JP2003279949A - Manufacturing method for substrate with recessed part for microlens, substrate with recessed part for microlens, microlens substrate, opposed substrate for liquid crystal panel, liquid crystal panel and projection type display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a substrate with a recessed part for a microlens coping with an aspherical lens. <P>SOLUTION: The substrate with the recessed part for the microlens is manufactured through a process of forming a first mask layer 6 on the surface of a glass substrate 5, a process of forming a first opening 61 on the first mask layer 6, a process of forming a first recessed part 31 on the glass substrate 5 by wet etching, a process of removing the first mask layer 6, a process of forming a second mask layer 63 on the surface of the glass substrate 5, a process of forming a third opening 631 on the second mask layer 63, a process of forming the recessed part on the glass substrate 5 by wet etching, and a process of removing the second mask layer 63. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a substrate with concave portions for microlenses, in which a large number of concave portions for microlenses are formed on a substrate, a substrate with concave portions for microlenses,
The present invention relates to a microlens substrate, a counter substrate for a liquid crystal panel, a liquid crystal panel, and a projection type display device.

[0002]

2. Description of the Related Art A projection type display device for projecting an image on a screen is known.

In such a projection type display device, a liquid crystal panel (liquid crystal optical shutter) is mainly used for image formation.

In this liquid crystal panel, for example, a liquid crystal drive substrate (TFT substrate) having a thin film transistor (TFT) for controlling each pixel and a pixel electrode, and a counter substrate for a liquid crystal panel having a black matrix, a common electrode and the like are provided. It is configured to be bonded via a liquid crystal layer.

In the liquid crystal panel (TFT liquid crystal panel) having such a structure, since the black matrix is formed in a portion other than the pixel portion of the counter substrate for the liquid crystal panel, the area of light passing through the liquid crystal panel is limited. To be done. Therefore, the light transmittance is reduced.

In order to increase the light transmittance, it is known that a counter substrate for a liquid crystal panel is provided with a large number of minute microlenses at positions corresponding to respective pixels. As a result, the light transmitted through the counter substrate for the liquid crystal panel is condensed in the openings formed in the black matrix, and the light transmittance is increased.

As a method of forming a recess in a substrate for forming such a microlens, for example, a technique disclosed in Japanese Patent Laid-Open No. 9-101401 is known.

However, in such a technique, from the substrate in which the concave portion for forming the microlens is formed, to the counter substrate for the liquid crystal panel, which has excellent characteristics, particularly high light transmittance,
Consequently, it is difficult to properly manufacture the liquid crystal panel.

Further, with the method using isotropic etching (wet etching), only a hemispherical lens can be formed. With a lens having a small radius of curvature such as a microlens, spherical aberration was large, and projection transmittance and projection contrast ratio could not be sufficiently obtained.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a substrate with concave portions for microlenses capable of forming aspherical microlenses with suppressed spherical aberration,
A method of manufacturing a substrate with concave portions for microlenses, a substrate with concave portions for microlenses, a microlens substrate, a counter substrate for a liquid crystal panel, a liquid crystal panel, and a projection display device.

[0011]

Such an object is achieved by the present invention described in (1) to (22) below.

(1) A mask having openings in a predetermined pattern is formed on a substrate, and then wet etching is performed using the mask to form a large number of concave portions for microlenses on the substrate, and then the mask is formed. A method of manufacturing a substrate with a concave portion for a microlens, the method comprising: forming an aspherical concave portion for a microlens by performing wet etching in multiple steps while expanding the size of the opening of the mask. And a method for manufacturing a substrate with concave portions for microlenses.

(2) The substrate with concave portions for a microlens according to (1), wherein the mask is formed by laminating a plurality of mask layers having different sizes of openings so that the openings are gradually increased. Manufacturing method.

(3) The method for manufacturing a substrate with concave portions for microlenses according to (2), wherein one of the openings of the mask layers adjacent to each other of the plurality of mask layers is included in the other.

(4) The method for manufacturing a substrate with concave portions for microlenses according to (2) or (3), wherein the openings of the plurality of mask layers are arranged concentrically.

(5) The method for manufacturing a substrate with concave portions for microlenses according to any one of (1) to (4), wherein the mask is made of polycrystalline silicon.

(6) The mask is formed on the substrate and has an annular first mask layer having a higher etching rate for an etching solution than the substrate, and an opening on the inner peripheral side of the first mask layer. Having the substrate and the first
The method for producing a substrate with concave portions for microlenses according to (1) above, further comprising a second mask layer formed over the mask layer.

(7) When the etching rate of the first mask layer to the etching solution is a and the etching rate of the substrate to the etching solution is b, the etching rate ratio a / b is 1.1 or more. The method for manufacturing a substrate with concave portions for microlenses according to (6) above.

(8) The opening of the second mask layer is arranged in the central portion of the first mask layer (6).
Alternatively, the method for manufacturing a substrate with concave portions for a microlens according to (7).

(9) The method for manufacturing a substrate with concave portions for a microlens according to any one of (6) to (8), wherein a plurality of the first mask layers are provided.

(10) One of the adjacent first mask layers of the plurality of first mask layers is included in the other and is spaced apart from the other of the first mask layers. Of manufacturing a printed circuit board.

(11) The plurality of first mask layers are
The method for producing a substrate with concave portions for microlenses according to (9) or (10), which is arranged concentrically.

(12) The method for manufacturing a substrate with concave portions for microlenses according to any one of the above (1) to (11), wherein after the mask is removed, wet etching is further performed on the entire surface.

(13) The method for manufacturing a substrate with concave portions for microlenses according to any one of the above (1) to (12), wherein the substrate is a quartz glass substrate.

(14) A substrate with concave portions for microlenses, which is manufactured by the method for manufacturing a substrate with concave portions for microlenses according to any one of (1) to (13) above.

(15) A microlens substrate manufactured by using the substrate with concave portions for microlens according to the above (14) and having a plurality of microlenses.

(16) The microlens substrate according to the above (15), wherein the microlens is a biconvex microlens.

(17) A plurality of first microlens recessed substrates having a plurality of aspherical first microlens recesses and a plurality of aspherical second microlens recesses described in (14) above. The second substrate having the concave portion for microlenses is bonded to the first concave portion for microlens and the concave portion for second microlens via a resin so as to face each other, and thus the first substrate A microlens substrate comprising a biconvex microlens formed between a substrate with concave portions for microlens and the second substrate with concave portions for microlens.

(18) A counter substrate for a liquid crystal panel comprising the microlens substrate according to any one of (14) to (17).

(19) A liquid crystal panel comprising the counter substrate for a liquid crystal panel described in (18) above.

(20) A liquid crystal drive substrate having a pixel electrode, the liquid crystal panel counter substrate described in (18) bonded to the liquid crystal drive substrate, the liquid crystal drive substrate and the liquid crystal panel counter substrate. And a liquid crystal enclosed in the void of the liquid crystal panel.

(21) The liquid crystal panel according to the above (20), wherein the liquid crystal driving substrate is a TFT substrate.

(22) A projection display device comprising the liquid crystal panel according to any one of (18) to (21).

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail with reference to the preferred embodiments shown in the accompanying drawings.

The substrate with concave portions for microlens and the microlens substrate of the present invention include both an individual substrate and a wafer, respectively.

FIGS. 1 to 7 are schematic vertical sectional views showing a method of manufacturing a substrate with concave portions for microlenses of the present invention, and FIG.
FIG. 9 is a schematic vertical sectional view showing a method for manufacturing a counter substrate for a liquid crystal panel of the present invention, FIG. 9 is a schematic vertical sectional view showing a counter substrate for a liquid crystal panel of the present invention, and FIG. It is a typical top view which shows the board | substrate with the recessed part for microlenses.

As shown in FIG. 9, the counter substrate 1 for a liquid crystal panel includes a substrate 2 having concave portions for microlenses, and a transparent resin layer 14 having a predetermined refractive index on the substrate 2 having concave portions for microlenses. Cover glass 13 bonded together
And a black matrix 11 formed on the cover glass 13 and having a plurality (a large number) of openings 111.
And a transparent conductive film 12 formed on the cover glass 13 so as to cover the black matrix 11. The substrate 2 with concave portions for microlenses is composed of a glass substrate 5 having a plurality (a large number) of aspherical concave portions 3 (concave portions for microlenses) formed on its surface. Further, in the resin layer 14, the substrate 2 with concave portions for microlenses
The aspherical microlens 8 is formed of the resin with which the concave portion 3 is filled.

In the counter substrate 1 for liquid crystal panel, the black matrix 11 having a light shielding function is provided so as to correspond to the position of the microlens 8. Specifically, the black matrix 11 is provided so that the optical axis Q of the microlens 8 passes through the opening 111 formed in the black matrix 11. Therefore, in the counter substrate 1 for the liquid crystal panel, the incident light L incident from the surface facing the black matrix 11 is condensed by the microlens 8 and passes through the opening 111 of the black matrix 11. The transparent conductive film 12 is an electrode having transparency and transmits light. Therefore, when the incident light L passes through the counter substrate 1 for the liquid crystal panel, the light amount is prevented from being greatly attenuated. That is, the counter substrate 1 for liquid crystal panel has a high light transmittance.

In this counter substrate 1 for liquid crystal panel, one microlens 8 and one opening 111 of the black matrix 11 correspond to one pixel.

The substrate 2 with concave portions for microlenses
May have other components such as an antireflection layer.

Prior to describing the method of manufacturing a microlens substrate or a counter substrate for a liquid crystal panel of the present invention, first, FIGS. 1 to 4 will be referred to regarding the method of manufacturing a substrate with concave portions for a microlens of the present invention. While explaining.

In the present invention, recesses for aspherical lenses (recesses for aspherical microlenses) are formed by performing wet etching in multiple stages using a plurality of masks having different opening sizes. Although a large number of concave portions for microlenses are actually formed on the substrate, a case of forming one concave portion for microlenses will be described here as an example for easy understanding of the description.

First, the glass substrate 5 is prepared when manufacturing the substrate 2 having concave portions for microlenses.

As the glass substrate 5, a glass substrate having a uniform thickness and free from bending and scratches is preferably used. Further, the glass substrate 5 is preferably one whose surface is cleaned by washing or the like.

