JP2000206464A - Illumination device and projection display device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illuminating device capable of obtaining bright illumination light with a high illuminance ratio while maintaining parallelism of light rays incident on a surface to be illuminated by a relatively small optical system. A luminous flux from a lamp (1) is an elliptical reflector (2).
The light is condensed on the incident surface of the glass rod 3 and is integrated by internal reflection of the glass rod 3.
The illumination information on the exit surface of the glass rod 3
An image is formed on the liquid crystal panel 8 by this. A PBS polarization conversion array is arranged at the position of the tertiary light source image formed on the way, and the polarization axes of the illumination light are aligned.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device and a projection display device using the same, and more particularly, to a projection display device for enlarging and projecting an image of an electro-optical device using a liquid crystal.

[0002]

2. Description of the Related Art Recently, attention has been focused on this type of projection type display device (liquid crystal projector) using a liquid crystal, in which the brightness of a projected image and the illuminance ratio indicating its uniformity are improved. As a technology for simultaneously realizing these, a so-called integrator polarization conversion optical system that splits a light beam by a combination of a fly-eye lens and superimposes it on a liquid crystal panel and performs polarization separation and polarization conversion on the optical path has become mainstream. ing. Although this optical system is one solution that balances the two characteristics of brightness and illuminance ratio, the divergence angle of the incident light beam on the liquid crystal panel is widened, and on the other hand, an illumination system for reducing it is also desired. I have.

As a technique for improving the illuminance ratio while reducing the divergence angle of a light ray incident on a liquid crystal panel, Japanese Unexamined Patent Publication No.
An illumination system using a rod lens as disclosed in Japanese Patent No. 034 has been proposed. These are optical systems that superimpose a plurality of light source images on the exit end face of the rod lens and form illumination information on the exit end face on the liquid crystal panel. The angle can be reduced.

[0004]

The illumination system using the rod lens described above is an optical system aimed at reducing the divergence angle of an incident light beam by targeting a relatively small liquid crystal panel. An illumination system that maintains the original characteristics while using a conversion optical system has not been realized. Therefore, in an optical system in which parallelism of incident light is regarded as important, such as a single-panel projection display device using a microlens as described later, there is a trade-off between brightness and illuminance ratio.

[0005] The present invention is to solve the above problems,
The purpose is to use a relatively small optical system,
It is an object of the present invention to realize a lighting device capable of obtaining bright and high-illumination-ratio illumination light while maintaining the parallelism of light rays incident on a surface to be irradiated. Another object of the present invention is to realize a projection display device capable of projecting a bright image with a high illuminance ratio by using the illumination device.

[0006]

In order to solve the above-mentioned problems, an illuminating device according to the present invention comprises a light source means, a first light condensing means for condensing light from the light source means, A glass rod for entering the reflected light from the incident surface, internally reflecting the light, and emitting the light to the emission surface; second focusing means for focusing the light flux emitted from the glass rod on the surface to be irradiated; And a light beam emitted from the glass rod are separated into two linearly polarized light beams having polarization axes substantially orthogonal to each other, and one light beam is converted into a linearly polarized light axis of the other light beam. Polarization conversion means.

[0007] Further, a light source means, a first condensing means for condensing light from the light source means to form a primary light source image, and a light flux from the primary light source image into a plurality of light fluxes by internal reflection. A light beam splitting means for splitting and emitting a plurality of secondary light source images to form a plurality of secondary light source images; a second light condensing means for forming illumination information on an emission surface of the light beam splitting means on a surface to be irradiated; The light beam emitted from the light beam splitting unit is separated between the light beam splitting unit and two linearly polarized light beams whose polarization axes are substantially orthogonal to each other, and one light beam is converted to the linear polarization axis of the other light beam. Polarization conversion means.

According to the above two aspects of the invention, the light beam from the light source is superimposed (integrated) so as not to be diffused by the glass rod or the light beam splitter and emitted, and the polarization axes are aligned by the polarization converter. Since the irradiation surface is configured to be illuminated, the light use efficiency with respect to the illumination of the irradiation surface can be improved, and the uneven brightness on the irradiation surface can be reduced. In addition, since the light that is superimposed on the light exit surface is emitted by reducing the light diffusion by a glass rod (light beam splitting means) using internal reflection, the spread of the light beam is small and the parallelism is relatively small with respect to a small irradiation surface. High illumination can be performed.

In the above two illuminating devices of the present invention, the second condensing means emits light from the glass rod (light beam splitting means) between the glass rod (light beam splitting means) and the surface to be irradiated. The plurality of light fluxes are condensed to form a plurality of light source images (tertiary light source images), and the polarization conversion means is arranged near a position where the plurality of light source images (tertiary light source images) are formed. Features.

According to the structure of the present invention, since the polarization conversion is performed at the position of the light source image formed to be reduced to a small area,
The size of the polarization conversion means can be reduced, and the parallelism of the incident light beam with respect to the small irradiation surface can be increased.

In the illumination device according to the above two inventions, the polarization conversion means separates the light beam emitted from the glass rod (light beam splitting device) into two linearly polarized light beams whose polarization axes are substantially orthogonal to each other and has different directions. A plurality of polarized light separating means, a plurality of reflecting means for aligning one of the separated light beams in the traveling direction of the other light beam, and converting the one separated light beam into a linear polarization axis of the other light beam. And a plurality of polarization axis rotating means.

According to the structure of the present invention, since the polarization conversion can be performed at each position where a plurality of light source images are formed, the polarization conversion can be surely performed by the small polarization conversion means.

In the illuminating device according to the above two inventions, the polarized light separating means reflects the light source images, which are centered in the direction in which the polarized light separation is performed among the plurality of light source images, in two directions apart from each other. It is characterized by including a configuration.

According to the configuration of the present invention, since the reflected light of the light source image centered in the polarization separation direction is divided into two and is incident on the reflection means, the polarization separation means and the reflection means can be reduced in size. . Therefore, even if the gap between the adjacent light source images is small, the polarization conversion can be performed, and the efficiency of the polarization conversion can be increased. Further, it is possible to achieve a high luminance by using a high-output light source having a large arc size and a high illuminance ratio by using a glass rod (a light beam dividing means) having a small cross-sectional area.

In the illumination device according to the present invention, the size of the reflection surface of the polarization separation means and the reflection means for the light source image serving as the center is larger than that of the polarization separation means and the reflection means for the light source image other than the center. It is characterized by being smaller than the size of the surface.

According to the configuration of the present invention, since the size of each reflecting surface can be adjusted to the size of the light source image incident thereon, the polarization conversion can be performed efficiently. Further, the number of the polarization separating means and the reflecting means constituting the polarization converting means can be reduced, and the polarization converting means can be simplified.

