JPH10319351A - Illuminator for projecting device and projecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illuminator capable of brightening illumination light to a light valve by a usual light source as it is and a projecting device using this illuminator. SOLUTION: A polarizing device 5 polarization separating to first, second polarization, converting the relevant second polarization to the first polarization and emitting both first polarization is provided in the vicinity of an emission surface of a second lens plate 3 of a fly eye integrator 4, and the polarizing device 5 is constituted so that plural polarizing beam splitters 5a and reflection mirrors 5b having a reflection plane are arranged side by side alternately in the direction orthogonally intersecting with an optical axis, and 1/2 wavelength plates 5c parallel to the optical axis are arranged between these polarizing beam splitters 5a and reflection mirrors 5b, and the light source light is polarized separated to first polarization transmitting through a polarized light separating part and emitted and second polarization reflected by the relevant polarized light separating part, and the relevant second polarization is converted to the first polarization through the 1/2 wavelength plates 5c, and the relevant first polarization is reflected/emitted by the reflection mirrors 5b, and the light valves 15R,... are irradiated by the relevant first polarization and the first polarization transmitting through the polarized light separating part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to light of three primary colors including red light (hereinafter referred to as "R light"), blue light (hereinafter referred to as "B light") and green light (hereinafter referred to as "G light"). A lighting device that separates the colors and makes them incident on liquid crystal light valves respectively arranged for the color light, and modulates the incident light with a liquid crystal light valve, synthesizes the modulated light into colors, and performs color projection with a projection optical system. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection device for projecting an image, and more particularly to an improvement in an illumination optical system that uses a reflection type light valve as a light valve and has good illumination efficiency for the light valve.

[0002]

2. Description of the Related Art Conventionally, light of a light source emitted from a light source is separated into three primary colors of R light, G light and B light, and a reflection type light valve is arranged for each color light, and the light enters the light valve. FIG. 7 shows an example of a projection device that modulates each color light with light or an electric signal for each color and emits the light, combines the emitted light with a color combining optical system, and projects a color projection image with a projection lens. Such devices are known.

In the figure, reference numeral 201 denotes a light source.
Is composed of a lamp and a concave mirror such as an elliptical mirror. Light emitted from the light source 201 is reflected by an R light reflecting dichroic mirror 202 disposed on the optical axis in a direction perpendicular to the incident optical axis. The light is color-separated into G light and B mixed light traveling in the same direction as the incident optical axis. Further, the mixed light is directed by a G light reflecting dichroic mirror 203 arranged on the optical axis to a direction perpendicular to the optical axis, that is, a G light traveling in a direction parallel to the R light, and a G light traveling in the same direction as the incident optical axis. And the B light that travels to the right.

As described above, each dichroic mirror 20
The R light, G light, and B light separated into three colors by 2, 203 are incident on polarization beam splitters (PBS) 204R, 204G, 204B arranged for each light.
Each polarization beam splitter 204R, 204G, 204B
Of the respective colors, the P-polarized light of each color transmitted in the direction of the optical axis incident thereon and the S-polarized light reflected by the polarization splitter and reflected in a direction perpendicular to the incident optical axis. .

[0005] Then, a polarization beam splitter 2 for each color.
04R, 204G, and 204B, only the reflected S-polarized light out of the light incident on the polarization beam splitter 204.
R, 204G, and 204B are incident on reflective light valves 205R, 205G, and 205B disposed near the exit surfaces. The P-polarized light of each color is discarded as unnecessary light.

Next, each reflection type light valve 205R,
The light (S-polarized light) incident on 205G and 205B is generated by a write light signal for each color light if these light valves 205R, 205G and 205B are of the optical writing type, or if they are of the electric writing type. The modulated light is subjected to a modulation action by an electric signal of each color light, and the modulated light is emitted as P-polarized light, and the other light is emitted as mixed light of both polarized lights while the incident S-polarized light remains.
04R, 204G, and 204B again, and only the modulated light is polarized beam splitters 204R, 204G, and 204B.
The light passes through the polarized light separating portion B and travels to be projected light. The unmodulated light is reflected by the polarization separation unit, travels backward toward the light source, and is discarded.

