JPH11160696A - Color image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent pure color luminance from decreasing due to generation of discrimination of liquid crystal and to prevent relation of complementary colors from going out of balance, in a color image display device provided with color filters and a liquid crystal panel part. SOLUTION: Each picture element electrode concerning the same color of a picture element electrode layer 13 is aligned in a certain direction, and the orientation of liquid crystal molecules in a liquid crystal layer 16 is arranged so that a map projected onto the picture element electrode layer 13 in the direction of the orientation coincides with the alignment direction of the picture element electrode, and thus, each picture element electrode is made to be resistant to be influenced by a lateral electric field generated between the picture element electrodes in the complementary relation with each other. A phase plate 6 is placed between a color filter 3 and a liquid crystal panel 1, and a plane of polarization of s-polarized light component diffracted through the color filter 3 is two-dimensionally rotated so as to form an angle of 45 degrees with the orientation of the liquid crystal molecules, the polarized light modulated and reflected by the liquid crystal panel part 1 is rotated by 135 degrees to be transformed to p-polarized component, and is thereby transmitted through the color filter 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color image display device, and more particularly to a structure for preventing the occurrence of liquid crystal disclination in a reflection type or transmission type liquid crystal image display device, and a single unit as a spatial light modulator. A color image display device using the micromirror device.

[0002]

2. Description of the Related Art Recently, there has been an increasing demand for a projection type display device for displaying an image on a large screen, such as a display for outdoor public use or a traffic control operation, or a display for displaying a high-definition image such as a high definition image. ing. The projection type display devices are roughly classified into a transmission type and a reflection type.
In both systems, a spatial light modulator using an LCD (Liquid Crystal Display) panel is applied, the readout light is incident on the LCD panel, and the incident light is modulated by the pixel unit corresponding to the video signal and projected. They are getting light. Here, the LCD panel is composed of an active matrix substrate in which switching elements such as thin film transistors and pixel electrodes whose potentials are controlled by the switching elements are formed on a semiconductor substrate, and a common electrode formed on a transparent substrate (such as a glass substrate). And a liquid crystal layer sealed between the active matrix substrate and the common electrode film. The potential difference between the common electrode film and each pixel electrode is changed for each pixel electrode in accordance with a video signal. The readout light is modulated by controlling the orientation of.

[0003] The difference between the transmission system and the reflection system is that the former forms the active matrix substrate transparent and uses the transmitted light of the LCD panel as projection light, while the latter uses the pixel electrode of the active matrix substrate as a reflection electrode or dielectric. It is configured as an electrode for controlling the orientation of liquid crystal via a body mirror film or the like, and the reflected light from the LCD panel is used as projection light.
In general, the reflection type has a large aperture ratio in the liquid crystal cell part because there is no need to provide a black stripe in the liquid crystal layer, and the heat generation due to the absorption of read light is very small. , A brighter image can be obtained while irradiating the readout light with a large value.

Conventionally, in a transmission type projection color image display device, light from a light source is separated into three primary colors (R, G, B) by a dichroic mirror, and three transmission type LCD panels corresponding to each color are used. And combining each transmitted light 3
Although a color image was obtained using a color combining optical system, since the apparatus becomes large and the manufacturing cost increases, each transparent pixel electrode related to each color of the LCD panel is arranged in a stripe arrangement, a mosaic arrangement, or a delta arrangement, An apparatus has been proposed in which a single-plate color filter in which filter elements of each color are arranged in correspondence with the arrangement is provided so that color projection light can be obtained in one system. However, in the device having such a configuration, of the readout light (white light) transmitted through the LCD panel and incident on the color filter, only one of the three primary colors is transmitted through the color filter, and the other two colors are transmitted through the color filter. Since the color component is not used, the light utilization rate becomes extremely low.

Therefore, a color filter using a transmission type hologram has been proposed in relation to a spatial light modulator of a transmission type projection type color image display device (Japanese Patent Laid-Open No. 6-308).
No. 332). First, an example of a spatial light modulator disclosed in JP-A-6-308332 is shown in FIG. 8, in which a color filter 52 composed of a transmission hologram is arranged to face an LCD panel 51, and the color filter 52 The readout light incident by the diffraction / spectral function of the transmission hologram is diffracted / spectralized into R, G, and B components, and condensed on the transparent pixel electrodes 51r, 51g, and 51b corresponding to the corresponding color of the LCD panel 51. Here, the transmission hologram of the color filter 52 is the unit hologram 52
p is formed in an array at the same pitch as the arrangement pitch of the set of the transparent pixel electrodes 51r, 51g, 51b on the LCD panel 51 side,
The unit hologram 52p condenses the R, G, and B wavelength band components on the transparent pixel electrodes 51r, 51g, and 51b with different diffraction angles. Therefore, according to the configuration of the spatial light modulator, a projection type color image display device using incident light without waste can be realized.

Further, the inventor of the present application has filed an earlier application (Japanese Patent Application No.
No. 94453), a color filter composed of a hologram having a wavelength dependency in diffraction efficiency, having a polarization selectivity for mainly diffracting only one polarized light component, and having a function of condensing diffracted polarized light. And a reflection-type projection type color image display device using the color filters. First, FIG. 9 is a sectional view schematically showing a structure of a main part of the color image display device. In the figure, 1 is an LCD panel, 2 is a thin glass layer, 3 is a color filter, 4 is a glass substrate, and 5 is a coupling prism. Here, the LCD panel 1 has a glass substrate or a Si substrate 11, an active matrix drive circuit 12 formed on the substrate 11, and pixel electrodes 13r, which are selectively controlled and driven by the active matrix drive circuit 12.
A pixel electrode layer 13 in which 13g and 13b are regularly arranged, a dielectric mirror film 14, an alignment film 15, a light modulation layer 16 in which liquid crystal is sealed by spacers, an alignment film 17, and a transparent common electrode It has a structure in which the film 18 and the film 18 are sequentially laminated.

Next, among the above components, components other than those already described or obvious will be described. The pixel electrodes 13r, 13g, 13b of the pixel electrode layer 13 are R, G,
B corresponds to each color of B, and these sub-pixels constitute one pixel as a set. In general, a stripe arrangement, a mosaic arrangement, and a delta arrangement are employed as the planar arrangement. You. Here, a stripe arrangement is employed, and the pixel electrodes 13r, 13g, and 13b of the same color are arranged in one direction (the direction perpendicular to the paper surface in FIG. 9) in a plan view.

As the light modulation layer 16, a liquid crystal having an operation mode such as a TN mode, an HFE mode, an FLC mode, and a DS mode can be applied. The alignment films 15 and 17 are provided according to the type of the applied liquid crystal. This is omitted when a scattering-type liquid crystal or the like that takes the DS mode is used. The coupling prism 5 is made of a flat glass plate,
One end face is formed perpendicular to the incident direction of the reading light, the end face becomes the reading light incidence face, and the upper side face becomes the projection light emission face. Although the glass substrate 4 is interposed between the coupling prism 5 and the color filter 3 in FIG. 9, they may be integrally formed, and in any case, the glass substrate 4 is adhered to the surface of the color filter 3. Can be In FIG. 9, the thickness of the glass substrate 4 and the coupling prism 5 is drawn thinner than the thin glass layer 2, but is drawn as such in order to clarify the structure and optical function of the device. In an actual apparatus, the thickness of the glass substrate 4 and the coupling prism 5 is generally larger than the thickness of the thin glass layer 2.

