JP2823722B2 - Polarization combining element and liquid crystal display device using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarization synthesizing element capable of producing linearly polarized light from indefinitely polarized light and improving the use efficiency of light from a light source, and a liquid crystal display device using the same. is there.

[0002]

2. Description of the Related Art Conventionally, as a device utilizing linearly polarized light, a typical one is a TN liquid crystal display device, and a liquid crystal display device using this as a liquid crystal light valve is disclosed in, for example, JP-A-63-15225. No. or JP-A-63
As described in JP-A-116123, white light output from a single light source is converted into red, white light by a dichroic mirror.
The light is separated into three primary colors of blue and green, and the three primary colors are respectively incident on three liquid crystal light valves to obtain images corresponding to the three primary colors, and these images are obtained using a dichroic mirror or a dichroic prism. In some cases, a color image is obtained by combining the images, and the color image is enlarged and projected on a screen using a single projection lens.

[0003]

In the above prior art, the liquid crystal display element used as the liquid crystal light valve has both ends formed of polarizing plates, whereby the light incident on the liquid crystal display element is p-polarized. Only one of light or S-polarized light is emitted. That is,
The amount of light transmitted through the liquid crystal display element, that is, the light utilization efficiency is reduced by half, and considerable light loss occurs.

Here, P-polarized light refers to linearly polarized light having a plane of polarization parallel to the plane of incidence (the plane on which the electric vector oscillates), and S-polarized light refers to the plane of polarization relative to the plane of incidence. It refers to linearly polarized light having a perpendicular polarization plane.

For example, conventionally, a polarizing plate having a dye (a dichroic dye) is generally used as the polarizing plate.
In that case, an element that transmits the P-polarized light absorbs the S-polarized light, resulting in light loss.

In the prior art, it has been pointed out that there is a problem in the aperture ratio of the liquid crystal display element. Here, the aperture ratio is defined as follows. Aperture ratio = effective area contributing to display in one pixel / area of one pixel whole area

That is, the problem is that if the portion of the liquid crystal display element that does not contribute to display is large, the aperture ratio becomes small, and the light use efficiency becomes poor. Examples of the portion that does not contribute to display (light shielding portion) include a metal wiring of each electrode, a nonlinear element or a switching element added as a means for individually controlling each pixel, a gap around a pixel electrode, and the like.

Further, in order to increase the definition with the same liquid crystal display element panel size, it is necessary to reduce the pixel pitch. In this case, if all the constituent elements of the liquid crystal display element can be reduced in a similar manner, the aperture ratio becomes large. Although it does not change, the width of the metal wiring of the electrode and the size of the additional element cannot be reduced to a certain degree or less from the viewpoint of etching accuracy and positioning accuracy.
As a result, there is a problem that the aperture ratio decreases as the definition increases.

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art, and to effectively utilize not only P-polarized light (or S-polarized light) but also S-polarized light (or P-polarized light). Another object of the present invention is to provide a polarization combining element capable of improving light use efficiency and obtaining a bright image, and a liquid crystal display device using the same. Another object of the present invention is to provide a liquid crystal display device that can increase the aperture ratio of a liquid crystal display element, improve light use efficiency, and obtain a bright image.

[0010]

In order to achieve the above object, according to the present invention, an indeterminate polarized light from a light source is converted into a P polarized light and an S polarized light.
A polarizing beam splitter that separates the polarized light into two linearly polarized lights, and a reflecting surface that is arranged so as to be inclined at 45 degrees on optical axes orthogonal to each other, and among the polarized lights separated by the polarizing beam splitter, The s-polarized light (or p-polarized light) is converted to be equal to the polarization direction of the other polarized light (that is, converted to p-polarized light (or s-polarized light)), and is incident on the liquid crystal display device. The polarization combining element is constituted by the right-angle prisms.

[0011] The polarizing beam splitter P obtained by separating by polarized light (or S-polarized light) P-polarized light obtained by converting the polarization direction by the optical axis and the right angle prism (or S-polarized light) Each of the optical axes is eccentric, and in order to prevent a decrease in light use efficiency due to the eccentricity, at least two eccentric optical axes are respectively eccentric.
Configuring a polarization combining element by further adding a heart lens;
did.

[0012] Further, a small number of components constituting the polarization synthesizing element are provided.
Transmits polarized light emitted from at least two eccentric lenses
In the liquid crystal display device for displaying an image , each microlens is arranged so as to be equal to the pixel arrangement in the liquid crystal display device, and the shape of each microlens corresponds to a region corresponding to one pixel. Shape (square,
A flat lens array equal to a rectangle or the like is closely adhered to the transparent substrate on the side where the polarized light is incident, and the focus of each microlens is in or near the liquid crystal layer and substantially in the center of the pixel electrode. To be located at Further, by using a refractive index distribution type microlens array as the flat plate microlens array, it can be used as a transparent substrate of the transmission type liquid crystal display element on the side where the polarized light is incident.

[0013]

The light emitted from the light source is reflected by the concave mirror,
The light enters the focusing lens system. After being converged, the light beam incident on the converging lens system becomes a substantially parallel light beam and impinges on a polarization combining element constituted by a polarizing beam splitter and a right-angle prism.

Here, the light beam emitted from the focusing lens system is indefinitely polarized light, and is incident on a polarizing beam splitter and is separated into P-polarized light and S-polarized light. The path of the S-polarized light (or P-polarized light) separated by the polarizing beam splitter is changed by two right-angle prisms arranged such that the reflecting surfaces are arranged at a 45-degree angle on optical axes orthogonal to each other. Each is bent by 90 degrees and converted into P-polarized light (or S-polarized light). Accordingly, two adjacent light exiting surfaces having different optical axes, namely, the light exiting surface of the polarization beam splitter and the light exiting surface of the right-angle prism, respectively, have the same polarization direction, that is, P-polarized light (or S-polarized light). ) Exit in the same direction and enter the diverging lens system.

The P-polarized light (or S-polarized light)
Is generally diverged by a diverging lens system and enters the liquid crystal display element. Here, since the light beam emitted from the polarization combining element is narrowed down to the liquid crystal display element by the focusing lens system beforehand, the P-polarized light (or S-polarized light) separated and obtained by the polarization beam splitter is obtained. Polarized light)
The use efficiency of light incident on the liquid crystal display element due to the eccentricity of the optical axis of the P-polarized light (or S-polarized light) obtained by changing the polarization direction by the right-angle prism is almost eliminated, and a bright image is obtained. .

In the present invention, instead of the diverging lens system, two eccentric lenses whose optical axes are decentered by a predetermined amount are respectively used for two adjacent exit surfaces having different optical axes (the exit surface of the polarizing beam splitter and the right-angle prism). To correct the deviation of the optical axis of the polarized light emitted from
You . Further, instead of the two right-angle prisms, two reflecting plates such as mirrors may be used.

Further, as in the present invention, by providing a flat microlens in close contact with the transparent substrate on the side where polarized light is incident, incident light is effectively guided to the pixel electrode, and the metal wiring of each electrode is formed. Vignetting of incident light is almost caused by a non-linear element or a switching element added as a means for individually controlling each pixel, or a portion surrounding a pixel electrode, such as a gap, which does not contribute to display (light shielding portion). As a result, a bright image with a large aperture ratio can be displayed.

[0018]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention.
FIG. 2 is a configuration diagram showing a liquid crystal display device which is useful for understanding an example.
However, this will be described.

In FIG. 1, reference numeral 1 denotes a light source, for example, a white light source such as a metal halide lamp and a halogen lamp. 2 is a concave mirror, 3 is a focusing lens system for focusing white light from the light source 1, one lens having a positive power (convex lens) and one lens having a negative power (concave lens) It consists of. Reference numeral 4 denotes a polarization synthesizing element, which is constituted by a polarization beam splitter as polarization means and two right-angle prisms as conversion means.
Reference numeral 5 denotes a diverging lens system for diverging light rays emitted from the polarization combining element 4, and includes a single lens having negative power and a single lens having positive power. Reference numeral 6 denotes a liquid crystal display element, reference numeral 7 denotes a projection lens for enlarging a display image on the liquid crystal display element 6, and reference numeral 8 denotes a screen. Reference numerals 9 to 13 denote drive circuits for the liquid crystal display element 6, of which 9 is a video / chroma processing circuit, 10 is an RGB output circuit, 11 is an X driver, 12 is a synchronization processing circuit, 13 is a controller, and 14 is Y Driver.

Hereinafter, the operation of the present apparatus will be described. In the above configuration, the light source 1 is disposed near the focal position of the concave mirror 2, and the white light from the light source 1 is reflected by the concave mirror 2 to become a substantially parallel light flux, and enters the focusing lens system 3. Light rays incident on the focusing lens system 3 are focused by the lens having positive power of the focusing lens system 3, and become substantially parallel light beams by the lens having negative power.
Is incident on the diverging lens system 5 through. The light beam incident on the diverging lens system 5 is diverged by the lens having a negative power of the diverging lens system 5, becomes a substantially parallel light beam by the lens having a positive power, and enters the liquid crystal display element 6. Then, the image displayed on the liquid crystal display element 6 is enlarged by the projection lens 7, and as a result, an enlarged image is obtained on the screen 8.

A video input from a laser disk, a VTR or the like (not shown) is processed by a video / chroma processing circuit 9 and then input to an RGB output circuit 10. The RGB output circuit 10 inverts the polarity of the video signals corresponding to R, G, and B every vertical period in order to AC drive the liquid crystal display element 6, and inputs the inverted signal to the liquid crystal display element 6 via the X driver 11. The video / chroma processing circuit 9, RGB output circuit 10, X driver 11 and Y driver 14 are synchronized by a synchronization processing circuit 12 and a controller 13.

