JPH09304759A - Liquid crystal display element and projection color liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a bright display image by effectively using both of their P polarization components and S polarization components related to dark red color and blue color components and performing light modulation processing among respective color components of light source light, and making the brightness of the light of red color and blue color components the same extent as the brightness of the brightest green component performed with the light modulation processing only for one side of the P polarization and S polarization. SOLUTION: Light source light being a parallel luminous flux of non- polarization is separated to P polarization light and S polarization light by a first polarizing beam splitter 8, and further, the P polarization light is converted into the S polarization by a first λ/2 plate 9a, and the first, second S polarization are formed. Then, related to the light of the red color and blue color of a dark wavelength band, the light modulation processing are performed for their first S polarization components and second S polarization components by respective liquid crystal display elements 3RB1 , 3RB2 , and transmission light from both liquid crystal display elements 3RB1 , 3RB2 , are synthesized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a projection type color liquid crystal display device, and more particularly to a projection type color liquid crystal display device using a transmission type liquid crystal display panel, wherein the P polarization component and S polarization of the light source light are used. The present invention relates to a structure for efficiently using components.

[0002]

2. Description of the Related Art A projection television using a liquid crystal display element has been developed as an alternative to the conventional method of projecting an image displayed on a CRT on a screen. As a projection type color image display system using such a liquid crystal display element, as disclosed in Japanese Patent Application Laid-Open No. 3-53221, three liquid crystal display elements corresponding to three primary colors for color image display are used. A three-panel type projection type color image display device used for one sheet is well known.

FIG. 6 shows an example of the construction of such a three-plate projection type color image display device. In the figure, 2
00 is 3 corresponding to each of the three primary colors required for color display
This is a three-plate projection type color liquid crystal display device having two liquid crystal display elements 3R, 3B and 3G.

In this liquid crystal display device 200, the collimated light emitted from the lamp light source 1 is converted into red light by the dichroic mirrors 2G and 2R which selectively reflect green light and red light, respectively.
The lights are separated into three primary colors of green and blue, and the respective lights are incident on the respective liquid crystal display elements 3R, 3G, 3B corresponding to the respective colors.

Here, each liquid crystal display element 3R, 3G, 3B
Is composed of a microlens array and a liquid crystal display panel. The parallel light incident on the liquid crystal display elements 3R, 3G, 3B is condensed by the microlens array on the picture elements constituting each liquid crystal display element. It

The light transmitted through the respective liquid crystal display elements reaches the dichroic mirrors 5R and 5B which selectively reflect the red and blue lights through the field lens 4, and the light is optically reflected by the respective dichroic mirrors. Overlaid. The image of the three primary colors formed in this manner is enlarged and projected on the screen 7 by the projection lens 6.

Reference numeral 61 is a reflection mirror that reflects the green light from the dichroic mirror 2G to the liquid crystal display element 3G side, and 62 is a reflection mirror that reflects the transmitted light of the liquid crystal display element 3B to the dichroic mirror 5B side.

FIG. 4 is a schematic sectional view showing the detailed structure of the liquid crystal display panel. The liquid crystal display panel 14 has a structure in which a liquid crystal layer 38 is sandwiched between a pair of substrates 17 and 16 arranged so as to face each other. A plurality of picture element electrodes 35 are arranged in a matrix on the surface of one of the two substrates (hereinafter, also referred to as an active matrix substrate) 17. Further, on the substrate 17, a signal line 29 is provided corresponding to each column (or each row) of the picture element electrodes, and a gate line is provided corresponding to each row (or each column) of the picture element electrodes. Has been. Further, on the substrate 17, a thin film transistor (TFT) 27 and an auxiliary capacitor 28 for driving each pixel electrode 35 are provided, and the gate 30 of each TFT 27 is connected to a corresponding gate line. The sources are connected to the corresponding signal lines 29. The drain of the TFT is connected to the corresponding pixel electrode 35 and the corresponding auxiliary capacitor 28.
Is connected to one of the electrodes. A potential at the same level as that of a counter electrode described later is applied to the other electrode of the auxiliary capacitance 28. 27a is the above TF
A semiconductor layer forming T27, and 27b is a gate insulating film forming the TFT 27.

Further, the active matrix substrate 17
The counter electrode 33 and the light shielding film 34 are sequentially formed on the inner surface of the counter substrate 16 facing each other via the liquid crystal layer 38, and the light shielding film 34 has an opening (a pixel opening) at a position facing the pixel electrode 35. ) 36 are formed. Here, both the substrates 1
As the liquid crystal layer 38 sealed between 7 and 16, for example, a twisted nematic liquid crystal layer is used. Further, here, one picture element is the picture element electrode 3
5. Liquid crystal part of the liquid crystal layer corresponding to the picture element electrode, TFT
27, auxiliary capacitance 28 and the like.

As shown in FIG. 5, the microlens array has a hexagonal microlens 10 in which outer peripheral portions of spherical lenses are fused with each other by using an ion exchange method.
In this example, a plurality of a's are produced, and the pitch of the lens array is the same as the pitch of the picture elements of the liquid crystal display panel. Here, the relative positional relationship between the picture element array and the microlens array is as shown in FIG.

That is, in the liquid crystal display panel 14, the arrangement of the picture elements is such that the picture elements 11a are arranged in a checkerboard pattern, and the odd or even numbered columns are compared with the even or odd numbered columns. The hexagonal microlenses 10a are arranged so as to be shifted by half the size, and the center of the optical axis of the lens is aligned with the center of the corresponding picture element. It should be noted that in FIG. 5, 11 is the entire area occupied by the picture element electrodes, TFTs, auxiliary capacitors, etc. corresponding to one picture element 11a.
Is a portion corresponding to the opening 36 of the light shielding film in this entire region.

[0012]

However, in the conventional liquid crystal display device, since the light emitted from the light source 1 is directly incident on the liquid crystal display panel as described above, the brightness of the light from the light source is reduced. There is a problem that the brightness of the display image becomes extremely low as compared with.

That is, the light emitted from the light source is non-polarized light, and the liquid crystal display panel on which the light is incident has a polarizing plate on the incident surface and the emitting surface. Therefore, the liquid crystal display panel can use only linearly polarized light that has passed through the polarizing plate on the incident surface side. For example, even if the incident side polarization plate is in a perfect ideal state, only 50% of the light from the light source can be used for display on the liquid crystal display panel at the maximum.

