JPH07281180A - Liquid crystal display device and its production - Google Patents

Abstract

PURPOSE:To provide a liquid crystal display device in a small size with high precision in which high luminance and high contrast images can be displayed although the opening ratio of pixels is same as that of a conventional device, and to provide its production method. CONSTITUTION:In the area of a quartz substrate 107 covered with an energy beam mask 108, the temp. of the substrate can be raised since the energy beam mask 108 has a function to control the out-flowing of heat caused by irradiation of beams during the substrate is irradiated with beams. Therefore, in the opened part not covered with the mask, various characteristics of the quartz substrate 104 as a substrate can be maintained without modification by irradiation of energy beams. By this method, a microlens array 109 in the pixel part can be easily formed at an accurate position with a good optical shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device having a high brightness display screen.

[0002]

2. Description of the Related Art In recent years, miniaturization and high integration of pixels have been promoted in liquid crystal display devices, and in the case of direct-viewing type liquid crystal display devices, screen size and definition have been increased. On the other hand, a projection type liquid crystal display device (so-called liquid crystal projector) has been developed in order to realize a larger screen.

The projection type liquid crystal display device is capable of displaying a large area screen with a small device body,
An image is formed on a small liquid crystal display panel, light source light is transmitted through this liquid crystal display panel, and enlarged projection is performed on an external screen through an optical system in front of the panel to form a large screen.

In order to make more effective use of the characteristics of this liquid crystal projector, a technique for further miniaturizing the size of the liquid crystal display device used therein has been researched and developed.

For example, even when a liquid crystal display device having a panel size of about 0.7 inch diagonal is used, the number of pixels of the liquid crystal display panel is 300,000 in order to improve the quality of the projected and enlarged image. It is necessary to form the above number of pixels, and in order to realize a liquid crystal display panel having such a large number of pixels, miniaturization and high integration of the liquid crystal display panel are being advanced.

[0006] As a technology capable of meeting such demands,
A method for forming a pixel switching element and a liquid crystal driving circuit as a thin film transistor (TFT) using polycrystalline silicon, and various researches for improving the aperture ratio of each pixel when forming the pixel in a fine and highly integrated manner. Development is being done.

In particular, in the projection type liquid crystal display device as described above, the first requirement for a miniaturized liquid crystal display panel is high brightness (high efficiency of transmitted light).

However, in the prior art, the utilization efficiency of the transmitted light of the liquid crystal display panel can obtain only an aperture ratio of at most about 30 to 40% from the viewpoint of processing accuracy in the manufacturing process of the liquid crystal display device. , The improvement of brightness from the approach of improving the efficiency of use of transmitted light is already near the limit,
The light that is not used is reflected by the light-shielding layer (BLACK MATRIX) and is discarded without being involved in the display.

Here, in the active matrix type liquid crystal display device, the light-shielding layer is generally indispensable because it is necessary to suppress the light leakage current of the TFT and to shield the gap between the pixels to shield the screen. It is a member.

Particularly, in a small and high-definition liquid crystal display panel, this aperture ratio tends to be remarkably lowered with further miniaturization and increase in the number of pixels of each pixel. The decrease in contrast ratio is a problem.

Therefore, as a technique intended to solve the above problems, there is proposed a technique of forming a microlens array by aligning each pixel portion and processing by mechanical processing or etching. ing.

However, with such a technique, although it is possible to increase the amount of light passing through the opening having a small area by the microlens array, it is possible to use such a microlens array having a large number of pixels. It is extremely difficult in practice to accurately form and form each pixel portion, and there is a problem that the alignment accuracy cannot be sufficiently obtained in practical use. The problem with such microfabrication technology is that the liquid crystal display device is
As the resolution becomes higher, the problem becomes more difficult to solve.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and its object is to provide a small-sized and high-definition liquid crystal display device in which the pixel portion aperture ratio is the same as that of the conventional one. An object of the present invention is to provide a liquid crystal display device capable of displaying an image with high brightness and high contrast even as it is, and a manufacturing method thereof.