Next, referring to FIG. 2, the polarization combining element 4 of FIG.
Will be described in detail. FIG. 2 is a perspective view showing the polarization combining element of FIG.

In FIG. 2, reference numeral 15 denotes a polarizing beam splitter as a polarizing means for splitting the indefinitely polarized light into two linearly polarized lights of P-polarized light and S-polarized light, and 16 denotes a polarizing beam splitter. P obtained by
2 as conversion means for converting polarized light into S-polarized light
Right-angle prisms.

The light beam 17 emitted from the focusing lens system 3 and incident on the polarization beam splitter 15 is an irregularly polarized light beam 18, which is
5, the light is separated into two linearly polarized lights, a P-polarized light 19 and an S-polarized light 20. The P-polarized light 19 passes through the polarization beam splitter 15 and directly enters the liquid crystal display element 6 via the diverging lens system 5.

On the other hand, the S-polarized light 20 is reflected by the polarization beam splitter 15 and is incident on two right-angle prisms 16 arranged such that the reflection surfaces are arranged in a state of being inclined at 45 degrees on optical axes orthogonal to each other. Then, while their paths are bent by 90 degrees by the right-angle prisms 16, they are converted into P-polarized light 21 by two reflections while entering the liquid crystal display element 6 via the diverging lens system 5.

As described above, the non-uniform polarized light 18 emitted from the focusing lens system 3 is all
By making the polarized light (P-polarized light 19 and P-polarized light 21) into the liquid crystal display element 6, all of the incident light passes through the polarizing plate of the liquid crystal display element 6. , Among the indeterminate polarized light from the light source, P
Although only one of the linearly polarized light, S-polarized light and S-polarized light, could be used, this apparatus uses almost all of the indefinitely polarized light from the light source, in other words, P-polarized light and S-polarized light.
Both polarized lights of the polarized light can be effectively used, and the light use efficiency can be greatly improved.

As shown in FIG. 2, the polarization combining element 4 in the present apparatus comprises two right-angle prisms 1 as constituent parts.
Although 6 is used, a reflecting plate such as a mirror may be used. However, by using the right-angle prism 16 as in the present apparatus, the components (the polarization beam splitter 15 and the right-angle prism 16) of the polarization combining element 4 can be integrated with each other by optical bonding. Since the light incident on the polarizing beam splitter 15 can be prevented from leaking to the outside until the light is emitted from the right-angle prism 16, the light use efficiency is high and the compact polarization combining element 4 can be realized.

On the other hand, in the diverging lens system 5, as described above, the incident light beam is diverged by the lens having negative power, and is incident on the liquid crystal display element 6 as a substantially parallel light beam by the lens having positive power. However, here, the effective diameter of the lens having negative power of the diverging lens system 5 is larger than the light beam emitted from the polarization combining element 4.
Further, the light beam from the light source 1 is focused by the focusing lens system 3, separated into P-polarized light and S-polarized light in this focused state, and polarization-converted. 6, the light utilization efficiency due to the eccentricity of the optical axes of the P-polarized lights 19 and 21 in the deflecting / combining element 4 hardly decreases, and a bright image can be obtained.

[0029] As described above, conventionally, of indefinite polarized light from a light source, only a one linearly polarized either P-polarized light or S-polarized light which has not been utilized in the apparatus Since almost all of the indefinitely polarized light from the light source, in other words, both the P-polarized light and the S-polarized light can be effectively used, the light use efficiency is greatly improved.

Next, a modification of the apparatus shown in FIG. 1 will be described below. FIG. 3 is a configuration diagram schematically showing a first modification of the apparatus shown in FIG. 1, and particularly shows a configuration of an illumination optical system including a light source 1 to a liquid crystal display element 6. 3, components corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

Hereinafter, specific numerical examples of the present modified example will be described. r ₁ = −d ₁ = −11 (light source surface) r ₂ = −d ₂ = 60 (concave mirror surface) r ₃ = 60 d ₃ = 20 n ₁ = 1.51633 γ ₁ = 64.15 r ₄ = ∞d ₄ = 75 r ₅ = −24 d ₅ = 5 n ₂ = 1.51633 γ ₂ = 64.15 r ₆ = 24 d ₆ = 15 r ₇ = −d ₇ = 10 (incident surface of the polarization combining element) r ₈ = −d ₈ = 15 (polarization combining Element emission surface) r ₉ = −40 d ₉ = 5 n ₃ = 1.51633 γ ₃ = 64.15 r ₁₀ = 40 d ₁₀ = 85 r ₁₁ = ∞d ₁₁ = 18 n ₄ = 1.51633 γ ₄ = 64.15 r ₁₂ = −75 d ₁₂ = 20 r ₁₃ = −d ₁₃ = − (liquid crystal display element surface)

In the above, r _i is the radius of curvature of the i-th lens surface from the light source side, and is positive when the center of curvature is on the liquid crystal display element side and negative when it is on the light source side. d
_i is also the i-th lens surface and adjacent thereto (i + 1)
It represents the distance on the optical axis from the lens surface. n _j , γ _j
Are the refractive index and Abbe number of the j-th lens from the light source side, respectively.

The first surface is a light source surface, and in this modification, a 150 w metal halide lamp was used. The second surface is a concave mirror surface, and has a parabolic shape with a focal length of 11 mm and an effective diameter of 80 mm. The seventh and eighth surfaces are polarization combining element surfaces, and a polarizing beam splitter of 10 mm × 10 mm and 1
It is a right-angle prism of 0 mm × 10 mm. The thirteenth surface is a liquid crystal display element surface, a 3 inch (61 mm × 46 mm) TFT
A liquid crystal display device was used.

Since the light source 1 is disposed at the focal position of the concave mirror 2, the light beam emitted from the light source 1 becomes a parallel light beam,
The light enters the focusing lens system 3 and is focused by the lens having the positive power of the focusing lens system 3, and is converted into a parallel light beam by the lens having the negative power. At this time, the luminous flux emitted from the concave mirror 2 is φ80 mm, and is converged to φ15 mm by the lens having a positive power of the focusing lens system 3.
The light beam is converted into a parallel light beam by a lens having a negative power and is incident on the polarization combining element 4. The luminous flux after exiting the polarization combining element 4 is converted to φ8 by a lens having a negative power of the diverging lens system 5.
The light is diverged to 0 mm, becomes a parallel light beam by a lens having a positive power, and enters the liquid crystal display element 6. At this time,
All the light beams emitted from the polarization combining element 4 are P-polarized light and all pass through the polarizing plate of the liquid crystal display element 6, so that the light use efficiency can be greatly improved.

FIG. 4 is a view schematically showing a second modified example of the apparatus shown in FIG. 1. In particular, FIG. 4 shows the structure of an illumination optical system including the light source 1 to the liquid crystal display element 6. 4, components corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

Hereinafter, specific numerical examples of the present modified example will be described. r ₁ = −d ₁ = −11 (light source surface) r ₂ = −d ₂ = 60 (concave mirror surface) r ₃ = 60 d ₃ = 20 n ₁ = 1.51633 γ ₁ = 64.15 r ₄ = ∞d ₄ = 75 r ₅ = −24 d ₅ = 5 n ₂ = 1.51633 γ ₂ = 64.15 r ₆ = 24 d ₆ = 15 r ₇ = −d ₇ = 10 (incident surface of the polarization combining element) r ₈ = −d ₈ = 15 (polarization combining Element emission surface) r ₉ = 25 d ₉ = 5 n ₃ = 1.51633 γ ₃ = 64.15 r ₁₀ = −25 d ₁₀ = 90 r ₁₁ = ∞d ₁₁ = 20 n ₄ = 1.51633 γ ₄ = 64.15 r ₁₂ = −55 d ₁₂ = 20 r ₁₃ = −d ₁₃ = − (liquid crystal display element surface)

[0037] In the above, r _i is a radius of curvature of the i-th lens surface from the light source side, positive, and negative when there to the light source side when the center of curvature is on the liquid crystal display element side. d
_i is also the i-th lens surface and adjacent thereto (i + 1)
It represents the distance on the optical axis from the lens surface. n _j , γ _j
Are the refractive index and Abbe number of the j-th lens from the light source side, respectively.

The first surface is a light source surface. In this modification, a 150 w metal halide lamp was used. The second surface is a concave mirror surface, and has a parabolic shape with a focal length of 11 mm and an effective diameter of 80 mm. The seventh and eighth surfaces are polarization combining element surfaces, and a polarizing beam splitter of 10 mm × 10 mm and 1
It is a right-angle prism of 0 mm × 10 mm. The thirteenth surface is a liquid crystal display element surface, a 3 inch (61 mm × 46 mm) TFT
A liquid crystal display device was used.

In this modification, the converging lens system 3 is composed of one lens having a positive power and one lens having a negative power, and the diverging lens system 5 has two positive powers. It is constituted by a lens having.

The light source 1 is disposed at the focal position of the concave mirror 2, and the white light from the light source 1 is converted into a parallel light flux and enters the focusing lens system 3. Light rays incident on the focusing lens system 3 are condensed by a lens having a positive power, become substantially parallel light beams by a lens having a negative power, and enter the polarization combining element 4.

This parallel light beam is converted by the polarization
The polarized light is converted into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light enter the diverging lens system 5. Here, the two positive power lenses of the diverging lens system 5 have a focal position on the liquid crystal display element side of the positive power lens on the light source side and a positive power on the liquid crystal display element side. Since the lens is arranged so that the focal position on the light source side coincides with the light source, the light beam incident on the diverging lens system 5 becomes a parallel light beam and enters the liquid crystal display element 6.

