JPH08166502A - Microlens array and its production - Google Patents

Abstract

PURPOSE: To provide a microlens array which is suitable to increase the brightness of a liquid crystal image in a liquid crystal display device and has excellent heat resistance, light resistance, mechanical strength and chemical resistance, and to provide its production method. CONSTITUTION: Each lens which constitutes the microlens array 35 has a polygonal bottom shape and this polygon is such that lenses adjacent to each other can be arranged at small and the same intervals between lines of the bottoms of the adjacent lenses or in contact on the lines. The method of the microlens array 35 includes a process to form a lens resin pattern in which lens resin 34 having a polygonal bottom and a hemisphere on the bottom is arranged corresponding to the desired microlens array pattern and a process to etch and remove a part of the lens resin 34 and the glass substrates 21, 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microlens array in which minute microlenses are regularly arranged, and a liquid crystal display device, an optical integrated circuit, an optical coupler of an optical fiber array, a solid-state image pickup device, an electronic device. The present invention relates to a microlens array which is used in an optical system of a copying machine and is particularly suitable for a liquid crystal display device, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Generally, a backlight is used in a liquid crystal display device, but a pixel of the liquid crystal display element has a portion such as a black matrix or a driving element which does not pass through the backlight, and accordingly, it becomes darker. . In order to avoid this, an attempt has been made to improve the brightness of the liquid crystal image by using a microlens array and converging the amount of light emitted from the backlight to a portion of the pixel of the liquid crystal display element through which the backlight passes. .

For example, Japanese Laid-Open Patent Publication No. 5-40216 (hereinafter referred to as prior art 1) discloses an S / N of a solid-state image pickup device.
In order to improve the ratio, it is disclosed that the incident light on the light receiving unit is increased to increase the input signal strength. Specifically, an undercoat resin layer, a microlens forming resin layer, and a transfer photosensitive resin layer are provided in this order on the CCD, and then ultraviolet exposure and development are performed to form a transfer spherical lens pattern, Then, etching is performed by an oxygen plasma method to obtain a resin-made microlens on the undercoat resin layer.
By making the curved surface of the micro lens an aspherical surface, incident light to the transfer section and the wiring section (charge transfer section) adjacent to the light receiving section is also focused on the light receiving section, thereby increasing the amount of light received by the light receiving section. As a result, the light at the lens end is also focused on the lens center, and the S / N ratio is improved.

Japanese Patent Publication No. 61-46408 (hereinafter referred to as prior art 2) discloses a desired lens array on the surface of an optical glass substrate in order to shorten the manufacturing time of a microlens array having a large NA and a high density. After forming a resist pattern corresponding to the arrangement of, the optical glass substrate is subjected to reactive ion etching to form a columnar convex portion, and after removing the resist, an inert gas is further sealed in an electric furnace. It is disclosed that a microlens array in which circular convex lenses are arranged is obtained by heating to 1800 ° C. and thermally deforming a cylindrical convex portion into a spherical shape.

In Japanese Patent Laid-Open No. 4-123002 (hereinafter referred to as prior art 3), an ultraviolet curable resin is dropped on a lens array mold to form a liquid pool, and then a glass substrate is brought into close contact with it. Further, the molding die and the glass substrate are sandwiched by a pressure roll, and ultraviolet rays are irradiated from the glass substrate side to cure the resin. After that, it is disclosed that a mold release is performed to obtain a microlens array in which lenticular minute microlenses having a width of 100 μm and a length of 80 mm are regularly arranged on a glass substrate.

[0006]

FIG. 9 shows the microlens arrays disclosed in Prior Art 1 and Prior Art 2.
Microlens array 91 recognized in these prior arts
The shape of each of the microlenses 92 constituting the above is circular. Therefore, an empty corner portion 93 indicated by a mesh line in FIG. 9 exists between the lenses adjacent to each other of the circular microlenses 92. The empty corner portion 93 between the adjacent circular lenses reaches almost 10% of the total area of the surface of the microlens array even when the circular lenses are adjacent to each other and densely packed.
Therefore, when the microlens array including the circular lenses disclosed in Prior Art 1 and Prior Art 2 is used in a liquid crystal display device, the backlight light amount cannot be fully utilized and the brightness of the liquid crystal image is improved. I can't.