[0014]

A liquid crystal display device according to the present invention is an array substrate having pixel electrodes arranged in a matrix array on a light-transmissive insulating substrate and switching elements connected to the pixel electrodes. A counter substrate having a counter electrode disposed on a light-transmissive insulating substrate, the counter electrode being arranged to face the pixel electrode substantially in parallel with a gap, and the counter substrate is surrounded by a gap between the array substrate and the counter substrate. Seal and inject
In a liquid crystal display device having a sandwiched liquid crystal layer and a light-shielding film which covers the gap between the pixel electrodes and the switching element and has an opening in a portion corresponding to the pixel electrode, the array substrate and the counter substrate In at least one of the light transmissive insulating substrate or in the light transmissive material layer formed on the light transmissive insulating substrate using a light transmissive material having a different thermal conductivity from the light transmissive insulating substrate, Light is generated by modifying the composition such as the crystallinity or the impurity content of the light-transmissive insulating substrate or the light-transmissive material layer in a portion including the openings in a matrix array at each position corresponding to each of the openings. It is characterized by including a microlens formed by changing the refractive index.

Further, according to the method of manufacturing a liquid crystal display device of the present invention, the light transmissive insulating substrate is provided in at least one of the two light transmissive insulating substrates or the light transmissive insulating substrate having a different thermal conductivity. By selectively irradiating an energy beam in a matrix array shape for each portion corresponding to the pixel portion in the light transmissive material layer formed by using the transmissive material to change the light refractive index of the portion, Forming a microlens having a size including a pixel portion in each of the pixel portions in the light transmissive insulating substrate or in the light transmissive material layer;
On one of the two light-transmissive insulating substrates, pixel electrodes arranged in a matrix array in alignment with the microlenses and switching elements connected to the pixel electrodes are formed to form an array substrate. Forming process,
Forming a counter electrode on the other light-transmissive insulating substrate to form a counter substrate; and a light-shielding film that covers a gap between the switching element and the pixel electrode and has an opening in a portion corresponding to the pixel portion. Is formed on at least one of the array substrate and the counter substrate, and the array substrate and the counter substrate are arranged so as to face each other so that the pixel electrode and the counter electrode face each other with a gap. Sealing the periphery of the array substrate and the counter substrate and injecting liquid crystal into the gap to sandwich the liquid crystal layer.

Alternatively, in the above manufacturing method,
On at least one light-transmissive insulating substrate of the two light-transmissive insulating substrates or on a light-transmissive material layer formed by using a light-transmissive material having a thermal conductivity different from that of the light-transmissive insulating substrate. Forming an energy beam mask material layer made of a material that blocks the energy beam, and patterning openings in a matrix array for each portion corresponding to the pixel portion with respect to the energy beam mask material layer to form an energy beam mask. And a step of selectively irradiating the energy beam in the light-transmissive insulating substrate or the light-transmissive material layer in a portion exposed from the opening of the energy beam mask to change the light refractive index of the portion. And a step of forming a microlens having a size including the pixel portion for each of the pixel portions.

According to the method of manufacturing a liquid crystal display device of the present invention, the pixel electrodes are arranged in a matrix array on one of the two light-transmissive insulating substrates and connected to the pixel electrodes. A step of forming a array element by forming a light-shielding layer having a switching element and covering the gap between the pixel electrodes and the switching element and having an opening for exposing each pixel portion, and the other light-transmissive insulation Forming a counter electrode on the substrate to form a counter substrate;
The array substrate and the counter substrate are arranged so as to face each other with a gap between the pixel electrode and the counter electrode,
By sealing the periphery of the array substrate and the counter substrate,
A step of forming a liquid crystal cell in a sealed empty cell state, and using a light-transmissive material on the outer surface of the light-transmissive insulating substrate of the counter substrate or on the outer surface of the light-transmissive insulating substrate. A step of applying a resist film having resistance to a molten salt containing metal ions on the light transmissive material layer, and irradiating the resist film with light from the array substrate side through an opening of the light shielding layer. And exposing the resist film to form an opening in the exposed region, and a molten salt containing the metal ion in a portion of the light transmissive insulating substrate or the light transmissive material layer exposed from the opening of the resist film. To diffuse the metal ions to change the photorefractive index of the part,
A step of forming a microlens having a size including the pixel portion for each of the pixel portions, and forming an injection hole in a part of the liquid crystal cell in the empty cell state, and injecting a liquid crystal composition from the injection hole. A step of enclosing and sandwiching the liquid crystal layer in the liquid crystal cell.

