JP2002236317A - Illuminator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the effective utilization of illuminating light by reducing the wasted illuminating light by optimally setting the projection range of the illuminating light projected to a body to be illuminated in accordance with the breadth and length size of the body to be illuminated. SOLUTION: By using a 1st lens array set 5 where cylindrical lens arrays 5a and 5b are arranged in a direction orthogonal to each other and a 2nd lens array set 6 where cylindrical lenses 6a and 6b are arranged in a direction orthogonal to each other as a 1st lens array and a 2nd lens array constituting what is called an integrator optical system, the setting of the projection range of the illuminating light to the body to be illuminated 1 is optimized in accordance with the dimension of the breadth and length of the body to be illuminated 1, so that the wasted illuminating light is reduced to realize the effective utilization of the illuminating light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video projection apparatus having a rectangular illuminated object such as a liquid crystal panel, and the like.
The present invention relates to a lighting device suitable for illuminating the illuminated object.

[0002]

2. Description of the Related Art As an illumination optical system for uniformly illuminating a rectangular object to be illuminated such as a liquid crystal panel, a conventional illumination optical system has been proposed.
An integrator optical system combining two lens arrays is known, for example, from Japanese Patent Application Laid-Open No. 3-111806.

The integrator optical system disclosed in the publication discloses a first lens plate in which a plurality of lenses are arranged in an array on an XY plane, and a plurality of lenses corresponding to the first lens plate on an X'-Y 'plane. And a second lens plate arranged in an array, and provided with a superimposing lens for superimposing a plurality of luminous fluxes formed on the illuminated body. Then
In general, the projected image is rectangular, but the illuminance at the edges of the horizontal (X) and vertical (Y) does not rise from the surrounding zero state to a constant illuminance, so that there is a certain inclination. With this, a steady illuminance state is set.

On the other hand, in a general image projection apparatus (liquid crystal projector) using a liquid crystal panel of a type that modulates polarized light as an illuminated object, only one kind of polarized light of P-polarized light or S-polarized light can be used. In the case of a light source that emits randomly polarized light, about half of the illumination light generated from the light source is not used, and the utilization efficiency of the illumination light deteriorates. Various types of polarization conversion structures have been proposed for increasing the utilization efficiency of the illumination light.

The principle is that random polarized light is separated into two orthogonal polarized lights (P-polarized light and S-polarized light), and then one of the polarized lights is rotated 90 ° by a half-wave plate or the like, and the other is rotated. The polarized light is polarized in the same direction as the polarized light, and the optical axes of the two are aligned. Therefore, for example, the polarization directions can be aligned by a polarization conversion optical system structure in which a polarization beam splitter and a right-angle prism are provided side by side and a half-wave plate is arranged on the exit surface side of the polarization beam splitter or the right-angle prism. In this case, in order to enhance the conversion efficiency, light from the light source side is converged on the working surface (45 ° dielectric multilayer film) of the polarizing beam splitter by a lens plate, for example, as disclosed in JP-A-7-294906. It is proposed by the gazette.

On the other hand, in a configuration in which the polarizing beam splitter and the right-angle prism are simply provided side by side, the width or length of the entire optical system becomes about twice, and an extremely large projection lens having a small F number is required. Regarding the point that it must be used, see the above-mentioned JP-A-3-111.
An example of a configuration combining an integrator optical system disclosed in Japanese Patent Application Laid-Open No. 806 is proposed, for example, in Japanese Patent Application Laid-Open No. 8-304739. In general, a plurality of minute light beams (secondary light source images) are formed by a first lens array including a plurality of minute rectangular condensing lenses, and these light beams are converted into P light beams having different polarization directions. After being separated into polarized light and s-polarized light, one of the polarized lights is rotated to emit light with the polarization planes aligned. In other words, by separating the polarized light using the process of generating a minute secondary light source image, which is a feature of the integrator optical system, the spatial spread of the optical path due to the polarized light separation is suppressed. It was done.

Further, according to Japanese Patent Application Laid-Open No. H10-16065, the parallel light from the light source side is once condensed by a convex lens and then collimated again so that the beam diameter is reduced to about half and the polarization conversion structure is obtained. Have been proposed to reduce the size of the polarization conversion structure and the integrator optical system substantially.