Here, the polarization beam splitter 204B
Is transmitted through the G light reflecting dichroic mirror 206 and travels in the same direction as the incident direction.
G light reflection / B light reflection / R light transmission dichroic mirror 2
At 07 it is reflected at right angles.

The G light modulated light transmitted through the polarization beam splitter 204G is reflected by the G light reflecting dichroic mirror 206, travels in the same direction as the B light, and reflects G light, B light reflected, and R light transmitted. The light is reflected by the dichroic mirror 207.

Further, the R light modulated light transmitted through the polarization beam splitter 204R passes through the dichroic mirror 207, is combined with the B light and G light modulated light, travels, and is projected as a color image by the projection lens 208. Is done.

[0010]

However, in such a conventional device, R light and G light separated into three colors are used.
The light and the B light are respectively incident on the polarization beam splitters 204R, 204G, and 204B arranged for each color, and the polarization beam splitters 204R, 204G, and 204B.
The light valves 205R, 205G, and 205B can illuminate only with the amount of S-polarized light because the P-polarized light transmitted through the light is discarded. Therefore, it is considered that the brightness of the projected color image is sufficient. I could not say it. In particular, in the case of a device that projects on a large screen, there has been a big problem.

In order to make the projected image brighter, first, the output of the light source 201 may be improved. However, doing so requires an increase in the amount of power required, a problem of cooling due to heat generation of the light source unit, and furthermore, a reduction in the amount of light. A new problem, such as the disposal of the waste light, increases with the increase.

Therefore, the present inventors have studied a method of brightening illumination light to a light valve while using a conventional light source, and have accomplished the present invention.

[0013]

In order to solve this problem, the invention described in claim 1 is a light source for emitting random polarized light, a first lens plate having a plurality of lenses in a plane, and a plurality of lenses. And a so-called fly-eye integrator composed of a second lens plate having a plane in which light emitted from the light source is decomposed into light beams determined by the apertures of each lens of the first lens plate. Is illuminated on the lens of the second lens plate, and the light emitted from the second lens plate is superimposed on the light valve to illuminate the light valve. The light emitted from the light source is polarized and separated into first and second polarized lights having vibrations in directions perpendicular to each other,
A polarizing device that converts the second polarized light into the first polarized light and emits both first polarized lights; the polarizing device includes a plurality of polarizing beam splitters and a reflecting mirror having a reflecting plane; A half-wave plate parallel to the optical axis is disposed between the polarizing beam splitter and the reflection mirror, and a polarizing beam splitter of the polarizing beam splitter is provided. The reflection surface of the reflection mirror adjacent to the polarization beam splitter is set to be parallel to each other, and the first polarization transmitted and emitted through the polarization separation unit by the polarization beam splitter of the polarization device, and reflected by the polarization separation unit. And the second polarized light to be polarized, and the second polarized light is
The light is converted into a first polarized light through a two-wavelength plate, and further, the first polarized light is reflected and emitted by the reflection mirror, and the first polarized light and the first polarized light transmitted through the polarization separation unit are converted into a light valve. And a lighting device for a projection device for irradiating the light.

According to a second aspect of the present invention, there is provided a light source for emitting randomly polarized light, a first lens plate having a plurality of lenses in a plane, and a second lens plate having a plurality of lenses in a plane. A so-called fly-eye integrator, which decomposes light emitted from the light source into light fluxes determined by the apertures of each lens of the first lens plate, and condenses each light beam on a lens of the second lens plate. , The second
An illumination device for a projection device that illuminates light emitted from a lens plate by superimposing the light on a light valve, wherein the light emitted from the light source vibrates in a direction perpendicular to each other near an emission surface of the second lens plate. And a polarizing device that converts the first polarized light into the second polarized light and emits both the second polarized lights, wherein the polarizing device includes a plurality of polarizing beam splitters. And a reflection mirror having a reflection plane are alternately arranged in a direction perpendicular to the optical axis, and transmit and emit the polarized light separating portion of the polarized light separated by the polarizing beam splitter. A half-wave plate is provided on the exit surface, and a polarization splitting portion of the polarization beam splitter and a reflection surface of a reflection mirror adjacent to the polarization beam splitter are set to be parallel to each other. The splitter, transmitted through the polarization separation section, and the first polarized light emitted by polarized separated into a second polarized light reflected by the polarization separating part, the first polarization, the 1
The second polarized light is converted into the second polarized light by the
The polarized light is reflected by the reflection mirror and emitted from a polarizing device, and the second polarized light and the second polarized light converted by the half-wave plate are irradiated to a light valve. The device is characterized in that:

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, a plurality of field lenses are arranged between the polarizing device and the light valve.

