JP2002214565A - Projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily perform such regulation as to align an illumination region for illumination light of color passing a relay optical system and an illumination region of illumination light of other colors. SOLUTION: This projector has an illumination optical system, a color light separation optical system for separating the illumination light emitted from the illumination optical system to the illumination light rays of the plural colors, plural electro-optic devices for converting the illumination light rays of the plural colors to the light rays meeting the color signals respectively corresponding thereto, a color synthesis optical system for synthesizing the converted light rays of the plural colors emitted from the plural electro-optic devices and emitting the light indicating color images and a projection optical system for projecting the color images indicated by the synthesized light emitted from the color synthesis optical system. Further, the projector has the relay optical system in the route of the illumination light of at least one color among the illumination light rays of the plural colors emitted from the color separation optical system. The relay optical system has a regulator for regulating the position along the optical axis direction of at least one lens among the plural lenses included in the relay optical system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a projector (projection display device) for projecting an image.

[0002]

2. Description of the Related Art In general, a projector for projecting a color image includes an illumination optical system for emitting illumination light, a color light separation optical system for separating illumination light into three colors of illumination light, and three colors of illumination light. Three light valves for converting (modulating) light corresponding to corresponding color signals, a color light combining optical system for combining three colors of converted light (modulated light) emitted from the three light valves, and a color light combining optical system And a projection optical system that projects an image represented by the combined light emitted from the projector. Electro-optical devices such as liquid crystal panels are used as light valves. Hereinafter, a projector having three light bubbles for three colors is referred to as a “three-panel projector”.

It is preferable that the image projected by the projector is brighter, and it is desired that the illumination light efficiently illuminates the light incident surface of the light valve. For this reason, some conventional projectors adjust the size of the illumination area by adjusting the projection magnification of the illumination light emitted from the illumination optical system.

[0004]

However, in the conventional projector, the size of the illumination area of the separated illumination light of each color is commonly changed, and the size of the illumination area is adjusted for each illumination light of each color. There is a problem that you can not. In particular, in a three-plate projector, of the illumination light path from the illumination optical system to the light valve for each color,
There may be a path that is longer than others. A relay optical system is often provided in such a long path, and more components of the optical system that affect the size of the illumination area are provided as compared with other paths.
For this reason, there is a demand for a technology that can easily perform adjustment such that the illumination region of the illumination light of the color passing through the path where the relay optical system exists and the illumination region of the illumination light of another color are matched. Was.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and comprises an illumination area of illumination light of a color passing through a relay optical system and an illumination area of illumination light of another color. It is an object of the present invention to provide a technique capable of easily performing adjustment for matching.

[0006]

In order to solve at least a part of the above problems, an apparatus according to the present invention is a projector for projecting an image, comprising: an illumination optical system; Illumination light emitted from, a color light separation optical system for separating the illumination light of a plurality of colors, and a plurality of electro-optical devices for converting the illumination light of the plurality of colors into light corresponding to the corresponding color signal, A color light combining optical system that emits light representing a color image by combining converted lights of a plurality of colors emitted from the plurality of electro-optical devices, and project a color image represented by the combined light emitted from the color light combining optical system. Projection optical system, further comprising a relay optical system in the path of at least one color of the illumination light of a plurality of colors emitted from the color light separation optical system, the relay optical system, For relay optics Of Murrell plurality of lenses, characterized in that it has an adjusting device for adjusting the position along the optical axis direction of the at least one lens.

According to the projector of the present invention, the position of at least one lens included in the relay optical system along the optical axis direction can be adjusted, so that the size of the illumination area of the illumination light passing through the relay optical system can be increased. This can be adjusted independently of the size of the illumination area with other colors of illumination light. Therefore, it is possible to easily perform adjustment such that the illumination area of the illumination light of the color passing through the relay optical system is matched with the illumination area of the illumination light of another color. In this specification, the phrase "matching the illumination areas" means adjusting the relationship between the illumination areas of each color so as to improve the image quality of the projected color image.

The color light separation optical system separates the illumination light emitted from the illumination optical system into three colors of illumination light,
A relay optical system provided in a path of two-color illumination light among the three-color illumination light emitted from the color light separation optical system,
Each of the relay optical systems may include an adjusting device that adjusts a position of at least one of the plurality of lenses included in each of the relay optical systems along the optical axis direction.