[0008]

Problems to be Solved by the Invention
No. 06, a plurality of lenses are XY
When the lens plates arranged in an array on a plane or an X′-Y ′ plane are used, they are designed to illuminate a wider area having a certain width than the periphery of a required illumination target, and the surrounding rise is poor. Since the luminous flux of the portion is discarded, the illumination light is wasted.

In addition, as shown in Japanese Patent Application Laid-Open No. H8-304739, when a polarization aligning means is arranged after the second lens array in order to align polarized light, the focal point of the second lens array becomes X. , And Y directions can be located near the polarization alignment means, so that the light energy increases near the focal point, and the polarization energy means tends to deteriorate due to the influence of the light energy.

SUMMARY OF THE INVENTION It is an object of the present invention to set a projection range of illumination light projected on an illuminated object optimally according to the horizontal and vertical sizes of the illuminated object, and to waste illumination light. The aim is to reduce illumination and to make effective use of illumination light.

Another object of the present invention is to suppress the deterioration of the polarization converter due to the influence of light energy.

[0012]

According to a first aspect of the present invention, there is provided an illumination device, comprising: an illumination light generation device; and an illumination light generated by the illumination light generation device is arranged on an optical path on which an object to be illuminated is projected. A first lens array set in which a cylindrical lens array in which a plurality of cylindrical lenses are arranged in an X direction and a cylindrical lens array in which a plurality of cylindrical lenses are arranged in a Y direction orthogonal to the X direction are arranged in front and behind; A cylindrical lens array including a plurality of cylindrical lenses arranged near the focal point corresponding to one of the first lens array sets and a cylindrical lens array of the other of the first lens array set; , Which is composed of a plurality of cylindrical lenses placed near the focal point corresponding to A second lens array set in which a plurality of lens arrays are arranged in front and behind, and the illuminated object after each of a plurality of light beams generated by the first and second lens array sets pass through the second lens array set. And a bending lens that bends so as to overlap and project over the entire surface of the lens.

Therefore, a first lens array set and a second lens array set in which cylindrical lens arrays are arranged in orthogonal directions are used as the first lens array and the second lens array constituting a so-called integrator optical system. Thereby, when projecting the illumination light onto the illuminated object, the setting of the projection range can be optimized according to the vertical and horizontal dimensions of the illuminated object, the wasted illumination light is reduced, and the illumination light is effectively used. It can be used.

According to a second aspect of the present invention, in the lighting device according to the first aspect, the superimposing lens has a cylindrical surface corresponding to the X direction and the Y direction.

Therefore, the illumination light passing through the first and second lens array sets is bent by the superimposing lens, so that the illumination light is not wasted due to the bending, and the effective use of the illumination light is further achieved. be able to.

According to a third aspect of the present invention, in the illuminating device according to the first or second aspect, the superimposing lens is disposed close to a side of the second lens array set facing the object to be illuminated. .

Therefore, the illumination light that has passed through the second lens array set can be bent by the superimposing lens and projected onto the illuminated object before it spreads, and the optical path width between the second lens array set and the illuminated object can be increased. Therefore, when optical elements are interposed in the optical path, the optical elements can be reduced in size, and the occurrence of uneven illuminance on the illuminated object can be suppressed.

According to a fourth aspect of the present invention, in the lighting device according to the first or second aspect, the superimposing lens is disposed at a substantially intermediate position between the second lens array set and the illuminated body.

Therefore, the illumination light that is bent by the superimposing lens and projected onto the object to be illuminated is converted into substantially parallel light for each light beam divided by the first lens array set and the second lens array set. Thus, the illumination light can be projected onto the illuminated object without providing a condenser lens or the like for narrowing the illuminating light immediately before the illuminated object.

The invention according to claim 5 is the invention according to claims 1 to 4.
In the illumination device according to any one of the above, a polarization converter is disposed between the two cylindrical lens arrays in the second lens array set.

Therefore, only one of the cylindrical lens arrays can be focused near the polarization converter.
The influence of the light energy, which increases when the illumination light is collected at the focal point, on the polarization converter is reduced, and the deterioration of the polarization converter due to the influence of the light energy can be prevented.

The invention according to claim 6 is the invention according to claims 1 to 4.
In the illumination device according to any one of the above, a polarization converter is disposed on a side of the first lens array set facing the illumination light generation device.