If the manufactured microlens recessed substrate 2 is used for manufacturing a liquid crystal panel and the liquid crystal panel has a glass substrate other than the glass substrate 5, the coefficient of thermal expansion of the glass substrate 5 is: It is preferable that the coefficient of thermal expansion of the other glass substrate of the liquid crystal panel is substantially equal. In this way, if the glass substrate 5 and other glass substrates of the liquid crystal panel have almost the same thermal expansion coefficient, the resulting liquid crystal panel has different thermal expansion coefficients when the temperature changes. Warpage and bending are prevented.

From this point of view, it is preferable that the glass substrate 5 and the other glass substrate of the liquid crystal panel are made of the same material. As a result, warpage, flexure, etc. due to the difference in the coefficient of thermal expansion when the temperature changes can be effectively prevented.

In particular, when the manufactured microlens recessed substrate 2 is used for manufacturing a high temperature polysilicon TFT liquid crystal panel, the glass substrate 5 is preferably made of quartz glass. The TFT liquid crystal panel has a TFT substrate as a liquid crystal driving substrate. Such TFT
For the substrate, quartz glass whose characteristics are less likely to change depending on the environment during manufacturing is preferably used. For this reason, in response to this, by forming the glass substrate 5 with quartz glass, TF excellent in stability, which is unlikely to cause warping, bending, etc.
A T liquid crystal panel can be obtained.

Although the thickness of the glass substrate 5 varies depending on various conditions such as the material forming the glass substrate 5 and the refractive index, it is preferably about 0.3 to 3 mm, more preferably about 0.5 to 2 mm. . When the thickness is within this range, it is possible to obtain a compact substrate 2 with concave portions for microlenses having necessary optical characteristics.

<1> First, as shown in FIG. 1A, the first mask layer 6 is formed on the glass substrate 5. Also,
At the same time, the back surface of the glass substrate 5 (first mask layer 6
The back surface protective layer 69 is formed on the surface opposite to the surface on which the layer is formed. Of course, the first mask layer 6 and the back surface protection layer 69 can be simultaneously formed by using, for example, the CVD method or the like.

The first mask layer 6 is formed in the step <described later.
Those having resistance to wet etching in 4> are preferable.

From this point of view, the material for forming the first mask layer 6 is, for example, polycrystalline silicon (polysilicon), amorphous silicon, Au / C.
Examples thereof include metals such as r, Au / Ti, Pt / Cr, Pt / Ti, and SiC, and silicon nitride.

Of these, polycrystalline silicon is particularly preferable as the material for forming the first mask layer 6. When the first mask layer 6 is made of polycrystalline silicon, a dense layer can be formed on the surface of the glass substrate 5. Therefore, defects such as pinholes are unlikely to occur in the first mask layer 6. Further, polycrystalline silicon has high adhesion to glass. Therefore, in the step <4> described later, the glass substrate 5
On the other hand, when wet etching is performed to form a microlens, the etching liquid is less likely to enter an unnecessary portion, and an ideal lens shape can be formed. Therefore, by forming the first mask layer 6 from polycrystalline silicon, it is possible to obtain the high-performance substrate 2 with concave portions for microlenses with a high yield.

The thickness of the first mask layer 6 varies depending on the material forming the mask layer 6, but is 0.01 to 0.01 when the first mask layer 6 is made of polycrystalline silicon.
The thickness is preferably about 10 μm, more preferably about 0.2 to 1 μm. When the thickness is less than the lower limit value of this range, the masked portion of the glass substrate 5 may not be sufficiently protected when performing wet etching in the step <4> described later, and when the thickness exceeds the upper limit value, The mask layer 6 may be easily peeled off due to the internal stress of the first mask layer 6.

When the first mask layer 6 is made of polycrystalline silicon, the first mask layer 6 can be preferably formed by, for example, a chemical vapor deposition method (CVD method). This is because the chemical vapor deposition method allows a monosilane gas (SiH ₄ ) to react on the surface of the glass substrate 5 to form a polycrystalline silicon film. This is because it is possible to effectively suppress the occurrence of defects such as pinholes that are likely to occur in the case of doing, and to form a dense and cohesive film.

When the first mask layer 6 made of polycrystalline silicon is formed by the CVD method, the temperature at the time of forming the first mask layer 6 is not particularly limited, but is preferably about 300 to 800 ° C., 400 More preferably, the temperature is about 700 ° C.
The pressure at the time of forming the first mask layer 6 is not particularly limited, but is preferably about 30 to 160 Pa, and 50 to 10 Pa.
About 0 Pa is more preferable. The supply rate of the gas that is a raw material for forming polycrystalline silicon such as SiH ₄ is not particularly limited, but is preferably about 10 to 500 mL / min, more preferably about 40 to 400 mL / min.
When the conditions for forming the layer of polycrystalline silicon are within such a range, the first mask layer 6 can be preferably formed.

The back surface protective layer 69 is for protecting the back surface of the glass substrate 5 in the subsequent steps. The back surface protective layer 69 suitably prevents the back surface of the glass substrate 5 from being eroded and deteriorated. The back surface protective layer 69 is made of, for example, the same material as the mask layer 6. Therefore, the back surface protective layer 69 can be provided at the same time as the mask layer 6 is formed, similarly to the mask layer 6.

<2> Next, as shown in FIG. 1B, the first opening 61 and the second opening 6 are formed in the first mask layer 6.
Form 2. The formation of the first opening 61 and the second opening 62 is performed, for example, by applying a resist (eg, photoresist) corresponding to the first opening 61 and the second opening 62 on the first mask layer 6. Then, a second mask is further provided on the first mask layer 6, and then the first mask layer 6 in a portion not masked by the second mask is removed.
Then, it can be performed by removing the second mask.

The removal of the first mask layer 6 can be performed by dry etching with CF gas, chlorine gas, or the like, when the first mask layer 6 is made of polycrystalline silicon, hydrofluoric acid + nitric acid aqueous solution. Alternatively, it can be performed by immersion in an exfoliating solution such as an alkaline aqueous solution (wet etching).

Here, in the illustrated example, the shapes of the first opening 61 of the first mask layer 6 and the third opening 631 of the second mask layer 63 which will be described later are circular, respectively. It goes without saying that it is not limited.

<3> Next, as shown in FIG. 1C, a portion of the first mask layer 6 where the alignment mark 4 is to be formed.
The protective layer 7 is formed thereon.

This protective layer 7 corresponds to the shape of the alignment mark 4. The protective layer 7 can be directly formed not only on the mask layer 6 but also on the glass substrate 5. For example, as shown in FIG. 1C, the second opening 62
May be covered with a protective layer 7.

The protective layer 7 preferably has resistance to the etching liquid in the step <4> described below and the removal of the first mask layer 6 in the step <5> described below. As a result, etching of the first mask layer 6 in the portion protected by the protective layer 7 is prevented, and the shape of the alignment mark 4 can be accurately formed. In addition, the protective layer 7 is
It is preferably composed of a thin film. When the protective layer 7 is composed of a thin film, the step <4> and the step <to be described later are performed.
8> makes it easy to handle the glass substrate 5, and
The removal of the protective layer 7 becomes easy in the step <9> described later.

From this point of view, the protective layer 7 is, for example,
Au / Cr, Au / Ti, Pt / Cr, Pt / Ti, S
It is preferably composed of a metal such as iC, a silicon compound such as silicon nitride, a resist such as a negative resist, and a tape.

The protective layer 7 is formed of a thin film corresponding to the shape of the alignment mark 4 at the portion where the alignment mark 4 is to be formed by a vapor deposition method such as vapor deposition (mask vapor deposition), sputtering (mask sputtering). It can be formed by forming a film.

The protective layer 7 is formed on the entire glass substrate 5.
It may be formed by forming a film so as to cover the mask layer 6, then patterning a resist corresponding to the shape of the alignment mark 4 in a portion where the alignment mark 4 is formed, and then performing etching or the like.

Further, the protective layer 7 may be formed, for example, by attaching a tape or the like corresponding to the shape of the alignment mark 4 to the portion where the alignment mark 4 is to be formed.

<4> Then, the glass substrate 5 is wet-etched using the first mask layer 6 to form the first recess 31 as shown in FIG. 2D. At this time, the glass substrate 5 is a portion where the first mask layer 6 and the protective layer 7 are not present, that is, the first opening 61.
More etched. Therefore, the first recess 31 is formed in the portion where the first opening 61 is provided.

If the wet etching method is used, the first recess 31 can be preferably formed. In the case of performing the etching by the wet etching method, if the etching solution containing hydrofluoric acid (hydrofluoric acid-based etching solution) is used, the glass substrate 5 can be selectively etched, and the recess 3 can be preferably formed. You can

In addition, wet etching can perform processing with a simpler apparatus than dry etching, and can perform processing on many substrates at once. Thereby, the productivity is improved, and the substrate 2 with concave portions for microlenses can be provided at a low cost.

<5> Next, as shown in FIG. 2E, the first mask layer 6 is removed. When the first mask layer 6 and the like are made of polycrystalline silicon, for example, CF gas,
It can be performed by dry etching with a chlorine-based gas or the like, immersion in a stripping solution such as a hydrofluoric acid + nitric acid aqueous solution, or an alkaline aqueous solution (wet etching). At this time, since the portion where the protective layer 7 is formed is protected by the protective layer 7, the first mask layer 6 is not removed and remains on the glass substrate 5.

<6> Next, after the first mask layer 6 is removed, as shown in FIG. 2F, a third recess larger than the first opening 61 is formed on the first recess 31. The second mask layer 63 having the opening 631 is formed concentrically with the first opening 61.

As the material of the second mask layer 63, the same material as the above-mentioned first mask layer 6 can be used. Further, the formation of the second mask layer 63 and the formation of the third opening 631 in the second mask layer 63 are performed by forming the first mask layer 6 and the first mask layer 6 described above. It can be performed in the same manner as the formation of the first opening 61.

<7> Then, the glass substrate 5 is wet-etched using the second mask layer 63 to form the recess 3 as shown in FIGS. 3 (g) and 3 (h). Here, of the concave portions 3 formed by the second etching, the first concave portion 3 is formed near the center, that is, in advance.
The radius of curvature r ₁ of the portion where 1 is formed becomes large, and the radius of curvature r ₂ near the peripheral edge becomes small. However, since the initial hole gradually becomes larger and the center of etching moves to the peripheral portion, the radius of curvature gradually increases toward the peripheral portion. The outermost peripheral portion having a small radius of curvature overlaps with the adjacent lens and almost disappears. As a result, this concave portion 3 becomes a concave portion suitable for an aspherical lens.