In particular, since a projection type liquid crystal display device uses high-luminance illumination as a light source, the microlens array used in this liquid crystal display device has high light resistance and high heat resistance to withstand the heat of the light source. Required. However, since the microlens arrays disclosed in Prior Art 1 and Prior Art 3 are made of resin, they have the drawback of low heat resistance, light resistance, mechanical strength, and chemical resistance.

On the other hand, in the microlens array disclosed in the prior art 2, the glass substrate is 1800 ° C.
Since the cylindrical convex portion is thermally deformed into a spherical shape by being exposed to the high temperature, the set numerical aperture (NA) cannot be obtained and a highly accurate microlens array cannot be obtained.

The present invention has been made to solve the above-mentioned drawbacks, and a first object of the present invention is to provide a microlens array suitable for increasing the brightness of a liquid crystal image of a liquid crystal display device. The second purpose is to provide a microlens array having excellent heat resistance, light resistance, mechanical strength, and chemical resistance, and the third purpose is to open the microlens array as designed. It is to provide a method for manufacturing a high-precision microlens array having a large number.

[0010]

The present invention has been made in order to solve these problems, and the microlens array of the present invention is a microlens array in which a plurality of convex lenses are regularly arranged. In each of the lenses forming the microlens array, the bottom surface has a polygonal shape and a convex spherical surface is formed above the bottom surface, and the bottom surface shape of the lens is on each side of the bottom surface of the lens. In this case, it is characterized in that the sides of the adjacent lenses are polygons that can be arranged at equal intervals or in contact with each other with a fine gap.

Further, in the method for manufacturing a microlens array of the present invention, a microlens array in which a lens-shaped resin having a polygonal bottom surface and a convex spherical surface formed above the glass substrate is desired. A step of forming a lens-like resin pattern arranged corresponding to the pattern,
A step of removing the lens-shaped resin and a part of the glass substrate by etching.

First, the microlens array of the present invention will be described. On each side of the bottom surface of the lens, a polygon in which the sides of adjacent lenses can be arranged at equal intervals or in contact with each other with a fine gap is, specifically, when all the lenses have the same shape, Examples include regular hexagons, squares, rectangles, parallelograms, trapezoids, regular triangles, and isosceles triangles. Such a polygon cannot condense light, which occurs when the sides of lenses whose adjacent bottom shapes are polygons are arranged or contact with each other with a minute gap and the bottom shape is a circle. The lenses can be arranged without forming empty corners. Such a state in which the individual lenses are packed and arranged in a close-packed state is hereinafter referred to as a close-packed state. The fine gap is preferably ⅕ or less of the length of the lens side.

The shape of the polygonal lens is preferably a regular triangle, a regular quadrangle or a regular hexagon. More preferably, it is a regular square or a regular hexagon. The reason is that the closest packed arrangement is possible, and a delta arrangement is possible in which the line connecting the centers of the adjacent lenses and the lenses located immediately below (or immediately above) both lenses forms a triangle, This is because when used in a liquid crystal display device, the liquid crystal image becomes clearer because the delta arrangement of liquid crystal pixels is likely to occur. Further, the microlens array is preferably made of glass.

Next, a method of manufacturing the microlens array of the present invention will be described. In the step of removing the lens-shaped resin and a part of the glass substrate by etching, the ratio of the etching rate of the glass substrate to the etching rate of the lens-shaped resin is 0.3 or more and 20 or less, preferably 0. It is characterized in that it is set to 3 or more and 7 or less. If the speed ratio is less than 0.3, the height of the obtained microlens becomes low, and if it exceeds 20, the desired microlens shape cannot be obtained, which is not preferable.

The reason for controlling the ratio of the etching rate of the glass substrate to the etching rate of the lens-shaped resin is as follows.
This is to match the shape of the microlens obtained by the etching process, that is, the curvature of the lens with the designed curvature. As means for controlling the etching rate ratio, selection of resin used for the lens-shaped resin pattern of the microlens array formed on the glass substrate, selection of gas used during etching, selection of glass for the glass substrate, etc. Done by

The resin is selected from polystyrene resins, acrylic resins, epoxy resins, urethane resins, polyolefin resins, polyimide resins, polyamide resins, polyester resins, and resins such as monomers and mixtures of these resins. In particular, when a resin having an aromatic ring is used, the etching rate of the resin in the resin pattern can be made slower than the etching rate of the glass substrate.

