JP2002328203A - Lens array manufactured by press forming - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide techniques to form a lens array with high accuracy. SOLUTION: The lens array 140 is manufactured by press forming a fused optical material. The lens array 140 has an almost plate-like base 142 and a plurality of small lenses 146 formed on one surface B1 of the base 142. Only a plurality of outermost small lenses 146o formed in the outermost periphery have side faces not in adjacent to other small lenses. The side faces of the outermost peripheral small lenses 146o have inclined faces directing to the outer edge of the base 142 and obliquely crossing with the one face B1 of the base 142.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illumination optical system used for a projector, and more particularly to a lens array manufactured by press-molding a molten optical material.

[0002]

2. Description of the Related Art In a projector, light emitted from an illumination optical system is modulated according to image information (image signal) by a liquid crystal light valve or the like, and an image is displayed by projecting the modulated light on a screen. Is done.

An illumination optical system usually includes a light source device, first and second lens arrays, and a superimposing lens. The light beam emitted from the light source device is split into a plurality of partial light beams by a plurality of small lenses provided in the first lens array. After passing through the second lens array including the plurality of small lenses corresponding to the plurality of small lenses of the first lens array, the plurality of partial light beams are superimposed on the liquid crystal light valve by the superimposing lens. By using such an illumination optical system, the intensity distribution of light illuminating the liquid crystal light valve can be made substantially uniform.

[0004] The lens array usually includes a base portion and a plurality of small lenses arranged in a matrix on the base portion. The outermost outermost small lenses arranged at the outermost periphery have side surfaces (sidewalls) perpendicular to the surface of the base portion on the side not adjacent to other small lenses.

[0005]

By the way, the above-mentioned lens array can be manufactured by press-forming molten glass using a manufacturing apparatus having a mold. However, when this method is used, there is a problem that it is relatively difficult to accurately mold the lens array. This is because the boundary region between the lens surface of the outermost peripheral small lens and the above-described side wall of the outermost peripheral small lens is not formed into the same shape as the molding surface of the molding die, and is rounded. .

If the lens array is not formed with high precision, the illumination optical system and the projector may not be used.
It becomes difficult to efficiently guide the light incident on the lens array to the subsequent optical components such as the second lens array, and the light use efficiency in the illumination optical system and the projector is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and has as its object to provide a technique capable of forming a lens array with high accuracy.

[0008]

In order to solve at least part of the above-mentioned problems, a first apparatus of the present invention is a lens array manufactured by press-forming a molten optical material. There is a substantially plate-shaped base portion and a plurality of small lenses formed on one surface of the base portion, and only a plurality of outermost small lenses formed on the outermost periphery are different from other small lenses. Having sides on non-adjacent sides,
The plurality of small lenses, wherein the side surface of at least one of the outermost peripheral small lenses faces an outer edge of the base portion and includes a slope obliquely intersecting the one surface of the base portion. Features.

In this lens array, only a plurality of outermost small lenses formed on the outermost periphery have side surfaces on a side not adjacent to other small lenses, and the side surface of at least one outermost small lens is It includes a slope facing the outer edge of the base portion and obliquely intersecting one surface of the base portion. By adopting such a shape, the lens array can be formed in the same shape as the molding surface of the mold, so that the lens array can be accurately molded.

In the above device, the slope may be a flat surface.

In the above apparatus, the slope may be:
The curved surface may have a curvature different from the curvature of the lens surface of the outermost lens.

In the above apparatus, the slope may be:
It may include a flat surface and a connecting surface for smoothly connecting the flat surface and the lens surface of the outermost peripheral small lens.

As described above, various shapes can be adopted as the slope included in the side surface of the outermost peripheral small lens. And
When the side surface of the outermost peripheral small lens includes the above-described inclined surface, the lens array can be easily formed into the same shape as the molding surface of the mold.

In the above apparatus, at least one lens surface may be formed on the other surface of the base.

This makes it possible to change the emission direction of the light emitted from each small lens.

In the above apparatus, the plurality of small lenses are formed in a matrix, and two side surfaces of each of the outermost small lenses formed at four corners of the plurality of outermost small lenses are: It is preferable to include molding surfaces that are substantially perpendicular to each other and that are substantially perpendicular to the one surface of the base portion.

With this arrangement, the relatively smooth molding surface included in the side surfaces of the outermost small lenses at the four corners can be used as the reference surface of the lens array, so that the lens array can be easily positioned.

In the above apparatus, the base portion has a substantially rectangular outer shape, and two side surfaces at four corners of the base portion are substantially orthogonal to each other, and are formed on the one surface of the base portion. It is preferable to include a molding surface that is substantially orthogonal to the surface.

With this configuration, the relatively smooth molding surface included in the four corners of the base portion can be used as the reference surface of the lens array, so that the lens array can be easily positioned.

According to a second aspect of the present invention, there is provided an illumination optical system, comprising: a light source device; a lens array for dividing a light beam emitted from the light source device into a plurality of partial light beams; And a superimposing optical system for superimposing the partial light beam on a predetermined illumination area, wherein the lens array is any one of the lens arrays described above.

In this illumination optical system, since the above-described lens array formed with high precision is used, the efficiency of use of light in the illumination optical system can be improved.

According to a third aspect of the present invention, there is provided a projector for projecting and displaying an image, comprising: an illumination optical system; an electro-optical device for modulating light from the illumination optical system in accordance with image information; A projection optical system for projecting modulated light obtained by the device, the illumination optical system includes a light source device, and a lens array for dividing a light beam emitted from the light source device into a plurality of partial light beams. A superimposing optical system for superimposing the plurality of partial light beams on the electro-optical device,
Wherein the lens array is the lens array according to any of the above.

In this projector, since the above-described lens array formed with high precision is used, the light use efficiency of the projector can be improved.

A fourth apparatus of the present invention is a manufacturing apparatus for manufacturing a lens array by press-molding a molten optical material, wherein the first apparatus includes a lens surface of a plurality of small lenses of the lens array. A first molding die for molding a surface, a second molding die for molding a second surface of the lens array, and a position of at least one of the first and second molding dies. Controlling the position of the first mold and the second mold by adjusting a distance between the first mold and the second mold, wherein the lens array has a substantially plate-shaped base, The plurality of small lenses formed on one surface of the plurality of small lenses, wherein only the plurality of outermost small lenses formed on the outermost periphery have side surfaces on a side not adjacent to other small lenses. And at least one outermost periphery The side surface of the lens faces an outer edge of the base portion and includes a slope obliquely intersecting with the one surface of the base portion, and the first mold is capable of molding the outer shapes of the plurality of small lenses. It has a characteristic molding surface.

This manufacturing apparatus is provided with two molds, and the first mold has a molding surface capable of molding the outer shape of a plurality of small lenses of the lens array. By using such a molding die, the lens array can be molded in the same shape as the molding surface of the molding die, so that the lens array can be molded with high precision.

In the above apparatus, the second mold may include a central molding part for molding a central portion of the second surface of the lens array, and a second molding part for molding the second part of the lens array.
A peripheral molding portion for molding a peripheral portion of the surface of the first molding die, wherein the central molding portion has substantially the same size as an area for molding the lens surfaces of the plurality of small lenses of the first molding die. Having a molding surface, the position control unit sets the distance between the first molding die and the second molding die to a predetermined size, and then further sets the first molding die and the Second
It is preferable to reduce the distance between the mold and the central molding portion.