FIG. 5 is a schematic diagram showing a third modified example of the apparatus shown in FIG. 1. In particular, FIG. 5 shows the structure of an illumination optical system including the light source 1 to the liquid crystal display element 6. 5, the same reference numerals are given to the components corresponding to those in FIG. 1, and the detailed description thereof will be omitted.

Hereinafter, specific numerical examples in the present modified example will be described. r ₁ = −d ₁ = −11 (light source surface) r ₂ = −d ₂ = 60 (concave mirror surface) r ₃ = 55 d ₃ = 24 n ₁ = 1.51633 γ ₁ = 64.15 r ₄ = ∞d ₄ = 95 r _{5 = 15 d 5 = 5 n} 2 = 1.51633 γ 2 = 64.15 r 6 = -15 d 6 = 15 r 7 = - d 7 = 10 ( polarization combining element incident _{surface) r 8 = - d 8 =} 15 ( polarization combining Element emission surface) r ₉ = −40 d ₉ = 5 n ₃ = 1.51633 γ ₃ = 64.15 r ₁₀ = 40 d ₁₀ = 85 r ₁₁ = ∞d ₁₁ = 20 n ₄ = 1.51633 γ ₄ = 64.15 r ₁₂ = −75 d ₁₂ = 20 r ₁₃ = −d ₁₃ = − (liquid crystal display element surface)

[0044] In the above, r _i is a radius of curvature of the i-th lens surface from the light source side, positive, and negative when there to the light source side when the center of curvature is on the liquid crystal display element side. d
_i is also the i-th lens surface and adjacent thereto (i + 1)
It represents the distance on the optical axis from the lens surface. n _j , γ _j
Are the refractive index and Abbe number of the j-th lens from the light source side, respectively.

The first surface is a light source surface. In this modification, a 150 w metal halide lamp was used. The second surface is a concave mirror surface, and has a parabolic shape with a focal length of 11 mm and an effective diameter of 80 mm. The seventh and eighth surfaces are polarization combining element surfaces, and a polarizing beam splitter of 10 mm × 10 mm and 1
It is a right-angle prism of 0 mm × 10 mm. The thirteenth surface is a liquid crystal display element surface, a 3 inch (61 mm × 46 mm) TFT
A liquid crystal display device was used.

In this modification, the focusing lens system 3 is constituted by two lenses having positive power, and the diverging lens system 5 is constituted by one lens having negative power and one positive power. It is constituted by a lens having.

The light source 1 is disposed at the focal position of the concave mirror 2, and the white light from the light source 1 is converted into a parallel light beam and enters the focusing lens system 3. Here, the two positive power lenses of the focusing lens system 3 are the focal position of the positive power lens on the light source side on the liquid crystal element side and the positive power lens on the liquid crystal display element side. Are arranged so that the focal position on the light source side coincides with the light source side, the light beam incident on the focusing lens system 3 becomes a parallel light beam,
Incident on.

This parallel light beam is converted by the polarization combining element 4 into S
The polarized light is converted into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light enter the diverging lens system 5. The light beam incident on the diverging lens system 5 is diverged by a lens having a negative power in the diverging lens system 5, becomes a parallel light beam by a lens having a positive power, and enters the liquid crystal display element 6.

FIG. 6 is a block diagram schematically showing a fourth modification of the apparatus shown in FIG. 1. In particular, FIG. 6 shows a configuration of an illumination optical system including the light source 1 to the liquid crystal display element 6. 6, components corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

Hereinafter, specific numerical examples of the present modified example will be described. r ₁ = −d ₁ = −11 (light source surface) r ₂ = −d ₂ = 60 (concave mirror surface) r ₃ = 55 d ₃ = 24 n ₁ = 1.51633 γ ₁ = 64.15 r ₄ = ∞d ₄ = 95 r _{5 = 15 d 5 = 5 n} 2 = 1.51633 γ 2 = 64.15 r 6 = -15 d 6 = 15 r 7 = - d 7 = 10 ( polarization combining element incident _{surface) r 8 = - d 8 =} 15 ( polarization combining Element emission surface) r ₉ = 25 d ₉ = 5 n ₃ = 1.51633 γ ₃ = 64.15 r ₁₀ = −25 d ₁₀ = 90 r ₁₁ = ∞d ₁₁ = 20 n ₄ = 1.51633 γ ₄ = 64.15 r ₁₂ = −55 d ₁₂ = 20 r ₁₃ = −d ₁₃ = − (liquid crystal display element surface)

In the above, r _i is the radius of curvature of the i-th lens surface from the light source side, and is positive when the center of curvature is on the liquid crystal display element side and negative when it is on the light source side. d
_i is also the i-th lens surface and adjacent thereto (i + 1)
It represents the distance on the optical axis from the lens surface. n _j , γ _j
Are the refractive index and Abbe number of the j-th lens from the light source side, respectively.

The first surface is a light source surface, and in this modification, a 150 w metal halide lamp was used. The second surface is a concave mirror surface, and has a parabolic shape with a focal length of 11 mm and an effective diameter of 80 mm. The seventh and eighth surfaces are step surfaces of the polarization synthesizing element, and a 10 mm × 10 mm polarization beam splitter and
It is a 10 mm × 10 mm right angle prism. The thirteenth surface is a liquid crystal display element surface, and is a 3 inch (61 mm × 46 mm) TF.
A T liquid crystal display element was used.

In this modification, the focusing lens system 3 is constituted by two lenses having a positive power, and the diverging lens system 5 is constituted by two lenses having a positive power. .

The light source 1 is disposed at the focal position of the concave mirror 2, and the white light from the light source 1 is converted into a parallel light beam and enters the focusing lens system 3. Here, the two positive power lenses of the focusing lens system 3 are the focal position on the liquid crystal element side of the positive power lens on the light source side and the positive power lens on the liquid crystal element side. Since they are arranged so that the focal position on the light source side coincides, the light beam incident on the focusing lens system 3 becomes a parallel light beam and enters the polarization combining element 4.

This parallel light beam is converted by the polarization combining element 4 into S
The polarized light is converted into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light enter the diverging lens system 5. Here, the two positive power lenses of the diverging lens system 5 have a focal position on the liquid crystal display element side of the positive power lens on the light source side and a positive power on the liquid crystal display element side. Since the lens is arranged so that the focal position on the light source side coincides with the light source, the light beam incident on the diverging lens system 5 becomes a parallel light beam and enters the liquid crystal display element 6.

FIG. 7 is a block diagram schematically showing a fifth modification of the apparatus shown in FIG. 1. In particular, FIG. 7 shows a configuration of an illumination optical system including the light source 1 to the liquid crystal display element 6. 7, components corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

Hereinafter, specific numerical examples in this modification will be described. r ₁ = −d ₁ = −11 (light source surface) r ₂ = −d ₂ = 100 (concave mirror surface) r ₃ = 17 d ₃ = 10 n ₁ = 1.51633 γ ₁ = 64.15 r ₄ = −17 d ₄ = 15 r ₅ = −d ₅ = 10 (polarization combining element incident surface) r ₆ = −d ₆ = 15 (polarization combining element incidence surface) r ₇ = −30 d ₇ = 5 n ₂ = 1.51633 γ ₂ = 64.15 r ₈ = _{30 d 8 = 85 r 9 =} ∞ d 9 = 18 n 3 = 1.51633 γ 3 = 64.15 r 10 = -75 d 10 = 20 r 11 = - d 11 = - ( a liquid crystal display device surface)

In the above, r _i is the radius of curvature of the i-th lens surface from the light source side, and is positive when the center of curvature is on the liquid crystal display element side and negative when it is on the light source side. d
_i is also the i-th lens surface and adjacent thereto (i + 1)
It represents the distance on the optical axis from the lens surface. n _j , γ _j
Are the refractive index and Abbe number of the j-th lens from the light source side, respectively.

The first surface is a light source surface, and in this modification, a 150-watt metal halide lamp was used. The second surface is a concave mirror surface and has an oval shape having a focal length of 37 mm, an eccentricity of 0.74, and an effective diameter of 66 mm. The seventh and eighth surfaces are the surfaces of the polarization combining element, which are a polarizing beam splitter of 10 mm × 10 mm and a rectangular prism of 10 mm × 10 mm.
The thirteenth surface is a liquid crystal display element surface, which is 3 inches (61 mm ×
A 46 mm) TFT liquid crystal display element was used.

In this modification, the converging lens system 3 is constituted by one lens having a positive power, and the diverging lens system 5 is constituted by one lens having a negative power and one positive power. It is constituted by a lens having.

The light source 1 is disposed at the first focal position of the concave mirror 2 (the focal position opposite to the liquid crystal display element 6), and white light from the light source 1 is transmitted to the second focal position of the concave mirror 2 (the liquid crystal display element). After focusing once on the focal position on the 6th side), the light enters the focusing lens system 3. Here, for one lens of the focusing lens system 3 having positive power, the second focal position of the concave mirror 2 (the focal position on the liquid crystal display element 6 side) coincides with the focal position of the lens having positive power. Thus, the light beam incident on the focusing lens system 3 becomes a parallel light beam and is incident on the polarization combining element 4.

This parallel light beam is converted by the polarization combining element 4 into S
The polarized light is converted into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light enter the diverging lens system 5. The light beam incident on the diverging lens system 5 is diverged by a lens having a negative power in the diverging lens system 5, becomes a parallel light beam by a lens having a positive power, and enters the liquid crystal display element 6.

FIG. 8 is a configuration diagram schematically showing a sixth modification of the apparatus shown in FIG. 1, and particularly shows the configuration of an illumination optical system including the light source 1 to the liquid crystal display element 6. 8, the same reference numerals are given to the components corresponding to those in FIG. 1, and the detailed description thereof will be omitted.