The color filter 3 is an important functional element in this device, and its features will be described in detail in advance. This color filter 3 is a transmission hologram composed of a holographic lens array.
The incident light including the three primary colors is diffracted and separated for each primary color.
It has a function of condensing light substantially vertically to the positions of the corresponding pixel electrodes 13r, 13g, 13b of the CD panel 1. That is, the principal ray of the light beam is made to enter the pixel electrodes 13r, 13g, 13b substantially perpendicularly, and the light beam is made to act on the pixel electrodes 13r, 13g, 13b by the lens action.
Focus on Strictly speaking, since the dielectric mirror film 14 is applied, light is condensed on the film (this is expressed in FIG. 9). Since it is extremely thin compared to the size of the electrodes 13r, 13g, 13b, hereinafter, the description will be made assuming that light is focused on the surfaces of the pixel electrodes 13r, 13g, 13b.

This transmission type hologram has a three-layer structure composed of an R holographic lens array layer 3r, a G holographic lens array layer 3g, and a B holographic lens array layer 3r. Each holographic lens array layer 3r, 3g, 3b has a holographic lens 3re, 3ge, 3be corresponding to a unit hologram arranged in a plane, but each holographic lens 3re, 3g, 3b of each layer 3r, 3g, 3b. 3be
Are positioned so as to pass through substantially the center of each of the corresponding pixel electrodes 13r, 13g, 13b on the LCD panel 1 side, and in this apparatus, as described above, each of the pixel electrodes 13r, 13r
Since g and 13b are striped, the holographic lenses 3re, 3ge, and 3be also have an arrangement corresponding to them. That is, the individual holographic lens array layers 3r, 3g, 3b
, The holographic lenses are arranged at the same pitch as the vertical and horizontal pitches of the pixel electrodes for the corresponding colors, but when viewed in a plan view with three layers stacked, the holographic lenses for each color 3re, 3ge, 3be partially overlap each other, and the positional relationship is such that the holographic lenses 3re, 3ge, 3be of three colors are arranged at a pitch of 1/3 with respect to the pitch of the pixel electrode of one color. Has become.

Incidentally, each holographic lens array layer
The holographic lenses 3re, 3ge, and 3be corresponding to the unit holograms of 3r, 3g, and 3b are formed such that the holograms diffract and disperse the S-polarized component of the wavelength band related to the corresponding color. The characteristics will be described with reference to FIG. The figure shows that, as an example, the wavelength of the incident light is 54
0 nm, the modulation amount Δn of the refractive index with respect to the hologram photosensitive material is 0.03, and the thickness t of the hologram is set so that the diffraction efficiency of the S-polarized component becomes 100% with respect to the angle (bend angle) between the readout light and the diffracted light. The diffraction efficiency of the P-polarized light component was obtained by calculation under the condition of. As is apparent from this figure, when the bend angle is large, a characteristic of diffracting both the S-polarized component and the P-polarized component almost 100% is obtained. When the bend angle is set to 120 ° or less, the diffraction efficiency of the P-polarized component is reduced by 50%. Can be 90
It can be reduced to 0% by approaching °.

Further, the characteristic of the diffraction efficiency greatly depends on the wavelength of the incident light. Conversely, by utilizing the wavelength dependence, the S-polarized light component can be reduced to 100% at a desired wavelength. It is also possible to perform an optimal design such that diffraction is performed at a near diffraction efficiency and the diffraction efficiency of the P-polarized light component becomes extremely small. Therefore, the color filter formed of the transmission type hologram diffracts only the S-polarized light component of each wavelength band with high diffraction efficiency for each of R, G, and B colors, and has a high diffraction efficiency.
It can be configured as a holographic lens array that suppresses the diffraction efficiency of the polarized light component.

FIG. 11 to FIG.
R, G, based on the optimal design conditions when 5 °
The relationship between the diffraction efficiency of each hologram for B and the wavelength of incident light is shown. In each figure, the solid line indicates the S-polarized light component, and the broken line indicates the P-polarized light component. A diffraction efficiency of about 100% is obtained for the S-polarized light component near the center wavelengths of R, G, and B, respectively. Is suppressed to about 18% or less. When a color filter composed of holograms having the characteristics shown in FIGS. 11 to 13 is used for the color filter 3 of FIG. 9, the incident angle θ of the read light with respect to the color filter 3 is 75 ° (= 180−105). ; Bend angle = 105
°), the holographic lenses 3re, 3ge, 3
The be can mainly diffract only the S-polarized component, and emit the S-polarized component vertically to the pixel electrodes 13r, 13g, and 13b of the corresponding color.

In the above color filter 3, R, G, B
Holographic lens arrays 3r, 3g, which have wavelength dependence in diffraction efficiency for each hologram photosensitive material prepared for each spectral color of
3b is recorded for each spectral color, and a configuration in which they are stacked is used, but a holographic lens array 3r, which has a wavelength dependence in diffraction efficiency as described above, for a single-plate hologram photosensitive material. 3g, 3b may be multiplex-recorded,
In that case, there is no need to mechanically align each layer, and a computer generated hologram or the like can be applied.

Here, returning to FIG. 9, the readout light radiated from the light source (not shown) is perpendicularly incident on the incident surface of the coupling prism 5 via the incident optical system (not shown), The light passes through the ring prism 5 and the glass substrate 4 and enters the color filter 3 at an incident angle of 75 °. The reading light incident on the color filter 3 is first split and diffracted by the holographic lens array layer 3r for R color. Each holographic lens 3re of the array layer 3r mainly diffracts only the S-polarized component of the light of the wavelength band related to the R color, and the components of the other wavelength bands included in the read light and The P-polarized light component in the wavelength band for the R color is transmitted as it is. Specifically, each holographic lens 3re has R
While diffracting the S-polarized component with a diffraction efficiency close to 100% in the wavelength band related to the color, the diffraction efficiency of the P-polarized component is set to 2
LCD panel diffracted under the condition that it is suppressed to 0% or less, and the diffracted light is positioned on the optical axis by a lens function.
The light-collecting light flux is set to target the R-side pixel electrode 13r on the first side. Note that the P-polarized light component in the wavelength band for the R color is also slightly diffracted and becomes a convergent light beam like the S-polarized light component.
Therefore, each holographic lens 3re of this array layer 3r
Is to make a light-collecting light flux composed of an S-polarized component related to the R-color wavelength band and a slight P-polarized component in the band perpendicularly incident on the holographic lens array layer 3g for G color, And the P-polarized component in the R color wavelength band that has not been diffracted are transmitted, and are incident on the G color holographic lens array layer 3g in the traveling direction of the readout light.

