JPH09230301A - Projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection type display device of two-plate system excellent in color purity and forming a bright projected image in comparison with the conventional projection type display device of two-plate system. SOLUTION: In This display device 100, P polarized light and S polarized light separated by a polarizing beam splitter 3 are made incident on a 1st liquid crystal panel 62 provided with the color filter layers of RGB and a 2nd liquid crystal panel 61 provided with the color filter layers of CMY being the complementary colors of RGB, respectively. The color images formed through the panels 62 and 61 are composed through a polarizing beam splitter 9 and enlarged and projected on a projection surface 11 through a projection lens optical system 10. By using two panels 61 and 62, the luminance of the projected picture is secured and color reproducibility is secured, so that the color purity becomes high and the bright projected image is obtained in comparison with the conventional projection type display device of twoplate system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type display device which modulates a light flux from a light source according to image information by a light modulating means such as a liquid crystal panel and projects the modulated light flux on a projection surface. Yes, more specifically, it relates to a projection type display device provided with two sets of light modulating means.

[0002]

2. Description of the Related Art Various types of projection type display devices for projecting and displaying a color image using a liquid crystal panel as a light modulating means are known. Of these, the most popular one is the three-panel system using three liquid crystal panels.
This is a projection display device of a type called a single plate type using one liquid crystal panel.

FIG. 7 shows a schematic structure of an optical system of a commonly used three-plate type projection type liquid crystal display device. In this figure, reference numeral 1 is a light source lamp, and the light from this is reflected by a reflection mirror 2 to be a parallel light flux, which is emitted to the color separation optical system 11 side. Color separation optical system 1
1 includes dichroic mirrors 111 and 112 and a mirror 113. The dichroic mirror 111 is
The red light flux R is transmitted, but the green and blue light fluxes G and B are reflected, and the other dichroic mirror 112 is used.
Reflects the green luminous flux G but transmits the blue luminous flux B. These two dichroic mirrors 111,
The white light flux W is separated by 112 into red, green, and blue color light fluxes R, G, and B.

The separated light beams of the respective colors pass through the incident side polarization plates 53, 54 and 55 to become linearly polarized lights, and then enter the three liquid crystal panels 63, 64 and 65 corresponding to the respective colors. Each of the liquid crystal panels 63, 64, and 65 has a configuration in which the emission side polarization plates 73, 74, and 75 are attached to their emission surfaces in an optically closely attached state. These liquid crystal panels 63, 64, 65 modulate the incident light flux based on the given image information. The modulated light fluxes R, G, and B of the respective colors pass through the emission side polarization plates 73, 74, and 75, respectively, and then are dichroic mirrors 121 and 12.
2 and the color combining optical system 12 including the mirror 123, and are combined into one modulated light beam. The combined modulated light flux is enlarged and projected onto a projection surface 13 such as a screen via a projection lens optical system 10. As the color synthesizing optical system, a structure using a prism optical system using a dichroic prism instead of the dichroic mirror is also known.

The three-panel type projection display device has an advantage that a high-quality image having high brightness and high resolution can be obtained because the light utilization efficiency is high. On the other hand, since the three liquid crystal panels are driven, the circuit system and the optical system become complicated, and the number of parts constituting the projection type display device inevitably increases. As a result, there are drawbacks that the outer shape and weight of the projection type display device become large and the manufacturing cost also rises.

FIG. 8 shows a schematic structure of an optical system of a commonly used single-plate type projection display device, and parts corresponding to respective parts in FIG. There is. As shown in this figure, the white light beam W emitted from the light source lamp 1 and reflected by the reflection mirror 2 as a parallel light beam is transmitted through the incident side polarization plate 56 to become linearly polarized light, and then red, green, blue ( The light enters the liquid crystal panel 66 including the R, G, and B) color filters. An emission side polarization plate 76 is attached to the emission surface of the liquid crystal panel 66 in a state of being in close optical contact. The liquid crystal panel 66 modulates the incident light flux based on the given image information. The modulated light flux passes through the emission side polarization plate 76 and then is enlarged and projected on the screen 13 via the projection lens optical system 10.