According to a fourth aspect of the present invention, there is provided an illumination device, a light valve as modulation means for modulating illumination light from the illumination device with image information and emitting the light as light containing the modulated light. 2. A projection apparatus comprising: a light detecting unit that detects the light emitted from the light valve; and a projection optical system that projects the detected light.
4. A projection device, which is the illumination device for a projection device according to any one of the above aspects.

According to a fifth aspect of the present invention, in addition to the configuration of the fourth aspect, the light valve is a reflection type light valve, and the light analyzing means is a polarization beam splitter. .

According to a sixth aspect of the present invention, in addition to the configuration of the fourth aspect, the light valve is a transmission type light valve, and the light analyzing means is a polarizing plate.

[0019]

Embodiments of the present invention will be described below.

[First Embodiment of the Invention] FIGS. 1 to 6 show a first embodiment of the present invention.

FIG. 1 is a block diagram showing the whole of a projection device using the lighting device according to the present invention.

Reference numeral 1 in the figure denotes a light source composed of a lamp and a concave mirror such as an elliptical mirror. The light source 1 emits a randomly polarized light source.

The light from the light source is converted into a substantially parallel light beam by a shaping lens (not shown), and further passes through an infrared absorption filter (not shown) and an ultraviolet absorption filter (not shown).
The light is incident on a fly-eye integrator 4 composed of the lens plate 2 and the second lens plate 3. Each of the first and second lens plates 2 and 3 has a plurality of lenses 2a and 3a formed in a plane as shown in FIGS.

Thereafter, random polarized light is incident on the field lens 6 via the polarizing device 5 disposed near the exit surface of the second lens 3.

As shown in FIG.
A plurality of prism-shaped polarization beam splitters 5a extending in the vertical direction and reflection mirrors 5b having reflection planes are alternately arranged in a direction orthogonal to the optical axis, and the polarization beam splitter 5a and the reflection mirror are arranged. A half-wave plate 5c parallel to the optical axis is disposed between the half-wave plate 5c and the half-wave plate 5b. The polarization splitting portion of the polarization beam splitter 5a and the reflection surface of the reflection mirror 5b adjacent to the polarization beam splitter 5a are set parallel to each other.

The light source light incident on the polarization beam splitter 5a passes through the polarization splitting portion of the polarization beam splitter 5a and travels and exits as it is. The P-polarized light as the "first polarization" and the polarization of the polarization beam splitter 5a. The light is separated into S-polarized light as “second polarized light” reflected by the separation unit. The S-polarized light is converted into P-polarized light by the half-wave plate 5c, reflected by the reflection mirror 5b, and emitted.

The two P-polarized lights emitted by the polarizer 5 in this manner enter the cross dichroic mirror 7 via the field lens 6. The cross dichroic mirror 7 is arranged in an X-shape so that a dichroic mirror 8 that reflects R light and G light and a dichroic mirror 9 that reflects B light are orthogonal to each other.

Here, the separated B light travels in a direction orthogonal to the incident optical axis, the traveling direction is changed to a right angle by the bending mirror 10, and further travels through the B light field lens 11B. , Polarizing beam splitter for B light (polarizing beam splitter) as "polarization separating means, analyzing means"
It is incident on 12B.

The mixed R and G light separated by the cross dichroic mirror 7 travels by changing the optical axis to a right angle by the bending mirror 13 and is arranged at an incident angle of 45 degrees with respect to the optical axis. G light reflection dichroic mirror 1
R, which enters and transmits through and travels in the same direction as the incident optical axis.
The light is color-separated into light and G light reflected in a direction perpendicular to the light, and enters the polarization beam splitters 12R and 12G for the respective color lights via the field lenses 11R and 11G, respectively.

As described above, the polarization beam splitters 12R,
The P-polarized light of each color incident on 12G and 12B is transmitted through the polarization splitting units of the polarization beam splitters 12R, 12G and 12B and emitted.