Alternatively, in the lighting device of the invention described above,
The size of the reflection surface of the polarization separation means and the reflection means for the light source image serving as the center is equal to the size of the reflection surface of the polarization separation means and the reflection means for the light source image other than the center.

According to the structure of the present invention, the size of all the reflecting surfaces is made uniform, so that the thickness of the polarization conversion means can be reduced.

In the illumination device according to the invention, the polarized light separating means is configured such that all of the reflection directions of the plurality of polarized light separating means are the same.

According to the structure of the present invention, since the directions of all the reflecting surfaces can be made uniform, it is possible to easily manufacture such that all the elements are cut after the lamination is formed.

In the illumination device of the above two inventions, the polarization conversion means further comprises a deflection means for changing a traveling direction of the emitted light, on an emission surface of the light beam reflected and emitted by the reflection means.

According to the structure of the present invention, since the light beam deviated from the original optical path can be deflected by the polarization separating means and the reflecting means and made incident on the surface to be irradiated, the efficiency of incidence on the surface to be irradiated can be improved. it can.

The illuminating device according to the present invention is characterized in that the illuminating device further comprises an opening means for restricting incident light on an incident surface of the glass rod (light beam splitting means).

According to the structure of the present invention, by limiting the size of the light source image (primary light source image) formed on the entrance surface of the glass rod (light beam splitting means), the position of the position where the polarization conversion means is arranged can be determined. Since the light source image (tertiary light source image) can be reduced in size, it is possible to prevent unnecessary light from entering the polarization converter and to reduce the size of the polarization converter.

Further, the aperture means has an aperture for restricting incident light in the polarization separation direction of the polarization conversion means.

According to the structure of the present invention, while the light beam in the direction orthogonal to the polarization separation direction is efficiently incident on the polarization conversion means, the space for separating the light source image only in the polarization separation direction necessary for the polarization conversion. Can be secured.

[0027] In the illumination device of the above two inventions, it is characterized in that the illumination device further comprises a light shielding means which is arranged on the incident side of the polarization conversion means and shields a part of the light incident on the polarization conversion means.

According to the structure of the present invention, the entrance of a light beam different from the polarized light beam after the polarization conversion can be reduced, so that the degree of polarization after the polarization conversion is improved. Therefore, if this is used for a liquid crystal projector, the contrast of the projected image can be increased.

In the illumination device according to the above two inventions, the polarization rotating means is a half-wave plate.

According to the structure of the present invention, reliable polarization conversion is possible with a thin half-wave plate, and the degree of freedom in shape is high. Can also be arranged.

Further, a projection type display apparatus according to the present invention includes the above-described illumination device, a spectral unit for separating a light beam from the illumination device into a plurality of primary color lights, and an electric device for modulating the light beam from the spectral unit. It is characterized by comprising an optical device and projection means for projecting light modulated by the electro-optical device.

According to the configuration of the present invention, a bright projected image having a high illuminance ratio can be obtained by using illumination light having relatively high parallelism and a high illuminance ratio. Further, for example, a single-panel projection display device that requires parallelism in illumination light can be realized with high luminance and high illuminance ratio.

Further, in the projection display apparatus according to the present invention, the spectroscopic means is arranged between the polarization conversion means and the electro-optical device.

According to the configuration of the present invention, since the integrated (superimposed) polarized and converted illumination light is spectrally separated, it is reliably separated into primary color light and the subsequent spectral disturbance is small. Further, since the optical path of the optical system can be bent between the polarization conversion means and the electro-optical device, the size of the optical system can be reduced.

[0035]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of the present invention will be described in more detail.

(First Embodiment of Illumination Apparatus) FIG. 1 is a view showing a first embodiment of an illumination apparatus according to the present invention.

The illuminating device according to the present embodiment has a lamp 1 as a light source and an elliptical reflector 2 as a first condenser.
A glass rod 3 serving as a light beam splitting means, a first light collecting lens 4, a second light collecting lens 5 and a third light collecting lens 6 constituting a second light collecting means, and a polarization conversion means. Illuminates a liquid crystal panel 8 having a surface to be illuminated. In the present embodiment, a liquid crystal panel is taken as an example of an electro-optical device having a surface to be irradiated.

The lamp 1 is arranged near the first focal point of the elliptical reflector 2, and the light beam emitted from the lamp 1 is reflected by the elliptical reflector 2 and condensed near the second focal point of the elliptical reflector 2. A primary light source image G1 is formed such that an image of the light source lamp is formed on the incident surface. Note that the elliptical reflector 2 may be a parabolic reflector, in which case a condensing beam for converging a parallel light beam emitted from the parabolic reflector toward the incident surface of the glass rod 3 before the glass rod 3. What is necessary is just to provide a lens further.

The glass rod 3 is a columnar glass solid rod. The light beam incident on the glass rod 3 repeats internal reflection in the glass rod 3 to form a plurality of secondary light source images G21, G22, G23,... (See FIG. 2).

FIG. 2 is an explanatory diagram of the light beam splitting action by the glass rod 3. The cross-sectional shape of the glass rod 3 is shown in FIG.
As shown in (b), it is a quadrangle of horizontal a and vertical b, and the reflecting surfaces (inner surfaces) facing each other are parallel. That is, in the figure, the two reflecting surfaces in the vertical direction are parallel to each other, and the two reflecting surfaces in the horizontal direction are parallel to each other. Also,
The ratio of a to b is substantially equal to the ratio of the shape of the pixel area (display area) of the liquid crystal panel 8 as the surface to be irradiated, and they are similar. The length of the glass rod 3 is the secondary light source image G21, G
, G23,... Are set to pass through the center of the emission surface of the glass rod. At this time, this cross-sectional shape is sufficiently larger than the spread E of the luminous flux (FIG. 2A) that can be generated when the incident luminous flux condensed by the elliptical reflector 2 on the incident surface of the glass rod 3 is absent. , A part of the light beam is reflected on the inner surface of the glass rod 3 and becomes a virtual image of the primary light source image G1.
21, G22, G23,... The illustrated primary light source image is G1, which is also a secondary light source image G21 that is a virtual image of a light component emitted to the emission surface without reflection on the inner surface of the glass rod 3. Also, the secondary light source image G22
Is a virtual image of a light component reflected twice on the inner surface of the glass rod and emitted to the emission surface, and is a light component emitted obliquely on the emission surface, so that the virtual image is located in an oblique direction deviating from G21. . The secondary light source image G23 is a virtual image of a light component reflected three times on the inner surface of the glass rod and emitted to the emission surface, and is a light component emitted obliquely to the emission surface. A virtual image is located in a deviated oblique direction. In this manner, a secondary light source image is formed for each internal reflection number, and a plurality of secondary light source images G21, G22, G23,.
Is superimposed on the exit surface of the glass rod 3 and the light exit direction from the inside of the glass rod 3 with respect to the exit surface also becomes light superimposed from various directions. Is formed, and illumination information with an increased illuminance ratio is formed. The light beam emitted to the exit surface of the glass rod 3 is condensed by a condenser lens 4 and a condenser lens 5 as shown in FIG. 3, and corresponds to the secondary light source images G21, G22, G23,. 3
Next light source images G31, G32, G33,... Are formed. Since the light flux entering the glass rod 3 and internally reflected at different times is superimposed on the light exit surface at different angles, the condenser lens 4 is disposed on the light exit surface of the glass rod 3 so that the light beam exits from the light exit surface. The emission direction is regulated so as not to diffuse the emitted light, and the light is collected. The condenser lens 4 is preferably arranged so as to be bonded to the exit surface of the glass rod 3 by bonding. The condensing lens 5 is a lens for condensing light beams having different emission angles, the emission directions of which are regulated by the condensing lens 4, on a predetermined irradiated surface.