Hereinafter, specific numerical examples of this modification will be described. r ₁ = −d ₁ = −11 (light source surface) r ₂ = −d ₂ = 100 (concave mirror surface) r ₃ = 17 d ₃ = 10 n ₁ = 1.51633 γ ₁ = 64.15 r ₄ = −17 d ₄ = 15 r ₅ = −d ₅ = 10 (incident surface of the polarization combining element) r ₆ = −d ₆ = 15 (incident surface of the polarization combining element) r ₇ = −30 d ₇ = 5 n ₂ = 1.51633 γ ₂ = 64.15 r ₈ = _{30 d 8 = 85 r 9 =} ∞ d 9 = 18 n 3 = 1.51633 γ 3 = 64.15 r 10 = -75 d 10 = 20 r 11 = - d 11 = - ( a liquid crystal display device surface)

In the above, r _i is the radius of curvature of the i-th lens surface from the light source side, and is positive when the center of curvature is on the liquid crystal display element side and negative when it is on the light source side. d
_i is also the i-th lens surface and adjacent thereto (i + 1)
It represents the distance on the optical axis from the lens surface. n _j , γ _j
Are the refractive index and Abbe number of the j-th lens from the light source side, respectively.

The first surface is a light source surface, and in this modification, a 150 w metal halide lamp was used. The second surface is a concave mirror surface and has an oval shape having a focal length of 37 mm, an eccentricity of 0.74, and an effective diameter of 66 mm. The seventh and eighth surfaces are the surfaces of the polarization combining element, which are a polarizing beam splitter of 10 mm × 10 mm and a rectangular prism of 10 mm × 10 mm.
The thirteenth surface is a liquid crystal display element surface, which is 3 inches (61 mm ×
A 46 mm) TFT liquid crystal display element was used.

In this modification, the focusing lens system 3 is constituted by one lens having a positive power, and the diverging lens system 5 is constituted by two lenses having a positive power.

The light source 1 is disposed at the first focal position of the concave mirror 2 (the focal position opposite to the liquid crystal display element 6), and the white light from the light source 1 is transmitted to the second focal position of the concave mirror 2 (the liquid crystal display element). After focusing once on the focal position on the 6th side), the light enters the focusing lens system 3. Here, for one lens of the focusing lens system 3 having positive power, the second focal position of the concave mirror 2 (the focal position on the liquid crystal display element 6 side) coincides with the focal position of the lens having positive power. Thus, the light beam incident on the focusing lens system 3 becomes a parallel light beam and is incident on the polarization combining element 4.

This parallel light beam is converted by the polarization
The polarized light is converted into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light enter the diverging lens system 5. Here, the two positive power lenses of the diverging lens system 5 have a focal position on the liquid crystal display element side of the positive power lens on the light source side and a positive power on the liquid crystal display element side. Since the lens is arranged so that the focal position on the light source side coincides with the light source, the light beam incident on the diverging lens system 5 becomes a parallel light beam and enters the liquid crystal display element 6.

FIG. 9 is a block diagram schematically showing a seventh modification of the apparatus shown in FIG. 1. In particular, FIG. 9 shows a configuration of an illumination optical system including the light source 1 to the liquid crystal display element 6. 9, the same reference numerals are given to the components corresponding to those in FIG. 1, and the detailed description thereof will be omitted.

Hereinafter, specific numerical examples in this modification will be described. r ₁ = −d ₁ = −11 (light source surface) r ₂ = −d ₂ = 74 (concave mirror surface) r ₃ = −14 d ₃ = 5 n ₁ = 1.51633 γ ₁ = 64.15 r ₄ = 14 d ₄ = 15 r ₅ = −d ₅ = 10 (incident surface of the polarization combining element) r ₆ = −d ₆ = 15 (incident surface of the polarization combining element) r ₇ = −30 d ₇ = 5 n ₂ = 1.51633 γ ₂ = 64.15 r ₈ = _{30 d 8 = 85 r 9 =} ∞ d 9 = 18 n 3 = 1.51633 γ 3 = 64.15 r 10 = -75 d 10 = 20 r 11 = - d 11 = - ( a liquid crystal display device surface)

In the above, r _i is the radius of curvature of the i-th lens surface from the light source side, and is positive when the center of curvature is on the liquid crystal display element side and negative when it is on the light source side. d
_i is also the i-th lens surface and adjacent thereto (i + 1)
It represents the distance on the optical axis from the lens surface. n _j , γ _j
Are the refractive index and Abbe number of the j-th lens from the light source side, respectively.

The first surface is a light source surface, and in this modification, a 150-watt metal halide lamp was used. The second surface is a concave mirror surface and has an oval shape having a focal length of 37 mm, an eccentricity of 0.74, and an effective diameter of 66 mm. The seventh and eighth surfaces are the surfaces of the polarization combining element, which are a polarizing beam splitter of 10 mm × 10 mm and a rectangular prism of 10 mm × 10 mm.
The thirteenth surface is a liquid crystal display element surface, which is 3 inches (61 mm ×
A 46 mm) TFT liquid crystal display element was used.

In this modification, the converging lens system 3 is constituted by one lens having negative power, and the diverging lens system 5 is constituted by one lens having negative power and one positive power. It is constituted by a lens having.

After being reflected by the concave mirror 2, the white light from the light source 1 is incident on the converging lens system 3, is converted into a parallel light beam by the lens having a negative power of the converging lens system 3, and is incident on the polarization combining element 4.

This parallel light beam is converted by the polarization combining element 4 into S
The polarized light is converted into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light enter the diverging lens system 5. The light beam incident on the diverging lens system 5 is diverged by a lens having a negative power in the diverging lens system 5, becomes a parallel light beam by a lens having a positive power, and enters the liquid crystal display element 6.

FIG. 10 is a block diagram schematically showing an eighth modification of the apparatus shown in FIG. 1. In particular, FIG. 10 shows a configuration of an illumination optical system including the light source 1 to the liquid crystal display element 6.
10, the same reference numerals are given to the components corresponding to those in FIG. 1, and the detailed description thereof will be omitted.

Hereinafter, specific numerical examples in this modification will be described. r ₁ = −d ₁ = −11 (light source surface) r ₂ = −d ₂ = 74 (concave mirror surface) r ₃ = −14 d ₃ = 5 n ₁ = 1.51633 γ ₁ = 64.15 r ₄ = 14 d ₄ = 15 r ₅ = −d ₅ = 10 (incident surface of the polarization combining element) r ₆ = −d ₆ = 15 (incident surface of the polarization combining element) r ₇ = 25 d ₇ = 5 n ₂ = 1.51633 γ ₂ = 64.15 r ₈ = − _{25 d 8 = 90 r 9 =} ∞ d 9 = 20 n 3 = 1.51633 γ 3 = 64.15 r 10 = -55 d 10 = 20 r 11 = - d 11 = - ( a liquid crystal display device surface)

In the above, r _i is the radius of curvature of the i-th lens surface from the light source side, and is positive when the center of curvature is on the liquid crystal display element side and negative when on the light source side. d
_i is also the i-th lens surface and adjacent thereto (i + 1)
It represents the distance on the optical axis from the lens surface. n _j , γ _j
Are the refractive index and Abbe number of the j-th lens from the light source side, respectively.

The first surface is a light source surface. In this modification, a 150-watt metal halide lamp was used. The second surface is a concave mirror surface and has an oval shape having a focal length of 37 mm, an eccentricity of 0.74, and an effective diameter of 66 mm. The seventh and eighth surfaces are the surfaces of the polarization combining element, which are a polarizing beam splitter of 10 mm × 10 mm and a rectangular prism of 10 mm × 10 mm.
The thirteenth surface is a liquid crystal display element surface, which is 3 inches (61 mm ×
A 46 mm) TFT liquid crystal element was used.

In the present modification, the converging lens system 3 is constituted by one lens having a negative power, and the diverging lens system 5 is constituted by two lenses having a positive power.

After the white light from the light source 1 is reflected by the concave mirror 2, the light enters the focusing lens system 3, is converted into a parallel light beam by the lens having a negative power of the focusing lens system 3, and is incident on the polarization combining element 4.

This parallel light beam is converted by the polarization combining element 4 into S
The polarized light is converted into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light enter the diverging lens system 5. Here, the two positive power lenses of the diverging lens system 5 have a focal position on the liquid crystal display element side of the positive power lens on the light source side and a positive power on the liquid crystal display element side. Since the lens is arranged so that the focal position on the light source side coincides with the light source, the light beam incident on the diverging lens system 5 becomes a parallel light beam and enters the liquid crystal display element 6.

In each of the modifications described above, the illuminance after passing through the liquid crystal display element was improved from about 1.7 times to about 1.9 times. If an aspherical lens is used as the lens of the focusing lens system 3, the number of lenses can be reduced and the performance such as uneven brightness can be significantly improved.

By the way, in the above-described apparatus of FIG. 1 and each of its modifications, only one liquid crystal display element is used, but the so-called three primary colors (R,
G, B) may be used. Therefore, as an application example for the apparatus of FIG. 1 will be described with reference to FIG. 11 a liquid crystal display device using such a three liquid crystal display devices.

FIG. 11 is a block diagram schematically showing an example of application to the apparatus shown in FIG. 11, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted. In addition, 33 is a total reflection mirror, 34 is a BG reflection dichroic mirror, 35 and 36 are B reflection dichroic mirrors, and 37 is a G reflection dichroic mirror.

The white light emitted from the light source 1 is reflected by the concave mirror 2 and enters the focusing lens system 3. In this application example, the focusing lens system 3 is constituted by one lens having a positive power and one lens having a negative power. The light is converged by a lens having a positive power, and becomes a substantially parallel light beam by a lens having a negative power.