Each of the polarization beam splitters 12R, 12G,
The P-polarized light of each color emitted through the 12B is reflected by the reflection type light valve 15R, 15G, 15 disposed near the emission surface of the polarization beam splitter 12R, 12G, 12B for each color light.
It is incident on B and illuminated.

As described above, each color light valve 15R,
Illumination for 15G, 15B has been described. Thus, according to the present invention, the S-polarized light which is conventionally discarded can be converted into the P-polarized light by the polarizing device 5 as described above and can contribute to the illumination of the light valves 15R, 15G, and 15B. Can be achieved.

Then, each of the light valves 15R, 15G,
The P-polarized illumination light incident on 15B is modulated by image signals of the light valves 15R, 15G, and 15B. The modulated light becomes S-polarized light and is mixed with unmodulated light (P-polarized light) as mixed light.
G, 15B, and only the modulated light is reflected by the polarization splitters of the polarization beam splitters 12R, 12G, 12B for each color light, and the unmodulated light is transmitted and discarded, thereby achieving the light detection.

Each of the polarization beam splitters 12R, 12G,
The analysis light reflected and emitted from 12B enters the cross dichroic prism 18 constituting the color combining optical system from different entrance surfaces. And the prism 1
B light reflecting dichroic film 18B and R light reflecting dichroic film 18
By R, the incident R light is reflected by the dichroic film 18R, the B light is reflected by the dichroic film 18B in the same direction, and the G light is reflected by the two films 18B, 18R.
, And travels in the same direction to achieve color synthesis, is emitted as full-color projection light, enters a projection lens 19 as a “projection optical system”, and forms a high-brightness color image on a screen (not shown). Projected.

Here, the illumination optical system for each of the light valves 15R, 15G and 15B as an object to be illuminated according to the present invention will be described in further detail.

FIG. 2 shows the light valve 15 of the projection device.
FIG. 3 shows a main part of an illumination optical system for R, 15G, and 15B and a ray diagram thereof. Originally, R light, G light and B light should be described. However, the three light valves 15R and 15G have the same optical path length and the same basic configuration for all three colors. , 15
B as a light valve 15, and the polarizing beam splitters 12R, 12G, and 12B are also referred to as the polarizing beam splitters 12, and the field lenses 11R, 11G,
11B is also described as the field lens 11. In addition,
Here, illustration of the three-color separation / synthesis optical system and the bending mirror is omitted.

FIG. 3 is a perspective view showing the shape of the first lens plate 2. As shown in this figure, the surface has a configuration in which 5 × 5 convex lenses 2a are arranged in a plane, and the surface opposite to the formation of the lens 2a is a plane.

The outer shape of the second lens plate 3 is substantially the same as that of the first lens plate 2 of FIG. 2, and the arrangement of the lenses 3a formed of convex lenses on the surface is the same as that of the first lens plate 2. It is the same array as 2 and 5 × 5. However, the shape of the lens 3a differs between the first lens plate 2 and the second lens plate 3. Lens 2 of first lens plate 2 and second lens plate 3
This is because a and 3a have different purposes.

In the first embodiment, the light source light from the light source 1 is shaped into a substantially parallel light beam by a shaping optical system (not shown) and is incident on the first lens plate 2. Each parallel light beam incident on the aperture determined by the individual lens 3
It is set to converge on a. That is, the first
The second lens plate 3 is positioned substantially at the focal point of the lens 2a of the lens plate 2.
The shape of the lens 2a of the first lens plate 2 and the position of the second lens plate 3 are determined so that the lens 3a is disposed. Further, the light spot on the lens 2 a of the first lens plate 2 is changed by the opposing lens 3 a on the second lens plate 3.
The second lens plate 3 is formed so as to form an image on the light valve 15 via the field lens 6 and the field lens 11.
Of the lens 3a is determined.

As described above, the polarizing device 5 includes a plurality of polarizing beam splitters 5a each formed of a rectangular parallelepiped having a square cross-section, as shown in FIG. A half-wave plate 5c is disposed between the polarization beam splitters 5a, and is attached to the S-polarized light exit surface of the incident light reflected by the polarization separation unit,
Further, a reflection mirror 5b is provided which reflects the light converted into P-polarized light via the wave plate 5c and reflects the light. In the present embodiment, the reflecting mirror 5b forms a reflecting plate by coating a surface (bottom surface) corresponding to the right angle of the right-angled triangular prism with a reflecting metal such as aluminum. Note that the width of the triangular prism is the same as that of the polarization beam splitter 5a, and one surface of the slope sandwiching the right angle of the triangular prism is bonded to the side surface of the adjacent polarization beam splitter 5a with an adhesive.