Alternatively, instead of the resist film having resistance to the molten salt containing the metal ions, a step of applying a resist film having a shielding property against the injection of metal ions, and the step of applying the resist film to the resist film. Exposing the resist film by irradiating light from the side of the array substrate through the opening of the light-shielding layer to form an opening in the exposed region, and the resist of the light-transmissive insulating substrate or the light-transmissive material layer. Projecting the metal ions onto a portion exposed from the opening of the film to change the optical refractive index of the portion, and forming a microlens having a size including the pixel portion in each of the pixel portions;
A step of forming an injection hole in a part of the liquid crystal cell in the empty cell state, injecting a liquid crystal composition through the injection hole, and enclosing and sandwiching it as a liquid crystal layer in the liquid crystal cell. Is characterized by forming a microlens.

Alternatively, in the above manufacturing method, before the step of forming the microlens, a step of forming a cross-sectional shape of an edge portion of a pattern of the energy beam mask, the resist film or the heat storage film into a taper shape, It is characterized by including.

As the above-mentioned energy beam,
For example, an energy beam such as a laser beam, an ion beam, or an electron beam that can apply heat to the sample by irradiating it, or light irradiation of an intense light lamp can be preferably used. .

The above-mentioned resist film is a so-called photosensitive resin film, and it is preferable to use a so-called negative type photosensitive resin film in which a part exposed to light is peeled off and a part not exposed to light remains. it can.

Further, as the heat storage layer, for example, a material such as Si can be preferably used so that the heat is concentrated in the portion when the high frequency energy is applied.

For the above energy beam mask, a metal material such as tungsten silicide can be preferably used. Further, it is preferable to use a metal material such as tungsten silicide because the energy beam mask can also be used as a light shielding film after the microlens array is formed.

As the above-mentioned light transmissive material layer, for example, a film such as a PSG film or a BPSG film having a thermal conductivity and a melting point different from those of a quartz substrate used as a light transmissive insulating substrate can be preferably used. .

The above-mentioned pixel portion microlens array may be formed on the counter substrate side or the TFT array substrate side.

The light-shielding film may be formed on the TFT array substrate side so as to cover the TFT.
Alternatively, in addition to this, it may be further formed on the counter substrate side. At this time, as the light-shielding film provided on the counter substrate side,
As described above, it may also serve as the energy beam mask, or a light-shielding film may be formed separately therefrom.

[0027]

In the present invention, in order to achieve the above object, a microlens (microlens) is provided at a position corresponding to each pixel portion on the counter substrate (or the TFT array side in some cases), and each pixel is provided. Even if the aperture ratio itself for each part is low, the amount of light passing through the aperture is improved by the microlens to improve the amount of transmitted light (light utilization efficiency).

At this time, in order to increase the amount of light transmitted through the pixel portion as much as possible, the misalignment between the microlens and the pixel portion should be minimized, and the distance between the microlens and the light shielding layer should be as large as possible. Is effective. Therefore, in order to form the microlenses on the counter substrate by self-alignment, it is effective to apply a resist or the like on the counter substrate and expose it by self-alignment using the light shielding film of the pixel portion.

Alternatively, in consideration of the process conformity as a liquid crystal display device, an energy beam irradiating device used at the time of forming low-temperature polycrystalline silicon is used to irradiate an energy beam to a portion where a microlens is to be formed. By changing the refractive index of the light-transmissive insulating substrate at that portion or the light-transmissive material layer formed thereon, a microlens can be formed at that portion. By doing this, it is possible to form a microlens array having a suitable shape with good process matching.
At this time, the irradiation position of the energy beam may be sequentially aligned with the standard of the irradiation device for each pixel and irradiation may be performed one shot at a time, but in consideration of heat outflow during beam irradiation, etc., the portions other than the lens formation portion are covered. The energy beam mask is made of a material having good resistance to the energy beam, such as a metal or silicon alloy having good thermal conductivity, and the initial characteristics of the substrate covered by this are preserved and exposed from the mask. It is effective to selectively irradiate the beam only on the existing portion and change the refractive index of that portion. At this time, in forming the pattern of the energy beam mask, if the resist is exposed by self-alignment using a light shielding film and the energy beam mask is patterned using this resist, the microlens can be formed more easily. .