The gases are C ₂ F ₂ , CF ₄ , CHF ₃ ,
It is selected from a fluorine-based or chlorine-based simple gas represented by Cl ₂ or a mixed gas containing these gases. Further, these gases may contain oxygen.

The glass is selected from quartz glass, silicate glass, aluminosilicate glass and the like.

A lens in which a lens-shaped resin having a polygonal bottom surface and a convex spherical surface formed above the glass substrate is arranged corresponding to a desired microlens array pattern. As a method for forming the resin-like resin, a photoresist is applied on a glass substrate, a photomask having a desired microlens array pattern is brought into close contact, and after exposure to ultraviolet rays, development is performed to form a polygonal columnar resin. An array of columnar resin patterns is formed on the glass substrate. By heating and softening this columnar resin pattern or dry etching in oxygen plasma, a lens-shaped resin pattern in which lens-shaped resins are arranged can be obtained.

As another method for obtaining a lens-shaped resin pattern, an ultraviolet curing resin or a thermosetting resin is filled between a molding die having a molding surface corresponding to a desired microlens array pattern and a glass substrate, After curing or heat curing, the lens-shaped resin pattern is obtained by removing the molding die.

As a further method, after forming a pattern-arranged polygonal columnar resin layer on a glass substrate using a molding die, the resin layer is heated to soften the surface to form a molding surface. It is also possible to obtain a lenticular resin pattern without using a lens array molding die that has been subjected to curved surface processing corresponding to the lens shape. Further, it is also possible to form the lens-shaped resin pattern by the intaglio printing method.

[0022]

In the microlens array of the present invention, the shape of the microlenses that are formed is such that the bottom surface has a polygonal shape and is formed in the shape of a convex spherical surface above it, and at each side of the bottom surface of the lens, By making the adjacent lenses into polygons that can be arranged at equal intervals or in contact with each other with a minute gap, it becomes possible to arrange the individual microlenses in a close-packed form, and it is possible to arrange adjacent microlenses as in the case of conventional circular lenses. It is possible to extremely reduce the empty corners existing between the matching lenses, that is, the empty corners where the irradiation light is not focused by the lenses. In particular, when the microlens array of the present invention is used in a liquid crystal display device, the amount of light incident on the pixels of the liquid crystal display element increases.

According to the method of manufacturing a microlens array of the present invention, the lens-shaped resin provided on the glass substrate is
Since a part of the glass substrate is removed by etching, a glass microlens array having the same pattern as the lens-shaped resin pattern and having excellent heat resistance, light resistance, mechanical strength, and chemical resistance can be obtained.

Furthermore, the method of manufacturing a microlens array of the present invention employs an etching method, unlike the prior art 2 in which a cylindrical convex portion provided on a glass substrate is thermally softened into a spherical shape at high temperature, and When the lens-shaped resin provided on the glass substrate and a part of the glass substrate are removed by etching, by controlling the etching rate ratio between the lens-shaped resin and the glass substrate, a micro-pore having a numerical aperture as designed is obtained. A lens array is obtained.

[0025]

Embodiments of the present invention will now be described in detail with reference to the drawings. [Embodiment 1] FIG. 1 shows the present embodiment in which individual microlenses 2 each having a regular hexagonal shape on the bottom surface (the length of one side is 50 μm) and formed in a convex spherical shape above the hexagonal shape are arranged in a close-packed form. It is a figure which shows the micro lens array 1 of an example. FIG.
1A is a plan view of the microlens array, and FIG. 1B is a cross-sectional view taken along line I-I of FIG. 1A. The method of manufacturing the microlens array of this embodiment will be described below with reference to FIGS.
4 will be described in detail.

After forming a chromium layer 22 having a film thickness of 800 Å on the quartz glass substrate 21 by using a sputtering device, a negative type electron beam resist is further applied to form a resist layer 23.
To obtain a photomask blank 24 (see FIG. 2).
(A)). Next, an electron beam irradiating device is used to irradiate a portion corresponding to the microlens with an electron beam in the direction of the arrow in accordance with a desired pattern of the microlens array in which regular hexagonal microlenses are arranged (see FIG. 2).
(B)), using a developing solution (Tosoh CMS solution),
The resist in the portion not irradiated with the electron beam, that is, the resist in the portion corresponding to the gap between the lenses is dissolved and removed (FIG. 2 (c)), and the chromium layer portion exposed by the resist removal is removed by a chromium etching liquid (manufactured by Kanto Chemical Co., Inc. HY solution) for 90 seconds to remove (FIG. 2D), and then for 30 minutes in concentrated sulfuric acid at 120 ° C. for 30 minutes to remove the resist layer 2 on the chromium layer 22.
By removing 3 by dissolution, a photomask 25 was obtained in which the chromium layer 22 portion (the portion corresponding to a regular hexagonal microlens having a side of 50 μm) was arranged in a close-packed state at intervals of 2 μm (FIG. 2 (e)).