Further, how the first lens plate 2, the second lens plate 3, and the field lenses 6 and 11 form an image on the light valve 15 will be described with reference to FIGS. 6 and 7 in addition to FIG. I do.

FIG. 2 shows the polarization beam splitter of the polarization device 5 for the two outermost rays of the opening formed by the lens 2a of the first lens plate 2 and the three rays which enter the center parallel to the optical axis. 5A is a ray diagram illustrating a state of condensing the P-polarized light transmitted through the polarization separation unit 5a on the light valve 15 first, and illustrates a light beam of a light beam incident on each lens 2a of the first lens plate 2. FIG.

The position at which the polarizing device 5 is disposed is such that a light beam passing through the center of the lens 2a of the first lens plate 2 and the corresponding lens 3a of the second lens plate 3 is positioned at the second lens plate 3
It is necessary to transmit the light through the lens 3a and enter the polarization beam splitter 5a of the polarization device 5 at substantially the center.

Of the light rays entering each opening of the first lens plate 2, the light rays incident parallel to the optical axis and passing through the center of each opening are the first lens plate 2 of the second lens plate 3. The P-polarized light that passes through the central portion of the lens 3a facing the opening, enters the polarization device 5, and passes through the polarization separation portion of the polarization beam splitter 5a constituting the polarization device 5, and is reflected by the polarization separation portion. The light is polarized and separated into S-polarized light. The P-polarized light that passes through and exits the polarizing device 5 travels parallel to the optical axis (that is, while maintaining telecentric characteristics), passes through the polarizing beam splitter 12 by the field lenses 6 and 11, and passes through the light valve. The light is condensed at approximately the center of the reference numeral 15.

The light beam of the optical axis passing through the center of each lens 2a, 3a of the first lens plate 2 and the second lens plate 3 is reflected by the polarization beam splitter of the polarization beam splitter 5a of the polarization device 5. For the S-polarized light, an enlarged partial explanatory view of the arrangement of the polarizing device 5 in FIG. As shown in the figure, only the light beam is shown), the light enters the substantially central portion of the polarization beam splitter 5a, enters the polarization beam splitting portion of the polarization beam splitter 5a at an incident angle of 45 degrees, is reflected and proceeds. The reflection mirror 5b is converted into P-polarized light via a half-wave plate 5c attached to the exit surface of the polarization beam splitter 5a, and has an incident angle of 45 degrees with respect to an optical axis arranged adjacently. (The bottom surface of the right-angled triangular prism), is reflected and is reflected by an optical axis parallel to the incident optical axis (ie,
Injected (while maintaining telecentric properties). The light beam reflected by the reflection mirror 5b passes through the field lenses 6 and 11 and passes through the polarization beam splitter 12 because it is P-polarized light, as shown in the entire ray diagram of FIG. The light is condensed on a central portion on the optical axis.

Further, as shown in FIG.
The light rays incident on the upper portions of the respective apertures in parallel with each other with respect to the optical axis are different from the configuration in which the second lens plate 3 is disposed at the focal position of the lens 2a of the first lens plate 2 as described above.
At the center of the lens 3 a of the second lens plate 3, the light passes through the center of the opening on the first lens plate 2, intersects with the light, and is incident on the polarizing device 5 to form the polarizing device 5. The P-polarized light, which is polarized and separated by the polarization splitting portion of the polarizing beam splitter 5a and transmitted and emitted as it is, is condensed on the lower portion of the light valve 15 by the field lenses 6 and 11. Of the incident light, the S-polarized light reflected by the polarization splitting film of the polarization beam splitter 5a of the polarization device 5 is, as shown in the enlarged explanatory view of FIG. 5, 1 / formed on the exit surface of the polarization beam splitter 5a. The light is converted into P-polarized light through the two-wavelength plate 5c, and is reflected by the adjacent reflection mirror 5b.
And exits the polarizing device 5, travels with a predetermined inclination with respect to the optical axis, passes through the field lenses 6 and 11,
As shown in the overall view of FIG. 6, the P-polarized light transmitted through the polarization beam splitter 5a shown in FIG. You.