Moreover, the intensities of the red, green and blue colors of the light source light are rarely equal, and for example,
In metal halide lamps, light in the green wavelength range tends to be brightest and light in the red or blue wavelength range tends to be dark. Therefore, in the conventional liquid crystal display device, in order to express the color display image on the screen in a natural color, the brightness of light of each color of red, blue, and green is set to the brightness of the light of the darkest color. The light of the other colors is adjusted to have the same brightness, and the light of the other two bright colors is not effectively used, and a part of the light is wasted.

The present invention has been made in order to solve the above-mentioned conventional problems, and includes three wavelength bands included in the light source, which are necessary for displaying a color image, that is, red, blue and green light. For the light in the dark wavelength range, the brightness is
An object of the present invention is to obtain a liquid crystal display element and a projection type color liquid crystal display device that can align light in the brightest wavelength region by utilizing P-polarized light component and S-polarized light component of light source light.

[0016]

A liquid crystal display device according to the present invention (claim 1) is provided so as to correspond to first and second wavelength bands of three wavelength bands required for color image display. , Receiving the display signal corresponding to each wavelength range,
First and second color display electrodes for driving the liquid crystal forming the picture element, and luminous fluxes of the first and second wavelength ranges that are incident at different angles are supplied to the respective wavelength ranges forming the picture element. And a microlens array for focusing light on a corresponding liquid crystal part.

The microlens array is composed of a plurality of microlenses corresponding to a plurality of adjacent picture elements, and the luminous fluxes of the first and second wavelength ranges incident at the different angles are
Each microlens is configured to enter the liquid crystal portion of the picture element corresponding to each wavelength range. Thereby, the above object is achieved.

A projection type color liquid crystal display device according to the present invention (claim 2) separates a parallel light flux emitted from a predetermined light source into P-polarized light and S-polarized light, and at least one of the both polarized light. Luminous flux processing means for rotating the polarization plane to create first and second linearly polarized light with uniform polarization planes, and first and second wavelength ranges of three wavelength ranges necessary for color image display Corresponding to the first liquid crystal display element for subjecting the light fluxes of the first and second wavelength bands in the first linearly polarized light to optical modulation processing, and a first liquid crystal display element of the three wavelength bands. 1
And a second liquid crystal display element which is provided corresponding to the second wavelength band and which performs light modulation processing on the light fluxes of the first and second wavelength bands in the second linearly polarized light. .

Further, this liquid crystal display device is provided corresponding to the third wavelength band of the three wavelength bands, and the luminous flux of the third wavelength band in one of the first and second linearly polarized lights. And a third liquid crystal display element that performs a light modulation process on the liquid crystal display element, and a light flux that is disposed so as to be positioned on the light emission side of each of the liquid crystal display elements and that passes through the liquid crystal display element on the display screen. Equipped with an optical system that synthesizes a color image by projecting
The first and second liquid crystal display elements are configured so that the light fluxes having the first and second wavelength ranges are made incident in mutually different directions. Thereby, the above object is achieved.

The present invention (claim 3) provides the projection type color liquid crystal display device according to claim 2, wherein the first and second
The liquid crystal display element of is provided so as to correspond to the first and second wavelength ranges of the three wavelength ranges necessary for color image display, and receives the display signals corresponding to the respective wavelength ranges to display the picture elements. First and second color display electrodes that drive the liquid crystals that compose the liquid crystal, and liquid crystals corresponding to the respective wavelength bands that compose the picture element, for the luminous fluxes of the first and second wavelength bands that are incident at different angles. A microlens array for condensing light on a part, the microlens array being composed of a plurality of microlenses corresponding to a plurality of adjacent picture elements, and the first and second incident light beams at different angles. The light flux in the wavelength range is configured to enter the liquid crystal portion of the picture element corresponding to each wavelength range by each microlens.

According to the present invention (claim 4), in the projection type color liquid crystal display device according to claim 3, a picture element corresponding to the first wavelength range and a picture element corresponding to the second wavelength range are provided. Are arranged in a matrix as a whole so as to be alternately arranged in the vertical direction and the horizontal direction, and each microlens constituting the microlens array corresponds to two picture elements adjacent in the vertical direction or the horizontal direction. The optical axis center is located at the central portion between the two picture elements.

According to a fifth aspect of the present invention, in the projection type color liquid crystal display device according to the third aspect, the first picture element corresponding to the first wavelength range and the second wavelength range correspond to the first picture element. The second picture element is arranged such that a picture element row composed of the first picture element and a picture element row composed of the second picture element are alternately arranged, and the microlens array is configured. The respective microlenses are arranged so as to correspond to the adjacent first and second picture elements and the optical axis center is located at the central portion between the adjacent first and second picture elements.

According to a sixth aspect of the present invention, in the projection type color liquid crystal display device according to the third aspect, the first picture element corresponding to the first wavelength range and the second wavelength range correspond to the first picture element. The second picture element is arranged such that a first picture element row composed of the first picture element and a second picture element row composed of the second picture element are alternately located, and Each of the microlenses forming the microlens array corresponds to the adjacent first and second picture element rows, and the optical axis center is located at the central portion between the adjacent first and second picture element rows. The lenticular lens has a substantially semicircular cross section.

According to a seventh aspect of the present invention, in the projection type liquid crystal display device according to the third aspect, the third liquid crystal display element is provided with a third wavelength band among three wavelength bands necessary for color image display. A color display electrode that is provided corresponding to each wavelength region, receives a display signal corresponding to the wavelength region, and drives a liquid crystal that constitutes a pixel, and that is provided corresponding to each pixel, And a microlens array made up of microlenses for condensing the light flux corresponding to the above on the liquid crystal part constituting the picture element.

The operation of the present invention will be described below. According to the present invention (Claim 1), the display signals corresponding to the respective wavelength ranges corresponding to the first and second wavelength ranges of the three wavelength ranges necessary for the color image display are received, and the picture elements are received. Comprising the first and second color display electrodes for driving the liquid crystal constituting the above, and the luminous fluxes of the first and second wavelength bands incident at different angles constitute the picture element by the microlens array, respectively. Since the light is condensed on the liquid crystal portion corresponding to the wavelength range of, the light modulation processing can be performed on the light fluxes of the two wavelength ranges by one liquid crystal display element. Therefore, by using two such liquid crystal display elements, the P of the light source light can be reduced in the first and second wavelength ranges.
By effectively utilizing both the polarized light and the S-polarized light without waste, the color display image in the projection type color liquid crystal display device can be made very bright.