In this way, the microlens array can be formed in an optimized shape, and it is possible to realize a liquid crystal display device in which the amount of transmitted light of the liquid crystal display device is improved by 70% as compared with the conventional one. Becomes

When the energy beam mask as described above is used, the energy beam may be irradiated while scanning the substrate, but in order to further improve the throughput, for example, the energy beams are collectively and appropriately surfaced. An irradiation device that irradiates may be used.

[0032]

Embodiments of the liquid crystal display device and the manufacturing method thereof according to the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a diagram showing a schematic structure of a liquid crystal display device of the first embodiment. In the first embodiment, the light-transmissive insulating substrate on the counter substrate side is irradiated with an energy beam on a portion exposed from the opening of the energy beam mask to form a pixel portion microlens in that portion. , Diagonal 3 inches, pixel pitch 40 μm
A case of manufacturing the polysilicon TFT type liquid crystal display panel of is described.

First, an array substrate 102 on which a general TFT pixel switching element 101 is formed is manufactured. In this embodiment, a quartz substrate 103 is used as a light-transmissive insulating substrate, and amorphous silicon is formed on the quartz substrate 103 by using disilane, followed by low temperature solid phase growth to form a polycrystalline silicon film. After that, the polycrystalline silicon film is separated into islands, and a gate insulating film, a gate electrode, and source / drain regions (all not shown) are formed to fabricate a TFT 101. The light-shielding film 105 is formed on the TFT 101 to obtain the array substrate 102.

On the other hand, on the counter substrate 106 side, a quartz substrate 107 is used as a light-transmissive insulating substrate.
An energy beam mask 108 is formed by depositing tungsten on 07 by a sputtering method and patterning it by a general photolithography method. At this time, as the material that can be used as the energy beam mask, tungsten is selected as described above in this embodiment, but in addition to this, titanium, nickel, chromium, silicon alloy, or the like is used for the energy beam irradiation. A high melting point material having resistance can be suitably used.
In this embodiment, the excimer laser beam XeCl (wavelength 308 nm, pulse interval 12.5) is used as the energy beam.
ns) and the mask was used as a heat storage material.

At this time, if the cross-sectional shape of the edge portion of the pattern of the energy beam mask is formed in a tapered shape as shown in FIG. 1A, a microlens obtained in a later step using this energy beam mask 108. 10
It was found from various experiments by the present inventor that the shape of 9 can be a more preferable lens shape. This is because the tapered shape of the opening of the energy beam mask causes the temperature distribution in the quartz substrate 107 due to the irradiation of the energy beam at the time of forming the pixel microlenses to be close to a Gaussian distribution, and a preferable convex lens shape according to this temperature distribution. It is considered that this is because the pixel portion microlens 109 is formed in the.

After forming the energy beam mask in such a shape, the excimer laser oscillator is used to irradiate the surface of the counter substrate 106 with the excimer laser while scanning the beam with the excimer laser.
The pixel portion microlens 109 is selectively formed only under 8 pixels.

Here, regarding the quartz substrate 107 in the portion not covered with the energy beam mask 108, there is almost no heat outflow caused by the beam irradiation even during the beam irradiation, and the rise in the temperature of the substrate in that portion is reduced. Therefore, various characteristics of the quartz substrate 104 as the substrate can be maintained without being altered by the energy beam irradiation.

After the pixel portion microlens array 109 is formed in this way, the energy beam mask 108 is formed.
And a counter electrode 110 made of a transparent conductive film is formed on the surface of the counter substrate 106 opposite to the surface on which the pixel microlens array 109 is formed by a general method.
Further, alignment films 111a and 111b are formed on the surfaces of the array substrate 102 and the counter substrate 106, respectively. Then, the array substrate 102 and the counter substrate 106 are arranged so as to face each other with a gap, and their periphery is sealed with a sealant adhesive 112 to form a liquid crystal cell in an empty cell state, and the liquid crystal composition is placed in the empty cell. Is injected to seal and sandwich the liquid crystal layer between the substrates. Thus, the liquid crystal display device according to the present invention is completed.

The liquid crystal display device according to the present invention thus manufactured was connected to a liquid crystal drive circuit to display a test image, and its luminance was measured. As a result, a conventional liquid crystal display having an aperture ratio similar to this was displayed. Compared to the device, the brightness of the displayed image is
It was confirmed that it could be improved by 40% or more.