Further, as shown in FIG. 2, light rays which are incident on the lower part of each opening of the first lens plate 2 in parallel to the optical axis with each other are reflected by the lens 2a of the first lens plate 2 as described above. From the configuration in which the second lens plate 3 is arranged at the focal position,
At the center of the lens 3a of the second lens plate 3, the light crosses and passes through the center of the opening on the first lens plate 2, is transmitted, enters the polarizing device 5, and is polarized by the polarizing beam splitter of the polarizing device 5. The P-polarized light, which is polarized and separated by the polarized light separating unit 5a and transmitted as it is, is condensed by the field lenses 6 and 11 on the upper part of the light valve 15 in the figure.

As shown in the enlarged explanatory view of FIG. 5, the S-polarized light of the incident light reflected by the polarization separation unit of the polarization device 5 is a half-wave plate formed on the exit surface of the polarization beam splitter 5a. The light is converted into P-polarized light by 5c, is incident on the reflection mirror 5b, is reflected by the mirror 5b according to the law of reflection, travels with a predetermined inclination with respect to the optical axis, passes through the field lenses 6 and 11, As shown in the overall view of FIG. 6, the light is condensed on the light valve 15 at the same position as the light condensing point on the light valve 15 for the P-polarized light transmitted through the polarizer 5 shown in FIG. .

As described above, of the randomly polarized light source light transmitted through the second lens plate 3 and incident on the polarizing device 5, the P-polarized light transmitted through the polarizing device 5 and illuminating the light valve 15 is used. In addition, the S-polarized light reflected by the polarization beam splitter of the polarization beam splitter 5a of the polarization device 5 is 、 -polarized on the exit surface of the polarization beam splitter 5a.
The light is converted into P-polarized light by passing through the wave plate 5c, and the P-polarized light is incident on and reflected by the reflecting mirror 5b disposed at an incident angle of 45 degrees with respect to the optical axis, and the polarizing device 5 is emitted. This allows the P-polarized light to pass through the analyzing polarization beam splitter 12 disposed immediately before the light valve 15 and illuminate the light valve 15.

That is, conventionally discarded S-polarized light is
According to the present invention, the polarized light is converted into P-polarized light, which can be incident on the light valve 15 and contribute to illumination.
The light source light is incident on the polarizing device 5 and is superimposed on the P-polarized light that passes through the polarizing device 5 as it is and illuminates the light valve 15, thereby achieving high-luminance illumination. Even so, it is possible to achieve a great effect that high brightness of the projected image can be achieved. Further, in the present invention, since the so-called fly-eye integrator 4 using the first lens plate 2 and the second lens plate 3 is used, the first lens plate 2 is divided by individual apertures of the lens 2a. Since the light beam is superimposed on the light valve 15 by the lens 3a of the second lens plate 3, the effect of achieving uniform illumination can be achieved in addition to the effect described above.

Further, the polarizer 5 having the arrangement shown in FIG. 2 may be arranged so as to be rotated by 90 degrees with respect to the optical axis. Adopting such an arrangement is a
Polarizing beam splitter 1 for analysis arranged close to 5
Since the polarized light reflected on the two polarization splitters is incident on the polarization beam splitter 12, the light valve 15 needs to be arranged near the exit surface reflected and emitted by the polarization splitter. .

At this time, the analysis light becomes light transmitted through the polarization splitting portion of the polarization beam splitter 12.

[Second Embodiment of the Invention] The First Embodiment
In the polarization device 5 described above, the S / polarized light reflected by the polarization splitters of the plurality of polarization beam splitters 5a is exposed to 1 /
Although the two-wavelength plate 5c is arranged, in the second embodiment, the polarization beam splitter 5 of the polarization device 5 of the light source light is used.
A half-wave plate 5c is arranged on the exit surface of the polarization beam splitter 5a so as to change the P-polarized light passing through a to the S-polarized light, and the S-polarized light reflected by the polarization separation unit of the polarization beam splitter 5a is The half-wave plate 5c is not disposed on the exit surface, and the S-polarized light is reflected by the adjacent reflection mirror 5b.