With this arrangement, the molten optical material is easily spread along the molding surface of the first mold, so that the lens surfaces of the plurality of small lenses of the lens array can be molded with higher accuracy.

In the above apparatus, the first and the second
The optical material block molded by the molding die includes the lens array having the substantially rectangular base portion and a surplus portion around the lens array, and the first and second molding dies are
It is preferable that both surfaces of the optical material block have molding surfaces having a substantially frame-shaped groove at a boundary between the lens array and the surplus portion.

In this case, by bending the optical material block along the substantially frame-shaped groove, the surplus portion can be easily cut off to obtain a lens array.

In the above apparatus, the first and the second
It is preferable that at least one of the molding dies has a molding surface such that the thickness of the surplus portion of the optical material block is smaller than the thickness of the base portion.

In this way, even when the thickness of the base portion is relatively large, the surplus portion can be relatively easily cut off.

In the above apparatus, at least one of the first and second molding dies may be configured such that when the surplus portion of the optical material block is cut along the substantially frame-shaped groove, It is preferable that side surfaces at four corners of the base portion have molding surfaces that are substantially perpendicular to each other and include a molding surface that is substantially perpendicular to the one surface of the base portion.

In this way, the molding surfaces included in the side surfaces at the four corners of the base portion can be used as the reference surfaces of the lens array, so that the manufactured lens array can be easily positioned.

In the above-mentioned apparatus, the first and the second
The mold has a molding surface such that the position of the groove formed on one surface of the optical material block substantially matches the position of the groove formed on the other surface of the optical material block. Is also good.

In the above apparatus, the first and second molds may be such that the position of the groove formed on one surface of the optical material block is at least at four corners of the base portion. May have a molding surface that is shifted to the outside of the position of the groove formed on the other surface.

With this arrangement, the molding surface included in the side surface at the four corners of the base portion can be used as the reference surface of the lens array, and the cut surface formed when the surplus portion is cut off is smaller than the molding surface. Can be prevented from protruding outward, so that the manufactured lens array can be positioned more easily.

[0037] In the above apparatus, the first molding die may separate the molded optical material block from the first molding die from the molding surface of the first molding die. At least one protruding towards the molding surface of the mold
It is preferable to provide two release parts.

When the optical material block is molded, the optical material block may adhere to the molding surface of the first mold. However, as described above, if the first mold has the release part, the molded optical material block can be easily separated from the first mold.

[0039]

DETAILED DESCRIPTION OF THE INVENTION First Embodiment: Next, an embodiment of the present invention will be described based on an embodiment. FIG. 1 is a schematic configuration diagram showing an example of a projector to which the present invention has been applied. The projector 1000 includes an illumination optical system 100, a color light separation optical system 200, a relay optical system 220, three liquid crystal light valves 300R, 300G, 300B, a cross dichroic prism 320, and a projection optical system 34.
0.

The light emitted from the illumination optical system 100 is separated into three color lights of red (R), green (G), and blue (B) in the color light separation optical system 200. The separated color lights are modulated in the liquid crystal light valves 300R, 300G, and 300B according to image information. The liquid crystal light valves 300R, 300G, and 300B of this embodiment include a liquid crystal panel corresponding to the electro-optical device according to the present invention, and polarizing plates disposed on the light incident surface side and the light exit surface side. Liquid crystal light valves 300R, 300G, 300B
Are modulated by the cross dichroic prism 320 and projected on the screen SC by the projection optical system 340. Thus, an image is displayed on the screen SC. The configuration and function of each unit of the projector as shown in FIG. 1 are described in detail in, for example, Japanese Patent Application Laid-Open No. 10-325954 disclosed by the present applicant. Omitted.

FIG. 2 is an explanatory diagram showing the illumination optical system 100 of FIG. 1 in an enlarged manner. The illumination optical system 100 includes the light source device 1
20 and first and second lens arrays 140 and 150
, A polarization generating optical system 160 and a superimposing lens 170. Each optical component is arranged with reference to the system optical axis 100ax. Here, the system optical axis 100
ax is the central axis of the light beam emitted from the light source device 120. In FIG. 2, the illumination area LA illuminated by the illumination optical system 100 corresponds to the liquid crystal light valve 300 of FIG.
R, 300G, and 300B.

The light source device 120 includes a lamp 122, a reflector 124 having a spheroidal concave surface, and a parallelizing lens 126. The lamp 122 is arranged near the first focal point on the spheroid of the reflector 124. The light emitted from the lamp 122 is reflected by the reflector 12
4 and the reflected light travels while being collected toward the second focal point of the reflector 124. Parallelizing lens 12
6 converts the incident condensed light into light substantially parallel to the system optical axis 100ax.

As the light source device 120, a reflector having a concave surface in the shape of a paraboloid of revolution may be used. In this case, the light reflected by the reflector is the system optical axis 1
Since it is almost parallel to 00ax, the collimating lens 126 can be omitted.

First and second lens arrays 140, 1
50 has a plurality of small lenses 146 and 156, respectively. The first lens array 140 includes the light source device 120
Has a function of dividing a substantially parallel light beam emitted from the light beam into a plurality of partial light beams and emitting the light beam. Then, the second lens array 150 sets the central axis of each of the partial light beams emitted from the first lens array 140 to the system optical axis 1.
It has a function to make it almost parallel to 00ax. Also,
The second lens array 150 has a function of forming an image of each small lens 146 of the first lens array 140 on the illumination area LA together with the superimposing lens 170.

Each of the small lenses 146 and 156 is a plano-convex eccentric lens, and the outer shape when viewed from the x direction is set to be substantially similar to the illumination area LA (liquid crystal light valve). . However, as shown in FIG. 2, the first small lens 146 and the second small lens 156 use decentered lenses having different decentering methods. For example, the outermost small lens 146 of the first lens array 140 is
The principal ray of the divided partial light beam is the system optical axis 100a.
It is eccentric so as to advance diagonally to x. The outermost small lens 156 of the second lens array 150 is
The principal ray of the partial light beam obliquely incident on the system optical axis 100ax is decentered so as to be substantially parallel to the system optical axis 100ax.

Each small lens 1 of the first lens array 140
The partial light beam emitted from 46 is, as shown in FIG.
The light is condensed through the small lenses 156 of the second lens array 150 in the vicinity thereof, that is, in the polarization generating optical system 160.

The polarization generating optical system 160 is composed of an integrated 2
And two polarization generating element arrays 160A and 160B. First and second polarization generating element arrays 160A, 1
60B is arranged symmetrically with respect to the system optical axis 100ax.

FIG. 3 is an explanatory diagram showing, on an enlarged scale, the first polarization generating element array 160A of FIG. FIG. 3 (A)
FIG. 3B is a perspective view of the first polarization generating element array 160A, and FIG. 3B is a plan view when viewed from the + z direction. The polarization generating element array 160A is
2, a polarizing beam splitter array 164, and a plurality of λ / 2 phase difference plates 166 selectively disposed on the light exit surface of the polarizing beam splitter array 164. The same applies to the second polarization generating element array 160B.

As shown in FIGS. 3A and 3B, the polarizing beam splitter array 164 is formed by laminating a plurality of columnar glass members 164c having a substantially parallelogram cross-sectional shape. Polarized light separating films 164a and reflecting films 164b are alternately formed on the interface between the glass materials 164c. Note that a dielectric multilayer film is used as the polarization separation film 164a, and a dielectric multilayer film or a metal film is used as the reflection film 164b.