The preferable angle θ of the taper of the sectional shape of the edge portion of the above energy beam mask is
It is desirable to set 5 ° <θ <75 °, more preferably 10 ° <θ <60 °.

Example 2 The microlens array according to the present invention is not only formed in the light transmissive insulating substrate, but also
Alternatively, a light-transmitting material layer on which the microlens array is to be formed may be formed on the substrate separately from the substrate, and the microlens array may be formed in the light-transmitting material layer. In this embodiment, a manufacturing method in such a case will be described.

As shown in FIG. 2, P is formed on the quartz substrate 107.
The SG film 301 is formed. This PSG film 301 is a CV
A film having a thickness of 800 nm was formed by the D method. Furthermore this PS
The energy beam mask 1 is formed on the G film 301 by using tungsten silicide in the same manner as in the first embodiment.
08 is formed.

Then, when the excimer laser is irradiated as an energy beam to the PSG film 301 immediately below the energy beam mask 108, the PSG film 301 in that part is melted, and after the beam irradiation is completed, it is gradually cooled and solidified. Go. At this time, since a tungsten silicide film is deposited as the energy beam mask 108 on the portion irradiated with the energy beam, the tungsten silicide is heated and solidified by cooling from the opening portion where the temperature did not rise. Occurs, and the central part is finally solidified, which causes a difference in temperature distribution over time of the PSG film 301. As a result, the concentration of P (phosphorus) in the opening of the energy beam mask 108, that is, the peripheral portion of the pixel portion decreases, while the concentration increases in the central portion. In this way, the refractive index of the PSG film 301 increases in the central portion of the pixel portion and decreases in the peripheral portion, so that the pixel portion microlens 109 having good optical characteristics is formed.

At this time, instead of the PSG film 301 described above, a light transmissive material film such as a BPSG film containing boron can be used.

After that, the liquid crystal display device according to the present invention is completed by using the counter substrate 106 on which the pixel microlenses 109 are formed as described above, through the same steps as those in the first embodiment. can do.

(Embodiment 3) In the third embodiment, a light-shielding film is formed on the array substrate side, a liquid crystal cell in an empty cell state is formed using the array substrate, and then the outer surface side of the counter substrate is formed. A resist film is deposited on the substrate, the resist film is exposed from the array substrate side by self-alignment using the light-shielding film, and patterned, and a microlens is formed on the light-transmissive insulating substrate on the counter substrate side based on the resist pattern. A technique for forming the will be described. Note that, in FIG. 3, the same parts as those in each of the above-described embodiments are denoted by the same reference numerals.

First, the array substrate 102 having the TFT 101 as a general pixel switching element is manufactured. That is, the TFT 101 is formed on the quartz substrate 103, and the light-shielding film 1 is further formed on the TFT 101 via the interlayer insulating layer 104.
Form 05. Thus, the main part of the array substrate 102 is manufactured. The detailed method of forming the array substrate 102 is as described in the first embodiment.

Although tungsten silicide is used as the light-shielding film 105 in this embodiment, a refractory metal such as titanium or nickel, or its silicide, or a light-shielding material such as chrome is also used. A high metal material or the like can be preferably used. Alternatively, the light shielding film 105 may be formed in a layer between the TFT 101 and the quartz substrate 103, or may be formed on the outer surface side of the quartz substrate 103. Alternatively, in addition to the above metal-based material such as tungsten silicide, an organic material represented by polyimide, for example, may be used.

The array substrate 102 on which the main portion is formed in this manner is replaced with the counter substrate 1 on which the counter electrode 110 is formed.
The substrates are arranged so as to face each other with a gap at 06, and the periphery of both substrates is sealed with the adhesive / sealant 112 to form a so-called empty liquid crystal cell.

Here, the substrate of the counter substrate 106 is N
A glass substrate 401 containing alkali ions such as a ⁺ was used instead of the quartz substrate 107 used in the above-mentioned embodiment.
This is because, as described later, the microlens 109 according to the present invention is formed in the glass substrate 401 by the ion exchange method.

After that, the microlens 109, which is the main part of the technique of the present invention, is formed.