In addition, in the boundary portion of the curved surfaces having different curvatures,
Although a convex portion is generated due to the difference in curvature, it tends to be smooth due to the characteristics of wet etching. However, it is preferable to smooth the entire curved surface by performing wet etching after removing the second mask layer 63 in the step <8> described later.

<8> Next, as shown in FIG. 3H, the second mask layer 63 is removed. At this time, the back surface protection layer 69 is also removed together with the removal of the second mask layer 63.

<9> Next, the protective layer 7 is removed. Although this depends on the constituent material of the protective layer 7, for example, the protective layer 7
When Au is composed of Au / Cr or the like, it can be performed by wet etching using a mixed solution of hydrochloric acid and nitric acid as a stripping solution. When the protective layer 7 is made of silicon nitride or the like, the protective layer 7 can be removed by wet etching using phosphoric acid or the like as a stripping solution. When the protective layer 7 is composed of a tape or the like, the protective layer 7 can be removed by peeling off the tape.
Can be removed. As a result, as shown in FIG. 3I, the portion of the first mask layer 6 protected by the protective layer 7 remains as the alignment mark 4.

As described above, as shown in FIG. 3I, the aspherical concave portion 3 is formed on the glass substrate 5. In reality, as shown in FIG. 10, many recesses 3 are formed on the glass substrate 5.

As described above, by performing wet etching in multiple stages using a plurality of masks having different opening sizes, it is possible to make the radius of curvature different between the central portion and the peripheral portion of the recess 3. It is possible to form the substrate 2 with concave portions for microlenses, which has concave portions for spherical lenses.

The substrate 2 with concave portions for microlenses is
Since the concave portion for the aspherical lens is provided, the spherical aberration is suppressed in the aspherical lens configured using the substrate 2 with concave portions for the microlens. A microlens substrate or a counter substrate for a liquid crystal panel using the substrate with concave portions for a microlens of the present invention has high light utilization efficiency and excellent optical characteristics.

Further, in the above description, the case where the etching is performed in two steps using the two masks having different opening sizes has been described as an example, but the number of times is not limited to this, and the number of times is three.
It may be more than three times (three stages). If the number of masks to be used, that is, the number of wet etchings performed while enlarging the opening of the mask is increased, a smoother lens concave portion can be formed.

In the above description, the glass substrate 5 is used as the substrate of the recessed substrate 2 for microlenses. However, in the present invention, the constituent material of the substrate is not limited to glass and, for example, metal. It may be a resin or the like.

The alignment mark 4 (see FIG. 10) formed on the substrate 2 with concave portions for microlenses is used as a positioning index when the counter substrate 1 for liquid crystal panel is manufactured.

The formation position of the alignment mark 4 is not particularly limited, but the alignment mark 4 can be formed outside the region where the recess 3 is formed, as shown in FIG. 10, for example.

The alignment marks 4 are preferably provided at a plurality of positions on the substrate 2 having concave portions for microlenses.
In particular, it is preferable to provide the alignment marks 4 at a plurality of positions at the corners of the substrate 2 with concave portions for microlenses. As a result, the positioning can be performed more easily.

FIG. 10 shows an example in which the alignment mark 4 has a cross shape. The shape of the alignment mark 4 is not particularly limited, but as shown in FIG. 5, it is preferable that the alignment mark 4 has a corner portion 41 that forms a corner. When the alignment mark 4 has the corner portion 41 as described above, the positioning can be performed more accurately.

Further, as shown in FIG. 10, it is preferable that the alignment mark 4 has a mark (a circular second opening 62 in FIG. 10) indicating its central portion. Thereby, the positioning accuracy can be further improved.

In the method described above, the protective layer 7 is formed on the glass substrate 5 (see the above step <3>) and then the recess 3 is formed (see the above step <4>). The concave portion 3 is formed before forming the protective layer 7
May be formed. That is, the protective layer 7 may be formed after forming the concave portion 3.

Further, in the above-mentioned method, the alignment mark is provided by forming the layer on the glass substrate 5, but the alignment mark may not be formed on the glass substrate 5 as a layer. For example, a recess having a shape different from that of the recess 3 may be provided on the glass substrate 5 as an alignment mark. Such a recess forms, for example, the second opening 62 so as to correspond to the shape of the recess (alignment mark) in the above step <2>, and then,
The glass substrate 5 is etched without forming the protective layer 7 (without performing the above step <3>) (the above step <4>).
Can be provided.

However, when the alignment mark 4 is formed as described above, the mask layer 6 forming the alignment mark 4 and the glass substrate 5 in the vicinity of the alignment mark 4 are prevented from being corroded.
In particular, it becomes easy to accurately form the corner portion 41, and the accuracy in positioning can be improved.

As described above, by forming the alignment mark 4 in the middle of the step of forming the concave portion 3 by etching, the alignment mark 4 can be formed without significantly increasing the number of steps.

This alignment mark 4 can be used for various positionings when assembling various things using the substrate 2 with concave portions for microlenses. For example,
When the counter substrate 1 for a liquid crystal panel having the black matrix 11 is manufactured using the substrate 2 with concave portions for microlenses, the black matrix 11 corresponds to the concave portions 3, that is, the microlenses 8 using the alignment mark 4 as an index. Can be positioned in position.

In the above description, the case where the mask formation and the peeling are repeated every time wet etching is performed has been described as an example, but the configuration and formation method of the mask used in the present invention are not limited to this. For example, a method of stacking a plurality of masks having different opening sizes, a method of alternately forming two kinds of masks having different etching rates in a concentric pattern, and the like can be given.

Hereinafter, these methods will be described. Although the description of the protective layer 7 and the back surface protective layer 69 for forming the alignment mark 4 is omitted in the following description, they can be formed by the same method as described above.

First, referring to FIGS. 4 to 5, a method of stacking a plurality of masks and performing multi-step wet etching will be described.
Will be described with reference to. Here, a case will be described as an example in which three masks each having a different opening size are formed in layers and wet etching is performed in three steps.

<A1> First, as shown in FIG.
On the glass substrate 5, substantially circular openings 61 of different sizes are formed.
First mask layer 6 having 1, 612 and 613 respectively
41, the second mask layer 642, and the third mask layer 643 are concentrically laminated in this order to form a laminated mask 64.

At this time, the first mask layer 641, the second mask layer 642, and the third mask layer 643 are respectively
It is formed to have the same thickness.

Further, the size of the opening of each mask layer increases in the order of the opening 611, the opening 612, and the opening 613, and one of the adjacent openings is included in the other. That is, the opening 611 is included in the opening 612, and the opening 612 is included in the opening 613.

As the materials and forming methods of the first to third mask layers 641 to 643 having the openings 611 to 613, conventionally known materials and forming methods can be adopted including the above-mentioned materials and forming methods. Specifically, each mask layer may be formed by, for example, a photolithography technique.

Needless to say, the shapes of the openings 611 to 613 are not limited to circular shapes.

<A2> Then, as shown in FIG. 4K, the glass substrate 5 is wet-etched using the laminated mask 64 to form the first recess 32. At this time, the glass substrate 5 is etched from the portion not covered with the laminated mask 64, that is, the portion of the opening 611.

<A3> Next, as shown in FIG. 4L, the first mask layer 641 exposed from the opening 612 of the second mask layer 642 is removed, and the opening is opened to the second mask layer. The layer 642 is expanded to the size of the opening 612.

Specifically, the entire laminated mask 64 is etched by the thickness of the first mask layer 641. As a result, the first mask layer 641 exposed from the opening 612 of the second mask layer 642 is removed, whereby the opening of the laminated mask 64 is changed to the opening 612 of the second mask layer 642. It will spread to the size.

Since the first to third mask layers have the same thickness, the third mask layer 6 is simultaneously formed at this time.
43 is removed. Further, the second mask layer 642 exposed from the opening 613 of the third mask layer 643 is also removed. As a result, the opening 612 of the second mask layer 642 is formed.
However, it is expanded to the size of the opening 613 which the third mask layer 643 had.

<A4> Then, the glass substrate 5 is wet-etched using the laminated mask 64,
As shown in FIG. 5 (m), the second recess 33 is formed.
At this time, in the second concave portion 33, the radius of curvature near the central portion is large and the radius of curvature near the peripheral edge is small.

<A5> Next, as shown in FIG. 5N, the first mask layer 641 exposed from the opening 612 of the second mask layer 642 is removed, and the opening is opened to the third mask layer. Expand to the size of the opening 613 that the layer had.

Specifically, the entire laminated mask 64 is etched by the thickness of the first mask layer 641. As a result, the first mask layer 641 exposed from the opening 612 of the second mask layer 642 is removed, whereby the opening of the laminated mask 64 becomes the opening 61 of the second mask layer 642.
The size of the second mask layer 643 is expanded to the size of 2, that is, the size of the opening 613 which the third mask layer 643 originally has.
At this time, the second mask layer 642 is also removed at the same time.

<A6> Then, the glass substrate 5 is wet-etched using the laminated mask 64,
As shown in FIG. 5 (o), the recess 3 is formed. The radius of curvature of the concave portion 3 formed in this manner near the central portion is large, and the radius of curvature is small toward the peripheral portion.

As described above, the aspherical lens concave portion is formed. Finally, it is preferable to remove the first mask layer 641 and then perform wet etching to smooth the entire curved surface.

According to the method using the laminated mask 64, there is no step of forming a mask layer on the way, so that the concave portion 3 can be formed in the glass substrate 5 more easily and quickly.

In the present invention, two masks each having a different opening size may be laminated and wet-etched in two steps, or four or more masks each having a different opening size may be formed. The layers may be formed and wet etching may be performed in four or more steps.

Next, a method of performing multi-step wet etching by alternately forming two kinds of masks having different etching rates with respect to an etching solution in concentric circles,
This will be described with reference to FIGS. In addition, here
The case where wet etching is performed in three stages will be described as an example.

<B1> First, two annular first mask layers 651 and 652 of different sizes are formed on the glass substrate 5.
Are formed concentrically with a predetermined interval.

That is, the inner diameter of the first mask layer 652 is made larger than the outer diameter of the first mask layer 651, and these two first mask layers 651 and 652 are arranged concentrically.
Thereby, the two adjacent first mask layers 65 are formed.
One mask layer 651 of the first mask layer 652 is included in the other mask layer 652 and is separated from the inner circumference of the other mask layer 652.