The light-shielding plate 162 has an opening surface 162a and a light-shielding surface 162b arranged in a stripe pattern. The opening surface 162a and the light shielding surface 162b are provided corresponding to the polarization separation film 164a and the reflection film 164b, respectively. As a result, the partial light beam emitted from the first lens array 140 (FIG. 2) passes through the aperture surface 162a to the polarization splitting film 1 of the polarization beam splitter array 164.
The light is incident only on 64a and not on the reflective film 164b.

The principal ray (center axis) of each partial ray bundle emitted from the first lens array 140 (FIG. 2) is shown in FIG.
As shown by the solid line in (B), the light enters the opening surface 162a of the light shielding plate 162 almost in parallel with the system optical axis 100ax.
The partial light beam that has passed through the aperture surface 162a is
At 64a, the s-polarized partial light beam and the p-polarized partial light beam are separated. The p-polarized partial light beam passes through the polarization splitting film 164a, and enters the polarization beam splitter array 1
Emitted from 64. On the other hand, the s-polarized partial light beam is reflected by the polarization splitting film 164a and further reflected by the reflection film 164b, and then is reflected by the polarization beam splitter array 16a.
Injected from 4.

The λ / 2 retardation plate 166 is a part of the light exit surface of the polarization beam splitter array 164,
It is formed only on the light exit surface of the p-polarized partial light beam transmitted through 4a. The λ / 2 retardation plate 166 has a function of converting incident linearly polarized light into linearly polarized light whose polarization direction is orthogonal. Therefore, the p-polarized partial ray bundle is
The λ / 2 phase difference plate 166 converts the s-polarized light beam into a partial light beam and emits it. Thereby, the partial light beam (s + p) without polarization incident on the polarization generating element array 160A.
Is converted into an s-polarized light beam and emitted. Note that λ / λ is applied only to the light exit surface of the s-polarized partial beam.
By arranging the two phase difference plates 166, the partial light beam incident on the polarization generating element array 160A can be converted into a p-polarized partial light beam and emitted.

The plurality of partial light beams emitted from the first lens array 140 are coupled to the polarization generating optical system 1 as described above.
At 60, each partial light beam is separated into two partial light beams, and is converted into almost one type of linearly polarized light having a uniform polarization direction. The plurality of partial light beams having the same polarization direction are superimposed on the illumination area LA by the superimposing lens 170 shown in FIG. At this time, the intensity distribution of the light illuminating the illumination area LA is substantially uniform.

As described above, the illumination optical system 100 (FIG. 1)
Emits illumination light (s-polarized light) having a uniform polarization direction, and illuminates the liquid crystal light valves 300R, 300G, and 300B via the color light separation optical system 200 and the relay optical system 220.

FIG. 4 shows the first lens array 140 of FIG.
It is explanatory drawing which expands and shows. FIG. 4A is a plan view when the first lens array 140 (FIG. 2) is viewed from the −x direction. FIG. 4B is a sectional view taken along line BB of FIG.
FIG. 4C is a schematic cross-sectional view taken along a plane CC in FIG. 4A.

As shown, the first lens array 14
0 is a substantially plate-shaped base portion 14 having a substantially rectangular outer shape.
2 and a plurality of small lenses 146 formed on one surface B1 of the two surfaces B1 and B2 of the base portion 142. Note that the plurality of small lenses 146 are
2 are formed in a matrix in a region inside the outer edge.

As described above, each small lens 146 is a plano-convex eccentric lens having a substantially rectangular outer shape, and is symmetric with respect to the y-axis and the z-axis orthogonal to the system optical axis 100ax. Are arranged. Each small lens 146
The sizes of the lens surfaces in the y and z directions are set substantially equal to each other. The thickness of the small lenses arranged along the y direction is set so as to gradually increase from the center of the first lens array 140 toward the outer periphery. Here, the "thickness" of the small lens is
It means the maximum distance between the light incident surface and the light exit surface of the small lens 146 on the base portion 142.

As shown in FIG. 4, each small lens 146
The lens surfaces of two adjacent small lenses 146 are connected so as to be continuous. At this time, only the outermost peripheral small lenses 146o formed on the outermost periphery have side surfaces on the side not adjacent to other small lenses. That is, of the 48 small lenses 146, the 24 inner circumferential small lenses 146i formed on the inner circumferential side have no side surfaces because they are adjacent to other small lenses around the periphery. . On the other hand, the 24 outermost peripheral small lenses 146o formed on the outermost periphery are:
It has a side surface that is not adjacent to other small lenses around it. Specifically, the outermost peripheral small lenses 146o formed at the four corners have two side surfaces, and the other outermost peripheral small lenses 146o have one side surface. In addition, a flat inclined surface extending toward the outer edge of the base portion 142 is formed on the side surface of the outermost peripheral small lens 146o. In other words, on the side surface of the outermost peripheral small lens 146o, the first surface B of the base portion 142 faces the outer edge of the base portion 142.
A flat inclined surface which crosses obliquely with respect to 1 is formed.

The lens array 140 of this embodiment is
It is produced by press-molding molten glass, and both surfaces L1 and L2 of the lens array 140 are molding surfaces molded by a molding die.

FIG. 5 is an explanatory diagram showing a procedure for manufacturing the lens array 140 of FIG. FIG. 5 shows a state when the manufacturing procedure of the lens array 140 is observed in the same cross section as FIG. 4C. As illustrated, the lens array 140 is manufactured by the manufacturing apparatus 600 press-forming the molten glass G. Manufacturing equipment 600
Has two molds 610 and 620 and a position control unit 630. The first molding die 610 has an irregular molding surface S1 for molding the first surface L1 including the lens surfaces of the plurality of small lenses 146 of the lens array 140 shown in FIG. The second mold 620 includes the lens array 14.
Plane molding surface S2 for molding the second surface L2
have. The two molds 610 and 620 are
Although it has a substantially rectangular outer shape, the second molding die 620
Is set to be larger than the size of the first molding die 610. The position control unit 630 controls the first molding die 6
By controlling the positions of the two molds 61,
Adjust the interval of 0,620.

In FIG. 5A, a lump (also called a gob) of molten glass G heated to about 1000 ° C. is placed on a second mold 620. In FIG. 5B, the position control unit 630 controls the first molding die 610, so that the first molding die 610 is moved to the second molding die 620.
Approach. At this time, the molten glass G is pressed to generate a glass block PG. After the glass block PG is sufficiently cooled, the position control unit 630 returns to FIG.
By controlling the first mold 610 in (C), the first mold 610 is separated from the second mold 620. Thereby, the press-formed glass block PG
Is obtained. Thereafter, by cutting off a surplus portion around the glass block PG, the lens array 1 shown in FIG.
40 can be obtained. The surplus part is, for example,
Using a diamond cutter, etc., the glass block PG
Can be cut by forming a cut line on the surface of the glass block and bending the glass block PG along the cut line.

The side surface (slope) of the outermost small lens 146o of the lens array 140 is
In FIG. 2, it is not used for light propagation. The reason why the slope is formed on the side surface of the outermost peripheral small lens 146o in the present embodiment is that the outermost peripheral small lens is formed in the same shape as the molding surface S1 of the first molding die 610 as described below. This is for forming the lens surface 146o.