The luminous flux incident on the polarization synthesizing element 4 is converted from S-polarized light into P-polarized light by a polarizing beam splitter and a right-angle prism, and P-polarized light and S-polarized light converted into P-polarized light are transmitted to a diverging lens system 5. Incident. In this application example, the diverging lens system 5 is constituted by one lens having a negative power and one lens having a positive power, and a light beam incident on the diverging lens system 5 is a lens having a negative power. And is emitted as a substantially parallel light beam by a lens having a positive power.

The light beam emitted from the diverging lens system 5 has its path bent by 90 ° by a total reflection mirror 33 arranged at an angle of 45 ° with respect to the optical axis of the light beam. B (blue), G arranged at an angle of 45 °
The light enters the (green) reflecting BG reflecting dichroic mirror 34, B and G are reflected, and R (red) is transmitted.

B and G reflected by the BG reflection dichroic mirror 34 are incident on a B reflection B reflection dichroic mirror 35 of B reflection arranged at an angle of 45 ° with respect to the optical axis of the light beam, and B is a B reflection dichroic mirror. Reflects 35,
G is incident on the liquid crystal display element 6 for B, and G passes through the B reflection dichroic mirror 35 and is incident on the liquid crystal display element 6 for G. On the other hand, R transmitted through the BG reflection dichroic mirror 34 has its path bent by 90 ° by the total reflection mirror 33 arranged at an angle of 45 ° with respect to the optical axis of the light beam, and the liquid crystal display element 6 for R Incident on.

Further, B emitted from the liquid crystal display element 6 for B is reflected by a B reflection dichroic mirror 36 of B reflection arranged at an angle of 45 ° with respect to the optical axis of the light beam, and the light of the light beam is reflected. The light passes through a G reflection dichroic mirror 37 of G reflection arranged at an angle of 45 ° with respect to the axis, and enters the projection lens 7.

G emitted from the liquid crystal display element 6 for G is reflected by the total reflection mirror 33 disposed at an angle of 45 ° with respect to the optical axis of the light beam, and is reflected by 45 ° with respect to the optical axis of the light beam. G reflection dichroic mirror 37 of G reflection arranged at an angle of
And is incident on the projection lens 7. R emitted from the R liquid crystal display element 6 is reflected by the B reflection dichroic mirror 36.
Through the G reflection dichroic mirror 37,
The light enters the projection lens 7.

The image displayed on the R, G, and B liquid crystal display elements 6 is enlarged by the projection lens 7, and as a result, an enlarged image is obtained on the screen 8.
Here, the optical axes of R, G, and B emitted from each liquid crystal display element 6 and incident on the projection lens 7 coincide with each other.
Further, since the distance from each liquid crystal display element 6 to the projection lens 7 is the same, an enlarged color image in which R, G, and B are combined is obtained on the screen 8.

Next, based on the above, one embodiment of the present invention will be described.
A liquid crystal display device using a polarization combining element different from that of the device of FIG. 1 will be described. FIG.
1 is a configuration diagram illustrating a liquid crystal display device as one embodiment . 12, the components corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted. In addition, 4 'is a polarization combining element.

Hereinafter, the operation of this embodiment will be described.
In the above configuration, the light source 1 is disposed near the focal position of the concave mirror 2 (here, a parabolic shape), and the white light from the light source 1 is reflected by the concave mirror 2 to become a substantially parallel light flux, and enters the focusing lens system 3. I do. Light rays incident on the focusing lens system 3 are focused by the lens having a positive power of the focusing lens system 3, and the area of the cross section thereof is about １ ／ of the area of the display surface of the liquid crystal display element 6. Then, the light is converted into a substantially parallel light beam by a lens having a negative power and is incident on the polarization combining element 4 '. Therefore, by passing through the converging lens system 3, the light beam has a cross-sectional area of about １ ／ of the display surface area of the liquid crystal display element 6 while maintaining a parallel light beam state.
And enters the polarization combining element 4 ′. Specifically, in this embodiment, a panel equivalent to 1.7 inches is used as the liquid crystal display element 6, and the light beam is narrowed down to φ15 mm through the focusing lens system 3.

The light beam emitted from the polarization combining element 4 ′ enters the liquid crystal display element 6. Then, the image displayed on the liquid crystal display element 6 is enlarged by the projection lens 7, and as a result, an enlarged image is obtained on the screen 8.

A video input from a laser disk, VTR or the like (not shown) is processed by a video / chroma processing circuit 9 and then input to an RGB output circuit 10. The RGB output circuit 10 inverts the polarity of the video signals corresponding to R, G, and B every vertical period in order to AC drive the liquid crystal display element 6, and inputs the inverted signal to the liquid crystal display element 6 via the X driver 11. The video / chroma processing circuit 9, RGB output circuit 10, X driver 11 and Y driver 14 are synchronized by a synchronization processing circuit 12 and a controller 13.

Next, the configuration and operation of the polarization combining element 4 'in FIG. 12 will be described in detail with reference to FIG. FIG.
FIG. 13 is a perspective view showing the polarization combining element of FIG. In FIG. 13, components corresponding to those in FIG.
The detailed description is omitted. In addition, 40 is an eccentric lens whose lens optical axis is decentered by a predetermined amount, 41 is an exit surface of the polarizing beam splitter 15, and 42 is an exit surface of the right-angle prism 16.

The light beam 17 emitted from the converging lens system 3 and incident on the polarizing beam splitter 15 (15 mm × 15 mm in this embodiment) is an irregularly polarized light 18.
Reference numeral 8 denotes P-polarized light by the polarization beam splitter 15.
9 and S-polarized light 20 are separated into two linearly-polarized lights.

The P-polarized light 19 passes through the polarization beam splitter 15 and directly enters the eccentric lens 40 via the exit surface 41. The eccentric lens 40 enlarges the P-polarized light 19 by about 2 times. 6 is incident.

On the other hand, the S-polarized light 20 is reflected by the polarization beam splitter 15 and is incident on two right-angle prisms 16 arranged such that the reflection surfaces are arranged in a state of being inclined at 45 degrees on optical axes orthogonal to each other. The path is bent by 90 degrees by the right-angle prisms 16 and converted into P-polarized light 21 by two reflections while being bent by 90 degrees.
2, the light enters the eccentric lens 40, and the eccentric lens 4
The light is magnified about twice by 0 and enters the liquid crystal display element 6.

Next, the configuration and operation of the eccentric lens 40 of FIG. 13 will be described with reference to FIG. FIG. 14 shows FIG.
FIG. 2 is a front view showing the polarization combining element viewed from the liquid crystal display element side. In FIG. 14, reference numeral 43 denotes a display surface of the liquid crystal display element 6 (an area indicated by a chain line).

As shown in FIG. 13, the eccentric lens 40 is attached to the exit surface 41 of the polarizing beam splitter 15 and the exit surface 42 of the right angle prism 16, respectively. Here, the exit surface 41 of the polarizing beam splitter 15
The area of each of the exit surfaces 42 of the right-angle prism 16 and FIG.
As shown in FIG. 4, the area is set to about １ ／ of the area of the display surface 43 of the liquid crystal display element 6, and the output surface 41 of the polarizing beam splitter 15 and the output surface 4
Position 2 (position in the direction perpendicular to the optical axis) is arranged so as to have a positional relationship as shown in FIG. 14 with respect to the position of the display surface 43 of the liquid crystal display element (position in the direction perpendicular to the optical axis). Have been.

As shown in FIG. 14, each eccentric lens 40 cuts a part of the plano-concave lens 44 shown by a dotted line in accordance with the eccentric amount of each of the exit surfaces 41 and 42. It is obtained.

Here, the diameter of the plano-concave lens 44 is D (21.2 mm in this embodiment) with the diagonal of the exit surfaces 41 and 42 being the same.
In this case, the focal length is set to 2D, and the focal length is set such that the magnification is about twice as large as the distance between the polarization combining element 4 ′ and the liquid crystal display element 6. I have.

Accordingly, as shown in FIG. 14, the exit surface 4 of the polarizing beam splitter 15 is
When the portion 1 and the portion of the exit surface 42 of the right-angle prism 16 are respectively enlarged about twice, the enlarged images coincide with each other at the position of the liquid crystal display element 6 (position in the optical axis direction). At the same time, it coincides with the display surface 43 of the liquid crystal display element 6. Supplement explanation here
And the diverging lens system, the optical axis
When the concave lens (44) is arranged according to the position,
Light emitted from the outer edge of the element passes through the optical axis position of the lens.
The angle of the light beam does not change due to
And then reaches the diagonal position of the liquid crystal display element. one
On the other hand, the light rays coming out of the center of the polarization
The angle of the light beam changes because it passes through a place away from the optical axis position.
And passes at an angle to the optical axis. Ray angle
Is positioned so that it reaches the opposite diagonal position of the liquid crystal display.
Lens focal length. (2x magnification)
Therefore, the area of the light beam emitted from the polarization combining element is quadrupled.
Spreads and reaches the entire area of the liquid crystal display element evenly
It becomes possible.

Therefore, the P-polarized light 19 emitted from the exit surface 41 of the polarizing beam splitter 15 via the eccentric lens 40 and the P-polarized light emitted from the exit surface 42 of the right-angle prism 16 via the eccentric lens 40 21 means
At the position of the liquid crystal display element 6 (position in the optical axis direction), they are synthesized so as to coincide with each other, and are incident on the display surface 43 of the liquid crystal display element 6 without excess or shortage.

As described above, the P-polarized lights 19 and 21 respectively emitted from the exit surface 41 of the polarization beam splitter 15 and the exit surface 42 of the right-angle prism 16 are enlarged about twice by the eccentric lens 40, and Display surface 4 of display element 6
3, the diverging lens system 5 used in the apparatus of FIG. 1 can be omitted, and a more compact liquid crystal display device can be obtained.