The condensing lens 5 is also an imaging lens that condenses the illumination information on the exit surface of the glass rod 3 on the liquid crystal panel 8, condenses the light superimposed on the exit surface, and emits it. Focusing is performed so as to irradiate a pixel region of the liquid crystal panel 8 having a shape similar to the surface. Therefore, once the tertiary light source image G3
The light beams converged as 1, G32, G33,... Are deflected by the condenser lens 6 so as to approach in a direction parallel to a normal defined on the pixel area of the liquid crystal panel 8 and are irradiated surfaces. The light is applied to the liquid crystal panel 8. Here, the condenser lens 6 does not have to be provided because it is a lens for adjusting the light beam direction.

Further, instead of a glass rod, other light splitting means having a structure capable of splitting and superimposing incident light and emitting the light as a light beam having a shape similar to the surface to be irradiated may be used.

As described above, according to the configuration of the present invention, the light beam from the light source means is superimposed (integrated) so as not to be diffused by the glass rod or the light beam dividing means.
And irradiates the surface to be illuminated in a state where the polarization axes are aligned by the polarization conversion means, so that the light use efficiency with respect to the illumination of the illuminated surface can be improved, and the luminance unevenness on the illuminated surface can be reduced. be able to. In addition, since the light that is superimposed on the light exit surface is emitted by reducing the light diffusion by a glass rod (light beam splitting means) using internal reflection, the spread of the light beam is small and the parallelism is relatively small with respect to a small irradiation surface. High illumination can be performed.

FIG. 4 shows tertiary light source images G31, G32, G3.
It is a figure for demonstrating the condensing state of 3, ..., and has shown the mode seen from the optical axis direction. Tertiary light source images G31, G3
The size, number, and interval of 2, G33,... Are the primary light source images G1.
, The incident angle, the cross-sectional shape of the glass rod 3, the length, and the like. In particular, the size of the tertiary light source image depends on the size of the primary light source image, and the interval between the light source images depends on the cross-sectional shape of the glass rod 3. If the cross-sectional shape is rectangular, the light source image in the long side direction is obtained. Are larger than in the short side direction. FIG.
, G31 is a light beam 3 including light that is not internally reflected and emitted with the center of the emission surface of the glass rod 3 as the optical axis.
Since the light source image is a three-dimensional light source image, three-dimensional light source images G32 of the light beam emitted from the glass rod 3 including the light internally reflected twice around the optical axis of the light beam as a whole are scattered in eight directions. And located. Although not shown, the light flux 3 including the light internally reflected three times by the glass rod 3 outside the G32
The three-dimensional light source images are scattered radially from G31.

For example, in the present embodiment, the liquid crystal panel 8
A rectangle having a long side in the y-axis direction (horizontal direction) in FIG.
Therefore, the cross section of the glass rod 3 having a similar shape is also a rectangle having a long side in the y-axis direction, and the interval y1 in the Y-axis direction of the light source image is larger than the interval z1 in the z-axis direction orthogonal to the Y-axis. Further, according to the study by the present applicant, a light source image may be formed around the nine light source images as shown in FIG.
It was found that the light energy was concentrated most on the central light source image G31, and that the energy was concentrated on the nine light source images shown here, including that. Therefore, the nine light source images may be subjected to polarization separation and polarization conversion using the relatively large gap between the light source images in the y-axis direction.

FIG. 5 shows an embodiment of the PBS polarization conversion array 7 arranged on the exit side of the condenser lens 5, and its XY
It is sectional drawing. The PBS polarization conversion array 7 is a polarization separation unit that separates an incident light beam into two linearly polarized light beams of P-polarized light and S-polarized light whose polarization axes are substantially orthogonal to each other and emits them in directions different from each other (for example, directions substantially orthogonal to each other). And one polarized light (S-polarized light) reflected by each polarized light separating film 9 and the other polarized light (S polarized light) transmitted through the polarized light separating film 9 (9a, 9b, 9c, 9d). The reflection film 10 (10a, 10b, 10c, 10d), which is a reflection unit for aligning the light beam with the P-polarized light, and the polarization axis of one of the incident polarized light (S-polarized light) is rotated to rotate the other polarized light (S-polarized light). A half-wave plate 11 (11a, 11b, 11c, 11) serving as a polarization axis rotating means for adjusting to a P-polarized light beam.
d) and a light-shielding plate 12 (1), which is a light-shielding means for shielding a light beam incident on the reflection film 10 without passing through the polarization separation film 9.
2a, 12b, 12c, 12d) and a plurality of columnar prisms 13 forming an array by filling the gaps therebetween. Each polarization separation film 9 and reflection film 10 are formed on the slope of any one of the prisms, and are bonded to the slope of the opposing prism via the film by adhesion. However,
The polarization separation films 9a and 9c and the reflection films 10a and 10c are formed in the middle of the slope of the prism 13 and are bonded to the slope of the opposing prism 13. Note that the half-wave plate 11 and the light shielding plate 12 are arranged on the incident surface of the prism 13.