Therefore, in carrying out any one of the first to fourth aspects of the present invention, either the P-polarized light component or the S-polarized light component obtained by performing the polarization conversion can be used. In addition, the influence of light energy, which increases when the illumination light is condensed by the first and second lens array sets, does not affect the polarization converter, and the deterioration of the polarization converter due to the influence of light energy can be prevented.

According to a seventh aspect of the present invention, in the illumination device according to the sixth aspect, a convex cylindrical lens and a concave cylindrical lens are arranged between the illumination light generating device and the polarization converter. .

Therefore, the illumination light generated by the illumination light generator can be efficiently taken into the polarization converter, and the illumination light can be effectively used.

According to a ninth aspect of the present invention, in the illuminating device according to any one of the first to seventh aspects, the illuminating light generating device includes a light emitting lamp and a reflecting mirror arranged so as to surround the light emitting lamp. And a plane mirror having a window for allowing the light reflected by the reflecting mirror to travel in a Z direction orthogonal to the X direction and the Y direction.

Therefore, almost all of the illumination light generated by the illumination light generator can be converted into parallel light before being taken into the first and second lens array sets, whereby the illumination light can be effectively used. it can.

[0028]

FIG. 1 shows a first embodiment of the present invention.
A description will be given based on FIG. FIG. 1 is an optical system configuration diagram showing a lighting device, and FIG. 2 is a perspective view showing a part of the optical system configuration.

This illumination device A1 projects illumination light onto a liquid crystal panel 1 which is a rectangular illuminated object having a horizontal and vertical aspect ratio of 4: 3. The illumination light generation device 2 and the integrator optical system 3. On the front surface of the liquid crystal panel 1, a condenser lens 4 for condensing light on each liquid crystal element of the liquid crystal panel 1 is provided.

In this embodiment, the integrator optical system 3 includes a plurality of cylindrical lenses in one direction (X direction).
And a cylindrical lens array 5 in which a plurality of cylindrical lens lenses are arranged in one direction (Y direction) orthogonal to the direction.
b, a first lens array set 5 arranged in front of and behind, a cylindrical lens array 6a in which a plurality of cylindrical lenses are arranged in one direction (X direction), and a plurality of cylindrical lens lenses in one direction orthogonal to the direction ( It comprises a second lens array set 6 arranged in front of and behind a cylindrical lens array 6b arranged in the (Y direction), and a superimposing lens 7 arranged immediately after the second lens array set 6.

A first lens array set 5 located on the side of the illumination light generating device 2 corresponds to a first lens array of a so-called integrator optical system, and the first lens array set 5 is provided with a horizontal and vertical (X, The number of secondary light source images corresponding to the multiplication number of Y) is divided and formed. The second lens array set 6 corresponds to a second lens array of a so-called integrator optical system, and has the same structure as the first lens array set 5.

The superimposing lens 7 is a lens having a cylindrical surface corresponding to the X direction and the Y direction. After the optical axis of the light beam generated by the first lens array set 5 passes through the second lens array set 6, The light beams split by the cylindrical lens are arranged so as to be refracted in a direction in which the light beams are superimposed on the entire surface of the liquid crystal panel 1 and projected. Note that a general convex lens may be used as the superimposing lens 7.

The illuminating light generating device 2 includes a light emitting lamp 8, a reflecting mirror 9 disposed so as to surround the light emitting lamp 8, and a light reflected by the reflecting mirror 9. Window 1 that advances in the direction of lens array set 5 (Z direction)
0a, and a UV / IR cut filter 11 for cutting off ultraviolet rays and infrared rays. The reflecting mirror 9 is formed in the shape of a paraboloid of revolution, and the light emitting lamp 8 is arranged near the focal point.

In such a configuration, after the light emitted from the light emitting lamp 8 is reflected by the reflecting mirror 9 and the plane mirror 10, only the substantially parallel illumination light is directed from the window 10a to the integrator optical system 3. The light is emitted and the UV / IR cut filter 11 cuts the ultraviolet light and the infrared light.
That is, the illumination light generator 2 generates illumination light in which ultraviolet rays and infrared rays are cut off, and furthermore, it is generated as parallel light.