FIG. 6 is an explanatory view showing, as a comparative example of FIG. 5, a manufacturing procedure of a lens array 140Z having different shapes of outermost small lenses. This manufacturing apparatus 600Z includes two molds 610Z and 620Z and a position control unit 6 as in FIG.
30Z, but the first mold 610Z is modified. Therefore, a lens array 14 different from that of FIG.
A glass block PGZ containing 0Z is manufactured. Specifically, the first mold 610 in FIG.
A side surface of the outermost small lens 146o of 0 has a molding surface S1 that can form a slope. On the other hand, the first mold 6 shown in FIG.
10Z is the outermost small lens 14 of the lens array 140Z.
The side surface of 6Zo has a molding surface S1Z that can form a planar side surface (side wall) perpendicular to the first surface B1 of the base portion 142Z.

When using the manufacturing apparatus 600Z, FIG.
As shown in (C), the boundary area between the lens surface of the outermost peripheral small lens 146Zo and the side wall is rounded, and it is relatively difficult to accurately form the lens surface of the outermost peripheral small lens 146Zo. This is because the molding surface S1Z of the first molding die 610Z is provided with a corner having a relatively sharp shape for molding the above-described boundary region of the outermost peripheral small lens 146Zo. This is because the molten glass G is hard to penetrate. If the lens array 140Z in FIG. 6 is used instead of the lens array 140 in FIG. 4, the outermost small lens 146Zo transmits light incident on the rounded area W to the second lens array 150 (FIG. 2). ) Can not be injected well. At this time, the illumination optical system 1
00 or the light use efficiency of the projector 1000 is reduced.

Therefore, in this embodiment, as shown in FIG. 5, a first molding die 610 having a molding surface S1 capable of molding a slope on the side surface of the outermost small lens of the lens array is used. On the molding surface S1 of the first molding die 610, since the shape of the corner for molding the boundary region of the outermost peripheral small lens is relatively gentle, the molten glass G enters the corner of the molding surface S1. It will be easier. As a result, the lens surface of the outermost peripheral small lens of the lens array can be accurately formed into the same shape as the molding surface of the mold.

As described above, the lens array 14
At 0, only the outermost small lens 146o has a side surface on a side not adjacent to other small lenses. In other words, the lens surfaces of two adjacent small lenses 146 are connected so as to be continuous, and a plane perpendicular to the first surface B1 of the base portion 142 is provided between the two adjacent small lenses. No side walls are present. For this reason, in the present embodiment, it is possible to accurately form the lens array in the same shape as the molding surface S1 of the first molding die 610.

FIG. 7 is an explanatory view showing a first modified example of a lens array which can be manufactured by press-molding molten glass. The lens array 440A shown in FIG.
This is almost the same as the lens array 140, but the shape of the side surface of the outermost peripheral small lens 446Ao is changed. Specifically, a curved inclined surface is formed on the side surface of the outermost peripheral small lens 446Ao toward the outer edge of the base portion 442A and obliquely intersecting the first surface B1 of the base portion 442A. This curved surface has a curvature different from that of the lens surface of the outermost peripheral small lens 446Ao.

FIG. 8 is an explanatory view showing a second modification of the lens array that can be manufactured by press-molding molten glass. The lens array 440B shown in FIG.
This is almost the same as the lens array 140, but the shape of the side surface of the outermost small lens 446Bo is changed. Specifically, similarly to FIG. 4, the side surface of the outermost peripheral small lens 446Bo faces the outer edge of the base portion 442B,
A planar inclined surface FS obliquely intersecting the first surface B1 of 2B is formed. However, the lens surface LS of the outermost peripheral small lens 446Bo and the planar inclined surface FS are smoothly connected by the connection surface CS. Note that the connection surface CS is a substantially spherical curved surface that is in contact with both the lens surface LS and the planar inclined surface FS.

The lens array 440A shown in FIGS.
Also when manufacturing 440B, two molds as shown in FIG. 5 are used. Then, even when the lens arrays 440A and 440B having the shapes shown in FIGS. 7 and 8 are manufactured, the lens arrays can be easily formed into the same shape as the molding surface of the mold. In the case where the lens array 440B including the connection surface CS shown in FIG. 8 is manufactured, the lens surface of the outermost small lens can be formed more accurately than the case where the lens array 140 shown in FIG. 4 is manufactured. There are advantages.

FIG. 9 is an explanatory view showing a third modification of the lens array that can be manufactured by press-molding molten glass. The lens array 440C shown in FIG.
Is substantially the same as the lens array 140 of FIG.
A concave lens surface is formed on the second surface B2 of 42C. In this case, the first surface B1 of the base portion 442C is formed.
It is possible to change the emission direction of the light emitted from each of the small lenses 446C formed at the same time. In FIG. 9, one lens surface is formed on the second surface B2 of the base portion 442C, but a plurality of small surfaces formed on the first surface B1 are formed on the second surface B2 of the base portion 442C. A plurality of small lenses corresponding to the lens 446C may be formed. That is, it is possible to form at least one lens surface on the second surface of the base portion.

FIG. 10 is an explanatory diagram showing a region where a slope is formed on the side surface of the outermost peripheral small lens of the lens array. In the drawing, a cross hatch is provided in a region where a slope is formed. FIG. 10A shows the lens array 140 of FIG. 4A, in which all the outermost small lenses 146o have slopes formed on the side surfaces. FIG.
In the lens array 140 'shown in FIG. 10B, the 20 outermost small lenses 1 excluding the four outermost small lenses formed at the four corners are shown.
A slope is formed on the side surface of 46o. Note that two side surfaces of each outermost small lens 146o formed at the four corners are:
It has surfaces (vertical surfaces) that are substantially orthogonal to each other and that are substantially orthogonal to the first surface B1 of the base portion 142. In the lens array 140 ″ of FIG.
As in (A), the slopes are formed on the side surfaces of all outermost small lenses 146o, but the slopes are formed only in the central region of the side surfaces. In addition, each outermost small lens 14
In the side surface of 6o where no slope is formed,
Surfaces (vertical surfaces) that are substantially perpendicular to each other and substantially perpendicular to the first surface B1 of the base portion 142 are formed.

As described above, in the lens arrays 140 'and 140 "shown in FIGS. 10B and 10C, the two side surfaces of each outermost small lens 146o formed at the four corners are substantially orthogonal to each other. , A plane (vertical plane) substantially perpendicular to the first plane B1 of the base portion 142. In the present embodiment, the two vertical planes are formed by a relatively smooth mold formed by press molding with a molding die. Plane.
If this molding surface is used as a reference surface of the lens array 140,
Processing such as cutting off the surplus portion of the glass block and positioning of the lens array can be easily performed.

As shown in FIG. 10B, it is not necessary for all the outermost small lenses 146o to have slopes formed on the side surfaces. Further, as shown in FIG. 10C, the slope may not be formed in all the regions on the side surface of the outermost peripheral small lens 146o. Generally, at least one outermost small lens 146 of the plurality of small lenses 146
It is sufficient that the side surface of “o” faces the outer edge of the base portion 142 and includes a slope that obliquely intersects one surface B1 of the base portion 142.