In the present invention (claims 2 and 3), the parallel light flux emitted from the predetermined light source is separated into P-polarized light and S-polarized light, and at least one polarization plane of the both polarized light is rotated. Then, the first and second linearly polarized lights having the same plane of polarization are created, and the light of the first and second wavelength bands out of the three wavelength bands necessary for color image display is Separate first and second linearly polarized light and second linearly polarized light
Since the light modulation processing is performed by the liquid crystal display element of 1 and the transmitted light from the both liquid crystal display elements is combined, the brightness of the light in the first and second wavelength ranges of the above three wavelength ranges. Can be doubled.

That is, for the light in the first and second wavelength regions of the light source light, both the P-polarized component and the S-polarized component of the light source light can be effectively used. As a result, the brightness of the light in the dark wavelength range can be made approximately the same as the brightness of the light in the brightest wavelength range in one of the P-polarized light and the S-polarized light of the light source light, resulting in a very bright color. An image can be formed.

In the present invention (claim 4), the picture elements corresponding to the first and second wavelength regions are arranged in a matrix as a whole so as to be alternately positioned in the vertical and horizontal directions, Moreover, since the microlens array is configured such that the microlenses corresponding to two vertically adjacent picture elements are arranged in a zigzag pattern, the diagonal line display on the display screen is relatively smooth. it can.

In the present invention (Claim 5), each picture element corresponding to the first and second wavelength ranges is composed of a picture element sequence consisting of the first picture element and the second picture element. The pixel rows are arranged so as to alternate with each other, and each microlens of the microlens array has a size including the adjacent first and second picture elements, and the adjacent first and second pictures are arranged. Since the optical axis center is located at the center of the space between the elements, the vertical and horizontal line display on the display screen can be made relatively smooth.

In the present invention (claim 6), each picture element corresponding to the first and second wavelength ranges is defined by the first and second picture elements.
The first and second picture element rows each of which is composed of the picture element of (1) are arranged alternately, and each microlens of the microlens array includes the first and second picture element rows adjacent to each other. Since it is composed of a lenticular lens having a substantially semicircular cross section whose optical axis center is located in the central portion between the adjacent first and second picture element rows, the horizontal or vertical line display in the display image is relatively smooth. Can be Further, since the vertically long lenticular lens, which constitutes the microlens and in which the power of the condensed light is linearly distributed in a certain direction, is larger than the quadrangular microlens, it is relatively easy to manufacture, and its manufacturing cost is also high. Become cheap.

In the present invention (Claim 7), the third liquid crystal display element receives the display signal corresponding to the third wavelength region out of the three wavelength regions required for color image display, and displays the image. It has a color display electrode for driving the liquid crystal forming the element, and a light flux corresponding to the wavelength range is generated by a microlens.
Since the light is condensed on the liquid crystal portion forming each picture element, all the light incident on the liquid crystal display element can be condensed on each picture element even if the aperture ratio of each picture element is small. This makes it possible to brighten the light of the color that is the basis of the brightness and improve the light utilization efficiency of the entire device.

[0032]

1 is a schematic diagram for explaining the configuration of a projection type color liquid crystal display device according to an embodiment of the present invention. FIG. 1 (a) shows a light source light (non-polarized light). The passing path of the P-polarized light (first S-polarized light) separated from
In (b), a passage path of S-polarized light (second S-polarized light) separated from the light source light (non-polarized light) is shown.

In the figure, 100 is 3 according to the present embodiment.
In a plate-type projection color liquid crystal display device, a light source 1 for emitting a parallel light flux of unpolarized light, a parallel light flux is separated into P-polarized light and S-polarized light, and a polarization plane of the P-polarized light is rotated. , Two linearly polarized lights with the same plane of polarization, that is, the first and second S
And a light flux processing means for generating polarized light. Here, the light flux processing means includes a first polarization beam splitter 8 for separating the parallel light flux emitted from the light source 1 into P-polarized light and S-polarized light, and P-polarized light transmitted through the polarization beam splitter 8. Is converted into S-polarized light (first S-polarized light) with a first λ / 2 plate 9a. A lamp light source such as a metal halide lamp is used as the light source 1. In this lamp light source, the green component is the brightest among the color components of the emitted light, and the blue component and the red component are
It is darker than the green component.

Further, the liquid crystal display device 100 is provided with three liquid crystals, which are provided corresponding to required ones of the three primary colors necessary for color image display, and which perform light modulation processing on light fluxes of corresponding colors. It has display elements 3G, 3RB ₁ and 3RB ₂ .

The liquid crystal display element 3G and the first λ / 2 plate 9
A dichroic mirror 2G that selectively reflects the green component of the first S-polarized light is disposed between the a and the a. On the light emission side of this dichroic mirror 2G, the red component of the first S-polarized light that has passed through this mirror 2G is reflected to the liquid crystal display element 3RB ₁ side and the blue component of the first S-polarized light is passed. A dichroic mirror 2R leading to the liquid crystal display element 3RB ₂ is arranged. The dichroic mirror 2R reflects the red component of the second S-polarized light to the liquid crystal display element 3RB ₂ side, passes the blue and green components thereof, and guides it to the liquid crystal display element 3RB ₁ . .

The above liquid crystal display element (third liquid crystal display element)
3G corresponds to the light flux of the green component of the light source light, and performs light modulation processing on the light flux of the green component of the first S-polarized light. The liquid crystal display element (first liquid crystal display element) 3RB ₁ corresponds to the luminous fluxes of the red component and the blue component of the light source light, and the red component of the first S polarized light and the second S polarized light The light modulation processing is performed on the light fluxes of the blue and green components of the light. Further, the liquid crystal display element (second liquid crystal display element) RB ₂ corresponds to the luminous fluxes of the red component and the blue component of the light source light, and the blue component and the second S polarized light of the first S polarized light. The light modulation processing is performed on the light flux of the red component of the light.