Then, 0.8 .mu.m was spin-coated on the quartz glass substrate 31 having a square surface of 3 inches square.
A positive type photoresist (AZ-1350 manufactured by Hoechst Co., Ltd.) having a film thickness of m was applied to form the resin layer 32. On the resin layer 32, the photomask 2 previously created
The surface of the chrome layer 22 of No. 5 was brought into close contact with the surface of the chrome layer 22 and exposed to ultraviolet rays from the direction of the arrow at a dose of 200 mJ / cm ² using an ultraviolet exposure device (FIG. 3 (a)), and then a developing solution (AZ from Hoechst Co.) was used. By dipping it in a developer solution) for 60 seconds and developing, the resist in the portion irradiated with ultraviolet rays (the portion corresponding to the gap between the individual microlenses) is dissolved and removed,
The columnar resin 33 was obtained on the quartz glass substrate 31 (FIG. 3).
(B)). The quartz glass substrate 31 provided with the columnar resin 33 is heated in an oven at 200 ° C. for 30 minutes to heat and soften the surface of the columnar resin 33, and the bottom shape is a regular hexagon (length of one side is 50 μm). A lens-like resin 3 having a convex spherical surface shape and having a height of 0.78 μm.
The lens-shaped resin pattern A shown in FIG. 4 in which 4 were arranged was obtained on the quartz glass substrate 31 (FIG. 3 (c)).

Further, using a parallel plate type reactive ion etching apparatus, a high frequency power of 300 W is supplied,
The CHF ₃ flow rate of 150 sccm was applied to the quartz glass substrate 31 provided with the lens resin 34 at a resin etching rate of 0.008 μm / min and a quartz glass etching rate of 0.08 μm / min. Dry etching was performed until 34 portions disappeared, and a microlens array 35 made of quartz glass having the same pattern as the lens-shaped resin pattern A was obtained (FIG. 3D). At this time, since the etching rate ratio of the quartz glass to the etching rate of the resin is 10.0, the quartz glass has 10% of the resin.
The height of the microlens 36 is 10.times.10 μm, which is 10 times the height of the original lenticular resin 34.
It is amplified to m. Obtained microlens array 3
5 is a numerical aperture (N) having a shape in which the bottom surface is a regular hexagon with a side length of 50 μm and is formed in a convex spherical shape above it.
A) The 0.35 microlenses 36 are arranged in a close-packed manner at intervals of 2 μm.

[Embodiment 2] This embodiment will be described with reference to FIGS. First, in the same manner as in Example 1, a photomask 5 having a pattern B (see FIG. 6) in which regular squares having a side of 20 μm are arranged in a close-packed shape at intervals of 1 μm.
5 was created. However, in Example 1, the quartz glass substrate 21
The portion of the chromium layer 22 provided above is the portion corresponding to the microlens, but in the present embodiment, the chromium layer 54 is used.
The portion was set as a portion corresponding to a gap between individual microlenses. Next, a negative type photoresist (Tokyo Ohka Kogyo Co., Ltd., OMR-85) having a film thickness of 1.0 μm is applied on a quartz glass substrate 51 having a surface of 3 inches square by a spin coat method. To form the resin layer 52. The surface of the photomask 55 previously formed on which the chrome layer 54 is provided is brought into close contact with the resin layer 52 provided on the quartz glass substrate 51, and an irradiation amount of 20 is applied using an ultraviolet exposure device.
After UV exposure at 0 mJ / cm ² from the direction of the arrow (Fig. 5
(A)), by immersing in a developing solution (AZ developer solution manufactured by Hoechst) for 60 seconds and developing, the resist in the portion not irradiated with electron beam (the portion corresponding to the gap between individual microlenses) is dissolved After the removal, the columnar resin 56 was obtained on the quartz glass substrate 51 (FIG. 5B). By dry-etching the quartz glass substrate 51 provided with the columnar resin 56 in oxygen plasma, the columnar resin 56 is gradually scraped from the upper peripheral portion, and the shape of the bottom surface is a quadrangle (the length of one side is 20 μm) and the upper side thereof. A lens-shaped resin 57 having a convex spherical surface shape and a height of 0.88 μm
The lens-shaped resin pattern B shown in FIG. 6 in which the elements were arranged was obtained on the quartz glass substrate 51 (FIG. 5C).