As described above, the lens array 140 of the present embodiment has the substantially plate-shaped base portion 142 and the base portion 1.
42, the plurality of small lenses 146 formed on one surface B1.
And a plurality of outermost small lenses 1 formed on the outermost circumference
Only 46o comprises a plurality of small lenses 146 having sides on the side not adjacent to other small lenses. The side surface of the outermost peripheral small lens 146o is
, And includes a slope obliquely intersecting with one surface B1 of the base portion 142. By adopting such a shape, the lens array can be formed in the same shape as the molding surface of the mold, so that the lens array can be accurately molded.

The manufacturing apparatus 600 of this embodiment includes two molds 610 and 620, and the first mold 6
Reference numeral 10 has a molding surface on which the outer shapes of the plurality of small lenses of the lens array can be molded. Such a molding die 61
By using 0,620, the lens array 140 can be formed in the same shape as the molding surface of the mold, and as a result, the lens array 140 can be molded with high accuracy. In the present embodiment, the position control unit 6
30 controls the position of the first mold 610,
Instead, the position of the second mold 620 may be controlled. Generally, the position control unit may adjust the distance between the two molds by controlling the position of at least one of the first and second molds.

Further, by using the lens array 140 of this embodiment, it is possible to improve the light use efficiency of the illumination optical system 100 and the projector 1000. As a result, in the illumination optical system 100, the intensity of light that illuminates the illumination area LA can be improved, and the projector 1
000, a brighter image can be projected and displayed on the screen SC.

The first lens array 140 described above is used.
The problem described above may similarly occur in the second lens array 150. However, the first lens array 140
Are emitted from the second lens array 1
Since it only enters a part of each of the 50 small lenses 156,
The above problem does not significantly affect the optical characteristics of the second lens array 150. Therefore, in the present embodiment, the present invention is applied only to the first lens array.

B. Second Embodiment FIG. 11 is an explanatory diagram showing a manufacturing procedure of a lens array 140A in a second embodiment. The manufacturing apparatus 600A of this embodiment is almost the same as the manufacturing apparatus 600 of FIG. 5, except that the second mold 620A and the position control unit 630A are changed. Specifically, the second molding die 620A includes a central molding portion 620Aa having a molding surface S2Aa for molding the central portion of the second surface L2 of the lens array 140A, and a second surface L2 of the lens array 140A. Molding surface S2A for molding the peripheral portion of
b. Then, the position control unit 630A controls the position of the first molding die 610A and controls the position of the second molding die 620A (specifically, the central molding part 620Aa).

In FIGS. 11A and 11B, FIGS.
As in (B), the molten glass G is separated into two molds 610
A, 620A. In FIG. 11C, the position control unit 630A causes the central molding unit 620Aa of the second molding die 620A to be closer to the first molding die 610A. In FIG. 11D, the position control unit 630A
Returns the position of the central molded portion 620Aa,
Is separated from the second molding die 620A. Thus, a press-formed glass block PGA is obtained. Thereafter, by cutting off the surplus portion of the glass block PGA, the lens array 140A can be obtained. The base 142 of the lens array 140A
A concave portion 143A is formed on the second surface B2 of A by the central molded portion 620Aa.

As shown, the central molding portion 620Aa has a molding surface S2Aa of substantially the same size as the region for molding the lens surfaces of the plurality of small lenses 146A of the first molding die 610A. For this reason, each small lens 146
The light incident on A is emitted from the bottom surface of the concave portion 143A without being emitted from the side wall of the concave portion 143A. As a result, the lens array 140A can emit light incident on each small lens 146A in a predetermined direction.

As described above, the position control unit 630A sets the distance between the first molding die 610A and the second molding die 620A to a predetermined size in FIG.
Further, in FIG. 11 (C), the distance between the first molding die 610A and the central molding part 620Aa of the second molding die 620A is reduced. Therefore, the molten glass G easily spreads along the molding surface S1A of the first molding die 610A, and the plurality of small lenses 146 of the lens array 140A are formed.
It becomes possible to mold the lens surface of A more accurately.

Note that, even when the second mold 620A of this embodiment is used, a lens array as shown in FIGS. 7, 8, and 9 can be manufactured. In addition, as shown in FIG. 9, when manufacturing a lens array in which a concave lens surface is formed on the second surface of the base portion, the center molding portion 620A
What is necessary is just to change the planar molding surface S2Aa of a into a convex molding surface.

C. Third Embodiment FIG. 12 is an explanatory view showing molding dies 610B and 620B in a third embodiment.
FIG. 12 (A-1) shows a plan view of the first molding die 610B, and FIG. 12 (A-2) shows a schematic cross-sectional view along the AA plane of FIG. 12 (A-1). ing. FIG.
2 (B-1) is a plan view of the second mold 620B, and FIG. 12 (B-2) is a plan view of the second mold 620B.
FIG. 3 shows a schematic cross-sectional view on the B plane.

The molding dies 610B and 620B of this embodiment are
The molding dies 610 and 620 (FIG. 5) of the first embodiment are almost the same, but the molding surface S1B of the first molding die 610B is formed around four rectangular regions for molding a plurality of small lenses. V-shaped protrusion 614B. The molding surface S2B of the second molding die 620B is the same as that of the first molding die 610B.
Four V-shaped protrusions 624B are provided at positions corresponding to the four V-shaped protrusions 614B provided in B.

FIG. 13 shows the molding dies 610B and 62 shown in FIG.
It is explanatory drawing which shows the glass block PGB including the lens array 140B produced using 0B. FIG. 13 (A)
1 shows a plan view of a glass block PGB, and FIG.
FIG. 3B is a schematic cross-sectional view taken along the line BB in FIG.

As shown, the glass block PGB
Has a substantially disk-shaped outer shape. In the glass block PGB, four pairs of V-shaped grooves (hereinafter, referred to as “V grooves”) V at the boundary between the lens array 140B and the surplus portion.
B1 and VB2 are formed in a substantially frame shape. In particular,
Four V-grooves VB on the first surface P1 of the glass block PGB
1 are formed, and four V-grooves VB2 are formed on the second surface P2.
Are formed. The position of the V-groove VB1 formed on the first surface P1 of the glass block PGB substantially matches the position of the V-groove VB2 formed on the second surface P2 of the glass block.

FIG. 14 shows the glass block PGB of FIG.
FIG. 9 is an explanatory diagram showing a lens array 140B obtained from FIG. FIG. 14A is a plan view of the lens array 140B, and FIG. 14B is a schematic cross-sectional view taken along a plane BB of FIG. 14A.

This lens array 140B is obtained by bending the glass block PGB shown in FIG. 13 along four pairs of V-grooves VB1 and VB2, thereby cutting off the surplus portion. In addition, the lens array 140B (base portion 142B)
Is a surface formed by cutting, and therefore has a relatively rough cut surface.

As described above, in the first and second molds 610B and 620B of FIG. 12, both surfaces P1 and P2 of the glass block PGB are substantially frame-shaped V-shaped at the boundary between the lens array 140B and the surplus portion. It has molding surfaces S1B and S2B having grooves VB1 and VB2. Therefore, by bending the glass block PGB along the substantially frame-shaped grooves VB1 and VB2, the surplus portion can be easily cut off to obtain the lens array 140B.