In the PBS polarization conversion array 7 configured as described above, the luminous fluxes of the tertiary light source images G31 and G32 condensed by the condensing lens 5 are formed in the vicinity of the incident surface thereof. The three-dimensional light source image is arranged in the optical path of the three-dimensional light source image light beam so that, for example, the P-polarized light beam of the light beam (light beam of the three-dimensional light source image G31) incident on the polarization separation film 9a is transmitted and reflected as the light beam P1. The S-polarized light beam thus reflected is further reflected by the reflection film 10a, the traveling direction thereof is aligned with the above-mentioned light beam P1, and the polarization plane thereof is rotated by approximately 90 ° by passing through the half-wave plate 11a, and is converted into a P-polarized light beam. And is emitted as a light flux P2. On the other hand, the size of each of the polarization separation film 9b and the reflection film 10b is twice the size of each of the polarization separation film 9a and the reflection film 10a.
b (a three-dimensional light source image G32 and G3
3, ... may be included. Similarly, in the same manner as described above, the directions are aligned by the reflection film 10b, the polarization is converted by the half-wave plate 11b, and the light is aligned as P-polarized light, and emitted as light P3 and P4. Hereinafter, the polarization separation film 9c, the reflection film 10c,
The polarization conversion by the half-wave plate 11c, the polarization separation film 9d,
The polarization conversion by the reflection film 10d and the half-wave plate 11d is as follows.
9a, 10a, 1 symmetrical with respect to the optical axis (dashed-dotted line in the figure)
Similarly to the polarization conversion by 1a and the polarization conversion by 9b, 10b, and 11b, the incident light beam is separated into two polarized light beams that are substantially orthogonal to each other, and one polarized light is aligned with the other polarized light and emitted in the same direction. The polarization separation films 9a and 9c divide the light beam of the three-dimensional light source image G31 into two in the Y-axis direction and emit the light beams in different optical paths.

The above-mentioned P-polarized light and S-polarized light may be interchanged.

Further, as described above, the polarization axis rotating means is used as one.
The use of the half-wave plate 11 is effective in performing reliable polarization conversion by a simple method. In addition, since the wave plate has a high degree of freedom in shape, it is not limited to the above-described conversion of S-polarized light, and is arranged on the exit surface of the P-polarized light beam to convert P-polarized light to S-polarized light.
It is also possible to emit the light in the same polarization. The light-shielding plate 12 reduces the penetration of a light beam different from the polarized light beam after the polarization conversion, in this embodiment, the light beam which becomes the S-polarized light beam after the polarization conversion, thereby improving the degree of polarization after the polarization conversion. Can be.

Therefore, if the illumination device for irradiating the liquid crystal panel in the present embodiment is used for a projection type display device such as a liquid crystal projector, the light to the surface to be illuminated by the illumination device is divided so as not to diffuse the light source light, and Since the polarization axes of light incident on the liquid crystal panel after being subjected to polarization conversion after being superimposed are aligned, the light use efficiency of the light source light can be increased, and the contrast of the projected image can be increased.

As described above, since the polarization conversion is performed at the position of the light source image formed by being reduced to a small area by the first and second condenser lenses, it is possible to reduce the size of the polarization conversion means and to reduce the size of the irradiated object. The parallelism of the incident light with respect to the surface can be increased. In addition, since the polarization conversion can be performed by the reflection surface corresponding to the size of each light source image at each position where a plurality of light source images are formed, the polarization conversion can be reliably performed by the small polarization conversion unit. it can.

As described above, there are three light source images in which the energy is concentrated in the polarization separation direction, and the light source image at the center thereof is polarization-converted so as to be separated into two on both sides.
Since the light source images at both ends are polarized and converted so as to further expand to the outside, the polarization separation films 9a and 9c as polarization separation means and the reflection films 10a and 10c as reflection means are provided.
Can be reduced in size. Therefore, even if the gap between the adjacent light source images is small, the polarization conversion can be performed, and the polarization conversion efficiency can be increased. Furthermore, since the light source image can be separated and the polarization converted with a small area, high brightness can be achieved by using a high power light source with a large arc size, and high illuminance ratio can be achieved by using a glass rod (light beam splitting means) with a small cross section. Becomes In addition,
As described above, since most of the energy is concentrated on the nine light source images, the polarization separation films 9b and 9d and the reflection films 10b and 10d have the sizes of the respective reflection films for the purpose of relieving the light source images on the outside. Because there is no need to limit
The polarization conversion efficiency at that portion can also be increased.

The liquid crystal panel 8 is an example of an electro-optical device. When a liquid crystal requiring a polarizing plate such as a twisted nematic type, a horizontal alignment type, a vertical alignment type, or a ferroelectric type is used, a pair of unillustrated polarizing plates is used. The liquid crystal panel 8 is interposed between the plates. In the case of a light scattering type liquid crystal such as a polymer dispersion type, only a liquid crystal panel is arranged without using a polarizing plate. In the liquid crystal panel 8, a plurality of pixels are arranged in a matrix, and a voltage corresponding to display information of each pixel is applied to the liquid crystal which is an electro-optical device for each pixel, and the amount of emitted light is varied for each pixel. Then, the incident light is modulated. LCD panel 8
Is a transmissive liquid crystal panel, light is emitted from the side opposite to the incident side, and an image is displayed by the modulated light.
As described above, since the cross-sectional shape of the glass rod 3 is similar to the pixel region of the liquid crystal panel 8, the cross-sectional shape of the light beam at the exit surface is also similar to the pixel region.
When the light irradiated by the condenser lens 5 is irradiated so as to substantially coincide with or include the image area of the liquid crystal panel 8, the light use efficiency can be increased.

As described above, according to the present embodiment, since integration is performed by utilizing the internal reflection of the glass rod 3, the spread of the luminous flux is small, so that it can be applied to an electro-optical device such as a small liquid crystal panel. Illumination with relatively high parallelism can be performed with high efficiency and a high illuminance ratio.

(Second Embodiment of Illumination Apparatus) FIG. 6 is a view showing a polarization conversion means in a second embodiment of the illumination apparatus of the present invention.

In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and the description is omitted.

The PBS polarization conversion array 7 in this embodiment separates an incident light beam into two linearly polarized light beams (P-polarized light and S-polarized light) whose polarization axes are substantially orthogonal to each other, and separates the light beams into mutually different directions (for example, directions substantially orthogonal to each other). Polarization separation film 14 (14a, 14b, 14) as polarization separation means for emitting light to
c, 14d, 14e, and 14f) and the other polarized light (S-polarized light) reflected by each polarization splitting film 14 or one polarized light (P
The reflection film 15 (15a), which is a reflection means for reflecting one polarized (P-polarized) light beam or another reflected (S-polarized) polarized light beam that reflects a (polarized) light beam and transmitted through the polarization separation film 14, , 15b, 15c, 15d, 15e, 1
5f) and a half-wave plate 16 (16a, 16a) serving as a polarization axis rotating means for rotating the polarization axis of the other polarized (S-polarized) light beam to be adjusted to one polarized (P-polarized) light beam.
b, 16c, 16d) and PB without passing through the original optical path
A light shielding plate 17 (17a, 17b, 17c, 17) serving as a light shielding unit for shielding a light beam emitted from the S-polarization conversion array.
d) and a plurality of prisms 18 that fill the gaps to form an array. The difference from the PBS polarization conversion array in the first embodiment is that all the polarization separation films 14 and the reflection films 15 have the same size. Further, the light shielding plate 17 exists not only on the plane of incidence on the reflection film 15 but also on the planes of incidence on the specific polarization separation films 14c and 14f. Further, the 波長 wavelength plate 16 is not only present on either one of the exit surfaces of the polarization splitting film 14 or the reflection film 15, but is arranged on both specific exit surfaces. Note that, similarly to the PBS polarization conversion array in the first embodiment, the polarization separation film 14 and the reflection film 15 are formed on the slope of any one of the prisms and bonded to the slope of the opposing prism via the film by bonding. Is done.