Next, using a parallel plate type reactive ion etching apparatus, a high frequency power of 300 W was supplied and C
₂ F ₆ flow rate 20 sccm, CHF ₃ flow rate 100 sccm
Under the conditions, the quartz glass substrate 51 on which the lens-shaped resin pattern B is provided has a resin etching rate of 0.01.
3 μm / min, quartz glass etching rate is 0.065
Dry etching was performed at a rate of μm / min until the lens-shaped resin portion disappeared to obtain a microlens array 58 made of quartz glass having the same pattern as the lens-shaped resin pattern B (FIG. 5D). Since the etching rate ratio of the quartz glass to the etching rate of the resin at this time is 5.0, the quartz glass is etched 5 times faster than the resin,
The height of the microlens 59 is amplified to 4.35 μm, which is five times the height of the original lens-shaped resin. The obtained microlens array 58 has a shape in which the bottom surface is a regular quadrangle with a side length of 20 μm and is formed in a convex spherical shape above it, and the microlenses 59 having a numerical aperture (NA) of 0.45 are spaced at intervals of 1 μm. Are arranged in a close-packed form.

[Embodiment 3] This embodiment will be described with reference to FIGS. First, set a predetermined program on the NC machine tool, and form a 3 mm thick nickel plate polished on the mirror surface into an array of concave parts with a regular triangle of 60 μm on each side and a depth of 3 μm in a close-packed manner. A concave microlens array molding die 72 having a pattern C (see FIG. 8) in which the concave portions are arranged in contact with each other in the closest packed state is obtained. This mold 7
Resin mixture 7 of 0.9 mol of cyclohexyl methacrylate and 0.1 mol of hydroxyethyl methacrylate containing 4% by weight of lauryl peroxide on the surface of the concave portion 2
3 was applied. Apply 3 to the surface coated with this resin mixture 73.
After sticking the inch square non-alkali glass substrate (NH Techno Glass Co., NA45) 71 so that air bubbles do not enter,
As shown by the arrow, ultraviolet rays were radiated from the side opposite to the surface of the mold 72 on which the recess was processed (FIG. 7A). afterwards,
After heat-curing at 160 ° C. for 20 minutes, the microlens array molding die 72 is removed to remove the alkali-free glass substrate 7
A lens-shaped resin pattern C in which a lens-shaped resin 74 having a numerical aperture (NA) of 0.17 and a height of 3 μm was arranged on the surface of No. 1 was obtained (FIG. 7B).

Next, using a diffusion magnetic field type dry etching apparatus, microwave power 75 W, coil current 15 A, Cl ₂
Under the condition of a flow rate of 30 sccm, the non-alkali glass substrate 71 provided with the lens-shaped resin pattern C has a resin etching rate of 0.095 μm / min and an alkali-free glass etching rate of 0.050 μm / min. Dry etching was performed until the lens-shaped resin 74 portion disappeared to obtain a microlens array 75 made of non-alkali glass having the same pattern as the lens-shaped resin pattern C (FIG. 7).
(C)). Since the etching rate ratio of the alkali-free glass to the etching rate of the resin at this time is 0.53, the alkali-free glass is etched at a rate 0.53 times that of the resin, and the height of the microlens 76 is the same as the original. The height is reduced to 1.5 μm, which is 0.53 times the height of the lenticular resin 74. The obtained microlens array 75 has a bottom surface of a triangular shape having a side length of 60 μm and a convex spherical surface formed above the microlens array 75, and the microlenses 76 having a numerical aperture (NA) of 0.08 are closely packed. Are arranged in.

As a dry etching apparatus, a magnetron ion etching apparatus or the like may be used in addition to the parallel plate type reactive ion etching apparatus and the diffusion magnetic field type dry etching apparatus shown in the embodiments.