Contrary to the above-mentioned three-panel projection-type display device, the single-panel projection-type display device has advantages that it can realize a projection-type liquid crystal display device having a small number of parts, a small size and a light weight. Since the liquid crystal panel is equipped with R, G, and B color filters, about two-thirds of the amount of light incident on the liquid crystal panel is absorbed by the color filters and the remaining three.
Only one-third is available. For this reason, there is a drawback in that the image projected by the projection display device becomes dark. In order to solve this drawback, a larger amount of light may be incident on the liquid crystal panel, but this causes new adverse effects such as heat generation and increase in power consumption.

On the other hand, as a projection type display device, a two-plate type projection type display device having intermediate characteristics of the above-mentioned three-plate type and single-plate type is also known. FIG. 9 shows a schematic configuration of an optical system of a projection type display device of this type, and in this figure as well, parts corresponding to the parts in FIG. 7 and FIG. There is. As shown in this figure, the light beam from the light source lamp 1 enters the polarization beam splitter 3 via the reflection mirror 2 and is separated into a P-polarized light beam and an S-polarized light beam whose polarization axes are substantially orthogonal to each other.

The P-polarized light beam passes through the incident side polarization plate 58 and enters the brightness ensuring liquid crystal panel 68. LCD panel 6
An output side polarization plate 78 is attached to the output surface in a state in which the output side polarization plate 78 is in close optical contact with each other, and the incident light flux is modulated corresponding to given image information. The light beam that has passed through the emission side polarization plate 78 is reflected by the reflection mirror 8 and is incident on the polarization beam splitter 9.
It should be noted that the incident-side polarization plate may be omitted if the polarized light beam of the polarization beam splitter 3 is linearly polarized light, but in reality, it is not linearly polarized light to obtain a sufficient contrast ratio. A configuration in which an incident side polarization plate is arranged is generally adopted.

On the other hand, the S-polarized light beam passes through the incident side polarization plate 57 through the mirror 4 and enters the liquid crystal panel 67 having the R, G and B color filters. The liquid crystal panel 67 has a structure in which an emission side polarization plate 77 is attached to its emission surface in an optically closely attached state, and modulates an incident light flux based on given image information.

2 emitted from each liquid crystal panel 67, 68
The two modulated light beams are combined into one modulated light beam by the polarization beam splitter 9 and then enlarged and projected on the screen 13 via the projection lens optical system 10.

A reflective liquid crystal panel is used to
An example of a plate-type projection display device is disclosed in, for example, Japanese Patent Application Laid-Open No. 3-139638.

[0013]

In the two-panel type projection display device having such a structure, the S-polarized light beam is incident on the liquid crystal panel having R, G, B color filters for color display. , P-polarized light flux is incident on the monochrome display panel for ensuring the brightness. Further, the light from the light source is split into a P-polarized light beam and an S-polarized light beam by a polarization beam splitter, and the light beams in the respective polarization directions are made incident on a liquid crystal panel having a polarizing plate with a polarization axis matching them. The amount of light absorbed by the side polarizing plate is reduced as much as possible to improve the light utilization efficiency. Moreover, since the number of parts is smaller than that of the three-plate type, it is possible to realize a projection type display device that is small and lightweight, inexpensive, and capable of obtaining bright display.

However, in the two-plate type projection display device, of the two liquid crystal panels, only the liquid crystal panel having the R, G and B color filters contributes to the color display. Therefore, the color purity of the projected image is the same as that of the single-panel projection display device. Therefore, it is possible to increase the utilization efficiency of the amount of light from the light source to increase the brightness of the projected image by using the other brightness securing liquid crystal panel, but when attempting to secure a certain level of color purity, It is necessary to greatly reduce the light intensity of the brightness image. In other words, it is the current situation that the advantage of arranging the brightness securing liquid crystal panel cannot be effectively utilized, and therefore, in the conventional two-panel projection type liquid crystal display device, it is actually as expected. A projected image with brightness has not been obtained.

In view of the above points, an object of the present invention is to propose a two-panel type projection display device capable of increasing the brightness while ensuring the color purity of a projected image.

[0016]

In order to solve the above-mentioned problems, a projection type display device of the present invention is a first color filter layer which modulates a first polarized light beam and transmits only a predetermined color light. And a second light modulator having a polarization axis substantially orthogonal to the polarization axis of the first polarized light beam.
And a second light modulating means including a second color filter layer that modulates the polarized light flux and that transmits only the color light that has a complementary color relationship to the color light that passes through the first color filter layer, A configuration having projection optical means for projecting a combined image obtained by combining the modulated light fluxes emitted from the first and second light modulating means is adopted.