As the method of forming the first mask layers 651 and 652, the above-described forming method and conventionally known forming methods can be adopted. Although described in detail later, the sizes of the outer peripheries of the first mask layer 651 and the first mask layer 652 are the same as the sizes of the openings of the mask during the etching in the second step and the third step, respectively. Equivalent to.

Next, as shown in FIG. 6P, a second mask layer 653 is formed over the glass substrate 5 and the first mask layers 651 and 652. Next, a substantially circular opening 614 is formed in the second mask layer 653. This opening 6
14 is formed on the inner peripheral side of the first mask layer 651, that is, in the portion corresponding to the central portion of the first mask layers 651 and 652.

As the method for forming the second mask layer 653, conventionally known forming methods can be adopted in addition to the above-described forming method.

In this manner, the inner peripheral side of the first mask layer 651, the first mask layer 651, the first mask layer 651 and the first mask layer 652, and the first mask layer 651 are formed. The second mask layer 653 is formed on the mask layer 652 and on the outer peripheral side of the first mask layer 652, respectively. In the thickness portions of the first mask layers 651 and 652, the first mask layer 651 is formed. , 652 and the second mask layer 653 are concentrically arranged alternately.

Here, the etching rates of the first mask layers 651 and 652 and the second mask layer 653 with respect to the etching liquid are largely different, and the first mask layers 651 and
The etching rate of 652 is much higher than the etching rate of the second mask layer 653.

That is, the second mask layer 653 is a portion that functions as a mask originally, and is more than the glass substrate 5 in comparison with the glass substrate 5.
The etching rate with respect to the etching solution is made small (preferably much smaller).

As the material of the second mask layer 653, conventionally known materials such as the above-mentioned materials can be used.

On the other hand, the first mask layers 651 and 652 are
As compared with the glass substrate 5, the etching rate with respect to the etching solution is set to be higher (preferably much higher).

When the etching rate of the first mask layers 651 and 652 with respect to the etching solution is a and the etching rate of the glass substrate 5 with respect to the etching solution is b, the larger the etching rate ratio a / b, the better. .

That is, the etching rate ratio a /
b is preferably 1.1 or more, more preferably 1.5 or more, and further preferably about 2 to 10.

As a result, in the later-described wet etching, when the glass substrate 5 is etched and the etching liquid comes into contact with the first mask layers 651 and 652, the first mask layers 651 and 652 are formed, respectively. It is etched and removed at a speed higher than that of the glass substrate 5, and the size of the opening of the mask reaches the size of the next stage quickly, so that the recess 3 can be formed in the glass substrate 5 with higher accuracy. .

Examples of the material forming the first mask layers 651 and 652 are metals such as Au, Pt, Cr and Ti, Au / Cr, Au / Ti, Pt / Cr and Pt / Ti. Examples include metal film laminates, oxides such as SiO ₂ , various resist materials, polyimides, acrylic resins, epoxy resins and the like. Among these, SiO ₂ sputtered film, SiO ₂ CVD film, SiO ₂ TEOS film and the like are preferable. .

The first mask layers 651 and 6 are used.
It goes without saying that the shape of each 52 is not limited to the annular shape.

<B2> Next, the glass substrate 5 is wet-etched by using the concentric mask 65 formed as described above to form the first concave portion 34 as shown in FIG. 6 (q). Form. At this time, the glass substrate 5 is
The portion not covered with the concentric mask 65, that is, the portion of the opening 614 is etched. Further, the second mask layer 653 having a low etching rate is hardly etched and functions as a mask.

<B3> Then, the etching of the glass substrate 5 progresses, and as shown in FIG. 6 (r), the first concave portion 34 becomes the first concave portion.
When it becomes larger than the inner circumference of the mask layer 651, the etching solution comes into contact with the first mask layer 651. Then, the first mask layer 651 with a high etching rate is formed.
However, it is etched at a relatively high speed. On the other hand, as described above, the second mask layer 653 having a low etching rate is hardly etched. Thus, the first mask layer 65
Due to the difference in etching rate between the first and second mask layers 653, only the first mask layer 651 is etched and removed. Then, as shown in FIG. 6 (r), a gap 651 ′ is formed between the portion where the first mask layer 651 was disposed, that is, the glass substrate 5 and the second mask 653.

Then, the etching liquid also enters this gap 651 ′, and the portion of the glass substrate 5 masked by the first mask layer 651 also begins to be etched. That is, the first
Since the mask layer 651 of is removed by etching,
This means that the opening of the concentric mask 65 is expanded to the outer peripheral portion of the first mask layer 651.

<B4> Further, the glass substrate 5 is wet-etched to form the second recess 35 as shown in FIG. 7 (s). At this time, in the second concave portion 35, the radius of curvature near the central portion becomes large and the radius of curvature near the peripheral edge becomes small.

<B5> Similarly, as the etching of the glass substrate 5 progresses, the second recess 35 becomes larger, and as shown in FIG. 7 (t), the second recess 35 becomes the first mask layer. 652
When it becomes larger than the inner circumference of the second mask layer, the etching solution comes into contact with the second mask layer 652. Then, the first mask layer 652 having a high etching rate is etched at a relatively high speed. On the other hand, as described above, the second mask layer 653 having a low etching rate is hardly etched. In this manner, only the first mask layer 652 is etched and removed, and as shown in FIG. 7T, the portion where the first mask layer 652 is arranged, that is, the glass substrate 5 and the second mask layer 652 are removed. A gap 652 ′ is formed between the mask 653 and the mask 653.

Then, the etching liquid also enters this gap 652 ′, and the glass substrate 5 in the portion masked by the first mask layer 652 also begins to be etched. That is, the first
Since the mask layer 652 of is removed by etching,
This means that the opening of the concentric mask 65 is widened to the outer peripheral portion of the first mask layer 652.

<B6> Further, the glass substrate 5 is wet-etched to form the recess 3 as shown in FIG. 7 (u). The radius of curvature of the concave portion 3 formed in this manner near the central portion is large, and the radius of curvature is small toward the peripheral portion.

As described above, the aspherical lens concave portion is formed. Finally, it is preferable that after removing the second mask layer 653, wet etching is further performed to smooth the entire curved surface.

According to the method of using the concentric mask 65, there is no step of forming the mask layer and step of removing the mask layer on the way, so that the concave portion 3 can be formed in the glass substrate 5 more easily and quickly. it can.

In the present invention, one first mask layer may be provided and wet etching may be performed in two steps, or three or more first mask layers may be provided and wet etching may be performed in four or more steps. You can go.

A method of manufacturing the microlens substrate and the liquid crystal panel counter substrate 1 using the microlens recessed substrate 2 will be described below with reference to FIG.

The microlens recessed substrate and the microlens substrate of the present invention are not limited to the counter substrate for liquid crystal panel and the liquid crystal panel described below.
It goes without saying that it can be used in various electro-optical devices such as CDs and optical communication devices, and other devices.

<10> First, as shown in FIG.
The cover glass 13 is bonded to the surface of the substrate 2 having concave portions for microlens on which the concave portions 3 are formed, with an adhesive agent.

The resin layer (adhesive layer) 14 is formed by curing (solidifying) this adhesive. Further, as a result, the resin layer 14 is provided with the microlens 8 which is made of the resin with which the concave portion 3 is filled and which functions as a convex lens.

As the adhesive, an optical adhesive having a refractive index higher than that of the glass substrate 5 (for example, n = 1.60) is preferably used.

<11> Next, as shown in FIG.
The cover glass 13 is thinned.

This can be performed by, for example, grinding, polishing, etching, etc. the cover glass 13.

The thickness of the cover glass 13 is, from the viewpoint of obtaining the counter substrate 1 for liquid crystal panel having the required optical characteristics,
10-1000 μm is preferable, and 20-150 μm
The degree is more preferable.

If the laminated cover glass 13 has the optimum thickness for the subsequent steps, this step may not be performed.

<12> Next, as shown in FIG.
The black matrix 11 having the openings 111 is formed on the cover glass 13.

At this time, the black matrix 11 is
The optical axis Q of the microlens 8 is formed so as to correspond to the position of the microlens 8, specifically, so as to pass through the opening 111 of the black matrix 11 (see FIG. 9).

The black matrix 11 is composed of, for example, a metal film of Cr, Al, Al alloy, Ni, Zn, Ti or the like, a resin layer in which carbon or titanium is dispersed, or the like. Among them, the black matrix 11 is
It is preferably composed of a Cr film or an Al alloy film. When the black matrix 11 is composed of a Cr film, it is possible to obtain the black matrix 11 having excellent light shielding properties. In addition, the black matrix 11 is Al
When it is made of an alloy film, the counter substrate 1 for a liquid crystal panel having excellent heat dissipation can be obtained.

The thickness of the black matrix 11 is preferably about 0.03 to 1.0 μm from the viewpoint of suppressing the influence on the flatness of the counter substrate 1 for liquid crystal panel.
More preferably, it is about 0.05 to 0.3 μm.

The black matrix 11 having the openings 111 formed therein can be formed, for example, as follows. First, a thin film to be the black matrix 11 is formed on the cover glass 13 by a vapor deposition method such as sputtering. Next, a resist film is formed on the thin film that becomes the black matrix 11. Next, using the alignment mark 4 as an index, the resist film is exposed so that the opening 111 of the black matrix 11 is located at a position corresponding to the microlens 8 (recess 3), and a pattern of the opening 111 is formed in the resist film. To do. Next, wet etching is performed to remove only the portion of the thin film that will become the opening 111. Next, the resist film is removed. In addition, as a stripping solution for performing the wet etching, for example, a thin film to be the black matrix 11 is A
When it is composed of an L alloy or the like, a phosphoric acid-based etching solution can be used.

The black matrix 11 having the openings 111 can be preferably formed by dry etching using chlorine gas or the like.

<13> Next, the transparent conductive film (common electrode) 12 is formed on the cover glass 13 so as to cover the black matrix 11.

As a result, it is possible to obtain the counter substrate 1 for the liquid crystal panel or the wafer on which a plurality of the counter substrates 1 for the liquid crystal panel can be taken.

The transparent conductive film 12 is made of, for example, indium tin oxide (ITO), indium oxide (IO), tin oxide (SnO ₂ ), or the like.

The thickness of the transparent conductive film 12 is 0.03 to 1 μm.
m is preferable, and 0.05 to 0.30 μm is more preferable.

The transparent conductive film 12 can be formed by sputtering, for example.

<14> Finally, the wafer of the counter substrate 1 for the liquid crystal panel is cut into a predetermined shape and size (for example, as shown by the one-dot chain line in FIG. 10) using a dicing device or the like.