It is assumed that the magnification of the eccentric lens 40 (that is, the magnification of the plano-concave lens 44) is larger than the above-mentioned twice with respect to the distance between the polarization combining element 4 'and the liquid crystal display element 6. Then, an enlarged image of the portion of the exit surface 41 of the polarization beam splitter 15 and the portion of the exit surface 42 of the right-angle prism 16 becomes larger than the display surface 43 of the liquid crystal display element 6, and the light utilization rate is greatly reduced. . Conversely, if the magnification is smaller than twice, the magnified image will be smaller than the display surface 43 of the liquid crystal display element 6, resulting in uneven brightness. Therefore, as described above, it is very important in this embodiment to set the magnification of the eccentric lens 40 to about twice the distance between the polarization combining element 4 'and the liquid crystal display element 6. .

As described above, in the present embodiment, among the indefinitely polarized lights from the light source, only one of the P-polarized light and the S-polarized light was used. Can effectively use almost all of the indefinitely polarized light from the light source, in other words, both the P-polarized light and the S-polarized light, so that the light use efficiency is greatly improved. In this example, the illuminance after passing through the liquid crystal display element was improved by about 1.9 times.

Further, according to this embodiment, the P-polarized light emitted from the exit surface of the polarizing beam splitter and the exit surface of the right-angle prism are magnified about twice by the eccentric lens, and the Since the images can be synthesized on the display surface, the diverging lens system can be omitted, and a more compact liquid crystal display device can be obtained.

Further, since the light from the light source is focused to about ４ of the area of the display surface of the liquid crystal display element by the focusing lens system, each component of the polarization synthesizing element can be downsized, which is advantageous in cost. Becomes

Further, as shown in FIG. 13, the polarization combining element 4 'in this embodiment has its components (polarizing beam splitter 15, right angle prism 16, and eccentric lens 40) mutually optically. The light beam incident on the polarizing beam splitter 15 can be prevented from leaking to the outside until the light beam enters the polarizing beam splitter 15 from the eccentric lens 40. Can be realized. Also, the eccentric lens 40
As shown in FIG. 15, one plano-concave lens 4
It is also advantageous that four to four eccentric lenses 40 can be created.

In this embodiment, further effects can be expected by further providing a correction lens as described below between the polarization combining element 4 'and the liquid crystal display element 6.

FIG. 16 is a structural view showing a correction lens provided between the polarization combining element and the liquid crystal display element of FIG. 16, the same reference numerals are given to the components corresponding to those in FIG. 12, and the detailed description thereof will be omitted. Other, 45
Is a correction lens. As shown in FIG. 16, the correction lens 45 is composed of a lens having a positive power, and is provided between the polarization combining element 4 ′ and the liquid crystal display element 6 and between the polarization combining element 4 ′ and the liquid crystal display element 6.
Is provided in the vicinity of.

Therefore, the eccentric lens 40 of the polarization combining element 4
The divergent light beam emitted from the device is converted into a parallel light beam by the correction lens 45 having a positive power just before the liquid crystal display element 6, and enters the liquid crystal display element 6. Thereby, the influence on the contrast performance due to the angle dependence of the incident light beam peculiar to the liquid crystal display element can be improved.

Next, a modification of the embodiment of FIG. 12 described above will be described below. FIG. 17 is a configuration diagram schematically showing a first modification of the embodiment of FIG. 12, and particularly shows the configuration of an illumination optical system including the light source 1 to the liquid crystal display element 6. 17, components corresponding to those in FIG. 12 are denoted by the same reference numerals, and detailed description thereof will be omitted. In this modification, the focusing lens system 3 is constituted by two lenses having positive power.

The light source 1 is arranged in the vicinity of the focal point of the concave mirror 2. White light from the light source 1 is reflected by the concave mirror 2 to become a substantially parallel light beam, and enters the focusing lens system 3. The light beam incident on the focusing lens system 3 is focused by the lens having a positive power on the light source side near the focal point of the lens, and the area of the cross section thereof is about 1 area of the display surface of the liquid crystal display element 6. When the size becomes / 4, the lens having a positive power on the side of the polarization combining element becomes almost parallel light flux,
The light enters the polarization combining element 4 '. Then, this parallel light beam is converted by the polarization combining element 4 ′ into S-polarized light into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light are combined and incident on the liquid crystal display element 6. . Thus, even if the focusing lens system 3 is configured by two lenses having positive power, the same operation as the focusing lens system 3 in FIG. 12 can be obtained.

FIG. 18 is a block diagram schematically showing a second modification of the embodiment shown in FIG. 12, and particularly shows a configuration of an illumination optical system including the light source 1 to the liquid crystal display element 6. 18, the same reference numerals are given to components corresponding to those in FIG. 12, and detailed description thereof will be omitted. In this modification, the concave mirror 2 is formed into an elliptical shape (or a so-called multi-mirror).
And the converging lens system 3 is constituted by one lens having a positive power.

The light source 1 is disposed near a focal position (hereinafter, referred to as a front elliptical focal point) near the center of the concave mirror 2, and white light from the light source 1 is reflected by the concave mirror 2 and reflected by the concave mirror 2.
Focusing on a focal point near the focusing lens system 3 (hereinafter referred to as a rear elliptical focal point), and the cross-sectional area thereof is about 1/4 of the area of the display surface of the liquid crystal display element 6. When the size becomes large, the light enters the focusing lens system 3. The light beam incident on the focusing lens system 3 is converted into a substantially parallel light beam by a lens having a positive power, and is incident on the polarization combining element 4 '.
Then, this parallel light beam is converted by the polarization combining element 4 ′ into S-polarized light into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light are combined and incident on the liquid crystal display element 6. .

As described above, even when the concave mirror 2 is constituted by an elliptical concave mirror and the focusing lens system 3 is constituted by one lens having a positive power, the same operation as the focusing lens system 3 in FIG. Obtainable.

FIG. 19 is a schematic diagram showing a third modification of the embodiment shown in FIG. 12, and particularly shows the structure of an illumination optical system including the light source 1 to the liquid crystal display element 6. In FIG. 19, components corresponding to those in FIG. 12 are denoted by the same reference numerals, and detailed description thereof will be omitted. In this modification, the concave mirror 2 is formed into an elliptical shape (or a so-called multi-mirror).
And the converging lens system 3 is constituted by one lens having a negative power.

The light source 1 is disposed in the vicinity of the front elliptical focal point of the concave mirror 2, and the white light from the light source 1 reflects off the concave mirror 2 and converges in the vicinity of the rear elliptical focal point of the concave mirror 2. When the area of the cross section becomes about １ ／ of the area of the display surface of the liquid crystal display element 6, the light enters the focusing lens system 3. The light beam incident on the focusing lens system 3 is converted into a substantially parallel light beam by a lens having a negative power, and is incident on the polarization combining element 4 '. Then, this parallel light beam is converted by the polarization combining element 4 ′ into S-polarized light into P-polarized light, and the P-polarized light and the S-polarized light converted into P-polarized light are combined and incident on the liquid crystal display element 6. .

As described above, even when the concave mirror 2 is constituted by an elliptical concave mirror and the focusing lens system 3 is constituted by one lens having a negative power, the same operation as the focusing lens system 3 in FIG. Obtainable.

It is needless to say that the same function as the converging lens system 3 in FIG. 12 can be obtained even if the converging lens system 3 is configured to have a number (two or more) of lenses other than those described above. Further, if an aspherical lens is used as the lens of the focusing lens system 3, the number of lenses and the performance such as uneven brightness can be remarkably improved.

In the above-described embodiment of FIG. 12 and each of its modifications, only one liquid crystal display element is used. However, the embodiment corresponds to so-called three primary colors (R, G, B). It is also possible to use three liquid crystal display elements. Therefore, as an application example to the embodiment of FIG. 12, a liquid crystal display device using such three liquid crystal display elements will be described with reference to FIG.

FIG. 20 is a block diagram schematically showing an example of an application to the embodiment of FIG. In FIG. 20, FIG.
Components corresponding to those in FIG. 16 are denoted by the same reference numerals, and detailed description thereof will be omitted. In addition, 33 is a total reflection mirror, 46
Is a BR reflection dichroic mirror, 47 and 48 are R reflection dichroic mirrors, and 49 is an RG reflection dichroic mirror.

The light source 1 is disposed near the focal point of the concave mirror 2 (here, a parabolic shape). The white light from the light source 1 is reflected by the concave mirror 2 to become a substantially parallel light flux, and enters the focusing lens system 3. . Light rays incident on the focusing lens system 3 are focused by the lens having a positive power of the focusing lens system 3, and the area of the cross section thereof is about １ ／ of the area of the display surface of the liquid crystal display element 6. Then, the light is converted into a substantially parallel light beam by a lens having a negative power and is incident on the polarization combining element 4 '.

The light beam incident on the polarization synthesizing element 4 'is separated into two-way linearly polarized light of S-polarized light and P-polarized light by a polarizing beam splitter, and the S-polarized light is converted to P-polarized light by two right-angle prisms. The P-polarized light and the S-polarized light converted to P-polarized light are incident on the eccentric lens via the polarizing beam splitter and the exit surface of the right-angle prism, and are expanded about twice by the eccentric lens. Out of the polarization combining element 4 ′ so that the light is combined on the surface of each liquid crystal display element 6.

The light beam emitted from the polarization synthesizing element 4 ′ is bent at 90 ° by the total reflection mirror 33 disposed at an angle of 45 ° with respect to the optical axis of the light beam, and the optical axis of the light beam is B (blue) arranged at an angle of 45 ° to
BR reflection dichroic mirror 46 that reflects R (red)
, B and R are reflected, and G (green) is transmitted.