Next, in the holographic lens array layer 3g for G color, since each holographic lens 3ge mainly diffracts only the S-polarized light component of the light in the wavelength band related to G color, Holographic lens array layer 3r for
While diffracting the S-polarized light component of the wavelength band related to the G color in the light transmitted as it is with a diffraction efficiency close to 100%,
The LCD panel 1 located on the optical axis of the lens 3ge is diffracted under the condition that the diffraction efficiency of the polarized light component is suppressed to 20% or less.
The light-collecting light flux is set to target the pixel electrode 13g of G color on the side. On the other hand, S related to the wavelength band of R color that is incident vertically
A convergent light flux composed of a polarized light component and a slight P-polarized light component in the band is directly incident on the holographic lens array layer 3b for B color, and the holographic lens array layer for R color.
Among the light that has passed through 3r as it is, components that were not subjected to the diffraction action in this layer 3g (components other than the R and G wavelength bands, the P-polarized component in the R wavelength band, did not diffract) The G-color wavelength band (P-polarized light component) is also transmitted as it is and made incident on the B-color holographic lens array layer 3b in the traveling direction of the readout light.

Next, since each holographic lens 3be of the holographic lens array layer 3b mainly diffracts only the S-polarized light component of the light of the wavelength band related to B color, R
Diffraction of the P-polarized light component while diffracting the S-polarized light component of the wavelength band related to the B color out of the light transmitted through the holographic lens array layers 3r and 3g for the color and the G color with a diffraction efficiency close to 100%. Diffraction is performed under the condition that the efficiency is suppressed to 20% or less, and the light is condensed light beam targeting the G pixel electrode 13b on the LCD panel 1 side located on the optical axis of the lens 3be. On the other hand, the convergent luminous fluxes of the R and G colors, which are vertically incident, are directly emitted to the thin glass layer 2 and the two layers 3r out of the light directly transmitted through the holographic lens array layer 3g for G color. , 3g, components excluded from the diffraction effect (components other than the wavelength bands of R, G, and B colors, R
The P-polarized light component in the color band of G and the G-polarized light, and the P-polarized light component in the B-color wavelength band which has not been diffracted are also transmitted as they are and emitted to the thin glass layer 2 in the traveling direction of the reading light.

As a result, from the color filter 3,
It consists of an S-polarized light component in the R color wavelength band and a slight P-polarized light component in each band, and a convergent light flux targeting the pixel electrode 13r, an S-polarized light component in the G color wavelength band and a slight P-polarized light component in each band. A convergent light flux composed of a polarized light component and targeting the pixel electrode 13g, a convergent light flux composed of an S-polarized light component of the B color wavelength band and a slight P-polarized light component of each band, and targeting the pixel electrode 13b, and Zero-order light composed of components other than the wavelength band of each color and the P-polarized component of the wavelength band of each color is emitted.

The above-mentioned condensed light flux is incident on the LCD panel 1 through the thin glass layer 2 and then is applied to the common electrode film 18.
Pixel electrode layer through the alignment film 17, the light modulation layer 16, and the alignment film 15.
The light is focused on the 13 corresponding pixel electrodes 13r, 13g, 13b, and the dielectric mirror film 14 on the surface of each pixel electrode 13r, 13g, 13b.
, And becomes a divergent light flux and re-enters the corresponding holographic lenses 3re, 3ge, and 3be of the color filter 3. However, a control voltage corresponding to a video signal that determines the state of one pixel is individually applied to each pixel electrode 13r, 13g, 13b by the active matrix drive circuit 12, and the common electrode film 18
Since the liquid crystal of the light modulation layer changes the alignment state according to the potential between the pixel electrodes 13r, 13g, and 13b, the above-mentioned S-polarized light component is generated in the process of reciprocating between the color filter 3 and the LCD panel 1. After receiving the modulation corresponding to the control voltage, the light enters the holographic lenses 3re, 3ge, and 3be again. That is, when X% modulation is performed, (100-X)
% Remains the S-polarized component, but X% becomes the P-polarized component and re-enters the holographic lenses 3re, 3ge, and 3be.

FIG. 14 schematically shows the state for the S-polarized light component in the G wavelength band. The S-polarized light component diffracted by the holographic lens 3ge is condensed at the approximate center of the pixel electrode 13g on the optical axis of the lens. The light is converted into a P-polarized light component and enters the holographic lens 3ge. At this time, the modulated light re-enters the holographic lens 3ge via an optical path having a symmetrical relationship with the optical axis to the pixel electrode 13g with respect to the optical axis. In FIG. 14, the angle of incidence and the angle of reflection with respect to the pixel electrode 13g are large, but in practice the angles are extremely small because the holographic lens 3ge is minute.

As described above, the holographic lens 3ge diffracts the S-polarized light component of the incident light with a diffraction efficiency of about 100% and the P-polarized light component with a diffraction efficiency of about 20%, thereby forming a pixel electrode 13g. It was a condensed light beam going to the center. Therefore, about 20% of the P-polarized light component that is re-entered after being modulated is diffracted by the holographic lens 3ge based on the law of light regression and returns to the direction of the incident light (readout light). The component passes through the holographic lens 3ge as it is. On the other hand, the unpolarized S-polarized component corresponding to the modulation degree and the S-polarized component, which is the modulated P-polarized component obtained by diffracting the readout light by the color filter 3, have the diffraction characteristic of the color filter 3 and the light reversal. Most return to the direction of the incident light (readout light) based on the law. The above operation is the same for the R and G colors. As a result, the P-polarized light component of each color obtained by the modulation passes through the color filter 3 as it is, and passes through the coupling prism 5 from the glass substrate 4 and exits from the exit surface as shown in FIG. And the emitted modulated light is projected into the projection optical system.
(Not shown) and projected on the screen. .

The zero-order light travels through the thin glass layer 2 and has an incident angle of 75.degree.
The light enters the panel 1, is reflected by the dielectric mirror film 14 at a reflection angle of 75 °, and re-enters the color filter 3 at an incident angle of −75 °. Each holographic lens array layer 3r constituting the color filter 3 , 3g, 3b holographic lens 3re,
3ge and 3be do not have a diffraction characteristic with respect to the incident angle (−75 °), and the re-entered 0th-order light passes through the color filter 3 and passes through the coupling prism 5 from the glass substrate 4 to read out the light. From the end face opposite to the incident face.

[0023]

As described above, by using a color filter having both the wavelength dependence of the diffraction efficiency by the hologram, the polarization selectivity, and the light collecting function, a small and high light utilization rate can be secured. Although a projection type color image display device is realized, if color separation is efficiently performed for each pixel while arranging pixel electrodes at high density and obtaining high-resolution and high-luminance display characteristics, the pixel electrode layer needs to be formed. A horizontal electric field is generated based on the potential difference between the pixels, which causes disclination in the liquid crystal, which causes a problem of deteriorating the display image quality. In particular, in a stripe arrangement, a mosaic arrangement, or the like, which is adopted as a general arrangement method of the pixel electrodes, the pixel electrodes related to different colors are adjacent to each other, and the lateral electric field reduces the luminance of pure colors and Deterioration of the balance between the complementary colors and the like is noticeable.