In the projection type display device having this structure, the brightness of the projected image and the color reproducibility are ensured by using both of the two sets of light modulating means. Therefore, the color purity is higher than that of the conventional two-panel projection display device,
Moreover, a bright projected image can be obtained.

In a typical configuration of the present invention, the first color filter layer has a red light transmission region that transmits only red light, a green light transmission region that transmits only green light, and only blue light. It has a blue light transmission area that
Similarly, the second color filter layer has a cyan light transmission region that transmits only cyan light, a magenta light transmission region that transmits only magenta light, and a yellow light transmission region that transmits only yellow light.

In this case, the color light transmitted through each of the red light transmitting region, the green light transmitting region and the blue light transmitting region is transmitted through each of the cyan light transmitting region, the magenta light transmitting region and the yellow light transmitting region. With colored light,
A configuration may be adopted in which these regions are formed in the first and second color filter layers so that they overlap each other on the composite image.

In addition to the above-mentioned structure, the projection type display device further includes a light source, a polarization separating means for separating a light beam emitted from the light source into the first polarized light beam and the second polarized light beam, and the first and second polarized light beams. A configuration having a light combining means for combining the modulated light fluxes emitted from the first and second light modulating means is adopted.

Here, as the first and second light modulating means, not only a light transmitting type but also a light reflecting type can be used.

When a light reflection type light modulating means is used,
The polarized light separating means and the light combining means can be constituted by a common polarizing beam splitter made of a prism combined body. That is, the light source, the first and second reflection-type light modulation means, and the projection means may be arranged to face each other on the four outer surfaces of the polarization beam splitter. In the optical system having this configuration, the light emitted from the light source is first separated into the S-polarized light flux and the P-polarized light flux by the polarization beam splitter, and the respective light fluxes are arranged in the separation direction. The light is incident on the light modulation means and is modulated according to the image information, and only the predetermined color light is converted through the color filter layer in the direction in which the polarization axes are orthogonal to each other, or is the polarization axis that is incident. It is reflected in a controlled state. The modulated light beams output from the respective reflection-type light modulation means are again incident on the polarization beam splitter, combined, and then emitted toward the projection means, and enlarged and projected on the projection surface via the projection means. .

When the reflection type light modulating means is used as described above, the polarization separating means and the light combining means can be constructed by using a common optical element, so that the optical system can be simplified.

Next, the red light transmissive region, the green light transmissive region and the blue light transmissive region may be assigned to each pixel forming the first light modulating means in a fixed pattern, Similarly, the cyan light transmissive region, the magenta light transmissive region, and the yellow light transmissive region may be assigned to each pixel forming the second light modulator in a fixed pattern.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the main configuration of an optical system of a two-plate projection type display device to which the present invention is applied.
Portions corresponding to the respective portions in FIGS. 7 to 9 are designated by the same reference numerals.

As shown in this figure, in the two-panel projection type display device 100, the light from the light source lamp 1 is reflected by the reflection mirror 2.
A white parallel light beam W is made incident on the polarization beam splitter 3 which is a polarization separation means, and is separated into a P polarization light beam and an S polarization light beam. The P-polarized light flux is incident on the incident side polarization plate 52.
And is incident on the first liquid crystal panel 62 as the first light modulating means including the red (R), green (G) and blue (B) color filter layers. The first liquid crystal panel 62 is
The exit-side polarization plate 72 is attached to the exit surface in a state of being in optical contact, and the incident P-polarized light flux is modulated based on the given image information.

On the other hand, the S-polarized light beam passes through the incident side polarization plate 51 through the mirror 4 and is provided with a second color filter layer of cyan (C), yellow (Y) and magenta (M). The light enters the second liquid crystal panel 61 as the light modulating means. The second liquid crystal panel 61 has a structure in which an exit-side polarization plate 71 is attached to the exit surface thereof in a state of being in close optical contact with each other. It modulates it.