With this arrangement, the size of the illumination region of the two colors of illumination light can be adjusted independently of the illumination region of the three colors of illumination light. If the size of the illumination area is appropriately set, as a result, the size of the illumination area for each of the three colors of illumination light can be appropriately set. Therefore, adjustment for matching the illumination areas of the three colors of illumination light can be further facilitated.

Here, it is preferable that the at least one lens includes a relay lens.

With this configuration, the size of the illumination area can be adjusted without changing the incident angle of the color light for illuminating the corresponding electro-optical device.

It is preferable that the adjusting device is further capable of adjusting positions in two axial directions perpendicular to the optical axis direction and perpendicular to each other.

With this configuration, it is possible to adjust the position of the illumination area in two axial directions perpendicular to the optical axis direction and perpendicular to each other.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples.

A. FIG. 1 is a schematic plan view showing a main part of an optical system of a projector as a first embodiment of the present invention. This projector PJ1 has an illumination optical system 1
00, a color light separation optical system 200, and a relay optical system 300
And three light valves 400R, 400G, 400B
, A cross dichroic prism 500, and a projection lens 600. The components of each optical system are arranged substantially horizontally around the cross dichroic prism 500.

The illumination optical system 100 includes a light source 110 and a first
Lens array 120 and second lens array 130
, A polarization conversion element 140, and a superposition lens 150. The light beam emitted from the light source 110 is divided into a plurality of minute partial light beams by the first lens array 120, and each of the light beams is divided into three light beams by the second lens array 130 and the superimposing lens 150. The light valves 400R, 400G, and 400B are superimposed on the light incident surfaces. That is, the first lens array 120,
The second lens array 130 and the superimposing lens 150
Three light valves 400R and 400 to be illuminated
An integrator illumination optical system that illuminates G and 400B almost uniformly is configured. The polarization conversion element 140 has a function of aligning non-polarized light with polarized light having a polarization direction that can be used by the three light valves 400R, 400G, and 400B.

The illumination optical system 100 includes the illumination optical system 1
A reflecting mirror can also be provided according to the arrangement of each component constituting 00.

The illumination optical system is not limited to the illumination optical system 100 of the present embodiment, but may have any configuration as long as it can illuminate the three light valves 400R, 400G, and 400B. There may be.

The color light separation optical system 200 includes the illumination optical system 10.
Illumination light emitted from 0
It has a function of separating into color light (illumination light). The first dichroic mirror 210 transmits substantially red (R) light and reflects light of a shorter wavelength (light of substantially green (G) and blue (B)) than the transmitted color light. I do. The R light transmitted through the first dichroic mirror 210 is reflected by the reflection mirror 230, and
The light valve 400R for R is illuminated through 40.
The field lens 240 receives the plurality of partial light beams from the illumination optical system 100,
Light is collected so as to illuminate R. Usually, each partial ray bundle is
The light beams are set to be substantially parallel light beams.
The same applies to the field lenses 250 and 350 provided in front of the other light valves 400G and 400B.

Of the G light and B light reflected by the first dichroic mirror 210, the G light is reflected by the second dichroic mirror 220 and
The light valve 400G for G is illuminated through 50.
On the other hand, the B light passes through the second dichroic mirror 220, passes through the relay optical system 300, and illuminates the B light valve 400B.

These dichroic mirrors are
It can be manufactured by forming a dielectric multilayer film corresponding to each function on a transparent glass plate.

The relay optical system 300 includes the entrance lens 31
0, the first reflection mirror 320, and the relay lens 330
, A second reflection mirror 340, and an emission-side lens (field lens) 350. Illumination optical system 100
The B light emitted from the color light separating optical system 200 converges near the relay lens 330 by the incident side lens 310 and diverges toward the emission side lens 350. The size of the light beam entering the exit lens 350 is set to be substantially equal to the size of the light beam entering the incident lens 310.

The reason why the relay optical system 300 is provided in the path of the B light is as follows. That is, each of the plurality of partial light beams emitted from the illumination optical system 100 is a divergent light beam. The path of the B light is longer than the paths of the other color lights by an amount corresponding to the path in which the relay optical system 300 is arranged. Therefore, when the relay optical system 300 is not provided in the path of the B light, the illumination area of the B light valve 400B illuminated by the B light is larger than the illumination area of the light valve illuminated by the other color lights. Thus, the illumination efficiency of the B light decreases. That is, the relay optical system 3 is applied to the B light.
The reason why 00 is provided is to suppress a decrease in illumination efficiency caused by the path of the B light being longer than the light of other colors.