The illumination light generated from the illumination light generator 2 is
The light is incident on the first and second lens array sets 5 and 6, and a large number of 2
The next light source image is divided and formed. These secondary light source images are bent so that their optical axes are directed toward the center of the liquid crystal panel 1 by the superimposing lens 7, and each secondary light source image is
It is projected in a superimposed form. At this time, since the light-emitting lamp 8 actually has a certain volume instead of a point light source, each secondary light source image also has a volume instead of a point light source. By arranging the second lens array set 6 at the position where is formed, the convergence can be enhanced and the projection toward the liquid crystal panel 1 can be performed, and a favorable projection state can be obtained.

FIG. 3 shows the illuminance distribution on the liquid crystal panel 1 as X.
Axis and the Y axis. x and y show the case of the integrator optical system of the conventional example as described in JP-A-3-111806, and x and y 'show the case of the integrator optical system 3 of the present embodiment. This is an example in which the X direction is adjusted to an optimum value. In the conventional example, when the illuminance in the X direction is set to be the optimum value, the rising of the edge portion in the Y direction becomes worse, the illumination range in the Y direction is widened, and the luminous flux of the portion with the bad rising is discarded. Therefore, illumination light is wasted. On the other hand, according to the present embodiment, as shown by y ′, the rising of the edge portion in the Y direction becomes sharp, the light flux discarded due to the poor rising of the illuminance is reduced, and the waste of illumination light is reduced.

Since the superimposing lens 7 is arranged close to the position immediately after the second lens array set 6, the superimposing lens 7 is moved before the illumination light passing through the second lens array set 6 spreads.
And the liquid crystal panel 1 can be bent. Thereby, the second lens array set 6 and the liquid crystal panel 1
Therefore, when optical elements are interposed in the optical path, the optical elements can be made smaller and the occurrence of illuminance unevenness on the liquid crystal panel 1 can be suppressed.

Further, since the superimposing lens 7 has a cylindrical surface corresponding to the X direction and the Y direction, the illumination light passing through the second lens array set 6 is bent by the superimposing lens 7, thereby causing the bending. Waste of the illumination light hardly occurs, and the effective use of the illumination light can be further achieved.

Further, according to the present embodiment, a cylindrical lens array 5a is used instead of the first lens array of a so-called integrator optical system for forming a secondary light source image serving as a virtual light source for illuminating the liquid crystal panel 1. , 5b, and cylindrical lens arrays 6a, 6b are used in place of the second lens array of the so-called integrator optical system for reducing the spread of the secondary light source image. Since the second lens array set 6 is used, as is apparent from FIG. 2, the required number of lenses is from m × n = 4 × 5 = 20 to m + n = 4 + 5 = 9.
And each cylindrical lens array 5a,
5b, 6a, and 6b have an array structure of cylindrical lenses simply arranged in one direction, so that their manufacture is easy. Further, the cylindrical lens arrays 5a and 5b (6
The combination of a and 6b) can deal with the horizontal and vertical aspect ratios of the liquid crystal panel 1, so that it is easy to deal with the aspect ratio.

Further, according to the present embodiment, since the illumination light generator 2 has the plane mirror 10 and the reflection mirror 9 having the window 10a, only the illumination light that has passed through the window 10a and has become parallel light is The light can be made incident on the one-lens array set 5, whereby the illumination light can be effectively used.

A second embodiment of the present invention will be described with reference to FIG. The same parts as those of the other embodiments described earlier are denoted by the same reference numerals, and description thereof will be omitted (the same applies to the following embodiments).

In the illuminating device A2 of the present embodiment, the superimposing lens 7 whose focal length is approximately 略 of the distance between the second lens array set 6 and the liquid crystal panel 1 is connected to the second lens array set 6 and the liquid crystal. It is arranged at a substantially intermediate position with the panel 1. Also,
In the first embodiment, the condenser lens 4 attached to the front surface of the liquid crystal panel 1 is omitted.

In such a configuration, the illumination light that has passed through the second lens array set 6 spreads until it reaches the superimposing lens 7, is bent by the superimposing lens 7, becomes parallel light, and is projected on the liquid crystal panel 1. For this reason, the condenser lens 4 that is located in front of the liquid crystal panel 1 and narrows down the illumination light projected on the liquid crystal panel 1 as described in the first embodiment is not required. Note that a normal convex lens may be used as the superimposing lens 7.