In the PBS polarization conversion array configured as described above, the tertiary light source images G31 and G32 condensed by the condensing lenses 4 and 5 are formed in the vicinity of the incident surface, and the polarization separation films 14a and 14b are formed. , 14d, 14e and the reflecting films 15b, 15e.
For example, a light beam (a light beam of the three-dimensional light source image G31) that is disposed in the light path of the G32 light beam and is incident on the polarization separation film 14a, for example.
Of the above, the P-polarized light flux is transmitted as the light flux P1, and the reflected S-polarized light flux is further reflected by the reflection film 15a, the traveling direction is aligned with the above-described light flux P1, and is transmitted through the half-wave plate 16a. The polarization plane is rotated by about 90 °, converted into a P-polarized light beam, and emitted as a light beam P2. The light beam (the light beam of the three-dimensional light source image G32) incident on the polarization separation film 14b is similarly emitted as light beams P3 and P4. However, the light beam directly incident on the reflection film 15b (the three-dimensional light source image G32
The light beam reflected by the reflection film 15b is separated into a P-polarized light beam and an S-polarized light beam by the polarization splitting film 14c, and the reflected S-polarized light beam is polarized by the half-wave plate 16b. Is rotated by 90 °, is converted into a P-polarized light beam, and is emitted as a light beam P5.
The P-polarized light beam that has passed through c is reflected by the reflection film 15c, is aligned with the light beam P5, and is emitted as a light beam P6.

Further, the polarization separation film 14d, the reflection film 15d,
Polarization conversion by the half-wave plate 16c and the polarization separation film 14
e, reflection film 15e, polarization conversion by half-wave plate 16d, reflection film 15e, polarization separation film 14f, half-wave plate 1
6d and the polarization conversion by the reflection plate 15f are the same as the above-described polarization conversion at a position symmetrical with respect to the optical axis. Thus, as a result, all the emitted light beams are aligned with the P-polarized light beam.

As is clear from the above description and FIG. 6, according to the present embodiment, by making the sizes of all the reflecting surfaces uniform, the thickness of the polarization conversion means can be reduced. In addition, since the size of each reflection film is uniform, it is easy to manufacture the PBS polarization conversion array. Note that the light shielding plate 17 is
a, 17d, light-shielding plates 17a, 17 for preventing unnecessary light from entering
c, the polarization separation films 14c and 14f, and the reflection films 15c and 15
It is composed of light shielding plates 17b and 17d for preventing unnecessary light from entering f. Further, the half-wave plate 16 is not limited to the position described in the present embodiment, and may be arranged so that all outgoing lights are aligned with the S-polarized light beam.

Further, a configuration in which the P-polarized light and the S-polarized light are exchanged may be adopted.

(Third Embodiment of Illumination Apparatus) FIG. 7 is a view showing polarization conversion means in a third embodiment of the illumination apparatus according to the present invention.

In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and the description is omitted.

The PBS polarization conversion array 7 in the present embodiment converts the light flux condensed by the condenser lenses 4 and 5 into two linearly polarized light beams (P-polarized light,
(S-polarized) polarized light separating films 19 (19a, 19b, 19c), which are polarized light separating means for separating the light beams and emitting the light beams in directions different from each other (for example, directions substantially orthogonal to each other), and reflected by the respective polarized light separating films 19. A reflection film 20 (20a, 20b, 20c) which is a reflection means for reflecting the other polarized (S-polarized) light beam and aligning it with the traveling direction of the one polarized (P-polarized) light beam transmitted through the polarization separating film 19; A half-wave plate 21 (21a, 21b, 21c), which is a polarization axis rotating means for rotating the polarization axis of the other polarized (S-polarized) light beam to match the one polarized (P-polarized) light beam;
A light-shielding plate 22 (22a, 22a, which is a light-shielding unit for shielding a light beam incident on the reflection film 20 without passing through the polarization separation film 19).
22b, 22c) and a plurality of prisms 23 which form an array by filling the gap therebetween. The difference from the PBS polarization conversion arrays in the first and second embodiments is that all the polarization separation films 19 and the reflection films 20 have the same size and the same reflection direction. The first
Similarly to the PBS polarization conversion array according to the second embodiment, the polarization separation film 19 and the reflection film 20 are formed on the slope of any one of the prisms and bonded to the slope of the opposing prism via the film by adhesion. You.

In the PBS polarization conversion array configured as described above, the tertiary light source image is formed near the incident surface thereof,
3 so that the light enters the polarization separation films 19a, 19b, and 19c.
For example, a P-polarized light beam among the light beams incident on the polarization separation film 19a is disposed in the optical path of the light beam of the two-dimensional light source image.
The S-polarized light beam transmitted and reflected as 1 is reflected by the reflection film 20a.
Is further reflected by the light beam P1 so that the light beam P1 has the same traveling direction as the light beam P1.
Injected as 2. The same applies to the polarization separation films 19b and 19c.
b, the polarization conversion by the half-wave plate 21b and the polarization conversion by the polarization separation film 19c, the reflection film 20c, and the half-wave plate 21c are performed by the polarization separation film 19a, the reflection film 20a, and the half-wave plate 21a. It is performed in the same way as the conversion. As a result, all the emitted light beams are aligned with the P-polarized light beam.

As is apparent from the above description and FIG. 7, according to this embodiment, the arrangement and operation of the polarization conversion means are simplified by aligning the directions of all the reflecting surfaces. Therefore, the bulk member in which all the elements are stacked is 4
By cutting at an angle of 5 [deg.], A simple manufacturing such as manufacturing a PBS polarization conversion array becomes possible. The light shielding plate 22 is disposed at a position where unnecessary light is prevented from entering the reflection films 20a, 20b, and 20c. Also, a half-wave plate 2
Reference numeral 1 is not limited to the position described in the present embodiment, and may be arranged so that all outgoing lights are aligned with the S-polarized light beam.