The illumination area of the B light valve 400B illuminated by the B light will be further described later.

Light valves 400R, 400 for each color
G and 400B convert the color light incident from each light incident surface into light corresponding to a corresponding color signal (image information), and emit the converted light as transmitted light. A transmissive liquid crystal panel is used as such a transmissive light valve. These light valves 400R, 400R
G and 400B correspond to the electro-optical device of the present invention.

The cross dichroic prism 500 is
It has a function as a color light combining optical system that combines the converted light of each color emitted from the light valves 400R, 400G, and 400B for each color to emit light representing a color image. The cross dichroic prism 500 includes an R light reflecting dichroic surface 510R that reflects R light and a B light reflecting dichroic surface 510B that reflects B light. R
The light reflecting dichroic surface 510R and the B light reflecting dichroic surface 510B are a dielectric multilayer film that reflects R light,
This is provided by forming a dielectric multilayer film that reflects B light in an approximately X-shape at the interface between the four right-angle prisms. The converted lights of three colors are combined by the two dichroic surfaces 510R and 510B to form light representing a color image. The combined light generated by the cross dichroic prism 500 is emitted toward the projection lens 600. The projection lens 600 projects an image represented by the combined light. The projection lens 600 has a function as a projection optical system that displays an image. The color light combining optical system may include a cross dichroic mirror instead of a cross dichroic prism.

FIG. 2 is an explanatory diagram showing the relay lens 330 in an enlarged manner. The relay lens 330 is connected to the stage 36
It is attached to 0. The stage 360 includes a holder 362 that holds the relay lens 330. The holder 362 is fixed on the table 363. The table 363 is provided movably along a guide rail 364 provided on the base 361. A long screw groove 365 is provided on the guide rail 364 along the moving direction of the table 363, and the table 363 can be fixed at an arbitrary position along the optical axis direction on the guide rail 362 by the bolt 365. it can. Therefore, the position of the relay lens 330 in the optical axis direction can be adjusted by the stage 360. Note that the stage 360 corresponds to the adjusting device of the present invention.

FIG. 3 is an explanatory diagram showing the relationship between the position of the relay lens 330 and the illumination area of the illumination light for illuminating the B light valve 400B. FIG. 3A shows the relay optical system 300 with the two mirrors 320 and 340 omitted. FIG. 3B shows a light valve 400B for B.
2 shows an illumination area of illumination light for illuminating the light incident surface LI. Assuming that the position of the relay lens 330 is the position B in FIG. 3A, when the position of the relay lens 330 is the position A, as shown in FIG. 3B, the illumination area LB ( The illumination area LA (the area within the long dashed line frame) can be larger than the illumination area LA (the area within the solid line frame).
When the position of the relay lens 330 is the position C, the illumination area LC (the area within the short dashed frame) can be smaller than the illumination area LB at the position B. In other words, when the relay lens 330 is separated from the light valve 400B, the illumination area can be increased, and when the relay lens 330 is set closer to the light valve 400B, the illumination area can be reduced. .

In each of the components constituting the relay optical system 300, since the optical characteristics actually fluctuate, the size of the illumination area illuminated by the B light changes, or light loss occurs. This changes the lighting efficiency. However, in the present embodiment, as described above, the relay lens 3
Since the position along the optical axis direction of 30 can be adjusted by the stage 360, the size of the illumination area of the B light can be adjusted. Thereby, the illumination efficiency of the illumination light for illuminating the B light valve 400B can be improved.

The color temperature of the projected image can be adjusted by positively changing the illumination efficiency of the illumination light. Particularly, as in the present embodiment, the relay optical system 300
When the light passing through is the B light, it is easy to adjust the color temperature.

Therefore, B passing through the relay optical system 330
Adjustment can be easily performed to match the illumination area of light with the illumination area of illumination light of another color.