The modulated light beams emitted from the first and second liquid crystal panels 62 and 61 are combined into one modulated light beam by the polarization beam splitter 9 as a light combining means to form a combined image. This composite image is enlarged and projected onto a projection surface 13 such as a screen via a projection lens optical system 10 which is a projection optical unit. In addition, the S on the side of the first liquid crystal panel 62.
The optical system may be configured so that the polarized light beam is incident and the P-polarized light beam is incident on the second liquid crystal panel 61 side. The incident side polarization plates 51 and 52 are the polarization beam splitter 3
It does not need to be provided as long as it has good polarization separation characteristics.

Next, referring to FIG. 2, the arrangement state of each color of the color filter layers in the first and second liquid crystal panels 62 and 61, and these two liquid crystal panels 6 will be described.
The image combined by 1 and 62 will be described.

FIG. 2A shows the first liquid crystal panel 62 of the first liquid crystal panel 62.
The arrangement state of each color in the color filter layer of is shown. In this first color filter layer 620, a red light transmission region R that transmits only red light, a green light transmission region G that transmits only green light, and a blue light transmission region B that transmits only blue light are The liquid crystal panel 62 is formed at a position corresponding to each pixel. In this example, the regions R, G, and B are repeatedly formed in this order in the row direction of the pixel array. It should be noted that the arrangement form of the regions R, G, and B is not limited to the arrangement state of this example as long as the appearance frequency and the density of the regions are substantially the same.

On the other hand, as shown in FIG.
Second color filter layer 610 of second liquid crystal panel 61
In the arrangement of the respective colors, the cyan light transmission region C that transmits only cyan light, the magenta light transmission region M that transmits only magenta light, and the yellow light only are arranged at positions corresponding to the respective images of the second liquid crystal panel 61. A yellow light transmitting region Y for transmitting the light is formed. Further, the array of these regions C, M, Y is also a state in which the regions C, M, Y are repeated in this order in the row direction of the pixel array. In addition to this, the region R of the first color filter layer,
Regions C, M and Y having a complementary color relationship with G and B are arranged at corresponding positions. That is, on the composite image obtained via the polarization beam splitter 9, the second liquid crystal panel 61 is irradiated with the red light which is transmitted through the region R of the first color filter layer of the first liquid crystal panel 62. The second color filter layer has an arrangement relationship in which the irradiation areas of the cyan light transmitted through the area C having a complementary color relationship overlap each other. Similarly, on the combined image obtained via the polarization beam splitter 9, the first liquid crystal panel 62
Of the green and blue light beams that have passed through the color filter layer regions G and B, and magenta that has passed through the complementary color regions M and Y of the second color filter layer of the second liquid crystal panel 61, The arrangement relationship is such that the irradiation areas of the respective yellow light rays are overlapped.

Therefore, the arrangement relationship of the regions R, G, B of the first color filter layer shown in FIG. 2A is an image obtained when all the pixels of the first liquid crystal panel 62 are in the display state. Similarly, the arrangement relationship of the regions C, M, and Y of the second color filter layer shown in FIG. 2B is similar to the case where all the pixels of the second liquid crystal panel 61 are in the display state. It represents the resulting image. As a result, the composite image obtained by combining these images, that is, the composite image obtained through the polarization beam splitter 9 is as shown in FIG.
As shown in (C), in each pixel area, colored lights having a complementary color relationship are superimposed on each other to become a white display area W. Note that although the mosaic type color array is described in FIG. 2, the present invention is not limited to this, and a stripe type, delta type, or other color array may be used.

Next, the operation for color display will be described. For example, when displaying red, the pixels of the red light transmission region R of the first liquid crystal panel 62 are displayed, and the pixels of the yellow transmission region Y and the magenta transmission region M are displayed on the second liquid crystal panel 61 side. Let That is, in the case of the first and second liquid crystal panels 62 and 61 shown in FIG.
The unit pixel of the projection image is displayed by the three pixels arranged in the row direction. Therefore, when red is displayed on the unit pixel U of the projection image as shown in FIG. 3C, the first pixel corresponding to the unit pixel U is displayed as shown in FIG. Three pixel regions 6 in the liquid crystal panel 62
Only the R area 62-1 in 2-1 to 62-3 is displayed. On the other hand, as shown in FIG. 3B, on the side of the three pixel regions 61-1 to 61-3 in the second liquid crystal panel 61 corresponding to the unit pixel U, a red component is generated. The areas M and Y that it has are displayed.