As a result, the counter substrate 1 for liquid crystal panel as shown in FIG. 9 can be obtained. Since the microlens 8 included in the liquid crystal panel counter substrate 1 is an aspherical lens, spherical aberration is suppressed and excellent optical characteristics are obtained.

If it is not necessary to perform cutting, such as when the counter substrate 1 for liquid crystal panel is obtained in the above step <13>, this step may not be performed.

In the above-described embodiment, the alignment mark 4 is formed outside the region where the concave portion 3 of the substrate 2 with concave portions for microlens is formed, but the alignment mark 4 is formed inside the region where the concave portion 3 is formed. It goes without saying that it is good.

When manufacturing the counter substrate for the liquid crystal panel, for example, the transparent conductive film 12 may be directly formed on the cover glass 13 without forming the black matrix 11.

Although the alignment mark 4 is used for positioning the black matrix 11 in the above-described embodiment, when the liquid crystal panel counter substrate 1 or the wafer thereof has other components, the alignment mark 4 is used. You may use for these positioning.

Further, the alignment mark 4 is not limited to the components other than the components of the liquid crystal panel counter substrate 1, for example, the TFT.
It may be used for positioning other substrates such as a substrate (liquid crystal driving substrate).

In the description of the method for manufacturing the counter substrate 1 for the liquid crystal panel, the resin 14 is filled in the recesses 3 of the substrate 2 with the recesses for microlenses and sandwiched by the cover glass 13, and the microlenses 8 are sandwiched by the resin 14. However, the microlens substrate can also be manufactured by the 2P method (photopolymerization) using the substrate 2 with concave portions for microlenses as a mold.

A method of manufacturing a microlens substrate by the 2P method will be described below with reference to FIGS. 11 to 13.

First, as shown in FIG. 11A, a substrate 2 with concave portions for microlenses, which is manufactured by the present invention and in which concave portions 3 for microlenses are formed, is prepared. In this method, the substrate 2 with concave portions for microlenses in which the concave portions 3 are formed is used as a mold. The microlenses 8 are formed by filling the recesses 3 with resin. A release agent or the like may be applied to the inner surface of the recess 3. Then, the substrate 2 with concave portions for microlenses is installed so that, for example, the concave portions 3 are opened vertically upward.

<C1> Next, the uncured resin that will form the microlenses 8 is supplied onto the substrate 2 with concave portions for microlenses in which the concave portions 3 are formed. <C2> Next, the transparent substrate 51 is bonded to the resin and pressed and brought into close contact.

<C3> Next, the resin is cured. This curing method is appropriately selected depending on the type of resin, and examples thereof include ultraviolet irradiation, heating, electron beam irradiation and the like.

As a result, as shown in FIG. 11 (b),
The resin 141 filled in the recess 3 forms the microlens 8.

<C4> Next, as shown in FIG. 11C, the substrate 2 with concave portions for microlenses, which is a mold, is removed from the microlenses 8.

<C5> Next, as shown in FIG. 12, for example, the transparent substrate 5 is arranged so that the microlens 8 faces vertically upward.
After setting 1, the uncured resin that will form the resin layer 142 is supplied onto the microlens 8. Examples of the supply method include a coating method such as spin coating and a 2P method using a flat plate mold.

<C6> Next, as shown in FIG. 13, the glass substrate (glass layer) 52 is bonded to the resin and pressed.
After the close contact, the resin is cured to form the resin layer 142.

<C7> Thereafter, if necessary, the thickness of the glass substrate 52 may be adjusted by grinding, polishing, or the like. As a result, a microlens substrate as shown in FIG. 13 is obtained.

After that, a black matrix, a transparent conductive film and the like are formed on the glass substrate 52 in the same manner as described above to obtain a counter substrate for a liquid crystal panel.

Further, in the above description, the microlens substrate provided with the plano-convex lens (plano-convex type microlens) constituted by using one concave-lens substrate for microlenses is used. The lens substrate is not limited to this.

A microlens substrate provided with a biconvex lens (biconvex microlens) constituted by using two microlens recessed substrates will be described below.

FIG. 14 is a schematic vertical sectional view showing an embodiment of this microlens substrate.

As shown in the figure, this microlens substrate is manufactured by the present invention. The first microlens recessed substrate (first substrate) 21 and the second microlens recessed substrate are manufactured. It has a (second substrate) 22, a resin layer 14, a microlens 8 and a spacer 9.

First substrate 21 with concave portions for microlenses
Is a plurality (a large number) of first concave surfaces (lens curved surfaces) having an aspherical surface on a first glass substrate (first transparent substrate) 53.
The concave portion (microlens concave portion) 36 and the first alignment mark 42 are formed.

Second recessed substrate 22 for microlenses
Is a plurality (a large number) of second glass substrates (second transparent substrates) 54 each having an aspherical concave curved surface (lens curved surface) on the second glass substrate (second transparent substrate) 54.
The concave portion (microlens concave portion) 37 and the second alignment mark 43 are formed.

The microlens substrate is the first
The micro-lens recessed substrate 21 and the second micro-lens recessed substrate 22 of FIG.
Resin layer (adhesive layer) 1 so as to face the concave portion 37 of
It is configured to be joined via 4. Further, in this microlens substrate, the first substrate 21 with concave portions for microlens and the second substrate 22 with concave portions for microlens are used.
Between the first concave portion 36 and the second concave portion 37, the microlens 8 made of an aspherical biconvex lens is constituted by the resin filled between the first concave portion 36 and the second concave portion 37.

This microlens substrate has two regions,
It has an effective lens area 99 and an ineffective lens area 100. The effective lens region 99 is a region where the microlens 8 formed of the resin filled in the first concave portion 36 and the second concave portion 37 is effectively used as a microlens during use. On the other hand, ineffective lens area 1
00 means a region other than the effective lens region 99.

In such a microlens substrate, for example, the light L is made incident from the first microlens recessed substrate 21 side, and the second microlens recessed substrate 2 is provided.
The light L is emitted from the second side and used.

If the microlens 8 is composed of a convex lens like this microlens substrate, the microlens 8
Aberration (particularly spherical aberration) is further reduced. For this reason,
The incident light L incident not only in the vicinity of the central portion of the microlens 8 but also in the vicinity of the edge portion of the microlens 8 is also suitably condensed by the microlens 8. That is, the light use efficiency of the microlens 8 is high. Therefore, this microlens substrate can emit the emitted light L having high brightness.

Moreover, when the aberration of the microlens 8 is reduced, it is possible to preferably prevent the emitted light from being emitted in a direction largely deviated from the optical axis of the microlens 8. Therefore, when the microlens substrate is used for a liquid crystal panel, it is possible to preferably prevent the emitted light that has passed through the microlens 8 from entering the adjacent pixels.
That is, crosstalk between pixels is prevented. Therefore, when an image is formed using a liquid crystal panel equipped with this microlens substrate, the brightness of black becomes extremely low.

The microlens substrate having the above-described structure has such advantages. Therefore, when an image is formed using a liquid crystal panel equipped with the microlens substrate, black is darker and white is brighter. Become. Therefore, in the liquid crystal panel including the microlens substrate, a high contrast ratio can be obtained, and a more beautiful image can be formed.

The microlens substrate as described above can be manufactured, for example, as follows. Hereinafter, the manufacturing method of the microlens substrate will be described with reference to FIGS.

When manufacturing a microlens substrate, first, the first microlens recessed substrate 21 and the second microlens recessed substrate 22 manufactured by the present invention are prepared.

Second substrate 22 with concave portions for microlenses
At least one of the area of the openings formed in the mask and the etching conditions (eg, etching time, etching temperature, composition of etching solution, etc.) when manufacturing
By making the conditions different from those for manufacturing the first substrate 21 with concave portions for microlenses, the aspherical shape (for example, radius of curvature) of the first concave portions 36 and the non-spherical shape of the second concave portions 37 can be changed. The spherical shape may be different. By making the aspherical shape of the first concave portion 36 and the aspherical surface shape of the second concave portion 37 different, it is possible to effectively reduce the aberration.

<D1> First, as shown in FIG.
First recess 36 of substrate 21 with recess for microlens
An uncured resin having a predetermined refractive index (in particular, a refractive index higher than the refractive indexes of the first glass substrate 53 and the second glass substrate 54) on the surface on which is formed so as to cover at least the effective lens region 99. 143 is supplied, and the resin 143 is filled in the first recess 36. At this time, the uncured resin 144 containing the spacer 9 is supplied onto the first substrate 21 with concave portions for microlenses. The resin 144 is supplied to a site where the spacer 9 is installed, for example.

The resins 143 and 144 are preferably made of the same kind of material. Thereby, in the manufactured microlens substrate, warping, bending, etc. are preferably prevented from occurring due to the difference in the thermal expansion coefficient between the resin 143 and the resin 144.

When the resin 143 is supplied onto the first substrate 21 with concave portions for microlenses, the spacer 9 is used as the resin 14
When dispersed in 4, it becomes easy to dispose the spacers 9 uniformly. Thereby, the resin layer 14 formed
Thickness unevenness is suitably suppressed.

<D2> Next, as shown in FIG. 15, the second recessed substrate (counterpart) 22 for microlenses is set on the resin 143 and the resin 144 (second recessed substrate for microlens). 22 in close contact with the resin).

At this time, the first concave portion 36 and the second concave portion 3
The second substrate 22 with concave portions for microlenses is placed on the resin so that the second substrate 22 and the concave portion 7 face each other. Further, at this time, the second substrate 22 with concave portions for microlenses is used as the spacer 9
The second substrate 22 with concave portions for microlenses is placed on the resin so as to abut. As a result, the distance between the end faces of the first substrate 21 having concave portions for microlens and the second substrate 22 having concave portions for microlens facing each other is defined by the spacer 9. Therefore, the edge thickness and the maximum thickness of the microlens 8 are defined with high accuracy.

<D3> Next, using the first alignment mark 42 and the second alignment mark 43, the first alignment mark 42
The recess 36 and the second recess 37 are aligned with each other. As a result, the second recess 37 can be accurately positioned at a position corresponding to the first recess 36. Therefore, the shape and optical characteristics of the formed microlens 8 are closer to the design values.

<D4> Next, the resin 143 and the resin 14
4 is cured to form the resin layer 14.