The ray diagram obtained by the polarizing device 5 having the above configuration is basically the same as the ray diagram of the first embodiment, and therefore will not be described.

However, since the polarized light emitted from the polarization device 5 becomes S-polarized light as described above, the light valve 15 cannot be arranged as it is at the position shown in FIG. In order to be reflected by the polarization beam splitter 12, a light valve is disposed at a conjugate position of the illustrated light valve 15 with respect to the polarization separation portion of the polarization beam splitter 12, or A half-wave plate is placed before the polarization
It needs to be converted to polarized light.

In the second embodiment as well, similarly to the first embodiment, the illumination by the polarized light transmitted through the polarization device 5 is superimposed with the polarized light reflected by the polarization splitting section of the polarization beam splitter 12 to write the light. Since the bulb 15 can be illuminated, high-luminance illumination can be achieved, and illumination efficiency can be improved.

The optical system for illuminating the projection apparatus described so far includes the polarization beam splitter 5 constituting the polarization apparatus 5.
The polarization splitting portion a is reflected (Embodiment 1) or transmitted (Embodiment 2), and a wavelength plate film is attached as a half-wave plate 5c disposed on the exit surface of the polarization beam splitter 5a. P-polarized light (Embodiment 1) or S-polarized light (Embodiment 2) by passing through the wave plate 5c.
Was converted to the other half-wave plate 5c
As an example, a configuration in which a half-wave plate layer is formed on the surface of the polarizing beam splitter 5a by an oblique evaporation method or the like may be used. In this case, a titanium dioxide (TiO2) layer or the like may be formed on the surface of the polarization beam splitter 5a by oblique evaporation at a predetermined film thickness and pressure. If only an evaporation mask is prepared, the polarization beam splitter 5a can be accurately formed. Can be formed. Even in the case of this method, it is needless to say that the fast axis as the half-wave plate 5c can be formed in a predetermined direction by controlling the inclination direction of the substrate during film formation.

Further, as shown in FIG. 1, the projection device using the reflection type light valve 15 as the light valve as shown in FIG. 1 and the projection device using the transmission type light valve as shown in FIG. As the device, the lighting device for a projection device according to the present invention can be used. In this case, the polarization beam splitter 1 for analysis shown in FIG.
The role of 2 is two polarizing plates constituting a cross Nicol sandwiching a transmission type light valve from both sides,
When the illumination device for a projection device according to the present invention is used, it is configured such that linearly polarized light having a vibration direction in a predetermined direction incident on the light valve is transmitted through the polarizing plate on the incident side, and the light valve is modulated. The present invention achieves light detection by configuring a polarizing plate disposed on the light-exiting side in a direction absorbing non-modulated light so that only modulated light emitted from the light valve is modulated by a signal and transmitted therethrough. Can be proposed.

[0059]

As described above, according to the invention described in each claim, one of the first polarized light or the second polarized light, which was conventionally discarded, is converted into the other by the polarizing device, and the light valve is thus disposed. Not only can the amount of light illuminating the light valve be significantly improved, but also the uniformity can be achieved because the configuration employing a so-called fly-eye integrator is the basis of the present invention. Thus, an effect of illuminating the light valve can be obtained.

According to the invention as set forth in any one of claims 4 to 6, when the illumination device according to the present invention is employed in a projection device, a color projection image with high luminance and no illumination unevenness is obtained. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a projection device according to Embodiment 1 of the present invention.

FIG. 2 is a schematic diagram showing an illumination optical system for a light valve of the projection device according to the first embodiment.

FIG. 3 is a perspective view of a first lens plate used in the projection device according to the first embodiment.

FIG. 4 is a perspective view of the polarizing device according to the first embodiment.

FIG. 5 relates to the first embodiment, and in the illumination optical system shown in FIG. 2, three light rays incident on the lens at the center of the first lens plate are reflected by the polarizing beam splitter and the reflecting mirror constituting the polarizing device. FIG. 7 is an enlarged explanatory light ray diagram for explaining a state of being performed.

FIG. 6 is an overall ray diagram showing a state of illuminating the three-light valve of FIG. 5 according to the first embodiment.

FIG. 7 is an explanatory view showing a conventional projection device.