In the above embodiment, the relay lens 33
Although the case where the position of 0 is adjusted along the optical axis direction is described as an example, the position of the incident side lens 310 may be adjusted along the optical axis direction. However, in this case, the change in the incident angle of the illumination light that illuminates the B light valve 400B becomes larger than when the position of the relay lens 330 is adjusted. Changes in the angle of incidence of light may affect the performance of other optical systems. For example, a change in the angle of incidence on the light valve may result in a change in the modulation characteristics of the light. Therefore, it is not preferable to adjust only the size of the illumination area. Considering this point, it is more advantageous to adjust the position of the relay lens 330.
Further, in the above-described embodiment, the case where the position of one of the three lenses included in the relay optical system 330 is adjusted is described as an example. However, the present invention is not limited to this.
The position of at least one of the lenses constituting the relay optical system may be adjustable in the optical axis direction. Such a modification can be similarly applied to the relay optical systems of the following embodiments.

B. Second Embodiment FIG. 4 is a schematic plan view showing a main part of an optical system of a projector as a second embodiment of the present invention. This projector PJ2 has an illumination optical system 1
00, a color light separation optical system 200A, two relay optical systems 300 and 700, and three light valves 400R and 400R.
00G, 400B and cross dichroic prism 5
00 and a projection lens 600. Each component is arranged substantially horizontally around the cross dichroic prism 500. The same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted.

The color light separation optical system 200A is composed of a cross dichroic mirror in which two dichroic mirrors 202 and 204 are arranged in a substantially X shape. The first dichroic mirror 202 reflects the R light,
G light and B light are transmitted. The second dichroic mirror 204 reflects the B light and transmits the G light and the R light. Thus, the color light separation optical system 200A converts the illumination light emitted from the illumination optical system 100 into R, G, and B lights.
Light into two colors.

G emitted from the color light separation optical system 200A
The light passes through the field lens 250 and enters the G light valve 400G. The B light passes through the first relay optical system 300 and illuminates the B light valve 400B. The R light passes through the second relay optical system 700,
The R light valve 400R is illuminated.

The second relay optical system 700 includes, similarly to the first relay optical system 300, an incident side lens 710 and a first relay optical system 700.
, A relay lens 730, a second reflection mirror 740, and an emission-side lens (field lens) 750. Second relay optical system 700
The first relay optical system 3 for R light and B light
It has the same function as 00.

The second relay lens 730, like the first relay lens 330, is mounted on a stage (not shown) whose position in the optical axis direction can be adjusted. Therefore, by adjusting the position of the relay lens 730 in the optical axis direction, the size of the illumination area for illuminating the R light valve 400R can be adjusted. Thereby, the illumination efficiency of the illumination light for illuminating the R light valve 400R can be improved. Also, the color temperature of the projected image can be adjusted by positively changing the illumination efficiency of the illumination light.

As described above, in this embodiment, in addition to the B light valve 400B, the R light valve 4B is used.
The size of the illumination area of the illumination light for illuminating 00R can also be independently adjusted.

Here, the G light valve 4
It is assumed that the size of the illumination area of the illumination light for illuminating 00G is set as a reference. At this time, the illumination areas of the R and B light valves 400R and 400B can be independently adjusted by adjusting the positions of the corresponding relay lenses 730 and 330, respectively. Valve 400R, 400G, 400
The size of the illumination area B can be set optimally. This makes it possible to further improve the illumination efficiency of the entire projector as compared with the first embodiment.
Further, the range of color temperature adjustment can be improved.

As described above, the second embodiment is different from the first embodiment.
As compared with the embodiment, the adjustment for matching the illumination regions of the illumination lights of three colors can be further facilitated.

C. Modifications: The present invention is not limited to the above-described examples and embodiments, and can be carried out in various modes without departing from the gist thereof. For example, the following modifications are also possible. is there.

(1) In the first embodiment, the stage 360 is used as a device for adjusting the position of the relay lens 330.
However, the present invention is not limited to this. For example, a configuration in which a plurality of slots for disposing the relay lens 330 are provided and the position of the slot for disposing the relay lens 330 is changed to adjust the position in the optical axis direction may be employed. That is, any device may be used as long as the position of the relay lens 330 can be adjusted in the optical axis direction. The same applies to the stage for adjusting the position of the relay lens 730 in the second embodiment.

(2) In the first embodiment, the stage 360 for adjusting the position of the relay lens 330 is a device for adjusting the position in the optical axis direction. However, the present invention is not limited to this. Alternatively, a three-dimensional stage that can adjust the positions in two axial directions perpendicular to each other may be used. This makes it possible to adjust the position of the illumination area on the light incident surface of the light valve. The same applies to the stage for adjusting the position of the relay lens 730 in the second embodiment.