Further, a configuration in which the P-polarized light and the S-polarized light are exchanged may be adopted.

(Fourth Embodiment of Illumination Apparatus) FIG. 8 is a view showing a polarization conversion means in a fourth embodiment of the illumination apparatus according to the present invention.

In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and the description is omitted.

In this embodiment, the PBS polarization conversion array 7 described in the first embodiment will be described as an example, but the present invention is also applicable to the PBS polarization conversion array 7 described in other embodiments. is there.

The difference between the PBS polarization conversion array 7 in the present embodiment and the PBS polarization conversion array in the above-described embodiment is as follows.
The half-wave plate 24 (24a, 24b, 24c) is arranged on the optical path of the P-polarized light beam transmitted through the polarization separation film 9,
A deflecting prism 25 serving as a deflecting means for deflecting a light beam deviated from an original light path toward a surface to be irradiated by a polarization separation film 9 and a reflection film 10 on an output light path of some S-polarized light beams.
(25a, 25b). That is, P
The BS polarization conversion array 7 is a condensing lens 5 for forming illumination information on the exit surface of the glass rod 3 on the liquid crystal panel 8.
Since the light beam reflected by the polarization separation film 9 is decentered in the distance spectral path between the polarization separation film 9 and the adjacent reflection film 10 and deviates from the original light path of the condenser lens 5. Become. Accordingly, by joining the deflecting prism 25 to at least the outermost outgoing surface of the light beam emitted from the PBS polarization conversion array 7, the eccentricity of the light emitted from the outgoing surface is corrected by the deflecting prism 25 as the deflecting means. That is.

The deflecting prisms 25a and 25b are prism 1
3 and a slope is formed in a direction in which the traveling direction of the light beam incident thereon is deflected so as to approach the liquid crystal panel 8. That is, the light flux reflected by the deflection separation film 9b and changed its path by the reflection film 10b passes through an optical path as indicated by a broken line 26 when there is no deflection prism 25a in the direction of the solid line 27 by the refraction of the deflection prism 25a. Is corrected. Therefore, according to the present embodiment, the direction of the light flux leaking to the outside of the liquid crystal panel 8 can be corrected and made incident on the liquid crystal panel 8, so that the efficiency of incidence on the liquid crystal panel 8 can be increased.

The configuration of the deflecting means is not limited to this embodiment. At least the angle of the reflection films 10b and 10d for reflecting the light beams emitted from the outermost side is changed to correct the direction of the light beams reflected there. The reflective film may also have the function of the deflecting prism 25 described in the present embodiment. Also, a deflection prism may be provided on the exit surfaces of the reflection films 10a and 10c. Further, in the present embodiment, the installation position of the half-wave plate 24 is set on the transmission optical path of the polarization separation film 9 in order to avoid lamination of the half-wave plates 24a and 24c and the deflection prisms 25a and 25b.
It may be on the reflected light path.

As described above, in the configuration of the present embodiment, the deflecting means is similarly arranged in the optical path of the light beam emitted from the outside in the PBS polarization conversion array 7 of the other embodiments as well as the first embodiment. Thus, the amount of light applied to the liquid crystal panel can be increased.

(Fifth Embodiment of Illumination Apparatus) FIG. 9 is a view showing a fifth embodiment of the illumination apparatus according to the present invention.

In the following description, the same components as those of the first embodiment are denoted by the same reference numerals, and the description is omitted.

The feature of this embodiment is that an aperture, which is an opening means for restricting incident light, is provided on the entrance surface of the glass rod (light beam splitting means) 3 in the first embodiment. FIG. 9A shows a circular aperture 28 having a circular opening, and FIG. 9B shows a rectangular aperture 29 having a rectangular opening. Light incident on the hatched diagrams in each figure is blocked by the aperture.

As described above, the provision of the aperture on the entrance surface of the glass rod 3 makes it possible to form the primary light source image G formed thereon.
This is equivalent to making 1 smaller. As described above, since the size of the secondary and tertiary light source images depends on the size of the primary light source image, according to the present embodiment, the PBS polarization conversion array 7 is used.
The size of each of the tertiary light source images at the position where is located can be reduced. Therefore, since the distance between the tertiary light source images (y1, z1 in FIG. 4) is widened, it is possible to reduce the entry of unnecessary light into the PBS polarization conversion array 7 and to eliminate the light shielding plate. In other words, if the interval between the light beams incident on the PBS polarization conversion array 7 is narrow, it is necessary to arrange a light-shielding plate on the incident surface so as to prevent light from being incident on the incident surface where polarization conversion is not possible, and light loss there occurs. If the interval between the light beams is widened, a certain amount of light can be separated by the light beams themselves, so that the light loss is reduced and, in some cases, a light-shielding plate becomes unnecessary.

In particular, according to the rectangular aperture 29 as shown in FIG. 9B, the aperture can be made to function as an aperture only in the Y-axis direction which requires a space for polarization conversion. The separation performance of the tertiary light source image can be improved while maintaining the transmission efficiency of the rectangular aperture 29.

(Embodiment of Projection Display Apparatus) FIG.
1 is a diagram illustrating an overall configuration of an embodiment of a projection display device using an illumination device according to the present invention. In the projection display device of the present embodiment, any one of the illumination devices of the above-described embodiments of the illumination device can be used.

As described above, in the illumination device of the present invention, the illumination information on the exit surface of the glass rod 3 (the light beam emitted along the shape of the exit surface) is similarly enlarged by the condenser lens 5 so that the liquid crystal panel 8 will be illuminated. Therefore, depending on the size of the liquid crystal panel 8 and the cross section of the glass rod 3, the PBS polarization conversion array 7 as the polarization conversion means and the liquid crystal panel 8 or the condenser lens 6 (the condenser lens 6 collimates the incident light and A space corresponding to the enlargement ratio is generated between the light beam and the panel 8). As a matter of course, as the distance increases, the conjugation ratio of the condenser lens 5 increases, so that the parallelism of the incident light on the liquid crystal panel 8 increases. In the present embodiment, the dichroic mirror 30, which is a spectral unit that splits the light from the light source into a plurality of color lights by using this space, is arranged.