Specifically, in the above-described projection type color image display device, the liquid crystal molecules are often vertically aligned in order to increase the change in the contrast ratio with respect to the voltage applied to the pixel electrode. As shown in the example, when the arrangement method of the pixel electrodes 13r, 13g, and 13b is a stripe arrangement, the alignment direction given by the pretilt angle θ is the projection image and the pixel electrode The polarization direction is set so that the arrangement direction forms an angle of 45 °, and the polarization direction of the polarization plane and the projection image of the alignment direction are set so that the highest modulation efficiency of the polarization in the liquid crystal layer is obtained. The light is incident on the liquid crystal layer at an angle of 45 °. When no voltage is applied to the pixel electrode (OFF state), the liquid crystal molecules are in a state of the pretilt angle θ, and when a voltage is applied (ON state).
In this case, a light modulation function of rotating the polarization plane of light by 90 ° at the maximum by optical anisotropy based on the state change is obtained.

However, as shown in FIG. 16A, when the pixel electrode 13g for the G color is in the ON state, the pixel electrode 13 for the R and B colors is turned on.
Assuming that r and 13b are in the OFF state, a horizontal electric field is generated between the pixel electrode 13g and the pixel electrodes 13r and 13b, and as shown in FIG. The liquid crystal molecules do not assume a normal tilt state corresponding to the applied voltage, but rise in the vertical direction on the pixel electrode 13r side, and on the contrary, tend to unnecessarily fall on the pixel electrode 13b side. As a result, when polarized light having a polarization plane in the G stripe direction is incident on the pixel electrode 13g, and light reflected on the electrode surface is detected by the analyzer, the pixel electrode 13r side as shown in FIG. The light intensity is greatly reduced in the area of
The pure color luminance of the G color is reduced, and the balance of the complementary color relationship between the R color and the G color is deteriorated.

Therefore, the present invention has a problem that, in a color image display device, a lateral electric field inevitably generated between adjacent pixel electrodes causes disclination of liquid crystal, thereby deteriorating the quality of a displayed image. It has been created with the aim of eliminating the problem and providing a configuration for obtaining a fine and high-quality projected image. The present invention also provides a novel color image display device by combining the configurations of the color filter and the phase plate used in the invention with a micromirror device.

[0027]

According to a first aspect of the present invention, there is provided a hologram, which diffracts one polarized component of incident light with high efficiency, separates the polarized light into a plurality of polarized lights of different colors, and separates each of the separated colors. A color filter that focuses the polarized light on each pixel electrode of the corresponding color disposed on the reflective pixel electrode layer of the liquid crystal panel described later, and a transparent common electrode layer, a liquid crystal layer and a pixel electrode disposed for each color. In a reflection type color image display device including a liquid crystal panel unit constituted by a reflection type pixel electrode layer which can be individually driven, in the reflection type pixel electrode layer, each pixel electrode related to the same color in a certain direction. Along with the alignment, the alignment direction of the liquid crystal molecules in the liquid crystal layer is set so that the projected image of the direction on the reflective pixel electrode layer substantially matches the alignment direction of the pixel electrodes for each color, and Between the color filter and the liquid crystal panel unit, the polarized light passing through the color filter is rotated so that the polarization plane thereof is at an angle of approximately 45 ° with the alignment direction of the pixel electrodes, and is incident on the liquid crystal panel unit, Further, the polarization plane modulated and reflected by the liquid crystal panel section is changed to a polarization plane of about 135.
The present invention relates to a color image display device provided with a phase plate which is rotated by an angle of ° and made incident on the color filter.

According to the present invention, the projected image of the alignment direction of the liquid crystal molecules on the reflective pixel electrode layer is set in the alignment direction of the pixel electrodes of the same color, and the horizontal direction between the pixel electrodes of different colors. Since the condition is such that the liquid crystal molecules are hardly affected by the voltage, it is possible to suppress a decrease in the luminance of a pure color and a deterioration in the balance of complementary colors due to the disclination of the liquid crystal due to the lateral voltage. On the other hand, the phase plate causes the polarized light to enter the liquid crystal layer so that the direction of the plane of polarization of the polarized light and the projected image of the alignment direction of the liquid crystal onto the reflective pixel electrode layer make an angle of approximately 45 °, and the polarized light in the liquid crystal layer is polarized. Modulation efficiency is set high. Further, the polarization plane of the polarized light modulated by reciprocating in the liquid crystal layer of the liquid crystal panel portion is obtained by rotating the polarization plane of the polarized light at the time of incidence by approximately 90 °, and the phase plate rotates the polarization plane by approximately 135 °. Accordingly, the color filter has a function of allowing polarized light having a polarization plane forming an angle of about 90 ° with respect to the polarization plane of the polarized light diffracted by the color filter to enter the color filter and transmitting the modulated light as it is.

The second invention comprises a hologram, diffracts one polarized component of the incident light with high efficiency, separates the polarized light into a plurality of polarized lights of different colors, and converts the separated polarized lights of the respective colors into a liquid crystal panel to be described later. The color filter that focuses on each pixel electrode of the corresponding color arranged in the transparent pixel electrode layer of the unit, and the transparent common electrode layer and the liquid crystal layer and the pixel electrode arranged for each color can be individually driven In a transmissive color image display device having a liquid crystal panel section composed of a transparent pixel electrode layer and a transparent pixel electrode layer, the pixel electrodes of the same color in the transparent pixel electrode layer are aligned in a certain direction, and the liquid crystal in the liquid crystal layer is The orientation direction of the molecule is set so that the projected image of the direction on the transparent pixel electrode layer substantially matches the alignment direction of the pixel electrode for each color, and the color filter and the liquid crystal A phase plate for rotating the polarized light passing through the color filter so that its polarization plane is at an angle of approximately 45 ° with respect to the alignment direction of the pixel electrodes is provided between the panel portions, and further provided on the emission side of the liquid crystal panel portion. The present invention relates to a color image display device, characterized in that the color filter is provided with an analyzer that transmits only a polarization component opposite to a polarization component diffracted with high efficiency.

In the present invention, the same combination of the color filter and the phase plate as that of the first invention is applied to a transmission type color image display device. A decrease in luminance of pure colors due to discrimination and deterioration of the balance of complementary colors can be suppressed, and only a polarized light component modulated by the liquid crystal panel by the analyzer is extracted as projection light.

The third invention comprises a hologram, diffracts one polarized component of the incident light with high efficiency, separates the polarized light into a plurality of polarized lights of different colors, and converts the separated polarized lights of the respective colors into a reflection type. A color filter that focuses light on a micromirror for a corresponding color provided in the spatial light modulator,
A reflection-type spatial light modulator that controls rotation of each micromirror in accordance with a pixel signal by disposing a rotatable micromirror at a condensing position of polarized light related to each color by the color filter; Interposed between the reflective spatial light modulators, converts linearly polarized light obtained from the color filter to circularly polarized light, and converts circularly polarized light obtained from the reflective spatial light modulator to a polarization plane of the linearly polarized light. The present invention relates to a color image display device provided with a phase plate for converting linearly polarized light having a polarization plane rotated by 90 °.

