 are positioned so that the positions of the holes 17a and 17a of the stage 17 coincide with each other. Further, the collimators 22 and 22 installed below the stage 17 are positioned so that the normal line H and the illumination light S are parallel to each other. As a result, the illumination light S that is substantially parallel light is directed to the microlenses 13 in the direction of the normal line H (vertical direction).
Will be incident from.

Next, the microlenses 13 and 13 are irradiated with the illumination light S from the above collimators 22 and 22 through the holes 17a and 17a, and the focused spots P and P of the microlenses 13 and 13 are detected by the microscope 18 and 18. Observe. At this time, the focused spots P, P are the microlenses 13, 13.
Is formed on the center line of.

Then, while performing the above observation, the exposure mask 19 is moved so that the above-mentioned focused spots P, P enter the openings 20a, 20a of the black matrix 20 formed on the exposure mask 19, Position. That is, the microlens substrate 8 and the mask 19a of the exposure mask 19 are aligned.

As described above, the pattern of the mask 19a is f · ta with respect to the center line of the microlenses 2 '...
It is formed so as to be displaced by n α (μm). As a result, the mask 19a becomes the microlens 2 '.
Positioning is accurately performed at a position deviated by f · tan α (μm) from the center line of.

Then, the resist layer 16 on the microlens substrate 8 is irradiated with ultraviolet rays to expose the resist layer 16. Then, after the exposure step, the resist layer 16 is developed, the light shielding film 14 is etched, and the hardened resist layer 16 is peeled off to form the black matrix 10 on the cover glass 4. As a result, the microlens substrate according to this example is manufactured.

The black matrix 10 formed as described above has openings at positions displaced by f · tan α (μm) from the center line of the microlenses 2 ′. That is, the black matrix 10 is formed to be displaced from the microlens array 2 by an amount corresponding to the optimum viewing angle α.

Next, the transparent electrode 11 and the alignment film 12 are formed on the black matrix 10. The counter substrate 9 is manufactured through the above steps. Then, using the counter substrate 9, the transparent substrate 7, the liquid crystal (liquid crystal layer 6), and the sealing material 5 manufactured as described above, a liquid crystal display element is manufactured by various predetermined methods.

As described above, also in the manufacturing method and the manufacturing apparatus for the microlens substrate according to this embodiment, the black matrix is manufactured in the same manner as the manufacturing method and the manufacturing apparatus for the microlens substrate described in detail in the second embodiment. 10 can be formed at an accurate position with respect to the microlens array 2. That is, at the focal point of the microlens 2 '...
Since the black matrix 10 can be formed so that the openings are accurately positioned, the effective aperture ratio can be improved.

Further, in the liquid crystal display element using the microlens substrate manufactured by the manufacturing method or the manufacturing apparatus according to the present embodiment, the black matrix 10 has an amount corresponding to the optimum viewing angle α with respect to the microlens array 2. Since they are formed deviated from each other, the viewing angle characteristics can be utilized to the maximum. That is, since the liquid crystal display device using the microlens substrate has the maximum image contrast, good contrast can be obtained and the image quality can be improved.

[0086]

As described above, the method of manufacturing a microlens substrate according to the first aspect of the present invention is formed by irradiating a microlens located at a predetermined position of the substrate body with substantially parallel light. This is a method of aligning a focused spot of substantially parallel light with a mark provided at a predetermined position of the pattern forming mask.

Further, in the microlens substrate manufacturing apparatus according to the second aspect of the present invention, as described above, the irradiation capable of irradiating the microlenses of the substrate main body held by the substrate holding means with substantially parallel light. And a detection unit capable of detecting a condensed spot of substantially parallel light formed by the microlens.

As a result, there is an effect that the pattern can be formed at an accurate position with respect to the microlens. That is, for example, when the pattern is a black matrix or the like, it is possible to form the black matrix or the like so that the opening portion is accurately positioned at the focal point of the microlens, so that the effective aperture ratio can be improved. It has the effect of being able to.

Further, in the microlens substrate manufacturing apparatus according to claim 3 of the present invention, as described above, the irradiating means is capable of irradiating the microlens with substantially parallel light at an arbitrary irradiation angle. .

Thus, for example, in the case of manufacturing a microlens substrate used for a twisted nematic (TN) type liquid crystal display element, the irradiation means uses the above-mentioned substantially parallel light at an optimum viewing angle with respect to the microlens. It can be irradiated from the direction. Therefore, the liquid crystal display device using the microlens substrate manufactured by the manufacturing apparatus according to the present invention can maximize its viewing angle characteristics. That is, the liquid crystal display device using the microlens substrate has the maximum image contrast, so that good contrast can be obtained and the image quality can be improved.

The microlens substrate manufactured by the above method or the manufacturing apparatus having the above structure can be suitably used for a high-definition optical element or optical component. As a result, it is possible to manufacture an optical element or an optical component having excellent reliability and display quality, such as a high-quality liquid crystal display element having a bright screen and capable of obtaining a fine image.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view illustrating a step in a method for manufacturing a microlens substrate according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a liquid crystal display device manufactured using the microlens substrate.

FIG. 3 is a schematic perspective view of a stage that constitutes the microlens substrate manufacturing apparatus.

FIG. 4 is a schematic sectional view illustrating a method for manufacturing a microlens substrate according to another embodiment of the present invention.

5 is a schematic cross-sectional view of a microlens substrate manufactured by the manufacturing method of FIG.

6 is a schematic cross-sectional view of a liquid crystal display device manufactured using the microlens substrate of FIG.

FIG. 7 is a schematic cross-sectional view illustrating a method of manufacturing a microlens substrate according to still another embodiment of the present invention.

[Description of Reference Signs] 1 transparent substrate 2 microlens array 2'microlens 6 liquid crystal layer 8 microlens substrate (substrate body) 9 counter substrate 10 black matrix (pattern) 13 microlens 17 stage (substrate holding means) 18 microscope (detection) Means) 19 exposure mask (pattern forming means, pattern forming mask) 19a mask 20 black matrix (mark) 22 collimator (irradiation means) P focused spot S illumination light (substantially parallel light) α optimum viewing angle (irradiation angle)

Claims (3)

[Claims] 1. A method of manufacturing a microlens substrate in which a pattern is formed on a substrate body having microlenses, wherein the microlenses located at predetermined positions of the substrate body are irradiated with substantially parallel light to form the microlenses. A method of manufacturing a microlens substrate, comprising: aligning a focused spot of substantially parallel light with a mark provided at a predetermined position of a pattern forming mask. 2. A microlens substrate manufacturing apparatus comprising a substrate holding means for holding a substrate body and a pattern forming means capable of forming a pattern on the substrate body, wherein the substrate body is held by the substrate holding means. Of the microlens, and a detection means capable of detecting a condensed spot of the substantially parallel light formed by the microlens. Substrate manufacturing equipment. 3. An apparatus for manufacturing a microlens substrate according to claim 2, wherein the irradiation means can irradiate the microlens with substantially parallel light at an arbitrary irradiation angle.