The B and R reflected by the BR reflection dichroic mirror 46 are incident on an R reflection dichroic mirror 47 which reflects only R arranged at an angle of 45 ° with respect to the optical axis of the light beam, and R is R reflection. The liquid crystal display element 6 for R reflects off the dichroic mirror 47 and passes through the correction lens 45.
Incident on. B is an R reflection dichroic mirror 4
7 and enter the liquid crystal display element 6 for B via the correction lens 45.

On the other hand, the G transmitted through the BR reflecting dichroic mirror 46 has its path of nine rays by a total reflection mirror 33 arranged at an angle of 45 ° with respect to the optical axis of the light beam.
After being bent by 0 °, the light enters the liquid crystal display element 6 for G via the correction lens 45. Thus, images corresponding to R, G, and B are separately obtained.

Further, the R emitted from the R liquid crystal display element 6 reflects an R reflecting dichroic mirror 48 which reflects the R arranged at an angle of 45 ° with respect to the optical axis of the light beam, R arranged at an angle of 45 ° to the optical axis
Then, the light is reflected by an RG reflection dichroic mirror 49 which reflects G and G, and enters the projection lens 7.

G emitted from the liquid crystal display element 6 for G passes through the R reflection mirror 48 arranged at an angle of 45 ° with respect to the optical axis of the light beam, and 45 G with respect to the optical axis of the light beam. The RG reflection dichroic mirror 4 arranged at an angle of
9 and is incident on the projection lens 7 in the same manner as R.

The path of B emitted from the liquid crystal display element 6 for B is bent by 90 ° by the total reflection mirror 33 arranged at an angle of 45 ° with respect to the optical axis of the light beam, and further the RG Transmits through the reflecting dichroic mirror 49,
The light enters the projection lens 7 in the same manner as R and G.

The image displayed on the R, G, and B liquid crystal display elements 6 is enlarged by the projection lens 7 to obtain an enlarged image on the screen 8. Here, R, which emits each liquid crystal display element 6 and irradiates the projection lens 7,
G and B have the same optical axis, and furthermore, the distance from each liquid crystal display element to the projection lens 7 is the same, so that the color in which R, G and B are combined on the screen 8 is enlarged. An image is obtained.

Further, in this application example, similarly to the embodiment of FIG. 12, the light beam from the light source 1 is condensed by the focusing lens system 3 so that the area of the cross section thereof is about 1 area of the display area of the liquid crystal display element 6. / 4, so that each component part of the polarization combining element 4 'can be miniaturized, and in addition to the polarizing lens of the polarization combining element 4', the polarizing lens of the polarizing beam splitter and the exit surface of the right-angle prism can be used. Even if each portion is enlarged, the enlarged image coincides with the display surface of the liquid crystal display element 6 and does not become larger. Therefore, the total reflection mirror 33 provided between the polarization combining element 4 'and the liquid crystal display element 6 is used.
This is advantageous in that the size of the dichroic mirrors 46, 47, and 48 (so-called color separation optical system) does not need to be larger than before.

In each of the embodiments described above, the polarizing plate of the liquid crystal display element 6 allows the P-polarized light to pass therethrough. After the light is separated into P-polarized light and S-polarized light by a polarizing beam splitter, the S-polarized light is converted into P-polarized light by two right-angle prisms, all of which are converted into P-polarized light and incident on the liquid crystal display element 6. However, when the polarizing plate of the liquid crystal display element 6 allows S-polarized light to pass through, the P-polarized light is converted into S-polarized light by two right-angle prisms in the polarization combining element 4 or 4 '. hand,
It goes without saying that it is only necessary to make all S-polarized light and enter the liquid crystal display element 6.

In each of the embodiments described above, a general liquid crystal display element as shown in FIG. 21 is used as the liquid crystal display element 6. FIG. 21 is a perspective view showing a general liquid crystal display element.

In FIG. 21, reference numeral 22 denotes a pair of transparent substrates, and a transparent counter electrode 23 is provided on a surface facing one transparent substrate 22, and a transparent pixel electrode 23 is provided on a surface facing the other transparent substrate 22. The liquid crystal 24 is sealed between the pair of transparent substrates 22.
Reference numeral 26 denotes a metal wiring of each electrode provided on the other transparent substrate 22, a non-linear element and a switching element added as means for individually controlling each pixel, and a display formed by a gap around the pixel electrode. This is a portion that does not contribute (light shielding portion). Numeral 27 is a polarizing plate provided outside each of the transparent substrates 22 and 22. In the figure, the polarizing plate 27 and the transparent substrate 22 are drawn apart from each other, but they may be in close contact with each other.

As described above, since the liquid crystal display element 6 shown in FIG. 21 has a portion (light-shielding portion) 26 that does not contribute to display, the portion (light-shielding portion) 26 that does not contribute to display is provided as described above. If it is large, the aperture ratio becomes small, and there is a problem that the light use efficiency is deteriorated.

Therefore, as another embodiment of the present invention, an embodiment which solves the above problem will be described below. FIG. 22 is a perspective view showing a liquid crystal display element used in a liquid crystal display device as another embodiment of the present invention.

In FIG. 22, components corresponding to those in FIG. 21 are denoted by the same reference numerals, and detailed description thereof will be omitted. In addition, reference numeral 6 'denotes a liquid crystal display element, and reference numeral 28 denotes a flat plate microlens array, which is a refractive index distribution type which is a feature of the present embodiment, and which is substantially a two-dimensional array as shown by a broken line in the figure. is there. 29 is an incident light beam and 30 is an outgoing light beam.

The flat microlens array 28 includes the liquid crystal 24
Is always provided on the incident light beam 29 side. That is, when the outgoing light beam 30 in the figure becomes an incident light beam, the flat microlens array 28 is provided on the other transparent substrate 22 side in the figure.

Next, the positional relationship and the shape of the constituent elements, which are features of this embodiment, will be described with reference to FIG. FIG.
FIG. 3 is a plan view schematically illustrating the positional relationship between the components in the liquid crystal display element of FIG.

In FIG. 23, components corresponding to those in FIG. 22 are denoted by the same reference numerals, and detailed description thereof will be omitted. In addition, 31 (shaded area) is an area corresponding to one pixel in the liquid crystal 24 in FIG.

In a region 31 (hatched region) corresponding to one pixel, a solid line frame is a pixel electrode 25 effective for display (that is, light is transmitted), and the other is a display of a metal wiring, a switching element, or the like. (Light shielding portion) 26 which does not contribute to the above. The dotted frame in the figure indicates the individual lens shape of the microlens array 28.

The feature of this embodiment is that, as shown in the figure, the individual lens shapes of the flat microlens array 28 have the same shape and the same arrangement as the shape of the region 31 corresponding to one pixel in the liquid crystal 24. It is a point that was made.

The inventors of the present invention have adopted a flat microlens array 28 corresponding to one pixel of liquid crystal, that is, an embedded three-dimensional refractive index distribution type having a square shape such as a square or a rectangle and a binary matrix. It has been found that a lens can be manufactured by developing a conventional ion exchange technique and performing selective ion exchange on a flat substrate glass.

Next, the operation of the flat microlens array 28 will be described with reference to FIG. FIG. 24 shows FIG.
It is sectional drawing which shows the principal cross sections in the liquid crystal display element of No. 2. In FIG. 24, reference numeral 32 denotes an individual refractive index distribution region (lens portion) of the flat microlens array 28.

The refraction distribution region 32 may be provided on either side of the flat microlens array 28 as shown in the figure. However, providing on the transparent substrate 22 side is advantageous in terms of manufacturing technology because the focal length of the lens can be shortened.

Further, by adjusting the refractive index distribution region 32, the focal point is set in or near the layer of the liquid crystal 24 and at the center of the pixel electrode 25. As a result, the incident light beam 29 parallel to the optical axis passing through the polarizing plate (not shown) is
8, the light does not pass through a portion (light-shielding portion) 26 that does not contribute to display, such as a metal wiring and a switching element, so that the deterioration of the light utilization rate depending on the conventional aperture ratio is greatly improved.

Next, a modification of the embodiment of FIG. 22 described above will be described below. FIG. 25 is a perspective view showing a modification of the embodiment shown in FIG. 25, components corresponding to those in FIG. 22 are denoted by the same reference numerals, and detailed description thereof will be omitted. In this modification, the flat microlens array 28 is used as a substrate on one side of the liquid crystal 24.

As described above, by using the refractive index distribution type as the flat microlens array 28, the appearance of the flat microlens array 28 becomes a flat plate with high accuracy, so that it can be sufficiently used as a substrate. Also, as shown in FIG. 23, each lens shape of the flat plate micro lens array 28 has the same shape and the same arrangement as the shape of the region corresponding to one pixel in the liquid crystal 24, and As shown in FIG. 24, the refractive index distribution region of the array may be provided on either side, as in the embodiment of FIG.

Although not shown, it is necessary to undercoat a protective film between the flat microlens array 28 and the liquid crystal 24 in order to prevent liquid crystal deterioration due to elution of alkali ions from the flat microlens array 28.

According to this modification, the distance from the rear principal point of the lens in the flat microlens array 28 to the liquid crystal 24 can be greatly shortened, so that the aperture ratio depends on the angle of the incident light. There is an advantage that the influence of is almost eliminated.

[0157]

Conventionally, more than half of the light from the light source is absorbed by the polarizing plate of the liquid crystal display element, and only one of the P-polarized light and the S-polarized light can be used. However, according to the present invention, since the light from the light source is polarization-converted, almost all of the light can be converted into either one of the P-polarized light and the S-polarized light to be incident on the liquid crystal display element. Almost all of the light from the light source, in other words, both P-polarized light and S-polarized light can be effectively used, and the light use efficiency can be greatly improved.