The present invention realizes a novel color image display device by applying a combination of a color filter and a phase plate to a reflective spatial light modulator using a micromirror. The reflection type spatial light modulator according to the present invention has a large number of micromirrors that can be rotated and controlled in accordance with pixel signals in a plane. The color filter focuses the polarized and diffracted polarized light on the micromirror corresponding to the corresponding color pixel. The polarized light is converted into circularly polarized light by the phase plate and enters the micromirror. The circularly polarized light reflected by the micromirror re-enters the phase plate, and the phase plate converts the circularly polarized light into linearly polarized light having a plane of polarization that forms an angle of 90 ° with the plane of polarization of the linearly polarized light on the outward path. Re-enter the filter. Therefore, the linearly polarized light re-entering the color filter deviates from the diffraction condition of the color filter and passes through the color filter as it is, but the reflection type spatial light modulator changes the rotation angle of each micromirror according to the color pixel signal in the projection direction. When the reflection state is set to the reflection state in a different direction from the reflection state in the projection direction, only the reflection light in the projection direction is obtained as the projection light, and color display according to the pixel signal can be performed.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the color image display device of the present invention will be described in detail with reference to FIGS. << Embodiment 1 >> This embodiment relates to a reflection type color image display apparatus corresponding to the above-mentioned first invention, and FIG. 1 shows a schematic cross-sectional view of a principal part structure of the apparatus. As is apparent from FIG. 9, the basic structure is the same as that shown in FIG. 9, and the LCD panel 1, the thin glass layer 2, the color filter
3, the glass substrate 4 and the coupling prism 5 have a laminated structure. In the present embodiment, it is assumed that each element constituting them is the same. Since the specific contents and functions of each of the layers 1 to 5 and each element have already been described in detail in the section of the prior art, the description thereof is omitted here.

The first feature of the device in this embodiment is that the alignment direction of the liquid crystal constituting the light modulating layer 16 is the same as the alignment of the pixel electrodes in the same color as the direction of the image projected onto the pixel electrode layer 13. The point is that the directions are set to match. That is, the alignment direction of the liquid crystal is set by giving a pretilt angle to the liquid crystal molecules in advance by rubbing the alignment films 14 and 16, but in this embodiment, the tilt direction given by the pretilt angle is determined by the pixel electrode. The direction when projected onto the layer 13 is a direction perpendicular to the plane of the paper in FIG. 1, and R, G,
B corresponds to the alignment direction of each pixel electrode. Also, the second
The feature of 1/1 is between color filter 3 and thin glass layer 2.
The two-wavelength plate 6 is interposed, and the crystal optical axis of the half-wavelength plate 6 is set in a direction at an angle of about 22.5 ° with respect to the alignment direction of the pixel electrodes of the same color. It is in the point. Here, a wavelength film having a birefringence, a mica plate, a quartz plate, or the like is applied to the half-wave plate 6.

Here, as in the case of FIG. 16, in the pixel electrode region of 3 × 3 pixels, the pixel electrode 13g for G color
Is assumed to be in the ON state, and the pixel electrodes 13r and 13b for the R and B colors are in the OFF state.
The orientation state shown in FIG. In the same figure, (A) shows the direction in which the alignment direction of the liquid crystal is projected on the pixel electrode layer 13 together with the arrangement of the pixel electrodes 13r, 13g, 13b (the direction of the white arrow), and (B) and (C) Are pixel electrode 13g and pixel electrode 13, respectively.
This shows the alignment state of the liquid crystal at r and 13b. The liquid crystal molecules above the pixel electrodes 13r and 13b in the OFF state are maintained at a pretilt angle in a state in which the liquid crystal molecules are tilted in the alignment direction by several degrees with respect to the vertical direction. Of liquid crystal molecules are greatly collapsed by an electric field corresponding to the applied color pixel signal.

In this case, the pixel electrodes 13r and 13b and the pixel electrode 13g
16, a horizontal electric field is generated due to the potential difference, and in FIG. 16, discrimination is induced in the liquid crystal by the horizontal electric field.
The liquid crystal molecules on the upper side of g are hardly affected by the horizontal electric field, and the liquid crystal molecules correspond to the cross section taken along the line V-V in FIG. In the entire area of 13 g, the pixel electrode 13 g for G color is largely inclined only in the alignment direction, and no discrimination occurs in the liquid crystal. That is, by setting the orientation direction of the liquid crystal as described above, the orientation direction is perpendicular to the direction of the lateral electric field, and the influence of the lateral electric field generated between the pixel electrodes of different colors in which the liquid crystal molecules are different is the most. Conditions that are difficult to receive are ensured, and the occurrence of disclination can be effectively suppressed. Therefore, as in the case of FIG.
When the light reflected by the electrode surface is detected by the analyzer, the light intensity becomes as shown in FIG. 2E, and it is possible to prevent a decrease in the luminance of the pure color and a deterioration in the balance between the complementary colors. Since the liquid crystal molecules are sensitive to the horizontal electric field in the orientation direction, when the adjacent pixel electrodes of the same color are in the ON state and the OFF state, the horizontal electric field between the adjacent pixel electrodes is in the ON state and the OFF state. Discrimination occurs due to this, but since it occurs between the same colors, it does not affect the balance between the luminance of the pure color and the complementary color relationship.

Next, the change in the state of polarized light from the time of incidence to the time of emission in the device of this embodiment will be described with reference to FIG. However, in the figure, the thick solid line arrow direction indicates the direction of the polarization plane of the polarized light, the thick dotted line indicates the direction of the crystal optical axis of the half-wave plate 6, and the white arrow direction indicates the liquid crystal alignment direction. Shows the direction when projected. First, the color filter 3 condenses the S-polarized light component obtained by diffracting and dispersing the readout light on the pixel electrode for the corresponding color, and the polarized light component passes through the converging path between the half-wave plate 6 and the light modulation layer 16. Pass through the liquid crystal.
In the case of this device, as shown in FIG. 3A, the S-polarized light component of the diffracted light by the color filter 3 has its polarization plane in the alignment direction of the pixel electrodes related to the same color. And that S
Although the polarized light component passes through the half-wave plate 6, the polarization plane at the time of incidence is approximately 22.2 with respect to the direction of the crystal optical axis 6a of the half-wave plate 6.
Since it has an angle of 5 ° (B), the polarized light component after passing through is rotated by approximately 45 ° in its polarization plane (C), and the liquid crystal of the light modulation layer 16 has the polarization plane of the same color. Light is incident as polarized light having an angle of approximately 45 ° with the alignment direction of the pixel electrodes (D).
Therefore, the plane of polarization of the polarized component incident on the pixel electrode layer 13 is approximately 45 degrees with the direction when the orientation direction of the liquid crystal is projected on the pixel electrode.
The light is incident on the liquid crystal of the light modulation layer 16 in an angle relationship at which the most efficient modulation efficiency is obtained.