[Description of Signs] 1 light source 2 first lens plate 2a lens 3 second lens plate 3a lens 4 fly-eye integrator 5 polarizing device 5a polarizing beam splitter 5b reflection mirror 5c 1/2 wavelength plate 6 field lens 8 R light / G light Reflection dichroic mirror 9 B light reflection dichroic mirror 10, 13 Folding mirror 11, 11B, 11R, 11G Field lens 12, 12R, 12G, 12B Polarization beam splitter (polarization separation means, analysis means) 14 G light reflection dichroic mirror 15 , 15R, 15G, 15B Reflective light valve 18 Cross dichroic prism 19 Projection lens (projection optical system)

Claims (6)

[Claims] 1. A light source for emitting randomly polarized light, a so-called fly-eye integrator comprising a first lens plate having a plurality of lenses in a plane and a second lens plate having a plurality of lenses in a plane. Decomposing the light emitted from the light source into light beams determined by the apertures of the lenses of the first lens plate, condensing each light beam on the lens of the second lens plate, What is claimed is: 1. A lighting device for a projection device, wherein a light emitted from said light source is vibrated in directions perpendicular to each other near an emission surface of said second lens plate. , Second
A polarizing device that separates the polarized light into polarized light, converts the second polarized light into the first polarized light, and emits both first polarized lights, the polarizing device including a plurality of polarization beam splitters and a reflection having a reflection plane. Mirrors are alternately arranged in a direction orthogonal to the optical axis, and a half-wave plate parallel to the optical axis is arranged between the polarizing beam splitter and the reflecting mirror; The polarization splitter of the splitter and the reflection surface of the reflection mirror adjacent to the polarization beam splitter are set in parallel with each other, and the polarization beam splitter of the polarization device transmits and emits the first polarized light through the polarization splitter, The polarized light is separated into the second polarized light reflected by the polarized light separating unit, and the second polarized light is converted into the first polarized light through the half-wave plate, and further, the first polarized light is reflected by the reflection mirror. Reflected, emitted, A first polarization and a first polarized light transmitted through the polarization separating part,
An illumination device for a projection device, wherein the illumination device irradiates a light valve. 2. A light source for emitting randomly polarized light, and a so-called fly-eye integrator comprising a first lens plate having a plurality of lenses in a plane and a second lens plate having a plurality of lenses in a plane. Decomposing the light emitted from the light source into light beams determined by the apertures of the lenses of the first lens plate, condensing each light beam on the lens of the second lens plate, What is claimed is: 1. A lighting device for a projection device, wherein a light emitted from said light source is vibrated in directions perpendicular to each other near an emission surface of said second lens plate. , Second
A polarizing device that separates the polarized light into polarized light, converts the first polarized light into a second polarized light, and emits both second polarized lights, the polarizing device including a plurality of polarization beam splitters and a reflection surface having a reflection plane. Mirrors are alternately arranged in a direction orthogonal to the optical axis, and a half of the exit surface for transmitting and exiting the polarized light separating portion of the polarized light separated by the polarizing beam splitter is emitted. A wavelength plate is provided, a polarization splitting unit of the polarization beam splitter, and a reflection surface of a reflection mirror adjacent to the polarization beam splitter are set to be parallel to each other. The first polarized light that is transmitted and emitted is separated into the second polarized light that is reflected by the polarized light separating unit, and the first polarized light is converted into the second polarized light by the half-wave plate. Said 2 polarization, reflected by the reflection mirror, is emitted from the polarization apparatus, wherein with the second polarization 1/2
A lighting device for a projection device, wherein the second polarized light converted by the wavelength plate is irradiated to a light valve. 3. The illumination device for a projection device according to claim 1, wherein a plurality of field lenses are arranged between said polarizing device and said light valve. 4. An illumination device, a light valve as modulation means for modulating illumination light from the illumination device according to image information, and emitting the modulated light as light, and analyzing the light valve emission light. And a projection optical system for projecting the analysis light, wherein the illumination device is the illumination device for a projection device according to claim 1. Projection device. 5. The projection apparatus according to claim 4, wherein said light valve is a reflection type light valve, and said light detecting means is a polarization beam splitter. 6. The light valve according to claim 4, wherein the light valve is a transmissive light valve, and the light analyzing means is a polarizing plate.
3. The projection device according to claim 1.