FIGS. 5 and 6 show a third embodiment of the present invention.
It will be described based on. The lighting device A3 of the present embodiment includes:
Between the cylindrical lens array 6a and the cylindrical lens array 6b in the second lens array set 6,
A polarization converter 12 for aligning a random light beam with only one polarized light (P-polarized light or S-polarized light) is provided.

The polarization converter 12 includes a light shielding plate array 13 and
It comprises a PBS (polarizing beam splitter) array 14 and a half-wave plate array 15.

The PBS array 14 is formed by arranging a plurality of PBS prisms on a straight line or by alternately arranging a PBS prism and a total reflection prism on a straight line. It is twice as large as the constituent cylindrical lens. Each PBS prism has a PBS film 14a that transmits P-polarized light and reflects S-polarized light. In addition, PBS array 1
Numeral 4 is arranged so that the central portion of the portion not shielded by the light shielding plate array 13 faces the central portion of each cylindrical lens of the cylindrical lens array 6b.

The light-shielding plate array 13 is a strip-shaped plate for preventing flare light from entering other than the desired opening of the PBS array 14.

The half-wave plate array 15 is a PBS array 14
Are arranged so as to cover every other emission port.

As shown in the modification of FIG. 7, the polarization converter 12 does not use the half-wave plate array 15 but has a structure in which every other half-wave plate 15a is arranged between the PBS prisms. Is also good.

In this configuration, when illumination light (P-polarized light component + S-polarized light component) generated by the illumination light generator 2 and having a random polarization direction reaches the polarization converter 12 shown in FIG. Is P from the opening of the light shielding plate array 13
The light enters the BS array 14, is separated into P-polarized light and S-polarized light by the PBS film 14a, and the P-polarized light travels straight as it is and is emitted through the opening of the half-wave plate array 15. On the other hand, the S-polarized light is reflected at 90 ° by the PBS film 14a, and is further reflected by the PBS film 1 of the adjacent PBS prism.
The light is again reflected by 90 ° at 4a, and exits through the half-wave plate 15a of the half-wave plate array 15. When passing through the half-wave plate 15a of the half-wave plate array 15, the S-polarized light component is rotated by 90 °, converted into P-polarized light, and emitted as P-polarized light. That is, the illumination light whose polarization direction is random is adjusted to the P-polarized light by the polarization converter 12.

Illumination light having a random polarization direction (P-polarized light +
When the (S-polarized light) reaches the polarization converter 12 shown in FIG. 7, the polarized light is separated and converted in the same manner, and emitted in the same manner as the P-polarized light.

Thus, according to the present embodiment,
The liquid crystal panel 1 can be illuminated by using illumination light having polarized light.

According to the present embodiment, the cylindrical lens array 6a and the cylindrical lens array 6
b, a polarization converter 12 is disposed between the
2, only one direction (Y direction) by the cylindrical lens array 6b is narrowed, so that an increase in light energy due to light being condensed in the condensed portion can be suppressed. The load (stress) on the PBS film 14a can be reduced, the deterioration of the polarization converter 12 can be prevented, and the durability can be improved.

In the present embodiment, the change converter 12
In the above description, the case where the illumination light is aligned with the P-polarized light has been described as an example. However, the illumination light can be aligned with the S-polarized light by changing the position of the half-wave plate 15a.

Further, in the present embodiment using the polarization converter 12, the subsequent portions of the second lens array set 6 are
The structure can be changed to the same structure as the second embodiment shown in FIG.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
It will be described based on. The lighting device A4 of the present embodiment includes:
A polarization converter 16 is disposed immediately before the side facing the illumination light generation device 2 in the first lens array set 5, and a convex cylindrical lens 17 and a polarization converter 17 are provided between the illumination light generation device 2 and the polarization converter 16. A concave cylindrical lens 18 is arranged.

The polarization converter 16 includes two PBS prisms 19, reflection prisms 20 located on both sides of the PBS prism 19, and a half-wave plate 21.

The convex cylindrical lens 17 condenses the parallel light emitted from the window 10a of the illumination light generator 2 only in the X-axis direction, and passes the parallel light as it is in the Y-axis direction. The concave cylindrical lens 18 is disposed at a position where the light flux converged by the convex cylindrical lens 17 becomes approximately half, and returns the converged light flux to parallel light.