FIG. 15 is an explanatory view showing a first modification of the molding die in the third embodiment, and corresponds to FIG. First mold 610 shown in FIGS. 15 (A-1) and (A-2)
C is a mold 61 shown in FIGS. 12 (A-1) and 12 (A-2).
Same as 0B. The second mold 620C shown in FIGS. 15 (B-1) and (B-2) corresponds to FIGS.
The mold is almost the same as the mold 620B shown in FIG.
(B-1) A substantially frame-shaped peripheral region W hatched in FIG.
The thickness of Co is larger than the thickness of the rectangular central region WCi. And four V-shaped protrusions 624C
Are formed on the inner peripheral side of the substantially frame-shaped peripheral region WCo.

FIG. 16 shows the molding dies 610C and 62 shown in FIG.
FIG. 14 is an explanatory diagram showing a glass block PGC including a lens array 140C manufactured using 0C, and corresponds to FIG. This glass block PGC is almost the same as the glass block PGB of FIG. 13, but has V-grooves VC1 and VC2.
The thickness of the outer surplus portion is smaller than the thickness of the base portion 142C of the lens array 140C.

FIG. 17 shows the glass block PGC of FIG.
FIG. 15 is an explanatory diagram showing a lens array 140C obtained from FIG. 14 and corresponds to FIG. This lens array 140C
As in FIG. 14, the glass block PGC is obtained by cutting off a surplus portion. The side surface of the lens array 140C (base portion 142C) has a relatively smooth cut surface formed by press forming together with a relatively rough cut surface formed by cutting.

As described above, the second mold 62 of FIG.
0C has a molding surface S2C such that the thickness of the surplus portion of the glass block PGC is smaller than the thickness of the base 142C of the lens array 140C. Therefore,
Even when the thickness of the base 142C of the lens array 140C is relatively large, the surplus portion of the glass block PGC can be cut off relatively easily.

FIG. 18 is an explanatory view showing a second modification of the molding die in the third embodiment, and corresponds to FIG. First molding die 610 shown in FIGS. 18 (A-1) and 18 (A-2)
D is a mold 61 shown in FIGS. 15 (A-1) and (A-2).
Although almost the same as 0C, the molding surface S1D of the first molding die 610D includes four sets of columnar convex portions 615D. Each set of protrusions 615D has four V-shaped protrusions 61.
Each of the 4Ds is provided so as to be divided near four corners of a rectangular region for forming a plurality of small lenses. The second molding die 620D shown in FIGS. 18 (B-1) and (B-2) is almost the same as the molding die 620C shown in FIGS. 15 (B-1) and (B-2). Mold 620
The molding surface S2D of D is provided with four sets of cylindrical protrusions 625D at positions corresponding to the four sets of cylindrical protrusions 615D provided on the first molding die 610D. The four sets of convex portions 625D are provided at the boundary between the substantially frame-shaped peripheral region WDo and the rectangular central region WDi, and each set of convex portions 625D is provided.
25D is provided so as to divide each of the four V-shaped protrusions 624D formed on the inner peripheral side of the peripheral region WDo. Of the projections 624D, the partial projections 624Do near the four corners of the second mold 620D are provided at positions shifted outward from the central partial projection 624Di. The central partial projection 624Di is the first partial projection 624Di.
Are provided at positions corresponding to the protrusions 614D provided on the molding die 610D.

FIG. 19 shows the molding dies 610D and 62 shown in FIG.
FIG. 14 is an explanatory diagram showing a glass block PGD including a lens array 140D manufactured using 0D, and corresponds to FIG. This glass block PGD is almost the same as the glass block PGC of FIG. 16, but each V-groove VD1, VD
2, two columnar holes h are formed. Further, the position of the V groove VD2 formed on the second surface P2 of the glass block PGD is located outside the position of the groove VD1 formed on the first surface P1 of the glass block PGD at the four corners of the base portion 142D. It is out of alignment. At the center of each side of the base portion 142D, as in FIG. 16, the V-groove V formed on the second surface P2 of the glass block PGD.
The position of D2 substantially coincides with the position of V-groove VD1 formed in first surface P1 of glass block PGD.

FIG. 20 shows the glass block PGD of FIG.
FIG. 15 is an explanatory diagram showing a lens array 140D obtained from FIG. This lens array 140D
As in FIG. 17, the surplus portion of the glass block PGD is obtained by cutting off the surplus portion, but since the thickness of the surplus portion of the glass block PGD is relatively small, the surplus portion can be cut off relatively easily. Lens array 140D
The side surface of the central portion of each side of the (base portion 142D) is shown in FIG.
Like FIG. 7 (B), it has a cut surface and a molding surface.
As shown in FIG. 20B, the side surfaces of the four corners of the lens array 140D (base portion 142D) have a cut surface and a molding surface, but the cut surface is formed obliquely.

As described above, the second mold 62 shown in FIG.
0D also has a molding surface S2D such that the thickness of the surplus portion of the glass block PGD is smaller than the thickness of the base portion 142D of the lens array 140D. Therefore,
Even when the thickness of the base portion 142D of the lens array 140D is relatively large, the surplus portion of the glass block PGD can be relatively easily cut off.

In FIGS. 15 and 18, the thickness of the surplus portions of the glass blocks PGC and PGD is changed depending on the shape of the molding surfaces S2C and S2D of the second molding dies 620C and 620D. Molding surface S of mold 610C
You may make it change by the shape of 1C. Generally, at least one of the first and second molding dies only needs to have a molding surface such that the thickness of the surplus portion of the glass block is smaller than the thickness of the base portion.

When assembling the illumination optical system 100 and the projector 1000, the lens array is usually mounted on a base frame or the like. At this time, if the side surface of the lens array is rough, it is relatively difficult to position the lens array on the base frame. 17 and FIG. 20, the lens array 140C, 1
40D (base portions 142C and 142D) includes a molding surface formed by press molding on a side surface thereof. In other words, the second mold 620 shown in FIGS.
In C and 620D, the side surfaces at the four corners of the base portions 142C and 142D of the lens arrays 140C and 140D are substantially orthogonal to each other, and the base portions 142C and 142D.
The molding surfaces S2C and S2D include a molding surface that is substantially perpendicular to the first surface B1. Therefore,
If the molding surfaces included in the side surfaces at the four corners of the base portion are used as reference surfaces of the lens array, the lens array can be easily positioned.

In FIGS. 15 and 18, the molding surfaces S2C and S2D of the second molding dies 620C and 620D are used.
Although molding surfaces are formed on the four side surfaces of the four corners of the base portions 142C and 142D, the first molding dies 610C and 61D are formed.
It may be formed by the molding surfaces S1C and S1D of 0D. In general, at least one of the first and second molds has side surfaces at four corners of the base portion,
What is necessary is just to have a molding surface which is substantially perpendicular to each other and includes a molding surface which is substantially perpendicular to one surface of the base portion.

The lens array 14 shown in FIGS.
As can be seen by comparing 0C and 140D, in the lens array 140D, the cut surface is formed inside the molding surface. In other words, the first and second molds 610D and 620D of FIG. 18 are configured such that the position of the V-groove VD2 formed in the second surface P2 of the glass block PGD is at least at the four corners of the base 142D. PGD
The molding surfaces S1D and S2D are shifted outside the position of the V groove VD1 formed on the first surface P1.
Therefore, if the molding surface included in the side surface at the four corners of the base portion is set as the reference surface of the lens array, the cut surface formed when the surplus portion is cut off is prevented from protruding outside the molding surface. As a result, the positioning of the lens array can be performed more easily.