The polarized light incident on the light modulating layer 16 is
(Reflection at the pixel electrode) → receives modulation according to the voltage applied to the pixel electrode in the process of passing through the path of the liquid crystal layer (D, E),
It re-enters the half-wave plate 6 (F). Then, as the light is reciprocated in the liquid crystal layer and undergoes modulation, the plane of polarization of the polarized light is rotated by 90 ° and enters the half-wave plate 6 (E, F), but the crystal optical axis 6a of the half-wave plate 6 Has an angle of about 67.5 ° with respect to its polarization plane (F), the polarized light component after passing through the half-wave plate 6 is rotated by about 135 ° and enters the color filter 3 (G, F).

Accordingly, the polarization component incident on the color filter 3 is a P-polarization component whose polarization plane is perpendicular to the polarization plane of the S-polarization component obtained by diffracting and separating the readout light.
(G) Since the color filter 3 has a polarization selectivity for efficiently diffracting only the S-polarized component, the modulated P-polarized component passes through the color filter 3 as it is. As a result, the P-polarized light component transmitted through the color filter 3 can be used as the modulated projection light, while the polarized light component that re-enters the color filter 3 without modulation according to the degree of modulation remains the S-polarized light component. Therefore, the light returns to the incident direction of the read light based on the diffraction characteristic of the color filter 3. That is, 1 /
The two-wavelength plate 6 is the most efficient in the liquid crystal layer by rotating the polarization plane of the S-polarized light component diffracted by the color filter 3 in a configuration in which the alignment direction of the liquid crystal is set as described above to prevent disclination. And the polarization component modulated by the liquid crystal layer is transmitted as a P polarization component through the color filter 3.

<Embodiment 2> This embodiment is a modification of the above-described embodiment 1, and the basic laminated structure of the apparatus is shown in FIG.
FIG. 4 shows a schematic principle diagram similar to that of FIG. The features of this embodiment are as follows: (1) FIG.
As shown in (A), in the color filter 3 having a rectangular planar shape as a whole, the holographic lens array layers 3r, 3g, 3b for the respective colors (R, G, B) are formed by the vertical and horizontal sides of the rectangular shape. (2) In correspondence with the configuration of the color filter 3, as shown in FIG. In the pixel electrode layer 13 to be formed, the pixel electrodes of the same color are aligned at an inclination angle of about 45 ° with respect to the vertical side and the horizontal side, (3) the alignment direction of the liquid crystal constituting the light modulation layer 16 Is set so that the direction of the image projected onto the pixel electrode layer 13 and the alignment direction of the pixel electrodes in (2) above, and (4) the reflection type color image display of FIG. A half-wave plate is applied in the same manner as the half-wave plate 6 used in the apparatus, and FIGS. 4 (B), (C), (E), (F) ), The crystal optical axis 6a 'of the half-wave plate is set to form an angle of about 22.5 ° with respect to the alignment direction of the pixel electrodes of the same color. According to the pixel arrangement based on the color filter 3 of (1) and the pixel electrode layer 13 of (2), color display by a pseudo mosaic arrangement method becomes possible.

In this embodiment, the reading light is applied to the holographic lens array layers 3r, 3r in the color filter 3.
g, 3b are incident from a direction perpendicular to the juxtaposition direction, and each holographic lens array layer
The holographic lenses 3re, 3ge, and 3be of 3r, 3g, and 3b diffract and disperse the readout light and focus the S-polarized light component of each color to the pixel electrodes 13r, 13g, and 13b corresponding to the corresponding color of the pixel electrode layer 13.

In this case, the S-polarized light component diffracted by the color filter 3 is incident on the half-wave plate, but the plane of polarization of the S-polarized light component is approximately 22 ° with respect to the crystal optical axis 6a ′ of the half-wave plate. .5
(B), the light passes through a half-wave plate, and its polarization plane is turned into a polarized light rotated by approximately 45 ° and enters the liquid crystal of the light modulation layer 16 (C). Therefore, similarly to the case of the first embodiment, the polarized light incident on the liquid crystal is most efficiently modulated in the liquid crystal layer,
In addition, since the orientation direction of the liquid crystal is set under the condition (3), even when a horizontal electric field is generated between the pixel electrodes of different colors, it is possible to suppress the occurrence of the disclination of the liquid crystal and to reduce the luminance of the pure color. And the deterioration of the balance of the complementary colors can be prevented.

On the other hand, the polarized light modulated on the path of the liquid crystal layer → (reflection at the pixel electrode) → the liquid crystal layer re-enters the half-wave plate by rotating the plane of polarization by approximately 90 ° (D, E). The polarization plane at this stage is approximately 67.5 ° with respect to the crystal optical axis 6a 'of the half-wave plate.
(E), the polarization plane is rotated by 135 ° by passing through the half-wave plate, and the light is again incident on the color filter 3 (F). As a result, similarly to the case of the first embodiment, the modulated polarized light re-entering the color filter 3 is a P-polarized component, and is transmitted as it is without being diffracted by the color filter 3 and used as projection light. Can be In addition, color filters remain unmodulated
The S-polarized light component re-entering 3 is diffracted by the color filter 3 and returns to the incident direction of the read light. As described above, the projection light according to the present embodiment has a color display mode based on a pseudo mosaic arrangement method.

<< Embodiment 3 >> In this embodiment, a combination of the color filter 3 and the half-wave plate 6 of Embodiment 1 is applied to a transmission type color image display device. Corresponding. A schematic configuration of the device according to this embodiment is shown in FIG. 5, and includes a color filter 3 and a half-wave plate.
6, an LCD panel 1 'and an analyzer 7. Here, the combination of the color filter 3 and the half-wave plate 6 is the same as in the first embodiment as described above. LCD panel 1 '
Except that the dielectric mirror film 14 is not interposed and that each pixel electrode of the pixel electrode layer 13 ', the active matrix drive circuit 12', and the Si substrate 11 'are made of a transparent material. 5 has the same laminated structure as the LCD panel 1 of the first embodiment, and the direction in which the liquid crystal orientation of the light modulating layer 16 is projected onto the pixel electrode layer 13 'is perpendicular to the plane of FIG. And R,
The point that the alignment direction of each of the G and B pixel electrodes coincides with that of the first embodiment. Analyzer 7 is an LCD panel
It has a function of transmitting only the P-polarized light component of the modulated light transmitted through 1 '.