In the portion of the unit pixel U of the composite image of FIG. 3C thus obtained, the relationship between the light amount and the wavelength of the portion is schematically represented by the graph of FIG. 4A. It becomes a state. As shown in this graph, the amount of light in the red wavelength band is the sum of the amount of light that has passed through the region R of the first liquid crystal panel 62 and the amount of light that has passed through the regions M and Y of the second liquid crystal panel 61. . Therefore, red display is performed with a color purity of a light amount three times the luminance of the unit pixel U.

On the other hand, in the conventional two-plate type projection display device shown in FIG. 9, the liquid crystal panel 67 is for color display, and the light amount of each color obtained through this is 1 of the light source light amount.
/ 6, and the amount of light obtained through the other brightness securing liquid crystal panel 68 is ½ of the amount of light from the light source. Therefore, for example, when the red display is performed, the relationship between the overall luminance and the color purity in the unit pixel U of the combined image is as shown in FIG. As can be seen by comparing the graphs of FIGS. 4A and 4B, in the projection display device according to the present invention, although the overall brightness of the projected image is reduced, it is possible to display with high color purity.

Here, as described above, in the conventional two-panel projection display device, in order to ensure the color purity, the light amount of the black and white image obtained via the luminance ensuring liquid crystal panel is reduced. In order to secure the same color purity as that of the projection type display device according to the present invention, it is necessary to reduce the light quantity of a monochrome image obtained through the brightness securing liquid crystal panel to at least 1/3 or less. The obtained composite image has extremely low brightness. However, according to the projection display device of the present invention, it is possible to form a bright projection image while ensuring color purity. In the above description, the display method of the first and second liquid crystal panels in the red display has been described. However, in the case of the green display, the pixel area 62-2 and the pixel area 61-2 are displayed.
Display 1, 61-3. In the case of blue display, the pixel area 61-3 and the pixel areas 61-1 and 61-2 are displayed.
A similar effect can be obtained by displaying.

FIG. 5 shows a graph of the color reproduction range of the projection type display device 100 according to the present invention. In this graph, a region P1 indicated by a broken line is the color reproduction range of the first liquid crystal panel including the RGB color filter layer. A region P2 shown by a one-dot chain line is a color reproduction range of the second liquid crystal panel including the CMY color filter layer. Further, a region (P1 + P2) indicated by a thick solid line is a color reproduction range in the case where the maximum amount of light is obtained in a combined image by the two liquid crystal panels. Although the color purity decreases when the maximum light amount is displayed, it is possible to display the brightness three times as high as that of the conventional single-panel projection display device. Also, CYM
By suppressing the amount of light of the image obtained by passing through the second liquid crystal panel having the color filter layer, the color image obtained through the first liquid crystal panel having the RGB color filter layer has high color purity. A projected image can be obtained, and brightness and color purity can be arbitrarily adjusted as needed.

Next, FIG. 6 is a schematic configuration diagram showing an optical system of another embodiment of a two-plate type projection display device to which the present invention is applied. In the example shown in this figure, a reflective liquid crystal panel is used as the first and second liquid crystal panels.
In the projection type display device 200 of this example, the light emitted from the light source lamp 1 is reflected by the reflection mirror 2 and becomes a parallel light flux W, which is incident on the polarization beam splitter 3 which functions as a polarization separating means. The polarization beam splitter 3 has a quadrangular prism shape made of a prism composite body in which two prisms are stuck together, and the sticking surface thereof is a polarization separation film 30 made up of a multilayer dielectric film. The parallel light beam W from the light source lamp 1 side is incident at a right angle from the outer surface 31 of the polarization beam splitter 3, and in the polarization separation film 30, only the P-polarized light is transmitted and the S-polarized light is reflected. A first reflection type liquid crystal panel 62A is arranged to face the outer surface 33 of the polarization beam splitter 3 on the P polarized light transmission side. Further, a second reflective liquid crystal panel 61A is arranged to face the outer surface 32 of the polarization beam splitter 3 on the reflection side of S-polarized light. Next, the operation will be described, but the following description will be made on the assumption that the liquid crystal of the reflective liquid crystal panel is vertically aligned.