The dichroic mirror 30 includes three dichroic mirrors, each of which is formed with a different wavelength selective reflection film for selectively reflecting or transmitting red light, green light, and blue light, and arranged at a predetermined angle to each other. Mirror 30
R, 30G, and 30B. For example, the dichroic mirror 30R is a mirror that reflects red light and transmits green light and blue light. Dichroic mirror 30G
Is a mirror for further separating the green light and the blue light transmitted through the dichroic mirror 30R, and reflects the green light and transmits the blue light. Dichroic mirror 30B
Is a mirror that reflects the blue light transmitted through the dichroic mirror 30G. Each dichroic mirror 30R,
30G and 30B are arranged at a predetermined angle to each other, and the reflected lights enter the liquid crystal panel 8 from different directions. In the present embodiment, the light passes through the condenser lens 6 before being incident on the liquid crystal panel 8 and undergoes the refraction action, but the separated state of the light beam is maintained. In addition, dichroic mirror 3
Reference numeral 0 denotes three dichroic mirrors, but the optically last mirror (30B) may be a total reflection mirror, and a spectral unit can be configured by using at least two dichroic mirrors. Further, a prism having a wavelength selective reflection film may be used instead of the dichroic mirror. In addition, the order of spectral separation of red light, green light, and blue light may be any.

FIG. 11 is a partial sectional view of the liquid crystal panel 8 in FIG. The liquid crystal panel 8 is an active matrix liquid crystal panel provided with a microlens array 33 for condensing each color light beam separated by the light separating means to a corresponding pixel, and a pair of polarizing plates (not shown) before and after them. Is arranged. The liquid crystal panel 8 has a twisted nematic (TN) liquid crystal 36 sealed between two transparent substrates 34 and 35 such as glass, and one substrate 34 has a common electrode 37 and a black matrix 38 for shielding unnecessary light. Are formed, and the other substrate 35 has the pixel electrode 3
9. Thin film transistor (TF) as switching element
T) 40 and the like are formed, and the pixel electrode 3
When a voltage is applied to the liquid crystal 9, the liquid crystal 36 sandwiched between the common electrode 37 and the common electrode 37 is driven. The other substrate 3
In FIG. 5, a plurality of scanning lines and a plurality of data lines are arranged so as to intersect with each other.
The source is connected to the data line, and the drain is connected to the pixel electrode 39. Then, the selection voltage is sequentially applied to the scanning lines, and the TFTs 40 of the horizontal pixels turned on in response to the selection voltage are applied.
The drive voltage of each pixel is written to the pixel electrode 39 via the. The TFT 40 is turned off by the application of the non-selection voltage, and holds the applied driving voltage in a storage capacitor (not shown). The pixel electrode 39 is arranged in a region corresponding to the opening of the liquid crystal panel (the opening of the black matrix 38).
Each pixel is constituted by T40 and the pixel electrode 39 (a storage capacitor connected to the pixel electrode as necessary). The liquid crystal 36 can be of various types such as a ferroelectric type, an antiferroelectric type, a horizontal alignment type, a vertical alignment type, and a polymer dispersion type, in addition to the TN.

The microlens array 33 formed on the glass plate by etching or the like and one of the substrates 34 are bonded to each other via a resin layer (adhesive) 41 having a low refractive index. The unit lenses (convex or concave portions of the lens) of the microlens array 33 have a pitch corresponding to three times the pixel pitch in the horizontal direction (scanning line direction) of the liquid crystal panel 8 and reflect the dichroic mirror 30 at different angles. The red light, green light, and blue light emitted at different angles enter each unit lens of the microlens array 33 at different angles, and the red light, green light, and blue light are respectively adjacent to each other in the horizontal direction by each unit lens. Light is condensed near the pixel electrodes 39 of three pixels corresponding to the lens. Each unit lens of the microlens array 33 has a focal length such that each color light is focused on the pixel electrodes of three adjacent pixels corresponding to this lens. In the figure, the green light G which is incident on the liquid crystal panel while proceeding substantially straight is condensed on the pixel electrode 39G by the unit lens of the microlens array 33 and emitted as it is. On the other hand, the red light R and the blue light B that are symmetrically incident on the green light G at an angle corresponding to the angle that the dichroic mirrors 30R and 30B have with respect to 30G are converted into pixel electrodes 39R by the unit lens.
And 39B, respectively, and emitted at an angle symmetric to the green light G. Note that, if the order of spectral separation in the dichroic mirror 30 is different, the incident position of color light on the liquid crystal panel 8 shown in FIG.

Each light beam condensed on the pixel electrode 39 of the liquid crystal panel 8 as described above undergoes modulation in accordance with the signal applied to the liquid crystal panel 8 and exits therefrom. Is enlarged and projected on the front screen 32. The three color lights modulated by the three adjacent pixels are projected so as to overlap at the same position on the screen 32 in the above process. In addition, this projection type display device is a rear type in which the screen 32 is projected from the back,
A front type that projects from the front may be used.

According to the present embodiment, a bright projected image with a high illuminance ratio can be obtained by using illumination light having a relatively high parallelism and a high illuminance ratio. In addition, a single-panel projection display device that requires high parallelism of illumination light as described in the present embodiment can be realized with a high luminance and a high illuminance ratio. At that time, the dichroic mirror 30 is
Since it is arranged between the S-polarized light conversion array 7 and the liquid crystal panel 8, the illumination light after the integration and the polarization conversion is reliably separated into the primary color light, and the subsequent disturbance of the spectrum is small. Further, since the optical path is bent by the dichroic mirror 30, the size of the optical system can be reduced as shown in FIG.

The present embodiment is not limited to a single-panel type projection display device, but a three-panel projection system using a liquid crystal panel serving as a modulating unit for each of the three color lights separated by the spectroscopic unit. It is also applicable to a type display device. Further, the liquid crystal panel is not limited to the transmission type, and may be a reflection type liquid crystal panel using pixel electrodes as reflection electrodes.

Further, as an electro-optical device for performing light modulation,
In a mirror device (for example, a digital mirror device (DMD) developed by Texas Instruments) which provides a reflection mirror for each pixel and switches and modulates the reflection angle of the reflection mirror according to an image signal. Also, the present invention can be applied to an illumination device that irradiates the device with light from a light source.

(Modifications) The present invention is not limited to the embodiments described above, and various modifications and changes can be made without departing from the spirit of the present invention.

For example, although the description has been made of the case where the green light pixel is arranged at the center of the microlens, the red light or blue light pixel may be arranged at the center.

Although the glass rod has been described as a solid glass rod, the rod is hollow (the outer frame is a reflecting surface composed of glass or the like and the center is a hollow prism. In this case, each reflecting surface reflects light). It can be a light pipe. In addition, a rod made of resin may be used instead of a rod made of glass.

The S-polarized light and P-polarized light described in each figure are
The reverse is also acceptable.

[0093]

As described in detail above, according to the illumination apparatus of the present invention, a relatively small optical system is used to maintain the parallelism of light rays incident on the surface to be illuminated while maintaining a high illumination ratio. You can get light. Further, by using the lighting device, a projection display device capable of projecting a bright image with a high illuminance ratio can be realized.