That is, after applying a resist film to the outer surface side of the counter substrate 106, light is irradiated from the array substrate side. At this time, the resist film is exposed by self-alignment using the light shielding film 105. In this way, the resist is left only in the portion corresponding to the region where the light-shielding film is formed, and the resist in other portions (exposed portion) is removed,
A resist pattern 402 having an opening in that portion is formed.

Subsequently, the resist 403 is applied to the outer surface of the quartz substrate 103 on the array substrate side almost all over the surface to shield it.

Then, the liquid crystal cell in such a state is immersed in a molten salt containing metal ions. In this way, the alkali ions in the glass substrate 401 and the metal ions contained in the molten salt are mutually diffused and exchanged, and the material of the glass substrate 401 at that portion is altered to become a portion having a different refractive index. . This portion becomes a portion having a lens effect, and the microlens 109 is obtained.

At this time, the microlens 109 is formed as a convex lens having a suitable optical shape centered on the resist opening, and moreover, self-alignment is performed by using the light shielding film 105 which defines the pixel area already formed on the array substrate. Since it is formed by, it is not necessary to perform high-precision alignment of a conventional photomask, and the microlens 109 can be easily formed with accurate alignment to all pixels. Then, the above-mentioned resist 40
2, 403 are peeled off, and a liquid crystal composition (not shown) is injected into the cell in the empty cell state to be enclosed and sandwiched as a liquid crystal layer to obtain the liquid crystal display device according to the present invention. Needless to say, the opening used for injecting the liquid crystal layer is sealed so that the liquid crystal does not leak.

The display screen of the liquid crystal display device of the third embodiment according to the present invention produced in this manner shows an improvement in brightness of 53% or more as compared with the conventional liquid crystal display panel having the same aperture ratio. It was confirmed that it was done.

Furthermore, the present inventor has confirmed from experimental results and trial calculation results that it is possible to realize higher brightness in combination with further improvement of the technology of the light source and the optical system.

(Embodiment 4) By forming the pattern edge of the resist 402 in the above-mentioned third embodiment into a tapered sectional shape, the microlens 109 having a more preferable shape can be formed. A liquid crystal display device of the fourth embodiment having such a structure is shown in FIG.

Since a taper angle is provided at each of the pattern edge portions of the resist 402, the diffusion of the metal ions described above becomes gradually slower and slower from thin film thickness to thick film thickness according to the taper. Therefore, the resist 40
The glass substrate 4 of the exposed portion where 2 is not applied
For 01, metal ions are diffused in a deep and high concentration,
The closer to the periphery where the resist is thickly deposited, and toward the center of the resist from the taper (that is, toward the periphery of the opening), the lower the metal ion diffusion and the lower concentration. Corresponding to such a concentration distribution, the microlens 109 having a shape that realizes an optically more suitable refractive index can be formed.

As described above, even when the microlenses are formed by using the ion exchange method, the microlenses having a suitable optical shape can be obtained by forming the edges of the resist in the manufacturing method according to the present invention by tapering. Obtainable.

(Fifth Embodiment) In the third to fourth embodiments, a molten salt containing metal ions is used in order to diffuse the metal ions into the glass substrate to form the microlens 109. By using the ion implantation method without using such a wet material,
The microlens 109 according to the present invention can be formed. Therefore, in the fifth embodiment, a method of forming the microlens 109 by the ion implantation method will be described with reference to FIG.

Microlens 109 by ion implantation method
It is desirable to implant ions having the heaviest inertial weight as much as possible in the formation of a shallow region. Therefore, the present inventor performed ion implantation using arsenic (As) under various conditions such as experimental apparatus when various experiments were performed to complete the present invention. That is, in the fifth embodiment, the quartz substrate 107 is used as the light transmissive insulating substrate. And other TFT 101 and array substrate 1
The structure of No. 02 and the material used therefor are almost the same as those in the above-mentioned third and fourth embodiments, and the resist 402 used in the above-mentioned third and fourth embodiments and the like. Using, the arsenic ions were implanted into the portion of the quartz substrate 107 exposed from the opening of the resist 402 by a so-called ion implantation method. However, at this time, needless to say, the resist 402 is not limited to the above materials. A resist that can effectively block ion implantation during ion implantation and that can be patterned by self-alignment as described above can be preferably used.