The first reflective liquid crystal panel 62A has RGB
It is composed of a liquid crystal cell 62a having a color filter layer and a total reflection mirror 62b arranged on the back surface thereof. Then, at the positions corresponding to the respective pixels of the liquid crystal cell, the transmissive regions R, G, B of the respective colors are formed in the same array state as described with reference to FIG. The P-polarized light that has entered the first reflective liquid crystal panel 62A having this configuration has its polarization direction rotated by 45 degrees while passing through the pixel area in the driving state of the liquid crystal cell 62a, and then the total reflection mirror 62b. While being reflected and again passing through the pixel area in the driven state, the polarization direction is rotated again by 45 degrees.
As a result, the P incident on the first reflective liquid crystal panel 62A is
The polarized light becomes S-polarized light and is emitted from the first reflective liquid crystal panel 62A. On the other hand, when passing through the pixel region that is not in the driving state, the incident P-polarized light is directly emitted as P-polarized light. Since the principle of the reflective liquid crystal panel is well known, its description is omitted here.

Similarly, secondly, the reflection type liquid crystal panel 61A.
Is a liquid crystal cell 61a having a CMY color filter layer.
And a total reflection mirror 61b arranged on the back surface thereof. Then, at the positions corresponding to the respective pixels of the liquid crystal cell, the transmissive regions C, M and Y of respective colors are formed in the same array state as described with reference to FIG. The S-polarized light that has entered the second reflective liquid crystal panel 61A having this configuration has its polarization direction rotated by 45 degrees while passing through the pixel region in the driving state of the liquid crystal cell 61a, and then the total reflection mirror 61b. While being reflected and again passing through the same pixel area in the driven state, the polarization direction is rotated again by 45 degrees. As a result, the first reflective liquid crystal panel 61
The S-polarized light that has entered A becomes P-polarized light and exits from the second reflective liquid crystal panel 61A. On the other hand, when passing through the pixel region which is not in the driving state, the incident S-polarized light is directly emitted as S-polarized light.

The P-polarized light and the S-polarized light thus emitted from the liquid crystal panels 61A and 62A again enter the polarization beam splitter 3, are combined via the polarization separation film 30, and are emitted at their emission surfaces. It is emitted from a certain side surface 34 as a combined image light flux. That is, of the light flux emitted from the liquid crystal panel 62A, the S-polarized component of each pixel area is reflected toward the projection lens system 10 side, and of the light flux emitted from the liquid crystal panel 62B, the P-polarized component of each pixel area is projected. Lens 1
Transmits to the 0 side. As a result, a composite image is formed by the components of the light emitted to the outer surface 34 of the polarization beam splitter. Therefore, the polarization beam splitter 3 is a common optical element that functions as a polarization separating means and also as a light combining means. Light emitted from the polarization beam splitter 3 is enlarged and projected onto a projection surface 13 such as a screen via a projection optical system 10 which is a projection means.

As described above, the reflection type liquid crystal panel is used.
Also in the plate-type projection display device 100, it is possible to obtain the same effects as those of the above-mentioned projection display device 100.
In addition to this, when using a reflective liquid crystal panel,
There is also an advantage that the optical system can be made small and compact. The reflective liquid crystal panel described above has a configuration in which a total reflection mirror is arranged on the back surface of the liquid crystal cell.
As the reflective liquid crystal panel, there is one having a structure in which the pixel electrode itself is formed of a metal such as aluminum and the incident light is reflected by the pixel electrode itself. The effect can be obtained.

On the other hand, in each of the above embodiments, the liquid crystal panel controls the rotation angle of the polarization axis of the incident polarized light based on the image information. However, in the present invention, the light modulating means is not limited to this. However, various light valves such as PLZT and mirror type light valves can be used as the light modulating means.

[0044]

As described above, in the projection type display device of the present invention, the first light modulating means having the first color filter layer and the second light modulating means having the second color filter layer are provided. A modulation means, and the colors of corresponding regions of the first and second color filter layers are set so as to have a complementary color relationship with each other. Therefore, by driving the corresponding regions of both the light modulation means, it is possible to perform white display in which complementary colors are superimposed. Further, it is possible to display each color by utilizing the color light flux obtained through both the light modulation means. As described above, since the brightness and the color purity of the projected image can be adjusted by using both the light modulators, the color purity is higher and the bright projected image is formed as compared with the conventional two-plate type projection display device. can do.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an optical system of a two-plate type projection display device to which the present invention is applied.