[Brief description of the drawings]

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

FIG. 2 is an explanatory diagram of luminous flux division by a glass rod of the lighting device according to the present invention.

FIG. 3 is an explanatory diagram of formation of a tertiary light source image by the illumination device according to the present invention.

FIG. 4 is a front view of a tertiary light source image by the illumination device according to the present invention.

FIG. 5 is a diagram showing polarization conversion means in the first embodiment of the illumination device according to the present invention.

FIG. 6 is a diagram showing polarization conversion means in a second embodiment of the illumination device according to the present invention.

FIG. 7 is a diagram showing polarization conversion means in a third embodiment of the lighting device according to the present invention.

FIG. 8 is a diagram showing polarization conversion means in a fourth embodiment of the illumination device according to the present invention.

FIG. 9 is a diagram showing a fifth embodiment of the lighting device according to the present invention.

FIG. 10 is a diagram showing an embodiment of a projection display device according to the present invention.

FIG. 11 is an explanatory diagram of a liquid crystal panel of the projection display device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lamp 2 Elliptical reflector 3 Glass rod 4 Condensing lens 5 Condensing lens 6 Condensing lens 7 PBS polarization conversion array 8 Liquid crystal panel 9 Polarization separation film 10 Reflection film 11 1/2 wavelength plate 12 Light shielding plate 13 Prism 28 Circular aperture 29 Rectangular aperture 30 Dichroic mirror 31 Projection lens 32 Screen

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H099 AA12 BA09 CA01 DA05 5C060 AA00 BA04 BB13 BC01 BD02 BE05 BE10 EA01 GA02 GB06 HC01 HC12 HC20 HD02

Claims (19)

[Claims] 1. A light source means, a first condensing means for condensing light from the light source means, and a glass rod for entering the condensed light from an incident surface, internally reflecting the light, and emitting the reflected light to an exit surface. A second light condensing means for condensing a light beam emitted from the glass rod to the surface to be irradiated; and a second light condensing means disposed between the glass rod and the surface to be irradiated, and emitted from the glass rod. An illumination device, comprising: a polarization conversion unit that separates a light beam into two linearly polarized light beams whose polarization axes are substantially orthogonal to each other and converts one of the light beams into a linearly polarized light axis of the other light beam. 2. The illumination device according to claim 1, wherein the second light condensing means condenses a light flux emitted from the glass rod between the glass rod and the surface to be irradiated. An illumination apparatus, wherein the light source image is formed, and the polarization conversion means is arranged near a position where the plurality of light source images are formed. 3. The illumination device according to claim 1, wherein the polarization conversion unit separates the light beam emitted from the glass rod into two linearly polarized light beams whose polarization axes are substantially orthogonal to each other and emits the light beams in different directions. A plurality of polarized light separating means, a plurality of reflecting means for aligning the separated one light beam in the traveling direction of the other light beam, and a plurality of polarization axes for converting the separated one light beam into a linear polarization axis of the other light beam. A lighting device, comprising: a rotating unit. 4. A light source means, a first light condensing means for condensing light from the light source means to form a primary light source image, and a light flux from the primary light source image is converted into a plurality of light fluxes by internal reflection. A light beam splitting means for splitting and emitting a plurality of secondary light source images to form a plurality of secondary light source images; a second light condensing means for forming illumination information on an emission surface of the light beam splitting means on a surface to be irradiated; The light beam emitted from the light beam splitting means is disposed between the light beam splitting means and two linearly polarized light beams whose polarization axes are substantially orthogonal to each other, and one light beam is converted into the linear polarization axis of the other light beam. An illumination device comprising: a polarization conversion unit. 5. The illumination device according to claim 4, wherein the second light condensing means condenses the plurality of secondary light source images between the light beam splitting means and the irradiation surface. And a third light source image is formed.
An illuminating device arranged near a position where a next light source image is formed. 6. The illumination device according to claim 4, wherein the polarization conversion unit separates the light beam emitted from the light beam splitting unit into two linearly polarized light beams whose polarization axes are substantially perpendicular to each other, and separates the light beams into directions different from each other. A plurality of polarized light separating means for emitting light, a plurality of reflecting means for aligning the separated one light beam in the traveling direction of the other light beam, and a plurality of converting the one separated light beam into a linear polarization axis of the other light beam And a polarization axis rotating means. 7. The illuminating device according to claim 3, wherein the polarization separation unit separates light source images that are centered in a direction in which the polarization separation is performed among the plurality of light source images. A lighting device comprising a configuration that reflects light in two directions. 8. The illuminating device according to claim 7, wherein the size of the polarization separation means for the center light source image and the size of the reflection surface of the reflection means are different from those of the light source image other than the center. An illuminating device characterized by being smaller than the size of the reflecting surface of the reflecting means. 9. The illuminating device according to claim 7, wherein the polarization separation means for the central light source image and the reflection surface of the reflection means have a size other than the center. A lighting device, wherein the size of the reflecting surface is equal to the size of the reflecting surface of the reflecting means. 10. The illuminating device according to claim 3, wherein the polarized light separating means is configured such that any one of two linearly polarized light beams separated by the plurality of polarized light separating means has the same reflection direction. A lighting device characterized by being configured to be as follows. 11. The illuminating device according to claim 3, further comprising a deflecting means for changing a traveling direction of the outgoing light, on an emitting surface of the light flux reflected and emitted by the reflecting means of the polarization converting means. A lighting device, comprising: 12. The lighting device according to claim 1, wherein
The lighting device according to claim 1, further comprising an opening means for restricting incident light on an incident surface of the glass rod. 13. The illumination device according to claim 12, wherein said aperture means has an aperture for limiting incident light in a polarization separation direction of said polarization conversion means. 14. The lighting device according to claim 4, wherein
An illumination device, further comprising an opening means for restricting incident light on an incident surface of the light beam splitting means. 15. The illumination device according to claim 14, wherein said aperture means has an aperture for restricting incident light in a polarization separation direction of said polarization conversion means. 16. The illumination device according to claim 3, wherein the illumination device is arranged on an incident side of the polarization conversion unit,
An illumination device, further comprising a light shielding unit that shields a part of light incident on the polarization conversion unit. 17. The lighting device according to claim 3, wherein the polarization axis rotating means is a half-wave plate. 18. An illuminating device according to claim 1, wherein the luminous flux from the illuminating device is separated into a plurality of primary color lights, and an electric device modulates the luminous flux from the spectral device. A projection display device comprising: an optical device; and projection means for projecting light modulated by the electro-optical device. 19. The projection display apparatus according to claim 18, wherein said spectral unit is disposed between said polarization conversion unit and said electro-optical device.