Further, the liquid crystal display device 100 is arranged so as to be positioned on the light emission side of the liquid crystal display elements 3G, 3RB ₁ and 3RB ₂ , and the luminous flux transmitted through the liquid crystal display elements is displayed on the screen ( It is provided with an optical system for superimposing on the display screen 7 to synthesize a color image. here,
The optical system includes the liquid crystal display elements 3G, 3RB ₁ , 3
Each field lens 4 arranged on the light emitting surface side of RB _2.
And dichroic mirrors 5R, 10R for selectively reflecting red light for combining light transmitted through the liquid crystal display elements 3G, 3RB ₁ , 3RB ₂ and the field lens 4.
And dichroic mirrors 5B and 10B that selectively reflect blue light.

The dichroic mirror 5R synthesizes the green component of the first S-polarized light modulated by the liquid crystal display element 3G and the red component of the first S-polarized light modulated by the liquid crystal display element 3RB _1. And is arranged on the emission side of each field lens 4 corresponding to each liquid crystal display element 3G, 3RB ₁ .

Further, the dichroic mirror 5B is
The green and red components of the first S-polarized light combined by the dichroic mirror 5R and the liquid crystal display element 3R
This is for synthesizing the blue component of the first S-polarized light modulated by B ₂ , and is the light of the field lens 4 on the light emitting side of the dichroic mirror 5R and corresponding to each liquid crystal display element 3RB _2. It is located on the exit side.

The above dichroic mirror 10B
Is for separating the green component and the blue component of the second S-polarized light, which is modulated by the liquid crystal display element 3RB ₁ and transmitted through the dichroic mirror 5R, and is disposed on the light emission side of the dichroic mirror 5R. Has been done.

The above dichroic mirror 10R
Is the blue component of the second S-polarized light reflected by the dichroic mirror 10B and the liquid crystal display element 3RB.
It is combined with the red component of the second S-polarized light that has been modulated by ₂ and transmitted through the dichroic mirror 5B, and is arranged on the light emission side of the dichroic mirrors 10B and 5R.

The optical system is arranged on the light emitting side of the dichroic mirror 10R, and converts the second S-polarized light in which the blue component and the red component are combined by the dichroic mirror 10R into P-polarized light. 2 λ / 2 plate 9
b, and a second polarization beam splitter 11 that combines the P-polarized light from the second λ / 2 plate 9b and the first S-polarized light from the dichroic mirror 5B.

A projection lens 6 is arranged on the light emitting side of the second polarization beam splitter 11 of this optical system, and the P polarization light and the S polarization light are combined by the second polarization beam splitter 11. The projected light beam is projected onto the screen 7 by the projection lens 6, and the screen 7
A color image corresponding to the video signal is displayed.

Further, in the above optical system, between the first polarization beam splitter 8 and the dichroic mirror 2R,
First and second reflection mirrors 51 and 52 that reflect the S-polarized light (second S-polarized light) separated from the light source light by the beam splitter 8 and guide it to the dichroic mirror 2R.
Is arranged. The dichroic mirror 2 is provided between the dichroic mirror 2G and the liquid crystal display element 3G.
A reflection mirror 53 for guiding the green component light of the first S-polarized light separated by G to the liquid crystal display element 3G is arranged.

On the light emitting side of the field lens 4 corresponding to the liquid crystal display element 3RB ₂ , the liquid crystal display element 3RB is provided.
₂ in optically modulated and the optical light and the red component of the second S-polarized blue component of the first S-polarized light, the reflecting mirror 54 for reflecting the respective dichroic mirrors 5B and 10R side It is provided. On the light emitting side of the dichroic mirror 5B, a reflecting mirror that reflects the first S-polarized light in which the red and green components and the blue component are combined by the mirror 5B toward the second polarization beam splitter 11 side. 55 are arranged.

Then, the liquid crystal display device 100 of the present embodiment.
Then, in the light source 1, the parallel light flux emitted from the light source is
The emission direction of light is set so as to form a predetermined angle (−θ) with respect to the optical axis of the optical system, that is, the optical axis Lg passing through the central axis of each optical member in the optical system. The dichroic mirrors 2G, 5R, and 5B are positioned so as to form a constant angle (45 ° −θ / 2) with respect to the optical axis Lg of the optical system (see FIG. 1A). The dichroic mirrors 10B and 10R are positioned so as to form a constant angle (45 ° + θ / 2) with respect to the optical axis Lg (see FIG. 1B) of the optical system. Other dichroic mirror 2R and reflection mirror 51,
52, 53, 54 and 55 are positioned so as to form 45 ° with respect to the optical axis Lg of the optical system.

As a result, in the above optical system, the red component light of the first S-polarized light makes an angle (+ θ) with the optical axis Lg of the optical system in the _first liquid crystal display element 3RB _1. Thus, the blue and green components of the second S-polarized light are incident so as to form an angle (−θ) with respect to the optical axis Lg of the optical system. In addition, the second liquid crystal display device 3RB
_The light of the blue component of the first S-polarized light is incident on 2 so as to make an angle (−θ) with respect to the optical axis Lg of the optical system,
The red component of the polarized light is made incident at an angle (+ θ) with respect to the optical axis Lg of the optical system. Further, in this optical system, the green component light of the first S-polarized light is transmitted to the third liquid crystal display element 3G by the optical axis L of the optical system.
The light of the green component of the second S-polarized light that enters in parallel with g is transmitted through the dichroic mirror 10B and is discharged from the optical system.

As shown in FIG. 2, the first and second liquid crystal display elements 3RB ₁ and 3RB ₂ are arranged on the liquid crystal display panel 14a and on the light incident surface side and the light emitting surface side thereof. The polarizing plates 12 and 18 and the microlens array 13a arranged on the light incident surface of the liquid crystal display panel 14a. The detailed sectional structure of the liquid crystal display panel 14a is the same as that shown in FIG.

The microlens array 13a is also used.
Is a method in which a plurality of quadrangular microlenses 13a _{1 in} which the outer peripheral portions of spherical lenses are fused to each other are created by using an ion exchange method, and the relative position between the pixel array and the microlens array. The relationship is as shown in FIG.