D. Fourth Embodiment: When a glass block is produced using a mold, the glass block may be difficult to separate from the mold. For example, the manufacturing apparatus 6 shown in FIG.
When 00 is used, the glass block PG is hard to separate from the first mold 610. This is because the first mold 610
Is an uneven molding surface S1 for molding a plurality of small lenses
It is because it has. Therefore, in this embodiment, the glass block is devised so that it can be easily separated from the mold.

FIG. 21 is an explanatory view showing the procedure for manufacturing the lens array 140E in the fourth embodiment. The manufacturing apparatus 600E of this embodiment is almost the same as the manufacturing apparatus 600 of FIG. 5, except that the first molding die 610E is changed. Specifically, the first molding die 610E includes a cylindrical mold release portion 61 around a rectangular region for molding a plurality of small lenses.
8E. The release part 618E is provided in the first mold 6
It can protrude from the molding surface S1E of 10E toward the molding surface S2E of the second molding die 620E. And the position control part 630E controls the whole position of the 1st shaping | molding die 610E, and controls the individual position of the mold release part 618E. Although FIG. 21 shows two release parts 618E, four are actually prepared. However, in general, at least one release part 618E may be provided.

In FIGS. 21A and 21B, FIGS.
As in (B), the molten glass G is separated into two molds 610
E, 620E. FIG. 21 (C)
Then, when separating the first molding die 610E from the second molding die 620, the position control unit 630E causes the release part 618E to protrude from the molding surface S1E of the first molding die 610E. Thereby, the press-formed glass block PGE is
It can be easily separated from the first mold 610E.

The release part 61 of the first molding die 610E
Around 8E, in order to make the release part 618E protrude,
A slight gap is provided. Then, when the molten glass G is pressed, the molten glass G may slightly enter into the gap, and burrs may be generated on the surface of the glass block PGE as shown in FIG. is there. In such a case, the first area is set to be relatively thinner than the surrounding area in contact with the release portion of the glass block PGE.
The shape of the molding surface S1E of the molding die 610E may be changed. By doing so, it is possible to prevent burrs from projecting above the first surface B1 of the base portion 142E of the lens array 140E. In the case where the area where burrs are generated is cut off as a surplus part, the above measures are not necessary.

It should be noted that the present invention is not limited to the above examples and embodiments, but can be implemented in various modes without departing from the gist of the invention.
For example, the following modifications are possible.

(1) In the above embodiment, the second surface B2 of the base portion 142 of the first lens array 140 is a surface to be molded formed by two molding dies.
For example, when the thickness of the base portion 42 is relatively large,
May be ground.

(2) In the above embodiment, the plurality of small lenses 146 of the first lens array 140 are arranged in a matrix on the base portion 142. May be arranged.

In the above-described embodiment, an eccentric lens is used as the plurality of small lenses 146 of the first lens array 140, but a non-eccentric lens may be used instead. In addition, the cross section of the lens array taken along the plane BB and the plane CC in FIG. 4A has a shape as shown in FIG. 4C. Therefore, also in this case, the lens surfaces of the two adjacent small lenses are connected so as to be continuous.

That is, the present invention is applicable to a lens array in which, of the plurality of small lenses, only the outermost small lens has a side surface that is not adjacent to other small lenses.

(3) Although molten glass is used in the above embodiment, for example, molten plastic may be used instead. In general, the lens array may be manufactured by press-molding a molten optical material.

(4) In the above embodiment, the illumination optical system 100
Has a polarization generation optical system 160, but if it is not necessary to generate polarized light, the polarization generation optical system 160 may be omitted. The illumination optical system 100 includes a second lens array 150 and a superimposing lens 17 as a superimposing optical system.
Although 0 is provided, if light incident on one of the optical components can be superimposed on the illumination area LA, the other optical component may be omitted. Further, the light source device 120 emits a substantially parallel light beam. Alternatively, the light source device 120 may emit a convergent light or a divergent light.

In general, an illumination optical system includes a light source device, a lens array for dividing a light beam emitted from the light source device into a plurality of partial light beams, and a plurality of partial light beams superimposed on a predetermined illumination area. And a superimposing optical system for performing the operation.

(5) In the above embodiment, the projector 10
Reference numeral 00 denotes a transmissive liquid crystal panel as an electro-optical device. Alternatively, a reflective liquid crystal panel may be provided. Further, instead of the liquid crystal panel, a micromirror type light modulation device may be provided. As a micro-mirror type optical modulator, for example, DMD
(Digital micromirror device) (Trademark of TI)
Can be used. In general, any electro-optical device may be used as long as it modulates light from an illumination optical system in accordance with image information.

(6) In the above embodiment, the projector 1000 for displaying a color image has been described as an example, but the same applies to a projector for displaying a monochrome image.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an example of a projector to which the present invention has been applied.

FIG. 2 is an explanatory diagram showing the illumination optical system 100 of FIG. 1 in an enlarged manner.

FIG. 3 is an explanatory diagram showing an enlarged view of a first polarization generating element array 160A in FIG. 2;

FIG. 4 is an explanatory diagram showing an enlarged view of a first lens array 140 of FIG. 2;

FIG. 5 is an explanatory diagram showing a manufacturing procedure of the lens array 140 of FIG.

FIG. 6 is an explanatory view showing a manufacturing procedure of a lens array 140Z in which the shape of the outermost small lens is different as a comparative example of FIG.

FIG. 7 is an explanatory view showing a first modified example of a lens array that can be manufactured by press-molding molten glass.

FIG. 8 is an explanatory view showing a second modified example of a lens array that can be manufactured by press-molding molten glass.

FIG. 9 is an explanatory view showing a third modification of the lens array that can be manufactured by press-molding molten glass.

FIG. 10 is an explanatory diagram showing a region where a slope is formed on a side surface of the outermost peripheral small lens of the lens array.

FIG. 11 is an explanatory diagram showing a manufacturing procedure of the lens array 140A in the second embodiment.

FIG. 12 shows molds 610B and 620 according to the third embodiment.
It is explanatory drawing which shows B.

FIG. 13 is an explanatory diagram showing a glass block PGB including a lens array 140B manufactured using the molds 610B and 620B of FIG.

FIG. 14 is an explanatory diagram showing a lens array 140B obtained from the glass block PGB of FIG.

FIG. 15 is an explanatory view showing a first modification of the molding die in the third embodiment, and corresponds to FIG.

FIG. 16 is an explanatory diagram showing a glass block PGC including a lens array 140C manufactured using the molds 610C and 620C of FIG. 15, and corresponds to FIG.

17 is an explanatory diagram showing a lens array 140C obtained from the glass block PGC in FIG. 16, and corresponds to FIG.

FIG. 18 is an explanatory view showing a second modification of the molding die in the third embodiment, and corresponds to FIG.

FIG. 19 is an explanatory view showing a glass block PGD including a lens array 140D manufactured using the molds 610D and 620D of FIG. 18, and corresponds to FIG.

20 is an explanatory diagram showing a lens array 140D obtained from the glass block PGD in FIG. 19, and corresponds to FIG.

FIG. 21 is an explanatory diagram showing a manufacturing procedure of the lens array 140E in the fourth embodiment.