Further, according to the present invention, since the aperture ratio of the liquid crystal display element can be increased, the effective utilization of light can be greatly improved. Accordingly, a liquid crystal display device with a bright screen can be realized as described above. Further, according to the present invention, since the light from the light source is once condensed by the focusing lens system, each component of the polarization combining element can be realized in a small size.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a liquid crystal display device which is useful for understanding an embodiment of the present invention.

FIG. 2 is a perspective view showing the polarization combining element of FIG.

FIG. 3 is a configuration diagram schematically showing a first modification of the apparatus of FIG. 1;

FIG. 4 is a configuration diagram schematically showing a second modification of the apparatus shown in FIG. 1;

FIG. 5 is a configuration diagram schematically showing a third modification of the apparatus of FIG. 1;

FIG. 6 is a configuration diagram schematically showing a fourth modification of the apparatus of FIG. 1;

FIG. 7 is a configuration diagram schematically showing a fifth modification of the apparatus of FIG. 1;

FIG. 8 is a configuration diagram schematically showing a sixth modification of the apparatus of FIG. 1;

FIG. 9 is a configuration diagram schematically showing a seventh modification of the apparatus of FIG. 1;

FIG. 10 is a block diagram schematically showing an eighth modification of the apparatus shown in FIG.

FIG. 11 is a configuration diagram schematically showing an example of application to the device of FIG. 1;

FIG. 12 is a configuration diagram showing a liquid crystal display device as one embodiment of the present invention.

FIG. 13 is a perspective view showing the polarization combining element of FIG.

FIG. 14 is a front view showing the polarization combining element of FIG. 13 as viewed from the liquid crystal display element side.

FIG. 15 is an explanatory diagram for describing a method of producing the eccentric lens of FIG.

FIG. 16 is a configuration diagram illustrating a correction lens provided between the polarization combining element and the liquid crystal display element of FIG.

FIG. 17 is a configuration diagram schematically showing a first modification of the embodiment shown in FIG. 12;

FIG. 18 is a configuration diagram schematically showing a second modification of the embodiment shown in FIG.

FIG. 19 is a configuration diagram schematically showing a third modification of the embodiment shown in FIG. 12;

FIG. 20 is a configuration diagram schematically showing an application example to the embodiment of FIG. 12;

FIG. 21 is a perspective view showing a general liquid crystal display element.

FIG. 22 is a perspective view showing a liquid crystal display element used in a liquid crystal display device as another embodiment of the present invention.

FIG. 23 is a plan view schematically drawn to explain the positional relationship between components in the liquid crystal display element of FIG. 22.

24 is a cross-sectional view showing a main cross section of the liquid crystal display device of FIG.

FIG. 25 is a perspective view showing a modification of the embodiment shown in FIG. 22;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Light source, 2 ... Concave mirror, 3 ... Converging lens system, 4,4 '...
Polarization combining element, 5 divergent lens system, 6, 6 'liquid crystal display element, 7 projection lens, 8 screen, 9 video chroma processing circuit, 10 RGB output circuit, 11 X driver, 12 synchronization processing Circuit, 13 ... Controller, 14 ...
Y driver, 15: polarizing beam splitter, 16: right angle prism, 17: light beam, 18: non-uniform polarized light, 19, 2
1: P-polarized wave, 20: S-polarized wave, 22: Transparent substrate, 23
... counter electrode, 24 ... liquid crystal, 25 ... pixel electrode, 26 ... light shielding part, 27 ... polarizing plate, 28 ... flat plate micro lens array,
29: incident light beam, 30: outgoing light beam, 31: area corresponding to one pixel, 32: refractive index distribution area, 33: total reflection mirror, 34: BG reflection dichroic mirror, 35, 36
... B reflection dichroic mirror, 37 ... G reflection dichroic mirror, 40 ... eccentric lens, 41 ... polarizing beam splitter exit surface, 42 ... right angle prism exit surface, 43 ...
Magnified image, 44: plano-concave lens, 45: correction lens, 46:
BR reflection dichroic mirror, 47, 48 ... R reflection dichroic mirror, 49 ... RG reflection dichroic mirror.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaharu Exit 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside Hitachi, Ltd.Video Media Research Laboratories (72) Inventor Maruyama Takesuke 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Address: Hitachi, Ltd. Visual Media Research Laboratories (56) References JP-A-1-187502 (JP, A) JP-A-61-122626 (JP, A) JP-A-1-88902 (JP, U) Hei 2-128103 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G02B 27/28 G02F 1/13 G02F 1/1335

Claims (7)

(57) [Claims] An indeterminately polarized light is incident, and a P-polarized light and an S-polarized light are incident.
Light, and one of the polarized light is emitted to the first
Surface, and the other polarized light is emitted from the second emission surface.
And at the first exit surface, the first exit surface
The cross-sectional area of the polarized light emitted from the
A liquid crystal display element arranged behind the light emitting side of the combining element
Polarizing beam splitter that is approximately 1/4 of the area of the display surface of the element
And at least a first and a second reflecting surface,
The optical axis of the incident light with respect to the first reflecting surface and the optical axis of the reflected light
Optical axis and reflection of incident light on the surface including and the second reflection surface
The plane including the optical axis of the light is orthogonal to each other, and the first
Angle of incidence of incident light on the reflecting surface of the
So that the reflection angle of the reflected light with respect to each becomes 45 degrees.
Disposing the first and second reflecting surfaces, and
The polarized light emitted from the second emission surface of the splitter is
The light is incident on the first reflection surface and its polarization direction is
The polarization emitted from the first emission surface of the beam splitter.
The light is converted to be equal to the polarization direction of the light, and the second
The light exits from the reflection surface through the emission surface, and the emission surface
At the side of the polarized light emitted through the emission surface
The area of the cross section is approximately one area of the display surface of the liquid crystal display element.
/ 4 reflecting means and the polarizing beam splitter.
The polarized light emitted from the first emission surface and the reflecting means
And the polarized light emitted from the emission surface of
On the display surface of the liquid crystal display element, about twice as large.
Large and small amount of light emitted to match each other
Characterized by at least two eccentric lenses
Polarization combining element. 2. The polarization combining device according to claim 1, wherein
The reflecting means is composed of two right-angle prisms.
The polarizing beam splitter and the right angle prism
The eccentric lens and the predetermined surfaces are optically connected to each other.
Bonded together to form a polarized beam.
The light incident on the splitter is emitted from the eccentric lens.
Before leaking,
Polarization combining element. 3. A light source for emitting non-polarized light, and at least
Also consists of one positive or negative power lens
Is, focusing of the indefinite polarized light emitted from the light source
A focusing lens system to be focused on and a focusing lens system focused by the focusing lens system.
The variable polarization light is incident and separated into P-polarized light and S-polarized light
And one of the polarized lights is emitted from the first emission surface.
And the other polarized light is emitted from the second emission surface,
At the first exit surface, the light exits from the first exit surface.
The area of the cross section of the polarized light is the display surface of the liquid crystal display device.
A polarizing beam splitter that is approximately 1/4 of the area of
Having at least a first and a second reflecting surface, wherein the first reflecting surface
The plane including the optical axis of the incident light and the optical axis of the reflected light with respect to the surface and the front
The optical axis of the incident light and the optical axis of the reflected light with respect to the second reflecting surface
Are orthogonal to each other, and the first reflecting surface
Angle of Incident Light to Light and Reflection to Second Reflective Surface
The first and the first are set so that the light reflection angles are 45 degrees, respectively.
And a second reflecting surface, and the polarizing beam splitter
The polarized light emitted from the second emission surface of the first
The light enters the reflecting surface and its polarization direction is
Polarization of the polarized light emitted from the first emission surface of the
Direction so as to be equal to the second reflecting surface.
Out through the exit surface, and at the exit surface,
Area of the cross section of the polarized light emitted through the emission surface
Is approximately ４ of the area of the display surface of the liquid crystal display element.
Reflection means and a first output of the polarizing beam splitter
The polarized light emitted from the surface and the emission surface of the reflection means
And the polarized light emitted from the
On the display surface of the crystal display element,
And at least emit so that they are synthesized in accordance with each other
Two eccentric lenses, and the
The liquid crystal table for displaying an image by transmitting polarized light
And a display element.
Place. 4. The liquid crystal display device according to claim 3,
The reflecting means is composed of two right-angle prisms.
The polarizing beam splitter and the right angle prism
The eccentric lens and the predetermined surfaces are optically connected to each other.
Bonded together to form a polarized beam.
The light incident on the splitter is emitted from the eccentric lens.
Before leaking,
Liquid crystal display device. 5. A liquid crystal display device according to claim 3 or 4.
In the liquid crystal display element, each micro lens is
Each is arranged to be equal to the pixel array, and each micro
The shape of the area where each lens shape corresponds to one pixel
(Square, rectangular, etc.)
Closely adhere to the transparent substrate on the side where the polarized light is
The focus of the chlorens is in or near the liquid crystal layer, respectively.
Arrange so that it is located beside and almost in the center of the pixel electrode
A liquid crystal display device characterized by comprising: 6. A liquid crystal display device according to claim 3 or 4.
In the liquid crystal display element, each micro lens is
Each is arranged to be equal to the pixel array, and each micro
The shape of the area where each lens shape corresponds to one pixel
(Square, rectangular, etc.)
Instead of a transparent substrate on the side where the polarized light is incident,
The focus of the icro lens is in each liquid crystal layer, and
Be arranged so that it is located almost at the center of the pixel electrode
A liquid crystal display device characterized by the above-mentioned. 7. The liquid crystal according to claim 3, 4, 5, or 6.
In a display device, a lens constituting the focusing lens system
Of at least one lens surface, at least one lens surface is non-
A liquid crystal display device comprising a spherical surface.