In the device of this embodiment, the S-polarized light component of each color diffracted and split by the color filter 3 is focused on the pixel electrode corresponding to the corresponding color of the pixel electrode layer 13 ′.
In the light condensing process, the polarization plane is rotated by 45 ° by passing through the half-wave plate 6, and the polarized light modulated by the liquid crystal of the light modulation layer 16 is further polarized by 90 °. Then, the light is emitted from the LCD panel 1 'to the analyzer 7 side. The rotation state of the polarization plane in the half-wave plate 6 and the light modulation layer 16 is basically the same as that described in the first embodiment with reference to FIGS. 3A to 3E. The only difference is that the polarized light is modulated by the liquid crystal layer in the modulation process from (E) to (E) and then transmitted through the pixel electrode and emitted as it is. Therefore, the plane of polarization of the polarized light that has passed through the half-wave plate 6 is set to the direction that most efficiently undergoes modulation in the liquid crystal layer, and is caused by a lateral electric field generated between pixel electrodes of different colors. Thus, occurrence of disclination in the liquid crystal can be suppressed.

In the first embodiment, the modulated P-polarized light component and the unmodulated S-polarized light component re-enter the color filter 3, and the non-modulated polarized light returns to the readout light side due to its diffraction characteristics. Although only the P-polarized light component, which is the modulated light, could be transmitted, in this embodiment, since the LCD panel 1 ′ is of a transmission type, it is modulated according to the degree of modulation in the liquid crystal layer. The polarized light component and the unmodulated polarized light component are directly emitted from the LCD panel 1 ′. Therefore, in this embodiment, the analyzer 7 is provided on the emission side of the LCD panel 1 ', and only the polarized light component, which is the modulated light, is transmitted and used as the projected light.

Embodiment 4 This embodiment relates to a color image display device in which a combination of a color filter and a quarter-wave plate is applied to a micromirror device, and corresponds to the above-described third invention. FIG. 6 shows a schematic structure of the device according to this embodiment, which is constituted by a combination of the color filter 3 and the quarter-wave plate 21 used in the first embodiment and the micromirror device 22.

Here, the quarter-wave plate 21 is approximately 45 degrees with respect to the polarization plane of the S-polarized component diffracted and split by the color filter 3.
It is interposed so as to have a crystal optical axis in a direction forming an angle of °. On the other hand, the micromirror device 22 constitutes a mirror surface on which a large number of micromirrors 23 rotatably supported by a fine mechanism are arranged on a semiconductor substrate, and is provided directly below the micromirrors 23 so as to correspond to each micromirror 23. The turning angle of the micromirror 23 is individually controlled by an electrostatic field generating circuit (not shown) using a memory element. In the present embodiment, the micromirrors 23 for the respective color pixels are arranged in a stripe shape corresponding to the arrangement of the holographic lenses 3re, 3ge, 3be of the color filter 3, and the driver
24 selectively turns on each electrostatic field generation circuit according to the pixel signal
By switching to the / OFF state, each micro mirror 23
Is changed to two states. More specifically, as shown in FIG. 7, the micromirror 23 is set to a state in which the micromirror 23 reflects the readout light in the vertical direction (projection direction) when the electrostatic field generating circuit is in the ON state (A). Since the light is set in a state of reflecting light in a direction greatly inclined with respect to the projection direction (B), by controlling the rotation angle of each micromirror 23 to any state individually, the incident light is projected light. Or non-projection light can be selected.

In FIG. 6, the color filter 3 condenses the S-polarized light component obtained by diffracting and dispersing the readout light on the micromirror 23 corresponding to the corresponding color.
The light passes through the wave plate 21. In this case, since the crystal optical axis of the quarter-wave plate 21 has an angle of 45 ° with respect to the polarization plane of the S-polarized light component, the light transmitted through the quarter-wave plate 21 becomes circularly polarized light. The light is focused on the micro mirror 23. The circularly polarized light condensed on each mirror surface is reflected in the projection direction or the non-projection direction depending on the control state of each micromirror 23 according to the pixel signal, and re-enters the quarter-wave plate 21. The four-wavelength plate 21 converts the incident circularly polarized light into a P-polarized light component and
Output to 3. Therefore, all the light reflected by each micromirror 23 becomes a P-polarized light component and is transmitted as it is without being diffracted by the color filter 3, and is divided into a projection direction and a non-projection direction according to the control state of each micromirror 23. Is emitted.

In this embodiment, the light reflected by the micromirror 23 in the ON state is used as the projection light. For example, in the state shown in FIG. 6, only the P-polarized light components of the R and G colors are used. As the projection light, the P-polarized light component of the B color becomes the non-projection light, and as a result, the projection light expressing the yellow region is obtained. Naturally, full-color display becomes possible by changing the display.

In a conventional color image display device using a micromirror device, a projection image of each color is synthesized using three micromirror devices (corresponding to R, G, and B) to realize a full-color projection image. Method, using a single micromirror device with high-density pixels, rotating the color wheel, or switching the color of the illuminating beam in a period that is sufficiently short with respect to the video field period by a multi-color shutter method using an LCD. R, G,
Although the method of sequentially refreshing B has been adopted, according to the apparatus of this embodiment, only the loading structure of the color filter 3, the quarter-wave plate 21, and the single micromirror device chip, which are extremely simple structures, is used. To obtain a full-color projection image.

[0052]

According to the color image display device of the present invention having the above-described structure, the following effects can be obtained. The invention according to claims 1 and 2 is directed to a reflection type color image display device including a color filter and a liquid crystal panel unit having a function of selectively diffracting polarized light, a function of separating light, and a function of condensing light on a pixel modulation element. In the liquid crystal panel portion, it is possible to prevent the occurrence of liquid crystal discrimination caused by a horizontal electric field between pixel electrodes related to different color pixels, thereby preventing a decrease in pure color luminance and a deterioration in the balance of complementary colors, thereby providing high quality color. Enable image display. According to the third and fourth aspects of the present invention, the same effect can be achieved in a transmission type color image display device including the color filter and a transparent liquid crystal panel. The invention according to claims 5 and 6 is characterized in that the color filter, a reflective spatial light modulator in which a plurality of individually mirror-controllable micromirrors are arranged as color pixel elements, a phase plate, an analyzer, Thus, a reflection type color image display device having an extremely simple configuration and easy control can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a reflective color image display device according to a first embodiment of the color image display device of the present invention.

FIG. 2 shows an arrangement of pixel electrodes in an arrangement of pixel electrodes based on a stripe arrangement method, in which pixel electrodes for R and B colors are in an OFF state and pixel electrodes for G color are in an ON state. (A) showing the direction in which the orientation direction of the liquid crystal is projected onto the pixel electrode layer, (B) showing the orientation state of the liquid crystal when the pixel electrode is in the ON state, and the orientation of the liquid crystal when the pixel electrode is in the OFF state. (C) showing the state, (D) showing the alignment state of the liquid crystal taken along the line VV in (A), and the light intensity distribution detected in the pixel electrode region for G color. Figure (E)
It is.

FIG. 3 is a diagram showing a state change of polarized light from the time of incidence to the time of emission. However, (A) is the state after passing through the color filter, (B) and (C) are the states before and after passing through the half-wave plate on the outward path, (D) is the state of incidence on the LCD panel, (E) ) Is LCD
(F) and (G) show the state before and after passing through the half-wave plate on the return path, and (H) shows the state of re-entering the color filter and transmitting.