(3) In the first embodiment, the case where the illumination light of the color passing through the relay optical system 300 is the B light is described as an example, but another color light may be used. In the second embodiment, the R light and the B light are two relay optical systems 300 and 7.
Although the case of passing through 00 is described as an example, the present invention is not limited to this, and a combination of other color lights may be used.

(4) In each of the above embodiments, a projector having three light valves (electro-optical devices) has been described as an example, but the present invention is also applicable to a projector having two light valves. That is, the present invention is applicable to a projector including a plurality of light valves.

(5) In each of the embodiments described above, the projector using a transmissive liquid crystal panel as a light valve is described as an example. However, the present invention is similarly applied to a projector using a reflective liquid crystal panel. Applicable. Further, a digital micromirror device (trademark of TI) may be used as the reflection type light valve instead of the reflection type liquid crystal panel.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a main part of an optical system of a projector as a first embodiment of the invention.

FIG. 2 is an explanatory diagram showing a relay lens 330 in an enlarged manner.

FIG. 3 is an explanatory diagram showing a relationship between a position of a relay lens 330 and an illumination area of illumination light for illuminating a B light valve 400B.

FIG. 4 is a schematic plan view showing a main part of an optical system of a projector as a second embodiment of the invention.

[Explanation of symbols]

 Reference Signs List 100 illumination optical system 110 light source 120 first lens array 130 second lens array 140 polarization conversion element 150 superimposing lens 200 color light separation optical system 210 first dichroic mirror 220 second dichroic Mirror 230 ... Reflection mirror 200A ... Color light separation optical system 202 ... First dichroic mirror 204 ... Second dichroic mirror 240 ... Field lens 250 ... Field lens 300 ... Relay optical system 310 ... Incoming lens 320,340 ... Mirror 330 ... Relay lens 350 ... Ejection side lens (field lens) 360 ... Stage 361 ... Base 362 ... Holder 363 ... Table 364 ... Guide rail 365 ... Screw groove 365 ... Bolt 400R, 400G, 400B ... Light valve 500 ... Loss dichroic prism 510R, 510G dichroic surface 600 projection lens 700 relay optical system 710 incident lens 720, 740 reflection mirror 730 relay lens 750 emission lens (field lens) PJ1 projector PJ2 projector LI Light incidence surface LA: illumination area LB: illumination area LC: illumination area

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03B 21/14 G03B 21/14 D 33/12 33/12 H04N 9/31 H04N 9/31 CF term ( (Reference) 2H088 EA14 EA15 EA19 HA13 HA24 HA25 HA28 MA05 2H091 FA05X FA05Z FA26X FA26Z FA29Z FA41Z FD01 FD24 LA15 LA16 MA07 5C060 GB02 GB06 GD07 HC01 HC21 HC25 JA16 JA18 JB06

Claims (4)

[Claims] 1. A projector for projecting an image, comprising: an illumination optical system; a color light separation optical system that separates illumination light emitted from the illumination optical system into a plurality of colors of illumination light; A plurality of electro-optical devices for converting light into light corresponding to the corresponding color signals; and a light representing a color image by combining converted lights of a plurality of colors emitted from the plurality of electro-optical devices. A color light combining optical system, and a projection optical system that projects a color image represented by the combined light emitted from the color light combining optical system, further comprising: a plurality of colors of illumination light emitted from the color light separating optical system. A relay optical system is provided in the path of the illumination light of at least one color, and the relay optical system adjusts a position of at least one lens among a plurality of lenses included in the relay optical system along an optical axis direction. Adjustment equipment The having, projector. 2. The projector according to claim 1, wherein the color light separation optical system separates the illumination light emitted from the illumination optical system into three colors of illumination light, and emits the light from the color light separation optical system. A relay optical system in the path of the illumination light of two colors among the three colors of illumination light obtained, wherein each of the relay optical systems is at least one of a plurality of lenses included in each relay optical system. A projector having an adjusting device for adjusting a position of a lens along an optical axis direction. 3. The projector according to claim 1, wherein the at least one lens includes a relay lens. 4. The projector according to claim 1, wherein the adjustment device is further capable of adjusting positions in two axial directions perpendicular to the optical axis direction and perpendicular to each other. .