As a result, the second substrate 22 with concave portions for microlenses is bonded to the first substrate 21 with concave portions for microlenses via the resin layer 14. In addition, the resin layer 14
Of the resin constituting the first concave portion 36 and the second concave portion 3
The microlenses 8 are formed by the resin filled between the microlenses 8. The resin can be cured by, for example, irradiating the resin with ultraviolet rays or an electron beam, heating the resin, or the like.

<D5> Thereafter, if necessary, as shown in FIG. 16, grinding, polishing, etc. may be performed to adjust the thickness of the second substrate 22 with concave portions for microlenses.

As a result, a microlens substrate having a biconvex lens as shown in FIG. 14 can be obtained.

Then, in the same manner as described above, the second
The counter substrate 1 for a liquid crystal panel can be obtained by forming a black matrix, a transparent conductive film, etc. on the glass substrate 54.

Next, regarding a liquid crystal panel (liquid crystal optical shutter) using the counter substrate 1 for liquid crystal panel shown in FIG.
This will be described with reference to FIG.

As shown in FIG. 17, a liquid crystal panel (TFT liquid crystal panel) 16 of the present invention includes a TFT substrate (liquid crystal driving substrate) 17, a counter substrate 1 for liquid crystal panel bonded to the TFT substrate 17, and a TFT substrate. It has a liquid crystal layer 18 made of liquid crystal sealed in a space between the liquid crystal panel 17 and the counter substrate 1 for liquid crystal panel.

The TFT substrate 17 is a substrate for driving the liquid crystal of the liquid crystal layer 18, and includes a glass substrate 171, and a large number of pixel electrodes 172 provided on the glass substrate 171.
And a large number of thin film transistors (TFTs) provided in the vicinity of the pixel electrode 172 and corresponding to each pixel electrode 172.
And 173.

In this liquid crystal panel 16, the TFT substrate 17 and the liquid crystal panel counter substrate 1 are arranged so that the transparent conductive film (common electrode) 12 of the liquid crystal panel counter substrate 1 and the pixel electrode 172 of the TFT substrate 17 face each other. And are joined at a fixed distance.

The glass substrate 171 is preferably made of quartz glass for the reasons described above.

The pixel electrode 172 is charged and discharged between the pixel electrode 172 and the transparent conductive film (common electrode) 12 to form the liquid crystal layer 18.
Drive the liquid crystal of. The pixel electrode 172 is made of, for example, the same material as the transparent conductive film 12 described above.

The thin film transistor 173 is connected to the corresponding pixel electrode 172 in the vicinity. The thin film transistor 173 is connected to a control circuit (not shown) and controls the current supplied to the pixel electrode 172. Thereby, charging / discharging of the pixel electrode 172 is controlled.

The liquid crystal layer 18 contains liquid crystal molecules (not shown), and the alignment of the liquid crystal molecules, that is, the liquid crystal, changes according to the charging / discharging of the pixel electrode 172.

In this liquid crystal panel 16, usually, one microlens 8 and one opening 111 of the black matrix 11 corresponding to the optical axis Q of the microlens 8 are provided.
One pixel electrode 172 and one thin film transistor 173 connected to the pixel electrode 172 correspond to one pixel.

Incident light L incident from the side of the substrate 2 having concave portions for microlenses passes through the glass substrate 5 and is condensed when passing through the microlenses 8, while being condensed by the resin layer 14, the cover glass 13, and the black matrix 11. Opening 111,
The transparent conductive film 12, the liquid crystal layer 18, the pixel electrode 172, and the glass substrate 171 are transmitted. At this time, since a polarizing plate (not shown) is usually arranged on the incident side of the substrate 2 with concave portions for microlenses, the incident light L is linear when it passes through the liquid crystal layer 18. It is polarized. At this time, the polarization direction of the incident light L is controlled according to the alignment state of the liquid crystal molecules of the liquid crystal layer 18. Therefore, it is possible to control the brightness of the emitted light by transmitting the incident light L transmitted through the liquid crystal panel 16 to the polarizing plate (not shown).

The polarizing plate includes, for example, a base substrate,
Composed of a polarizing base material laminated on such a base substrate,
Such a polarizing substrate is made of, for example, a resin to which a polarizing element (iodine complex, dichroic dye, etc.) is added.

As described above, the liquid crystal panel 16 has the microlenses 8, and the incident light L that has passed through the microlenses 8 is condensed and passes through the openings 111 of each black matrix 11. Moreover, the liquid crystal panel 16
As described above, the counter substrate 1 for liquid crystal panel included in the substrate 2 has the concave lens substrate 2 for microlenses (that is, the microlenses 8 formed in the concave portions 3) and the black matrix 1.
It is preferably aligned with 1. Therefore, the attenuation of the incident light L when passing through the liquid crystal panel 16, especially the black matrix 11, is suppressed. That is,
The liquid crystal panel 16 has a high light transmittance and can form a bright image with a relatively small amount of light.

In this liquid crystal panel 16, for example, after the TFT substrate 17 manufactured by a known method and the counter substrate 1 for liquid crystal panel are subjected to an alignment treatment, they are bonded to each other through a sealing material (not shown), Then, a liquid crystal is injected into the void through a sealing hole (not shown) of the void thus formed,
Then, it can be manufactured by closing the sealing hole. After that, a polarizing plate may be attached to the incident side or the emitting side of the liquid crystal panel 16 as needed.

Although the TFT substrate is used as the liquid crystal driving substrate in the liquid crystal panel 16, the TF is used as the liquid crystal driving substrate.
A liquid crystal driving substrate other than the T substrate, for example, a TFD substrate,
An STN substrate or the like may be used.

In the above-described embodiment, the alignment mark 4 is formed on the finally obtained counter substrate 1 for liquid crystal panel.
However, the alignment mark 4 is left on the counter substrate 1 for the liquid crystal panel and the alignment mark 4 is left on the liquid crystal panel 16.
It may be used for positioning when manufacturing.

A projection type display device using the liquid crystal panel 16 will be described below. FIG. 18 is a diagram schematically showing an optical system of the projection type display device of the present invention.

As shown in the figure, the projection type display device 300
Is a light source 301, an illumination optical system having a plurality of integrator lenses, a color separation optical system (light guiding optical system) having a plurality of dichroic mirrors, and a liquid crystal light valve for red (for red). (Liquid crystal shutter array)
74, a green liquid crystal light valve (liquid crystal light shutter array) 75, a blue liquid crystal light valve (liquid crystal light shutter array) 76, and a red light reflection Dichroic prism (color synthesizing optical system) 71 having a dichroic mirror surface 711 and a dichroic mirror surface 712 that reflects only blue light, and a projection lens (projection optical system) 7
2 and.

The illumination optical system also has integrator lenses 302 and 303. The color separation optics
Mirrors 304, 306, 309, dichroic mirror 305 that reflects blue light and green light (transmits only red light), dichroic mirror 307 that reflects only green light, dichroic mirror that reflects only blue light (or blue light It has a reflecting mirror) 308 and condenser lenses 310, 311, 312, 313 and 314.

The liquid crystal light valve 75 is bonded to the above-mentioned liquid crystal panel 16 on the incident surface side of the liquid crystal panel 16 (the surface side on which the substrate 2 having concave portions for microlenses is located, that is, the side opposite to the dichroic prism 71). No. 1 polarizing plate (not shown) and a second polarizing plate (not shown) bonded to the exit surface side of the liquid crystal panel 16 (the surface side facing the substrate 2 with concave portions for microlenses, that is, the dichroic prism 71 side). And). Liquid crystal light valve 74
And 76 also have the same configuration as the liquid crystal light valve 75. These liquid crystal light valves 74, 75 and 7
The liquid crystal panels 16 included in 6 are each connected to a drive circuit (not shown).

In the projection display device 300, the dichroic prism 71 and the projection lens 72 form an optical block 70. Also, this optical block 7
0 and liquid crystal light valves 74, 75 and 76 fixedly installed with respect to the dichroic prism 71,
The display unit 73 is configured.

The operation of the projection display device 300 will be described below. White light (white light flux) emitted from the light source 301
Passes through the integrator lenses 302 and 303. The light intensity (luminance distribution) of the white light is made uniform by the integrator lenses 302 and 303.

Integrator lenses 302 and 303
18 is reflected by the mirror 304 to the left side in FIG. 18, and the blue light (B) and the green light (G) of the reflected light are reflected by the dichroic mirror 305 in FIG.
8, and the red light (R) is reflected to the lower side and passes through the dichroic mirror 305.

The red light transmitted through the dichroic mirror 305 is reflected by the mirror 306 to the lower side in FIG. 18, and the reflected light is shaped by the condenser lens 310 and enters the red liquid crystal light valve 74.

The green light of the blue light and the green light reflected by the dichroic mirror 305 is reflected by the dichroic mirror 307 to the left in FIG. 18, and the blue light is transmitted through the dichroic mirror 307.

The green light reflected by the dichroic mirror 307 is shaped by the condenser lens 311 and enters the liquid crystal light valve 75 for green.

The blue light transmitted through the dichroic mirror 307 is dichroic mirror (or mirror).
18 is reflected to the left side in FIG. 18, and the reflected light is reflected to the upper side in FIG. 18 by the mirror 309. The blue light is shaped by the condenser lenses 312, 313, and 314 and enters the blue liquid crystal light valve 76.

As described above, the white light emitted from the light source 301 is color-separated into the three primary colors of red, green and blue by the color separation optical system, guided to the corresponding liquid crystal light valve and made incident.

At this time, each pixel (the thin film transistor 173 and the pixel electrode 172 connected thereto) of the liquid crystal panel 16 included in the liquid crystal light valve 74 is driven by a driving circuit (driving means) which operates based on a red image signal. , Switching control (on / off), ie modulated.

Similarly, the green light and the blue light respectively enter the liquid crystal light valves 75 and 76, and are modulated by the respective liquid crystal panels 16, whereby a green image and a blue image are formed. At this time, each pixel of the liquid crystal panel 16 included in the liquid crystal light valve 75 is switching-controlled by a drive circuit that operates based on an image signal for green, and each pixel of the liquid crystal panel 16 included in the liquid crystal light valve 76 is for blue. The switching control is performed by the drive circuit that operates based on the image signal.

As a result, the red light, the green light and the blue light are emitted from the liquid crystal light valves 74, 75 and 76, respectively.
Are modulated, and a red image, a green image, and a blue image are formed.