In Examples 1 and 2, the photolithography method was used for forming the columnar resin pattern on the glass substrate. This method was used for forming the photomask pattern and individual lens shapes. This is because the accuracy is high and the degree of freedom in selecting the lens shape is large, which is more preferable.

Furthermore, if the bottom surface of the lenses forming the microlens array of the present invention is a polygonal shape in which the individual microlenses can be arranged in the closest packing state,
The shape is not limited to a regular polygon, and may be a parallelogram or an isosceles triangle. Further, polygons having different shapes may be combined and arranged.

[0036]

According to the present invention, the bottom shape of the microlens is a polygon that can be arranged in a close-packed manner, so that an empty corner where the irradiation light is not focused by the lens is eliminated between the adjacent lenses. be able to. In particular, when the microlens array of the present invention is used in a liquid crystal display device,
Incident light can be efficiently taken into the pixels of the liquid crystal display element, and the brightness of the liquid crystal image can be significantly improved. further,
The effect is further enhanced by forming each of the lenses forming the microlens array of the present invention into a polygonal shape that matches the shape of the pixel of the liquid crystal display element. The microlens array manufactured by the manufacturing method described above is made of glass and has excellent heat resistance, light resistance, and chemical resistance. Further, when the lens-shaped resin pattern is etched, by controlling the etching rate of the glass substrate with respect to the etching rate of the resin, it is possible to provide a method for manufacturing a highly accurate microlens array having a numerical aperture as designed.

[0037]

[Brief description of drawings]

FIG. 1 is a diagram showing a plan view (a) and a sectional view (b) of a microlens array according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a key portion showing the method of manufacturing the photomask used in Embodiment 1 of the present invention.

FIG. 3 is a sectional view of a key portion showing the method of manufacturing the microlens array according to the first embodiment of the present invention.

FIG. 4 is a plan view showing a part of the lens-shaped resin pattern according to the first embodiment of the present invention.

FIG. 5 is a sectional view of a key portion showing the method of manufacturing the microlens array according to the second embodiment of the present invention.

FIG. 6 is a plan view showing a part of a lens-shaped resin pattern according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view of essential parts showing a method for manufacturing a microlens array according to a third embodiment of the present invention.

FIG. 8 is a plan view showing a part of a lens-shaped resin pattern according to a third embodiment of the present invention.

FIG. 9 is a plan view showing a part of a conventional microlens array.

[0038]

[Explanation of symbols]

 1 Microlens Array 2 Microlens 21 Quartz Glass Substrate 22 Chrome Layer 23 Resist Layer 24 Photomask Blanks 25 Photomask 31 Quartz Glass Substrate 32 Resin Layer 33 Columnar Resin 34 Lens Resin 35 Microlens Array 36 Microlens 51 Quartz Glass Substrate 52 Resin layer 53 Quartz glass substrate 54 Chrome layer 55 Photomask 56 Columnar resin 57 Lens resin 58 Microlens array 59 Microlens 71 Alkali-free glass substrate 72 Mold 73 Resin mixture 74 Lens resin 75 Microlens array 76 Microlens 91 Micro Lens array 92 Circular microlens 93 Empty corner A resin pattern B resin pattern C resin pattern

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hiroyuki Kosuge 2-7-5 Nakaochiai, Shinjuku-ku, Tokyo Hoya Co., Ltd.

Claims (4)

[Claims] 1. In a microlens array in which a plurality of convex lenses are regularly arranged, each lens forming the microlens array has a polygonal bottom surface and a convex spherical surface formed above the polygonal lens. And a bottom surface of the lens is a polygon in which each side of the bottom surface of the lens is a polygon in which adjacent lens sides can be arranged at equal intervals or in contact with each other with a fine gap. And a microlens array. 2. The microlens array according to claim 1, wherein the microlens array is made of glass. 3. A lens in which a lens-shaped resin having a polygonal bottom surface and a convex spherical shape formed above the glass substrate is arranged corresponding to a desired microlens array pattern. A step of forming a resin pattern
The method of manufacturing a microlens array according to claim 2, further comprising a step of removing the lens-shaped resin and a part of the glass substrate by etching. 4. In the step of removing the lens-shaped resin and a part of the glass substrate by etching, the ratio of the etching rate of the glass substrate to the etching rate of the lens-shaped resin is 0.3 or more and 20 or less. The method for manufacturing a microlens array according to claim 3, wherein