That is, in the liquid crystal display panel 14a,
The square picture elements 15R corresponding to red and the square picture elements 15B corresponding to blue are arranged in a matrix as a whole so as to be alternately positioned in the vertical direction and the horizontal direction of the paper surface. Further, in the microlens array 13, each microlens 13a constituting the microlens array 13 is formed in a size including two picture elements adjacent to each other in the vertical direction of the paper surface, and the optical axis is formed in the central portion between the two picture elements. The center is located.

As shown in FIG. 7, the third liquid crystal display element 3G includes a liquid crystal display panel 14b, polarizing plates 12 and 18 arranged on the light incident surface side and the light emitting surface side thereof, and the above liquid crystal. It is composed of a microlens array 13b arranged on the light incident surface of the display panel 14b.

The microlens array 13b is formed by forming a plurality of quadrangular microlenses 13b _{1 in} which outer peripheral portions of spherical lenses are fused with each other by using an ion exchange method. As for the relative positional relationship with the lens array, as shown in FIG. 8, the picture elements here and the microlenses have a one-to-one correspondence.

That is, in the liquid crystal display panel 14b,
The picture elements 15G are arranged in a matrix, and in the microlens array 13b, the microlenses 13b ₁
Are arranged in a matrix so as to correspond to the respective picture elements 15G.

By doing so, even if the aperture ratio of each picture element 15G in the liquid crystal display panel 14b is small, it is possible to condense all the light flux incident on the microlens surface and take it into the corresponding picture element. The green light, which is the reference for the brightness in this embodiment, becomes brighter, and the light utilization efficiency can be improved as a whole.

However, the liquid crystal display element 3G may not include the microlens array if the aperture ratio of each picture element is sufficiently large. By doing so, it is possible to reduce the cost by reducing the microlenses.

Further, in the liquid crystal display device 100, it is desirable that the total number of picture elements 15R, 15G, 15B corresponding to each color in all the liquid crystal display elements 3G, 3RB ₁ , 3RB ₂ be the same.

For example, each of the red picture element 15R and the blue picture element 15B of the liquid crystal display element 3RB ₁ has n picture elements, and the red picture element 15 of the liquid crystal display element 3RB ₂ is n.
When each of the R and blue picture elements 15B has n picture elements, it is desirable that the number of picture elements of the green picture element 15G of the liquid crystal display element 3G is 2n.

The method of superimposing the respective picture element images on the screen 7 is, for example, ₁ of the liquid crystal display element 3RB ₁ .
The image of one picture element 15B or 15R of the liquid crystal display element 3RB ₂ may be superposed on the image of one picture element 15R or 15B, and further the one picture element 15G of the liquid crystal display element 3G may be superposed.

Next, a method of setting the angle θ formed by the parallel light beam emitted from the light source and the optical axis of the optical system will be briefly described.

For example, the liquid crystal display elements 3RB ₁ , 3RB ₂ ,
The number of 3G picture elements is 480 x 640 (vertical 480).
640 pieces), which corresponds to a 1.5-inch panel, and the distance between the centers of adjacent picture elements is 47.5 μm.
The focal lengths of the microlens arrays 13a and 13b are the same as the thickness of the counter substrate 36 and are 0.7 mm (refractive index n = 1.
53). In addition, this distance 0.7 mm is 0.458 mm (= 0.7 mm /
1.53).

In this case, the first and second liquid crystal display elements 3
In RB ₁ and 3RB ₂ , the chief ray of the parallel light flux incident on the red or blue pixel aperture on the light incident surface side of the liquid crystal display panel is θ = ± with respect to the normal direction of the light incident surface. ta
n ⁻¹ (23.75 / 458) = ± 3.0 °.

Next, the operation will be described. Lamp light source 1
From, a non-polarized parallel light beam is emitted at an angle (−θ) with respect to the optical axis Lg of the optical system, and when this is incident on the polarization beam splitter 8, the P-polarized component light of the parallel light beam is emitted. The light of the S-polarized component of the parallel light flux that has passed through the polarization beam splitter 8 is reflected by the polarization beam splitter 8, and thus the P-polarized light and the S-polarized light of the parallel light flux are separated. Here, the light source light from the lamp light source has the brightest green component among the color components.

First, the P-polarized light transmitted through the polarization beam splitter 8 has a first λ as shown in FIG.
It is converted into S-polarized light (first S-polarized light) by the / 2 plate 9a. The first S-polarized light is reflected by the dichroic mirror 2G that selectively reflects green light and the dichroic mirror 2R that selectively reflects red light.
It is separated into green, red and blue lights.

That is, the brightest green light of the first S-polarized light is reflected by the dichroic mirror 2G while being deviated from the optical axis Lg, and is further reflected by the reflecting mirror 5.
At 3, the light is reflected so as to match the optical axis Lg, and enters the liquid crystal display element 3G perpendicularly to the incident surface.

Of the first S-polarized light, the red component light that has passed through the dichroic mirror 2G is reflected by the dichroic mirror 2R while being displaced from the optical axis Lg, and the liquid crystal display element is displayed. The light is incident on the incident surface of 3RB ₁ slightly obliquely so as to form an angle (+ θ) with respect to the optical axis Lg.

Further, of the first S-polarized light, the blue component light that has passed through the dichroic mirror 2R is incident on the incident surface of the liquid crystal display element 3RB ₂ at an angle (−θ) with respect to the optical axis Lg. It is incident at a slight angle so that

The liquid crystal display elements 3G, 3RB ₁ , 3
The light transmitted through RB ₂ is combined by the field lens 4 and the dichroic mirrors 5R, 5B, reflected by the reflection mirror 55, and reaches the second polarization beam splitter 11.
Here, the light is further reflected and projected on the screen 7 via the projection lens 6.

On the other hand, the S-polarized light (second S-polarized light) reflected by the first polarization beam splitter 8 is as shown in FIG.
As shown in (b), the dichroic mirror 2R reflected by the reflection mirrors 51 and 52 bypasses the dichroic mirror 2G to reach the dichroic mirror 2R, and the dichroic mirror 2R that selectively reflects the red light causes the second S. The polarized light is split into its green and blue component light and its red component light.