[Explanation of symbols]

1000 Projector 100 Illumination optical system 100ax System optical axis 120 Light source device 122 Lamp 124 Reflector 126 Parallelizing lens 140, A, B, C, D, E, Z First lens array 142 A, B, C, D, E, Z: base portion 143A: concave portion 146, A, E: first small lens 146i: inner small lens 146o, Zo: outermost small lens 150: second lens array 156: second small lens 160: polarization generating optical system 160A, 160B: polarization generating element array 162: light shielding plate 162a: aperture surface 162b: light shielding surface 164: polarization beam splitter array 164a: polarization separation film 164b: reflection film 164c ... Glass material 166 .lambda. / 2 retardation plate 170 Superimposing lens 200 Color light separation optical system 220 Relay optical system 3 0R, 300G, 300B Liquid crystal light valve 320 Cross dichroic prism 340 Projection optical system 440A, B, C First lens array 442A, B, C Base part 446C First small lens 446Ao, Bo Outer peripheral small lens 600, A, E, Z ... Manufacturing apparatus 610, A, B, C, D, E, Z ... First molding die 614B, C, D ... Protrusion 615D ... Convex part 618E ... Release part 620 , A, B, C, D, E, Z: second molding die 620Aa: central molding portion 620Ab: peripheral molding portion 624B, C, D: projection portion 625D: convex portion 630, A, E, Z: position control Portions PG, A, B, C, D, E, Z: glass block B1: first surface of base portion B2: second surface of base portion L1: first surface of lens array L2: first surface of lens array Side 2 P1 ... First surface of glass block P2: second surface of glass block S1, A, B, C, D, E, Z: molding surface of first molding die S2, Aa, Ab, B, C, D, E, Z: molding surface of second molding die VB1, VB2, VC1, VC2, VD1, VD2,.
Groove G: molten glass LA: lighting area SC: screen

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) G03B 21/14 G03B 21/14 Z (72) Inventor Hiroshi Kojima 3-5-5 Yamato, Suwa-shi, Suwa-shi, Nagano F term in Seiko Epson Corporation (reference) 2H091 FA26X FA26Z FA29Z FC17 FC19 LA16 MA07

Claims (17)

[Claims] 1. A lens array manufactured by press-molding a molten optical material, comprising: a substantially plate-shaped base portion; and a plurality of small lenses formed on one surface of the base portion. Only the outermost outermost small lenses formed on the outermost periphery have a side surface on a side that is not adjacent to the other small lenses, and the plurality of small lenses, wherein the side surface of at least one of the outermost outermost small lenses is A lens array including a slope facing an outer edge of the base portion and obliquely intersecting the one surface of the base portion. 2. The lens array according to claim 1, wherein the slope is a plane. 3. The lens array according to claim 1, wherein the inclined surface is a curved surface having a curvature different from a curvature of a lens surface of the outermost lens. 4. The lens array according to claim 1, wherein the inclined surface includes a flat surface and a connecting surface that smoothly connects the flat surface and the lens surface of the outermost peripheral small lens. 5. The lens array according to claim 1, wherein at least one lens surface is formed on the other surface of the base portion. 6. The lens array according to claim 1, wherein the plurality of small lenses are formed in a matrix, and the outermost small lenses formed at four corners among the plurality of outermost small lenses. A lens array, wherein the two side surfaces of the lens are substantially orthogonal to each other and include a molding surface substantially orthogonal to the one surface of the base portion. 7. The lens array according to claim 1, wherein the base portion has a substantially rectangular outer shape, and two side surfaces at four corners of the base portion are substantially orthogonal to each other. A lens array including a molding surface substantially orthogonal to the one surface of the base portion. 8. An illumination optical system, comprising: a light source device; a lens array for dividing a light beam emitted from the light source device into a plurality of partial light beams; An illumination optical system, comprising: a superimposing optical system for superimposing on a region, wherein the lens array is the lens array according to any one of claims 1 to 7. 9. A projector for projecting and displaying an image, comprising: an illumination optical system; an electro-optical device that modulates light from the illumination optical system according to image information; and a modulated light obtained by the electro-optical device. A projection optical system for projecting, the illumination optical system comprising: a light source device; a lens array for dividing a light beam emitted from the light source device into a plurality of partial light beams; and the plurality of partial light beams And a superimposing optical system for superimposing on the electro-optical device, wherein the lens array is the lens array according to any one of claims 1 to 7. 10. A manufacturing apparatus for manufacturing a lens array by press-molding a molten optical material, comprising: a first surface for forming a first surface including a lens surface of a plurality of small lenses of the lens array. A first mold, a second mold for molding a second surface of the lens array, and a position of at least one of the first and second molds. A position control unit for adjusting an interval between the first mold and the second mold; wherein the lens array is formed on a substantially plate-shaped base and on one surface of the base; The plurality of small lenses, only the plurality of outermost small lenses formed at the outermost periphery,
A plurality of small lenses having side surfaces on a side not adjacent to other small lenses, wherein the side surface of at least one outermost small lens faces an outer edge of the base portion, and the one side of the base portion. A manufacturing apparatus, comprising: a slope that obliquely intersects a surface of the plurality of small lenses, wherein the first molding die has a molding surface capable of molding the outer shapes of the plurality of small lenses. 11. The manufacturing apparatus according to claim 10, wherein the second molding die comprises: a central molding part for molding a central part of the second surface of the lens array; A peripheral molding portion for molding a peripheral portion of the second surface, wherein the central molding portion is substantially equal to a region for molding the lens surfaces of the plurality of small lenses of the first molding die. After having a molding surface of the same size, the position control unit sets the distance between the first molding die and the second molding die to a predetermined size, and then further performs the first molding A manufacturing apparatus for reducing a distance between a mold and the central molding portion of the second molding die. 12. The manufacturing apparatus according to claim 10, wherein the optical material block molded by the first and second molds has the lens array having the substantially rectangular base portion and a surplus around the lens array. The first and second molding dies, wherein both surfaces of the optical material block have a molding surface having a substantially frame-shaped groove at a boundary between the lens array and the surplus portion. apparatus. 13. The manufacturing apparatus according to claim 12, wherein at least one of the first and second molds has a thickness of the surplus portion of the optical material block larger than a thickness of the base portion. A manufacturing apparatus having a molding surface that becomes smaller. 14. The manufacturing apparatus according to claim 13, wherein at least one of the first and second molding dies is such that the surplus portion of the optical material block extends along the substantially frame-shaped groove. A manufacturing apparatus, wherein when cut off, side surfaces at four corners of the base portion have molding surfaces that are substantially perpendicular to each other and include a molding surface that is substantially perpendicular to the one surface of the base portion. 15. The manufacturing apparatus according to claim 14, wherein in the first and second molds, a position of a groove formed on one surface of the optical material block is the other of the optical material block. A manufacturing apparatus having a molding surface that substantially matches the position of the groove formed on the surface of the substrate. 16. The manufacturing apparatus according to claim 14, wherein in the first and second molds, a position of a groove formed on one surface of the optical material block is at least four corners of the base portion. 2. The manufacturing apparatus according to claim 1, further comprising a molding surface that is shifted outside a position of a groove formed on the other surface of the optical material block. 17. The manufacturing apparatus according to claim 10, wherein the first molding die is configured to separate the molded optical material block from the first molding die. From the molding surface, the second
The manufacturing apparatus provided with at least one release part protrudable toward the molding surface of the molding die of (1).