As described above, ions are selectively implanted into each portion of the quartz substrate 107 corresponding to each pixel portion, and the refractive index of that portion is determined by refraction of the quartz substrate of the portion not ion-implanted. Compared with the rate.

As a result, the original refractive index of the quartz substrate 107 was 1.45, but the refractive index of the ion-implanted region was changed to 1.51, and the microlens 109 was formed in this portion. It was confirmed that it was done. Thus, it was confirmed that the microlens 109 can be formed in each region corresponding to each pixel portion by the manufacturing method as described above.

In the microlenses 109 obtained in this example, a very remarkable result that the improvement of the transmitted light utilization efficiency exceeds 50% as in the above-mentioned examples is obtained in the above experiment. There wasn't. However, it goes without saying that the refractive index of the microlens array 109 formed by ion implantation can be changed more effectively by implanting ions at a higher concentration than in this embodiment. As a result, it is considered that it becomes possible to form a microlens array having a more effective refractive index and realizing a better light utilization efficiency.

In each of the above embodiments, the case where the microlens array is formed in the quartz substrate on the counter substrate side, the glass substrate, or the light transmissive material layer is shown, but the present invention is not limited to this. Is not limited. It goes without saying that the manufacturing method of each of the above-described embodiments can be applied to the array substrate side depending on the traveling direction of the light source light.

[0068]

As described above in detail, according to the present invention, in a small and high definition liquid crystal display device,
It is possible to provide a liquid crystal display device capable of displaying an image with higher brightness and higher contrast and a method for manufacturing the same, even though the aperture ratio of the pixel portion remains the same.

[Brief description of drawings]

FIG. 1 is a diagram showing a liquid crystal display device and a manufacturing method thereof according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a liquid crystal display device and a manufacturing method thereof according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a liquid crystal display device and a method for manufacturing the same according to a third embodiment of the present invention.

FIG. 4 is a diagram showing a liquid crystal display device and a method of manufacturing the same according to a fourth embodiment of the present invention.

FIG. 5 is a diagram showing a liquid crystal display device and a method of manufacturing the same according to a fifth embodiment of the present invention.

[Explanation of symbols]

 101 ... TFT 102 ... Array substrate 103 ... Quartz substrate 104 ... Interlayer insulating film 105 ... Light-shielding film 106 ... Counter substrate 107 ... Quartz substrate 108 ... Energy beam mask 109 ... Microlens 110 ... Counterface Electrodes 111a, b ... Alignment film 112 ... Sealant adhesive 401 ... Glass substrate 402 ... Resist pattern

Claims (6)