That is, the second S-polarized light is reflected by the first and second reflecting mirrors 51 and 52 while being displaced from the optical axis Lg of the optical system, and is reflected by the dichroic mirror 2R on the optical axis Lg. It is incident so as to form an angle (-θ) with respect to. Here, the light of the red component of the second S-polarized light is reflected while being shifted from the optical axis Lg, and the liquid crystal display element 3RB ₂ has an angle (+) with respect to the optical axis Lg.
The light is incident at a slight angle with respect to the incident surface so as to form θ).

Further, the green and blue component lights of the second S-polarized light transmitted through the dichroic mirror 2R are
The liquid crystal display element 3RB ₂ is slightly obliquely incident on the incident surface so as to form an angle (−θ) with the optical axis Lg.

Then, each of the liquid crystal display elements 3RB ₁ , 3
The light transmitted through RB ₂ is combined by the field lens 4, the dichroic mirror 10B that selectively reflects blue light, and the dichroic mirror 10R that selectively reflects red light.

That is, the green and blue component lights of the second S-polarized light which have passed through the respective liquid crystal display elements 3RB ₁ pass through the dichroic mirror 5R and enter the dichroic mirror 10B at an angle with respect to the optical axis Lg. It is incident so as to form (-θ). Here, the green component light of the second S-polarized light passes through the dichroic mirror 10B and exits the optical system. Further, the light of the blue component of the second S-polarized light is arranged so that the dichroic mirror 10B forms an angle (45 ° + θ) with respect to the optical axis Lg. The light is reflected so as to match the optical axis Lg and enters the dichroic mirror 10R.

The red component light of the second S-polarized light that has passed through the second liquid crystal display element 3RB ₂ is reflected by the reflection mirror 54 so as to match the optical axis Lg, and passes through the dichroic mirror 5B. Then dichroic mirror 10
It is incident on R.

The dichroic mirror 10R transmits the blue component light of the second S-polarized light that coincides with the optical axis Lg and reflects the red component light of the second S-polarized light that coincides with the optical axis Lg. So, this dichroic mirror 10R
From, the blue component light and the red component light of the second S-polarized light are combined and emitted.

Then, this second S-polarized light has a second λ
Is converted into P-polarized light by passing through the / 2 plate 9b,
It passes through the second polarization beam splitter 11 and is projected on the screen 7 via the projection lens 6.

As a result, in the second polarization beam splitter 11, the first S-polarized light (P-polarized component of the light source light) in which the green, red and blue components are combined, and the red and blue components are combined. The P-polarized light (S-polarized light component of the light source light) is combined, and the brightness of the dark red and blue components of each color component of the light source light is doubled, and the respective brightnesses are the respective color components of the light source light. Of these, the brightness is the same as that of the brightest green component, and a bright color image is formed on the screen 7.

As described above, in the present embodiment, the source light, which is a non-polarized parallel light flux, is converted into P by the polarization beam splitter 8.
The polarized light and the S-polarized light are separated, and the P-polarized light is further divided by λ.
/ 2 plate 9a converts the light into S-polarized light to create first and second S-polarized light, and the red and blue light in the dark wavelength range of the light source light has its first S-polarized component. And separate liquid crystal display elements 3RB ₁ and 3RB for the second S-polarized component
Since the light modulation processing is performed by RB ₂ and the transmitted light from the both liquid crystal display elements is combined, the brightness of the dark red and blue components of each color component of the light source light can be doubled. it can.

That is, when light modulation processing is performed on the red component light and the blue component light of the light source light by the liquid crystal display elements corresponding to the respective colors of light, the polarization plate on the incident side of the liquid crystal display element. Due to this, one of the P-polarized component and the S-polarized component of the light source light is blocked and cannot be used, whereas in the present embodiment, among the color components of the light source light,
For the dark red and blue components, its P-polarized component and S
Both polarization components can be effectively used. As a result, the brightness of the red and blue components of the light can be changed to the P-polarized light and S of the light source light.
The brightness of the brightest green component, which has been subjected to the light modulation processing on only one of the polarized lights, can be made approximately the same, and a bright color image can be formed on the screen 7.

In the conventional liquid crystal display element, the polarized light not used is the polarizing plate 12 on the front surface of the liquid crystal display panel.
However, in the present invention, unnecessary S-polarized light corresponding to the green color of the light source light is discharged out of the optical system, and P-polarized light and S-polarized light of the source light red and blue are emitted. Since light is used together, temperature rise in the device due to light from the light source can be suppressed. For this reason, the burden on the cooling device and the like is reduced, power consumption can be reduced, and cost can be reduced.

Further, in the present embodiment, the liquid crystal display element for subjecting the red light and the blue light to the light modulation processing has the pixels corresponding to the red and the blue and the red light incident at different angles. Since a liquid crystal display element 3RB ₁ is used, a P-polarized component of the light source light (first S-polarized light) is used because a microlens for condensing light and blue light into corresponding color picture elements is used. The red light and the S-polarized component of the light source light (second S-polarized light) are subjected to light modulation processing, and the liquid crystal display element 3RB ₂ causes the P-polarized component of the light source light (first S-polarized light). Of the blue light and the red light of the S-polarized component (second S-polarized light) of the light source light can be subjected to light modulation processing.
In other words, four lights, that is, the red and blue lights of the first S-polarized light and the red and blue lights of the second S-polarized light can be processed by the two liquid crystal display elements, and the high brightness of the display image can be obtained. It is possible to prevent the projection type color liquid crystal display device from increasing in size due to the increase in size.

Further, the liquid crystal display elements 3RB ₁ and 3RB ₂
Then, the optical axis L of the optical system is added to the microlens array 13a.
With respect to g, the focused spot of red light incident at + θ ° or −θ ° is −θ ° or + on the red pixel 15R.
The focused spot of blue light incident at θ ° is the blue pixel 15B.
Since it is formed above (for the sake of explanation, only the principal ray of the light flux is displayed in FIG. 2), the two colors incident on the microlens surface even if the aperture ratio of each picture element in the liquid crystal display element is small. The light fluxes can be separated and collected and taken into the corresponding picture elements, and the light utilization efficiency is high.

Furthermore, the liquid crystal display elements 3RB ₁ and 3R
In the B ₂ liquid crystal display panel 14, red picture elements 15R and blue picture elements 15B are arranged in a matrix as a whole so as to be alternately arranged in the vertical direction and the horizontal direction, and the microlens array 13a is further arranged in the vertical direction. Since the microlenses 13a corresponding to the two picture elements adjacent to each other in the direction are arranged in a zigzag pattern, there is an effect that the diagonal line display in the display image becomes comparatively smooth.