2A to 2C are explanatory views showing a color image formed by the first liquid crystal panel in the projection display apparatus of FIG. 1, and a color image formed by the second liquid crystal panel, respectively. 3A and 3B are explanatory diagrams showing a composite image of these color images.

3A to 3C are explanatory views of a color image formed by three pixels of the first liquid crystal panel in the projection display apparatus of FIG. 1, and correspond to the second liquid crystal panel, respectively. It is explanatory drawing of the color image formed by three pixels, and explanatory drawing of the composite image of these color images.

4A is a graph conceptually showing the relationship between the wavelength and the light amount of the composite image obtained by the projection display device of FIG. 1, and FIG. 4B is a composite image obtained by the conventional two-panel projection display device. It is a graph which shows notionally the relationship of the light quantity with respect to the wavelength of an image.

5 is a graph showing a color reproduction range of the projection type display device of FIG.

FIG. 6 is a schematic configuration diagram showing an optical system of a projection type display device including a reflection type liquid crystal panel to which the present invention is applied.

FIG. 7 is a schematic configuration diagram showing an optical system of a conventional three-panel projection type display device.

FIG. 8 is a schematic configuration diagram showing an optical system of a conventional single-panel projection type display device.

FIG. 9 is a schematic configuration diagram showing an optical system of a conventional two-panel projection type display device.

[Explanation of symbols]

 1 Light Source Lamp 2 Reflecting Mirror 3 Polarizing Beam Splitter 4 Mirror 61 Second Liquid Crystal Panel 62 First Liquid Crystal Panel 61A Second Reflecting Liquid Crystal Panel 62A First Reflecting Liquid Crystal Panel 9 Polarizing Beam Splitter 10 Projection Lens Optical System 13 Projection surface 100, 200 Projection type display device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G03B 21/00 G03B 21/00 D H04N 9/31 H04N 9/31 C

Claims (8)

[Claims] 1. A first light modulating means for modulating a first polarized light beam and having a first color filter layer for transmitting only predetermined color light; and a polarization axis of the first polarized light beam. A second color filter layer that modulates a second polarized light flux having polarization axes that are substantially orthogonal to each other and that transmits only color light that has a complementary color relationship with the color light that passes through the first color filter layer is provided. And a second optical modulation means, and projection optical means for projecting a combined image obtained by combining the modulated light fluxes emitted from the first and second light modulation means. apparatus. 2. The first color filter layer according to claim 1, wherein the first color filter layer transmits a red light only, a red light transmitting region, a green light only transmitting region, and a blue light only transmitting blue light. The second color filter layer has a transparent region, a cyan light transmitting region that transmits only cyan light, a magenta light transmitting region that transmits only magenta light, and a yellow light transmitting region that transmits only yellow light. A projection display device characterized by being provided. 3. The color light transmitted through each of the red light transmissive region, the green light transmissive region, and the blue light transmissive region according to claim 2, wherein the cyan light transmissive region, the magenta light transmissive region, and the yellow light transmissive region. These areas are formed in the first and second color filter layers so that the color light transmitted through each of them overlaps on the composite image. 4. The light source and the light flux emitted from the light source according to any one of claims 1 to 3,
Of the polarized light flux and the second polarized light flux, and a light synthesizing means for synthesizing the modulated light fluxes emitted from the first and second light modulating means. apparatus. 5. The projection type display device according to claim 1, wherein the first and second light modulating means are transmission type light modulating means. 6. The projection type display device according to claim 1, wherein the first and second light modulators are reflection light modulators. 7. The polarized light splitting means and the light combining means according to claim 6, wherein the polarized light separating means and the light combining means are shared polarizing beam splitters, and the light source and the light source are respectively provided on four outer surfaces of the polarizing beam splitter. A projection type display device characterized in that first and second reflection type light modulating means and the projection optical means are arranged to face each other. 8. The red light transmissive region, the green light transmissive region, and the blue light transmissive region according to any one of claims 5 to 7, with respect to each pixel of the first light modulator. The cyan light transmission region, the magenta light transmission region, and the yellow light transmission region are assigned in a fixed pattern and are assigned in a fixed pattern to each pixel of the second light modulator. Characteristic projection display device.