[Claims] 1. An array substrate on which pixel electrodes arranged in a matrix array and switching elements connected to the pixel electrodes are formed on a light-transmissive insulating substrate; A counter substrate in which counter electrodes arranged to face each other with a gap are formed on a light-transmissive insulating substrate, and a liquid crystal layer is filled and sandwiched around the gap between the array substrate and the counter substrate. And a light-shielding film that covers the gap between the pixel electrodes and the switching element and has an opening in a portion corresponding to the pixel electrode, wherein light of at least one of the array substrate and the counter substrate is provided. Each of the above in a transparent insulating substrate or in a light transparent material layer formed on the light transparent insulating substrate by using a light transparent material having a thermal conductivity different from that of the light transparent insulating substrate. A microlens formed by changing the crystallinity or the impurity content of a portion including the opening in a matrix array at each position corresponding to the mouth to change the optical refractive index of the portion. Liquid crystal display device. 2. A light-transmitting material formed in a light-transmitting insulating substrate of at least one of the two light-transmitting insulating substrates or using a light-transmitting material having a thermal conductivity different from that of the light-transmitting insulating substrate. The portion corresponding to the pixel portion in the conductive material layer is selectively irradiated with an energy beam in a matrix array to change the photorefractive index of the portion, and the microlens having a size including the pixel portion is formed. Forming in each of the pixel units in the light-transmissive insulating substrate or in the light-transmissive material layer, and aligning the position of the microlens on one of the two light-transmissive insulating substrates. Forming an array substrate by forming pixel electrodes arranged in a matrix array at positions and switching elements connected to the pixel electrodes, and forming a counter electrode on the other light-transmissive insulating substrate and a counter substrate To And a step of forming a light-shielding film that covers a gap between the switching element and the pixel electrode and has an opening in a portion corresponding to the pixel portion on at least one of the array substrate and the counter substrate, The array substrate and the counter substrate are arranged so as to face each other with a gap between the pixel electrode and the counter electrode,
And a step of sealing the periphery of the array substrate and the counter substrate and injecting liquid crystal into the gap to sandwich it as a liquid crystal layer. 3. The method of manufacturing a liquid crystal display device according to claim 2, wherein at least one of the two light-transmissive insulating substrates or the light-transmissive insulating substrate has a thermal conductivity. An energy beam mask material layer made of a material that blocks the energy beam is formed on a light transmissive material layer formed by using a different light transmissive material, and the energy beam mask material layer corresponds to a pixel portion. Forming an energy beam mask by patterning openings in a matrix array for each portion to be exposed, and selectively exposing the portion exposed from the opening of the energy beam mask to the energy beam to perform photorefraction of the portion. Forming a microlens having a size including the pixel portion for each of the pixel portions by changing the ratio. Method of manufacturing shows apparatus. 4. The pixel electrodes are arranged in a matrix array on one of the two light-transmissive insulating substrates, and a switching element connected to the pixel electrodes is arranged. Forming an array substrate by forming a light-shielding layer that covers the gap between the pixel electrodes and the switching element and has an opening that exposes each pixel portion; and forming a counter electrode on the other light-transmissive insulating substrate. And forming a counter substrate, and disposing the array substrate and the counter substrate so as to face each other with a gap between the pixel electrode and the counter electrode,
By sealing the periphery of the array substrate and the counter substrate,
A step of forming a sealed liquid crystal cell in an empty cell state, and applying a light-transmissive material on the outer surface of the light-transmissive insulating substrate of the counter substrate or on the outer surface of the light-transmissive insulating substrate. A light-transmitting material layer is formed, and on the light-transmitting material layer,
Applying a resist film having resistance to a molten salt containing metal ions, and irradiating the resist film with light from the array substrate side through the opening of the light shielding layer to expose the resist film. A step of forming an opening in the exposed region, and diffusing the metal ion in a portion of the light transmissive insulating substrate or the light transmissive material layer exposed from the opening of the resist film using a molten salt containing the metal ion. And changing the optical refractive index of the portion to form a microlens having a size including the pixel portion in each of the pixel portions, and forming an injection hole in a part of the liquid crystal cell in the empty cell state. And a step of injecting a liquid crystal composition from the injection hole so that the liquid crystal layer is enclosed and sandwiched in the liquid crystal cell. 5. Pixel electrodes are arrayed and formed in a matrix array on one of the two light-transmissive insulating substrates, and switching elements connected to the pixel electrodes are arranged, and the pixel electrodes are connected to each other. Forming a light-shielding layer having an opening for covering the gap and the switching element and exposing each pixel portion, and forming an array substrate; and forming a counter electrode on the other light-transmissive insulating substrate to form a counter substrate. And the array substrate and the counter substrate are arranged so as to face each other with a gap between the pixel electrode and the counter electrode,
By sealing the periphery of the array substrate and the counter substrate,
Forming a sealed liquid crystal cell in an empty cell state, and using a light-transmissive material on the outer surface of the light-transmissive insulating substrate of the counter substrate or on the outer surface of the light-transmissive insulating substrate. A step of forming a material layer and applying a resist film having a shielding property against projection of metal ions on the light transmissive material layer; and opening the light shielding layer from the array substrate side to the resist film. Exposing the resist film by irradiating light therethrough to form an opening in the exposed region; and the metal ion in a portion of the light transmissive insulating substrate or the light transmissive material layer exposed from the opening of the resist film. And changing the optical refractive index of the portion to form a microlens having a size including the pixel portion in each of the pixel portions, and forming an injection hole in a part of the liquid crystal cell in the empty cell state. Liquid crystal set from the injection hole A method for manufacturing a liquid crystal display device, comprising the steps of injecting a composition and enclosing and sandwiching the composition as a liquid crystal layer in the liquid crystal cell. 6. The method for manufacturing a liquid crystal display device according to claim 3, wherein a cross section of an edge portion of a pattern of the energy beam mask, the resist film, or the heat storage film is formed before the step of forming the microlens. A method of manufacturing a liquid crystal display device, comprising a step of forming a shape into a taper shape.