In the above embodiment, the liquid crystal display element 3
The positional relationship between the picture element array and the microlens array in RB ₁ and 3RB ₂ is shown in FIG. 3 (a), but the positional relationship is not limited to that shown in FIG. 3 (a). .

For example, the positional relationship between the pixel array and the microlens array in the liquid crystal display elements 3RB ₁ and 3RB ₂ may be as shown in FIG. 3 (b).

That is, the square picture element 15 corresponding to red
And R, a picture element 15b of the square corresponding to blue, and the pixel columns 15R _L consisting of the red picture element 15R, so that the picture element columns 15B _L consisting of the blue picture element 15B is positioned alternately Each of the microlenses 13a ₁ that are arranged to form the microlens array is connected to the adjacent red and blue picture elements 15
The size may include R and 15B, and the optical axis center may be located at the central portion between the adjacent red and blue picture elements 15R and 15B.

By taking such a positional relationship between the picture element array and the microlens array, there is an effect that horizontal or vertical line display in the display image can be comparatively smooth.

The positional relationship between the pixel array and the microlens array in the liquid crystal display elements 3RB ₁ and 3RB ₂ may be as shown in FIG. 3 (c).

That is, the square picture element 15 corresponding to red
And R, a picture element 15b of the square corresponding to blue, and the pixel columns 15R _L consisting of the red picture element 15R, so that the picture element columns 15B _L consisting of the blue picture element 15B is positioned alternately The respective microlenses 13a ₂ in the microlens array are arranged so that adjacent red and blue picture element columns 15 are arranged.
R _L, encompasses 15B _L, and said adjacent red and blue picture element row 15R _L, the center of the optical axis in the center portion between 15B _L is located, up and down direction only a substantially a half of light condensing effect It may be composed of a circular lenticular lens.

By taking such a positional relationship between the picture element array and the microlens array, there is an effect that the horizontal or vertical line display in the display image becomes comparatively smooth. Further, since the vertically long lenticular lens in which the power of the condensed light is linearly distributed in a certain direction is larger than the above-mentioned quadrangular microlens, it is relatively easy to manufacture, and the cost is reduced.

Further, in the above embodiment, the case where the green component of the light source light is the brightest has been described as an example, but the characteristics of the light source used are not limited to this. In short, light of the brightest color of the light source is used. The light flux corresponding to the P-polarized light and the light flux corresponding to the S-polarized light of the light source may be incident on the two liquid crystal display elements corresponding to light of colors other than the above at an angle of ± θ.

[0091]

As described above, according to the liquid crystal display element of the present invention (Claim 1), the liquid crystal forming the picture element is driven by receiving the display signals corresponding to the first and second wavelength ranges. A liquid crystal having first and second color display electrodes, which composes the picture element by a microlens array for light fluxes of the first and second wavelength ranges that are incident at different angles, and which corresponds to the respective wavelength ranges. Since the light is condensed on the part, it becomes possible to perform light modulation processing on the light fluxes in the two wavelength regions by one liquid crystal display element.
By using both of the first and second wavelength ranges, the P-polarized light and the S-polarized light of the light source light can be effectively utilized without waste and a color display image in the projection type color liquid crystal display device can be obtained. There is an effect that can be very bright.

According to the projection type color liquid crystal display device according to the present invention (Claims 2 and 3), it is possible to provide the three components required for color image display.
Regarding the light in the first and second wavelength ranges of the two wavelength ranges, the first and second liquid crystal are separately generated for the first linearly polarized light and the second linearly polarized light created from the light source light. Since the light modulation processing is performed by the display element and the transmitted light from the both liquid crystal display elements is combined, the light in the dark wavelength region of the light source light is divided into the P-polarized component and the S-polarized component of the light source light. Both of them can be effectively used without waste, and thus a very bright color image can be formed.

According to the present invention (Claim 4), the first
And the picture elements corresponding to the second wavelength region are arranged in a matrix as a whole so as to be alternately positioned in the vertical direction and the horizontal direction, and the microlens array is provided in two picture elements adjacent in the vertical direction. Since the micro lenses corresponding to are arranged in a zigzag pattern, there is an effect that the oblique line display on the display screen can be made relatively smooth.

According to the present invention (Claim 5), the first
And each of the picture elements corresponding to the second wavelength region are arranged such that a picture element row composed of the first picture element and a picture element row composed of the second picture element are alternately located, and the microlens Since the microlenses of the array are arranged so as to straddle the adjacent first and second picture elements, the line display in the vertical direction or the horizontal direction on the display screen can be made relatively smooth.

According to the present invention (Claim 6), the first
And the respective picture elements corresponding to the second wavelength region are arranged such that the first and second picture element rows consisting of the first and second picture elements are alternately located, Since each microlens is composed of a lenticular lens having a substantially semicircular cross section that straddles the adjacent first and second picture element rows, horizontal or vertical line display in the display image can be made relatively smooth. Further, since the vertically long lenticular lens, which constitutes the microlens and in which the power of the condensed light is linearly distributed in a certain direction, is larger than the quadrangular microlens, it is relatively easy to manufacture, and its manufacturing cost is also high. It has the effect of being cheaper.

According to the present invention (Claim 7), the third
The liquid crystal display element of, has a picture element corresponding to the third wavelength band of the three wavelength bands necessary for color image display, and collects the light flux corresponding to the wavelength band on each picture element by the microlens. Since the light is made to illuminate, even if the aperture ratio of each picture element is small, it is possible to condense all the light incident on the liquid crystal display element onto each picture element. Becomes brighter, and the light utilization efficiency of the entire device can be improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining a configuration of a projection type color liquid crystal display device according to an embodiment of the present invention.
In FIG. 1A, the passage path of the P-polarized light (first S-polarized light) separated from the light source light (non-polarized light) is separated from the light source light (non-polarized light) in FIG. A passage path of S-polarized light (second S-polarized light) is shown.

FIG. 2 is a side view for explaining a positional relationship between a pixel array and a microlens array in the first and second liquid crystal display elements of the above embodiment.