In such a configuration, in the present embodiment, the illumination light generated by the illumination light generator 2 is first converted into P-polarized light or S-polarized light, so that the polarization-converted polarized light is converted. The projection on the used liquid crystal panel 1 and the optimization of the projection range in the projection can be performed.

Then, the polarization converter 16 of the present embodiment
Is hardly affected by light energy that is increased by the illumination light being condensed by the first and second lens array sets 5 and 6, and the deterioration of the polarization converter 16 due to the influence of light energy can be reliably prevented.

In the present embodiment, one direction of the parallel light emitted from the window 10a of the illumination light generator 2 is condensed by the convex cylindrical lens 17, and then converted into the parallel light by the concave cylindrical lens 18. Since the illumination light is returned, the illumination light emitted from the illumination light
6 and the illumination light can be effectively used. Further, the size of the polarization converter 16 and the integrator optical system 3 can be reduced.

Here, X in each of the embodiments described above.
The relationship between the axis and the Y axis is determined for convenience, and even if the directions of the X axis and the Y axis are switched, the essence of the present invention is not changed.

In the first and second lens array sets 5 and 6, the respective cylindrical lens arrays 5a and 5a
Although the case where 5b (6a, 6b) is formed separately has been described as an example, the structure may be integrally formed.

[0064]

According to the illumination device of the first aspect of the present invention, as the first lens array and the second lens array constituting the so-called integrator optical system, the first lens array and the second lens array are arranged in a direction orthogonal to each other. By using the first lens array set and the second lens array set, the setting of the projection range of the illumination light on the illuminated object can be optimized according to the horizontal and vertical dimensions of the illuminated object, and this is wasteful. The illumination light can be reduced and the illumination light can be effectively used.

According to the second aspect of the present invention, in the lighting device according to the first aspect, the plurality of light beams divided by the first and second lens array sets are projected so as to be superimposed on the entire surface of the object to be illuminated. Since the superimposed lens that bends in the right and left directions has cylindrical surfaces corresponding to the X direction and the Y direction, the illumination light that has passed through the first and second lens array sets is bent by this lens, so that the illumination light that accompanies the bending is formed. Waste is less likely to occur, and the effective use of illumination light can be further achieved.

According to the third aspect of the present invention, in the illuminating device according to the first or second aspect, the superimposing lens is disposed close to the side of the second lens array set facing the object to be illuminated. Before the illuminating light passing through the second lens array set spreads, the illuminating light can be bent by the superimposing lens and projected onto the illuminated object, and the optical path width between the second lens array set and the illuminated object can be suppressed. Therefore, when optical elements are interposed in the optical path, those optical elements can be made smaller, and the occurrence of illuminance unevenness on the illuminated object can be suppressed.

According to the fourth aspect of the present invention, in the lighting device according to the first or second aspect, since the superimposing lens is disposed at a substantially intermediate position between the second lens array set and the illuminated body, The illumination light that is bent by the lens and projected onto the illuminated object can be converted into substantially parallel light for each of the light beams divided by the first lens array set and the second lens array set. The illumination light can be projected onto the illuminated object without providing a condenser lens or the like for narrowing the illumination light at the position immediately before.

According to a fifth aspect of the present invention, in the illumination device according to any one of the first to fourth aspects, the polarization converter is disposed between the two cylindrical lens arrays in the second lens array set. Therefore, since only one cylindrical lens array can be focused near the polarization converter, the influence of the light energy, which becomes higher when the illumination light is focused on the focal point, becomes smaller, and the polarization conversion due to the influence of the light energy becomes smaller. The deterioration of the container can be prevented.

According to a sixth aspect of the present invention, in the illumination device according to any one of the first to fourth aspects, a polarization converter is disposed on a side of the first lens array set facing the illumination light generation device. Therefore, in carrying out any one of the first to fourth aspects of the present invention, it is possible to use either the P-polarized light component or the S-polarized light component obtained by performing the polarization conversion with the polarization converter. In addition, the influence of the light energy, which is increased by the illumination light being condensed by the first and second lens array sets, does not reach the polarization converter, and the deterioration of the polarization converter due to the influence of the light energy can be prevented.