The image for red color formed by the liquid crystal light valve 74, that is, the red light from the liquid crystal light valve 74 enters the dichroic prism 71 from the surface 713 and is reflected by the dichroic mirror surface 711 to the left side in FIG. , Through the dichroic mirror surface 712,
The light is emitted from the emission surface 716.

The image for green formed by the liquid crystal light valve 75, that is, the liquid crystal light valve 75.
Green light from the surface enters the dichroic prism 71 from the surface 714, and the dichroic mirror surfaces 711 and 7
The light passes through each of 12 and is emitted from the emission surface 716.

The image for blue color formed by the liquid crystal light valve 76, that is, the liquid crystal light valve 76.
18 is incident on the dichroic prism 71 from the surface 715, and is reflected by the dichroic mirror surface 712 in FIG.
The light is reflected to the middle left side, passes through the dichroic mirror surface 711, and exits from the exit surface 716.

In this way, the liquid crystal light valve 74,
Light of each color from 75 and 76, that is, each image formed by the liquid crystal light valves 74, 75 and 76,
They are combined by the dichroic prism 71, thereby forming a color image. This image is displayed on the screen 3 installed at a predetermined position by the projection lens 72.
20 is projected (enlarged projection).

At this time, since the liquid crystal light valves 74, 75 and 76 are provided with the liquid crystal panel 16 as described above, the light from the light source 301 is emitted from the liquid crystal light valve 74,
Attenuation as it passes through 75 and 76 is suppressed and a bright image can be projected on the screen 320.

In the above description, the case where the microlens substrate of the present invention is used in the projection type display device provided with the counter substrate for liquid crystal panel, the liquid crystal panel and the liquid crystal light valve has been described as an example. The present invention is not limited to this, and the microlens substrate of the present invention may be used in various electro-optical devices such as CCDs and optical communication devices, organic or inorganic EL (electroluminescence) display devices, and other devices. Needless to say, it can be used for.

Further, the display device is not limited to the rear projection type display device, and the microlens substrate of the present invention can be used for the front projection type display device, for example.

[0238]

Example 1 A substrate with a concave portion for a microlens having a concave portion for an aspherical lens is manufactured as follows, and a counter substrate for a liquid crystal panel is manufactured using the substrate with a concave portion for a microlens. did.

First, a quartz glass substrate having a thickness of 1 mm was prepared as a glass substrate. This quartz glass substrate is
The surface was cleaned by immersing it in a cleaning solution (80% sulfuric acid + 20% hydrogen peroxide solution) heated to 0 ° C. for cleaning.

-1A-Next, this quartz glass substrate is
Put in a CVD furnace set at 600 ° C and 80 Pa, and add Si
H ₄ was supplied at a rate of 300 mL / min, and the CVD method was used.
A polycrystalline silicon film (first mask layer and back surface protective layer) having a thickness of 0.6 μm was formed.

-2A-Next, a resist having a pattern of microlenses and alignment marks is formed by a photoresist on the formed polycrystalline silicon film (mask layer), and then the polycrystalline silicon film (first mask) is formed. Layer) is dry-etched with CF gas, and then the resist is removed to form openings (first opening and second opening) in the polycrystalline silicon film (mask layer).
Was formed (see FIG. 1B).

-3A- Next, a polycrystalline silicon film (first
Of the mask layer) and the portion of the quartz glass substrate where the alignment mark is to be formed, by sputtering and photolithography, an Au / Cr thin film (protective layer) corresponding to the shape of the alignment mark was formed.

-4A- Next, the quartz glass substrate was subjected to first wet etching to form a large number of first concave portions on the quartz glass substrate (see FIG. 2 (d)). A hydrofluoric acid-based etching solution was used as the etching solution.

-5A- Next, dry etching using CF gas is performed to form a polycrystalline silicon film (first mask layer).
Was removed.

-6A- Next, a polycrystalline silicon film (second mask layer) having a thickness of 0.6 μm was formed on this quartz glass substrate by the same CVD method as described above.

-7A- Next, an opening (third opening) was formed in the formed polycrystalline silicon film (second mask layer) by the same photolithography technique as described above (FIG. 2).
(See (f)).

-8A-Next, the quartz glass substrate was subjected to the second wet etching to form a large number of recesses on the quartz glass substrate (see FIG. 3 (g)). A hydrofluoric acid-based etching solution was used as the etching solution.

-9A- Next, dry etching was performed using CF gas to remove the polycrystalline silicon film (second mask layer and back surface protection layer).

-10A- Next, the quartz glass substrate was immersed in a mixed solution of nitric acid and hydrochloric acid (peeling solution) to remove the Au / Cr thin film.

As a result, a wafer-shaped substrate with concave portions for microlenses was obtained in which a large number of concave portions for aspherical lenses were formed on a quartz glass substrate. At this time, a cross-shaped alignment mark having a circular opening in the center is also formed.

-11A-Next, an ultraviolet (UV) curable epoxy-based optical adhesive (refractive index 1.59) was used on the surface of the substrate having the concave portions for microlenses on which the concave portions were formed.
The cover glass was joined.

As a result, the microlenses made of the optical adhesive filled in the recesses of the recessed substrate for microlenses were formed on the resin layer made of the cured optical adhesive.

-12A- Next, the bonded cover glass is ground and polished to a thickness of 50 μm.
m.

-13A- Next, a black matrix having openings was formed on the cover glass. This was done as follows. First, 0.16 μm thick Cr was sputtered onto the cover glass.
A film was formed. Next, a resist film was formed on the Cr film. Next, using the alignment mark as an index,
Using an exposure machine, expose so that each opening of the black matrix pattern matches the optical axis of each microlens,
A black matrix pattern was formed on the resist film. Next, wet etching was performed using an aqueous solution of cerium ammonium nitrate as a stripping solution to form openings in a black matrix in the Cr film. Next, the resist film was removed. At this time, the alignment mark was used as a positioning index.

-14A-Next, an ITO film (transparent conductive film) having a thickness of 0.15 μm was formed on the cover glass by sputtering so as to cover the black matrix. As a result, a wafer including a plurality of counter substrates for liquid crystal panels was obtained.

-15A- Finally, this wafer was cut using a dicing machine to obtain a counter substrate for a liquid crystal panel. When the substrate with concave portions for microlenses is obtained as an individual substrate, the counter substrate for liquid crystal panel is also obtained as an individual substrate, and therefore it is not necessary to cut and divide the wafer.

(Embodiment 2) In the same manner as in Embodiment 1, the first
To obtain a first substrate with concave portions for microlens and a second substrate with concave portions for microlens having the second concave portion.

Then, using these two microlens recessed substrates, a counter substrate for a liquid crystal panel having a biconvex lens was manufactured as follows.

-1B- First, an uncured resin having a predetermined refractive index is supplied to the surface of the first substrate with concave portions for microlenses on which the first concave portions are formed so as to cover at least the effective lens region. Then, the resin was filled in the first recess. At this time, uncured resin containing spacers was supplied onto the first substrate with concave portions for microlenses. Here, an ultraviolet (UV) curable epoxy-based optical adhesive (refractive index 1.59) was used as the resin.

-2B- Next, a second substrate with concave portions for microlenses was placed on the resin. At this time, the second substrate with concave portions for microlens is placed on the resin so that the first concave portion and the second concave portion face each other and the second substrate with concave portion for microlenses contacts the spacer. To install.

Also, using the alignment mark, the first
The concave portions of and the second concave portions were aligned with each other.

-3B- Next, the resin was cured. As a result, the second substrate with concave portions for microlenses is bonded to the first substrate with concave portions for microlenses via the resin layer. Further, among the resins forming the resin layer, the resin filled between the first concave portion and the second concave portion forms a biconvex microlens.

Thereafter, the above steps -13A- to -15A- were performed, and a counter substrate for a liquid crystal panel was obtained in the same manner as in Example 1.

(Embodiment 3) In the manufacture of the substrate with concave portions for microlenses of Embodiment 1, as the mask, the size of the opening is gradually increased, and three polycrystalline silicon films each having a thickness of 0.6 μm are laminated. By doing so, FIG. 4 (j)
Except that the laminated mask shown in FIG. 4 was provided, and the recesses were formed by wet etching with a hydrofluoric acid-based etching solution and the polycrystalline silicon film was removed by dry etching with CF gas, alternately three times each. A substrate with concave portions for microlenses was obtained in the same manner as in Example 1.

Then, a counter substrate for a liquid crystal panel was obtained in the same manner as in Example 1 using the obtained substrate with concave portions for microlenses.

(Embodiment 4) In the same manner as in Embodiment 3, the first
To obtain a first substrate with concave portions for microlens and a second substrate with concave portions for microlens having the second concave portion.

Then, a counter substrate for a liquid crystal panel provided with a biconvex lens was manufactured in the same manner as in Example 2 using the two substrates with concave portions for microlenses.

(Fifth Embodiment) In the manufacture of the substrate with concave portions for microlenses of the first embodiment, two annular first mask layers having different sizes are formed concentrically as a mask, and further a quartz glass substrate is formed. And by forming a second mask layer over the two first mask layers,
The concentric mask shown in (p) is provided, and the recess is formed by wet etching with a hydrofluoric acid-based etching solution.
A substrate with concave portions for microlenses was obtained in the same manner as in Example 1 except that the second mask layer was removed by dry etching with F gas.

As the first mask layer, a SiO ₂ sputtered film was formed to a thickness of 0.6 μm, and as the second mask layer,
A polycrystalline silicon film was formed to a thickness of 0.6 μm.

The etching rate a of the first mask layer with respect to the etching solution is 0.5 μm / min, and the etching rate b of the quartz glass substrate with respect to the etching solution is
0.1 μm / min, and the etching rate ratio a /
b was 5.

Then, a counter substrate for a liquid crystal panel was obtained in the same manner as in Example 1 by using the obtained substrate with concave portions for microlenses.

(Embodiment 6) In the same manner as in Embodiment 5, the first
To obtain a first substrate with concave portions for microlens and a second substrate with concave portions for microlens having the second concave portion.

Then, a counter substrate for a liquid crystal panel having a biconvex lens was manufactured in the same manner as in Example 2 using the two substrates with concave portions for microlenses.

(Comparative Example) Except that wet etching was not performed in two steps but was performed in one step (the above steps -5A- to -8A- were not performed) in the production of the substrate with concave portions for microlenses. A substrate with concave portions for microlenses, in which a large number of concave portions for spherical lenses are formed, is obtained in the same manner as in Example 1, and the substrate with concave portions for microlenses is used in the same manner as in Example 1 to form a counter substrate for liquid crystal panels. Got

(Evaluation) When light was made incident on the counter substrate for liquid crystal panel obtained in Examples 1 to 6 from the substrate side having concave portions for microlenses, and light was transmitted,
The light is effectively guided to the openings of the black matrix,
It was possible to obtain a bright outgoing light.