FIG. 3 is a plan view for explaining the positional relationship between the pixel arrays and the microlens array in the first and second liquid crystal display elements of the above embodiment, and FIGS. 3 (a), 3 (b),
FIG. 3C shows an example in which the positional relationship is different.

FIG. 4 is a diagram showing a cross-sectional structure of a liquid crystal display panel in an embodiment of the present invention and a conventional three-plate projection type color liquid crystal display device.

FIG. 5 is a diagram for explaining the positional relationship between a pixel array and a microlens array of a liquid crystal display panel in a conventional three-plate projection type color liquid crystal display device.

FIG. 6 is a diagram showing an example of a configuration of a conventional three-plate projection type color liquid crystal display device.

FIG. 7 is a side view for explaining the positional relationship between the pixel array and the microlens array of the third liquid crystal display element of the above embodiment.

FIG. 8 is a plan view for explaining the positional relationship between the pixel array and the microlens array of the third liquid crystal display element of the above embodiment.

[Description of Reference Signs] 1 light source (lamp) 2R, 2G, 5R, 5B, 10B, 10R dichroic mirrors 3G, 3RB ₁ , 3RB ₂ liquid crystal display element 4 field lens 6 projection lens 7 screen 8, 11 first, second Polarization beam splitters 9a, 9b First and second λ / 2 plates 12, 18 Polarizing plates 13a, 13b Microlens arrays 13a ₁ , 13a ₂ , 13b ₁ Microlenses 14, 14a, 14b Liquid crystal display panels 15R, 15G, 15B pixel 15R _L, 15B _L pixel columns 16 counter substrate 17 active matrix substrate 51 to 55 projection of the reflecting mirror 100 three-plate type color liquid crystal display device Lg optical system of the optical axis

Claims (7)

[Claims] 1. A color filter is provided so as to correspond to first and second wavelength bands of three wavelength bands required for color image display,
Receiving the display signals corresponding to the respective wavelength ranges, the first and second color display electrodes for driving the liquid crystal forming the picture element and the luminous fluxes of the first and second wavelength ranges incident at different angles are provided. And a microlens array that configures the picture element and focuses light on a liquid crystal part corresponding to each wavelength region, and the microlens array includes a plurality of microlenses corresponding to a plurality of adjacent picture elements, A liquid crystal display device configured such that the light fluxes of the first and second wavelength bands incident at the different angles are incident on the liquid crystal parts of the picture elements corresponding to the respective wavelength bands by the respective microlenses. 2. A parallel light beam emitted from a predetermined light source is set to P
A light flux processing means for separating polarized light and S-polarized light, rotating at least one polarization plane of the both polarized lights, and creating first and second linearly polarized light having uniform polarization planes, and a color image. Light modulation processing is performed on the light fluxes of the first and second wavelength bands in the first linearly polarized light, which are provided corresponding to the first and second wavelength bands of the three wavelength bands necessary for display. And a first liquid crystal display element for providing the first and second wavelength ranges of the three wavelength ranges, the first and second wavelength ranges of the second linearly polarized light. A second liquid crystal display element that performs a light modulation process on the light flux, and a second liquid crystal display element that is provided in correspondence with a third wavelength band of the three wavelength bands and is provided in one of the first and second linearly polarized lights. Third
And a third liquid crystal display element for performing light modulation processing on the light flux in the wavelength range of, and An optical system for superimposing and projecting on a display screen to synthesize a color image, wherein the first and second liquid crystal display elements are different from each other in luminous flux having the first and second wavelength ranges. A projection type color liquid crystal display device configured to enter from a direction. 3. The projection type color liquid crystal display device according to claim 2, wherein the first and second liquid crystal display elements have first and second wavelengths of three wavelength bands necessary for color image display. The first and second color display electrodes which are provided so as to correspond to the respective wavelength regions and which receive the display signals corresponding to the respective wavelength regions and drive the liquid crystal forming the picture element, And a microlens array for condensing the light flux of the second wavelength band on the liquid crystal parts corresponding to the respective wavelength bands forming the picture element. The microlens array is provided with a plurality of adjacent picture elements. A plurality of microlenses corresponding to the above, and the light fluxes of the first and second wavelength ranges that are incident at different angles are incident on the liquid crystal parts of the picture elements corresponding to each wavelength range by each microlens Projection Color liquid crystal display device. 4. The projection type color liquid crystal display device according to claim 3, wherein the picture element corresponding to the first wavelength band and the picture element corresponding to the second wavelength band are arranged in a vertical direction and a horizontal direction. Are arranged in a matrix as a whole so that they are alternately located in the vertical direction. Each of the microlenses forming the microlens array corresponds to two adjacent picture elements in the vertical direction or the horizontal direction, and A projection-type color liquid crystal display device arranged such that the center of the optical axis is located at the center portion between them. 5. The projection type color liquid crystal display device according to claim 3, wherein the first picture element corresponding to the first wavelength range and the second picture element corresponding to the second wavelength range are provided. The picture element rows made up of the first picture elements and the picture element rows made up of the second picture element are arranged so as to be alternately positioned, and each microlens forming the microlens array is A projection type color liquid crystal display device which is arranged so as to correspond to adjacent first and second picture elements and whose optical axis center is located at a central portion between the adjacent first and second picture elements. 6. The projection type color liquid crystal display device according to claim 3, wherein the first picture element corresponding to the first wavelength range and the second picture element corresponding to the second wavelength range are provided. A first picture element row composed of the first picture element and a second picture element row composed of the second picture element are arranged so as to be alternately located, and the microlens array is configured. Each of the microlenses corresponding to the adjacent first and second picture element rows has a substantially semicircular cross section in which the optical axis center is located in the central portion between the adjacent first and second picture element rows. Projection type color liquid crystal display device consisting of the lenticular lens. 7. The projection type color liquid crystal display device according to claim 3, wherein the third liquid crystal display element is provided so as to correspond to a third wavelength band of three wavelength bands necessary for color image display. A color display electrode for driving a liquid crystal forming a picture element and receiving a display signal corresponding to the wavelength range, and a luminous flux corresponding to the wavelength range provided for the picture element. A projection type color liquid crystal display device comprising: a microlens array made up of microlenses for condensing light on a liquid crystal part that constitutes an element.