According to the seventh aspect of the present invention, in the illumination device according to the sixth aspect, the convex cylindrical lens and the concave cylindrical lens are disposed between the illumination light generating device and the polarization converter. Therefore, by using the convex cylindrical lens and the concave cylindrical lens, the illumination light generated by the illumination light generator can be efficiently taken into the polarization converter, and the illumination light can be effectively used.

According to the illuminating device according to the eighth aspect, in the illuminating device according to any one of the first to seventh aspects, the illuminating light generating device includes a light-emitting lamp and a reflection light disposed to surround the light-emitting lamp. Since it has a mirror and a plane mirror having a window for allowing the light reflected by the reflecting mirror to travel in the Z direction orthogonal to the X direction and the Y direction, the illumination light generated by the illumination light generation device is converted into parallel light. After the adjustment, the light can be taken into the first and second lens array sets, whereby the illumination light can be effectively used.

[Brief description of the drawings]

FIG. 1 is an optical system configuration diagram showing a lighting device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a correspondence between a first lens array set and a second lens array set.

FIG. 3 is a graph illustrating the illuminance distribution in the X-axis and Y-axis directions on a liquid crystal panel.

FIG. 4 is an optical system configuration diagram showing a lighting device according to a second embodiment of the present invention.

FIG. 5 is an optical system configuration diagram showing a lighting device according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing a structure of a polarization converter.

FIG. 7 is a sectional view showing a structure of a modification of the polarization converter.

FIG. 8 is an optical system configuration diagram showing a lighting device according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Illuminated object 2 Illumination light generator 5 First lens array set 5a, 5b Cylindrical lens array 6 Second lens array set 6a, 6b Cylindrical lens array 7 Superposition lens 8 Light emitting lamp 9 Reflecting mirror 10 Planar mirror 10a Window 12, 16 Polarization Transducer 17 Convex cylindrical lens 18 Concave cylindrical lens

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03B 15/02 G03B 15/02 QRSK (72) Inventor Tadashi Tadashi Nakamagome 1 Ota-ku, Tokyo 3rd-6th Ricoh Co., Ltd. F-term (reference) 2H052 BA01 BA02 BA06 BA14 2H091 FA07Z FA17Z FA26Z FA29Z FA41Z LA18 LA30

Claims (8)

[Claims] An illumination light generating device, a cylindrical lens array in which a plurality of cylindrical lenses are arranged in an X direction and arranged on an optical path on which an illumination light generated by the illumination light generating device is projected onto an object to be illuminated. A first lens array group in which a plurality of cylindrical lens arrays in which a plurality of cylindrical lenses are arranged in the Y direction orthogonal to the X direction are arranged in front and rear; and one of the first lens array groups in the cylindrical lens array A cylindrical lens array comprising a plurality of cylindrical lenses correspondingly disposed near the focal point; and a plurality of cylindrical lenses disposed near the focal point corresponding to the other cylindrical lens array of the first lens array set. Lens in which a cylindrical lens array made of A ray set, and a plurality of light beams generated by the first and second lens array sets, which are bent so as to be projected onto the entire surface of the illuminated body after passing through the second lens array set, respectively. And a lens. 2. The lighting device according to claim 1, wherein the superimposing lens has a cylindrical surface corresponding to an X direction and a Y direction. 3. The lighting device according to claim 1, wherein the superimposing lens is disposed close to a side of the second lens array set facing the object to be illuminated. 4. The lighting device according to claim 1, wherein the superimposing lens is disposed at a substantially intermediate position between the second lens array set and the illuminated object. 5. The lighting device according to claim 1, wherein a polarization converter is disposed between the two cylindrical lens arrays in the second lens array set. 6. The illumination device according to claim 1, wherein a polarization converter is disposed on a side of the first lens array set facing the illumination light generation device. 7. The illumination device according to claim 6, wherein a convex cylindrical lens and a concave cylindrical lens are arranged between the illumination light generator and the polarization converter. 8. The illumination light generator, comprising: a light-emitting lamp;
2. A reflecting mirror arranged to surround the light-emitting lamp, and a plane mirror having a window for transmitting light reflected by the reflecting mirror in a Z direction orthogonal to the X direction and the Y direction. 8. The lighting device according to any one of items 7 to 7.