This light transmittance is 1.7 in the liquid crystal panel counter substrate of the comparative example (spherical plano-convex lens) as compared with the liquid crystal panel counter substrate having no microlens.
While it was twice, the counter substrate for liquid crystal panel of Example 1 (aspherical plano-convex lens) was 1.82 times, and the counter substrate for liquid crystal panel of Example 2 (aspherical biconvex lens) was 1.87.
1.times., 1.85 times for the liquid crystal panel counter substrate of Example 3 (aspherical plano-convex lens), 1.90 times for the liquid crystal panel counter substrate of Example 4 (aspherical biconvex lens), and Example 5 (aspherical surface). 1.95 for a counter substrate for a liquid crystal panel (plano-convex lens)
It was confirmed that excellent transmittances were obtained, which is 2.0 times for the counter substrate for liquid crystal panel of Example 6 (aspherical biconvex lens).

(Embodiment 7) Further, using the counter substrate for liquid crystal panel obtained in the above Embodiments 1 to 6, TFT liquid crystal panels having the structure shown in FIG. 17 were assembled.

The assembled TFT liquid crystal panels are all
Like the counter substrate for a liquid crystal panel, it had a high light transmittance.

Therefore, it is easily inferred that the projection type display device using such a liquid crystal panel can project a bright image on the screen.

[0280]

As described above, according to the present invention, it is possible to easily and reliably manufacture a substrate with concave portions for microlenses corresponding to an aspherical lens whose spherical aberration is suppressed.

That is, by wet etching, it is possible to form a microlens concave portion (aspherical microlens concave portion) corresponding to an aspherical lens on the substrate, thereby reducing the spherical aberration of the microlens. (Or virtually eliminated).

Also, according to the present invention, it is possible to provide a microlens substrate, a counter substrate for a liquid crystal panel, and a liquid crystal panel which have suppressed spherical aberration, high light transmittance, and excellent optical characteristics.

Further, according to the present invention, it is possible to provide a projection type display device capable of projecting a bright image.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view showing a method for manufacturing a substrate with concave portions for microlenses of the present invention.

FIG. 2 is a schematic vertical sectional view showing a method for manufacturing a substrate with concave portions for microlenses of the present invention.

FIG. 3 is a schematic vertical sectional view showing a method for manufacturing a substrate with concave portions for microlenses of the present invention.

FIG. 4 is a schematic vertical cross-sectional view showing a second manufacturing method of the substrate with concave portions for microlenses of the present invention.

FIG. 5 is a schematic vertical sectional view showing a second manufacturing method of the substrate with concave portions for microlenses of the present invention.

FIG. 6 is a schematic vertical cross-sectional view showing a third method for manufacturing a substrate with concave portions for microlenses of the present invention.

FIG. 7 is a schematic vertical cross-sectional view showing a third manufacturing method of the substrate with concave portions for microlens of the present invention.

FIG. 8 is a schematic vertical cross-sectional view showing a method for manufacturing a counter substrate for a liquid crystal panel of the present invention.

FIG. 9 is a schematic vertical sectional view showing a counter substrate for a liquid crystal panel of the present invention.

FIG. 10 is a schematic plan view showing a substrate with concave portions for microlenses of the present invention.

FIG. 11 is a schematic vertical sectional view showing a method for manufacturing a microlens substrate of the present invention.

FIG. 12 is a schematic vertical sectional view showing a method for manufacturing a microlens substrate of the present invention.

FIG. 13 is a schematic vertical sectional view showing a microlens substrate of the present invention.

FIG. 14 is a schematic vertical sectional view showing a microlens substrate of the present invention.

FIG. 15 is a schematic vertical sectional view showing a method for manufacturing a microlens substrate of the present invention.

FIG. 16 is a schematic vertical sectional view showing a method for manufacturing a microlens substrate of the present invention.

FIG. 17 is a schematic vertical sectional view showing a liquid crystal panel of the present invention.

FIG. 18 is a diagram schematically showing an optical system of the projection type display device of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Counter substrate for liquid crystal panels, 2 ... Substrate with concave portions for microlenses, 21 ... First substrate with concave portions for microlenses, 22 ... Substrate with concave portions for second microlenses, 3 ... Recesses, 31 ... First recesses, 32
... First recess, 33 ... Second recess, 34 ...
1st recessed part, 35 ... 2nd recessed part, 36 ... 1st recessed part, 37 ... 2nd recessed part, 4 ... Alignment mark, 41 ... Corner part, 42 ... 1st alignment mark, 43 ... 2nd alignment mark, 5 ...
-Glass substrate, 51 ... Transparent substrate, 52 ... Glass substrate, 53 ... First glass substrate, 54 ... Second glass substrate, 6 ... First mask layer, 61 ... ..First
, 611 to 614 ... Aperture, 62 ... Second aperture, 63 ... Second mask layer, 631 ... Third aperture, 64 ... Laminated mask, 641 ... First mask layer, 642 ... Second mask layer, 643 ... Third
Mask layers, 65 ... Concentric masks, 651, 65
2 ... 1st mask layer, 651 ', 652' ... gap, 653 ... 2nd mask layer, 69 ... back surface protection layer, 7 ... protection layer, 8 ... micro Lens, 9 ...
・ Spacer, 99 ・ ・ ・ Effective lens area, 100 ・ ・
・ Ineffective lens area, 11 ... Black matrix, 111 ... Opening, 12 ... Transparent conductive film, 13.
..Cover glass, 14 ... Resin layer, 141, 142
... Resin layer, 143, 144 ... Resin, 16 ...
Liquid crystal panel, 17 ... TFT substrate, 171 ... Glass substrate, 172 ... Pixel electrode, 173 ... Thin film transistor, 18 ... Liquid crystal layer, 70 ... Optical block, 71 ... Dichroic prism , 711, 71
2 ... Dichroic mirror surface, 713-715 ...
-Surface, 716 ... Emitting surface, 72 ... Projection lens, 7
3 ... Display unit, 74-76 ... Liquid crystal light valve, 300 ... Projection display device, 301 ... Light source, 302, 303 ... Integrator lens, 30
4, 306, 309 ... Mirror, 305, 307, 3
08 ... Dichroic mirror, 310-314 ...
・ Condensing lens, 320 ... Screen

Claims (22)

[Claims] 1. A mask having openings in a predetermined pattern is formed on a substrate, then wet etching is performed using the mask to form a large number of concave portions for microlenses on the substrate, and then the mask is formed. A method of manufacturing a substrate with a concave portion for a microlens to be removed, wherein an aspherical concave portion for a microlens is formed by performing wet etching in multiple steps while expanding the size of the opening of the mask. A method for manufacturing a substrate with concave portions for microlenses. 2. The method of manufacturing a substrate with concave portions for a microlens according to claim 1, wherein the mask is formed by laminating a plurality of mask layers having different opening sizes so that the openings are gradually increased. Method. 3. The method for manufacturing a substrate with concave portions for a microlens according to claim 2, wherein one of the openings of the mask layers adjacent to each other of the plurality of mask layers is included in the other. 4. The method of manufacturing a substrate with concave portions for microlenses according to claim 2, wherein the openings of the plurality of mask layers are arranged concentrically. 5. The method for manufacturing a substrate with concave portions for microlenses according to claim 1, wherein the mask is made of polycrystalline silicon. 6. The mask is formed on the substrate,
An annular first mask layer having a higher etching rate for an etching solution than the substrate, and an opening on the inner peripheral side of the first mask layer, and extending over the substrate and the first mask layer. The method of manufacturing a substrate with concave portions for microlenses according to claim 1, further comprising a formed second mask layer. 7. When the etching rate of the first mask layer with respect to the etching solution is a and the etching rate of the substrate with respect to the etching solution is b, the etching rate ratio a / b is 1.1 or more. The method for manufacturing a substrate with concave portions for microlenses according to claim 6. 8. The opening in the second mask layer is formed in the first mask layer.
The mask layer of claim 6 is arranged in the central portion of the mask layer.
The method for manufacturing a substrate with concave portions for a microlens according to. 9. The method for manufacturing a substrate with concave portions for microlenses according to claim 6, wherein a plurality of the first mask layers are provided. 10. The substrate with concave portions for microlens according to claim 9, wherein one of the first mask layers adjacent to each other of the plurality of first mask layers is included in the other and is separated from the other. Manufacturing method. 11. The method of manufacturing a substrate with concave portions for microlenses according to claim 9, wherein the plurality of first mask layers are concentrically arranged. 12. The method for manufacturing a substrate with concave portions for microlenses according to claim 1, wherein after the mask is removed, wet etching is further performed on the entire surface. 13. The method for manufacturing a substrate with concave portions for microlenses according to claim 1, wherein the substrate is a quartz glass substrate. 14. A substrate with concave portions for microlenses, which is manufactured by the method for manufacturing a substrate with concave portions for microlenses according to any one of claims 1 to 13. 15. A microlens substrate manufactured using the substrate with concave portions for microlenses according to claim 14, and having a plurality of microlenses. 16. The microlens substrate according to claim 15, wherein the microlens is a biconvex microlens. 17. The first microlens recessed substrate having a plurality of aspherical first microlens recesses according to claim 14, and the aspherical second microlens recessed substrate. The second microlens recessed substrate is bonded via a resin so that the first microlens recess and the second microlens recess face each other, whereby the first microlens is bonded. A microlens substrate comprising a biconvex microlens formed between the substrate with concave portions and the second substrate with concave portions for microlenses. 18. A counter substrate for a liquid crystal panel, comprising the microlens substrate according to claim 14. 19. A liquid crystal panel comprising the counter substrate for a liquid crystal panel according to claim 18. 20. A liquid crystal drive substrate having a pixel electrode, the liquid crystal panel counter substrate according to claim 18 bonded to the liquid crystal drive substrate, and a gap between the liquid crystal drive substrate and the liquid crystal panel counter substrate. A liquid crystal panel characterized by having a liquid crystal enclosed therein. 21. The liquid crystal panel according to claim 20, wherein the liquid crystal driving substrate is a TFT substrate. 22. A projection-type display device comprising the liquid crystal panel according to claim 18.