FIG. 4 is a schematic principle view related to a characteristic portion of a reflective color image display device according to a second embodiment. However, (A) shows the parallel arrangement of the holographic lens array layers in the color filter, and (B) and (C) show the relationship between the polarization plane of the polarized light on the outward path and the crystal optical axis of the half-wave plate. , (D) shows the arrangement of the pixel electrode layers of each color in the pixel electrode layer,
(E) and (F) show the relationship between the polarization plane of the polarized light on the return path and the crystal optical axis of the half-wave plate.

FIG. 5 is a schematic configuration diagram of a transmission type color image display device according to a third embodiment.

FIG. 6 is a schematic configuration diagram of a reflective color image display device according to a fourth embodiment.

FIG. 7 is a schematic diagram showing the operation principle of the micromirror device. However, (A) shows the case where the micro mirror is in the ON state, and (B) shows the case where the micro mirror is in the OFF state.

FIG. 8 is a schematic configuration diagram of a transmission type color image display device using a color filter (JP-A-6-308332).

FIG. 9 is a schematic configuration diagram of a reflection type color image display device disclosed in Japanese Patent Application No. 8-294453 by the present inventor.

FIG. 10 shows the wavelength of the incident light λ = 54 for the hologram.
0 nm, the refractive index modulation amount Δn = 0.03, the thickness t is changed, and the diffraction efficiency ηs of the P deflection component when the bend angle is changed while maintaining the diffraction efficiency ηs of the S deflection component at 100%. It is a graph which shows a change.

FIG. 11 is a graph showing diffraction efficiency characteristics of a P-polarized light component and an S-polarized light component in a wavelength band of 400 nm to 700 nm of an incident light with respect to an R color hologram created under an optimum design condition with a bend angle of 75 °.

FIG. 12 is a graph showing diffraction efficiency characteristics of a P-polarized light component and an S-polarized light component in a wavelength band of 400 nm to 700 nm of incident light, for a hologram for G color prepared under an optimum design condition with a bend angle of 75 °.

FIG. 13 is a graph showing diffraction efficiency characteristics of a P-polarized light component and an S-polarized light component in a wavelength band of 400 nm to 700 nm of incident light, for a hologram for B color prepared under an optimum design condition with a bend angle of 75 °.

14 relates to the color image display device of FIG. 9 and reads out the holographic lens for G color in a state where the center of the holographic lens for G color and the center of the pixel electrode of the corresponding color coincide in a plan view. The S-modulation component is focused on the pixel electrode of the corresponding color by diffracting and dispersing the light, reflected and modulated on the pixel electrode side, re-enters the holographic lens, and the P-polarized component after modulation passes through the holographic lens. It is a schematic diagram which shows the process which becomes projection light.

FIG. 15 is a diagram showing the relationship between the arrangement of pixel electrodes and the orientation direction of liquid crystal molecules in a conventional technique.

16 shows that the pixel electrodes for R and B colors are OFF and the pixel electrode for G color is ON in the relationship between the arrangement mode of the pixel electrodes and the orientation direction of the liquid crystal molecules shown in FIG. (A) showing the display state of each pixel when discrimination occurs in the liquid crystal, and FIG.
(B) showing a state of alignment of the liquid crystal in a cross section taken along the -V arrow,
FIG. 7C is a diagram illustrating a light intensity distribution detected in a pixel electrode region for G color.

[Explanation of symbols]

1,1 ', 51 ... LCD panel, 2 ... Thin glass layer, 3,52 ... Color filter, 3r, 3g, 3b ... Holographic lens array for each color (R, G, B), 3re, 3ge, 3be ... Each color (R, G, B) holographic lens, 4 ... glass substrate, 5 ... coupling prism, 6 ... 1/2 wavelength plate, 6a, 6a '... crystal optical axis, 7 ... analyzer, 11, 11' ... Glass substrate or Si substrate, 12, 12 '... active matrix drive circuit, 13 ... pixel electrode layer, 13r, 13g,
13b: pixel electrode for each color (R, G, B), 14: dielectric mirror film, 15, 17: alignment film, 16: light modulation layer (liquid crystal layer), 18: common electrode film, 21: 1/4 Wave plate, 22: micromirror device, 23: micromirror, 24: driver, 51r, 51g, 51
b: Transparent pixel electrode, 52p: Condensing unit hologram.

Claims (6)

[Claims] 1. A hologram, which diffracts one polarized light component of incident light with high efficiency, separates the polarized light into a plurality of polarized lights of different colors, and reflects the separated polarized lights of a reflection type of a liquid crystal panel unit. A color filter that condenses light on each pixel electrode of the corresponding color arranged on the pixel electrode layer, and a reflective type that can individually drive the transparent common electrode layer, the liquid crystal layer, and the pixel electrodes arranged for each color In a reflection type color image display device including a liquid crystal panel section composed of a pixel electrode layer, pixel electrodes of the same color in the reflection type pixel electrode layer are aligned in a certain direction, and liquid crystal molecules in the liquid crystal layer are arranged. Are set such that the projected image of the direction on the reflective pixel electrode layer substantially matches the alignment direction of the pixel electrodes for each color, and the color filter and the liquid crystal panel Between the sections, the polarized light passing through the color filter is rotated so that the plane of polarization thereof is at an angle of approximately 45 ° with respect to the alignment direction of the pixel electrodes to be incident on the liquid crystal panel section, and modulated by the liquid crystal panel section. A color image display device comprising a phase plate for rotating the reflected polarized light by approximately 135 ° to enter the color filter; 2. A polarization plane of polarized light of each color separated by the color filter is in the same direction as an alignment direction of each pixel electrode related to the same color in the reflection type pixel electrode layer, and the phase plate is approximately 22 with respect to the alignment direction. 2. The color image display device according to claim 1, wherein the color image display device is a half-wave plate having a crystal optical axis forming an angle of 0.5 [deg.]. 3. A hologram, which diffracts one polarized light component of incident light with high efficiency, separates the polarized light into a plurality of polarized lights of different colors, and converts the separated polarized lights of the respective colors into a transparent pixel of a liquid crystal panel unit. A color filter that focuses light on each pixel electrode of the corresponding color provided on the electrode layer, and a transparent pixel electrode that can individually drive the transparent common electrode layer, the liquid crystal layer, and the pixel electrodes provided for each color In a transmission type color image display device having a liquid crystal panel unit composed of
Along with aligning the pixel electrodes of the same color in the transparent pixel electrode layer in a certain direction, the alignment direction of the liquid crystal molecules in the liquid crystal layer, and the projection of the pixel electrode of the color in the direction on the transparent pixel electrode layer in each direction is changed. It is set so as to substantially match the alignment direction, and between the color filter and the liquid crystal panel portion, the polarized light having passed through the color filter has its polarization plane at an angle of approximately 45 ° with the alignment direction of the pixel electrodes. A phase plate for rotating the liquid crystal panel portion, and an analyzer for transmitting only a polarization component opposite to a polarization component diffracted by the color filter with high efficiency on the emission side of the liquid crystal panel portion. Color image display device. 4. The polarization plane of polarized light of each color separated by the color filter is in the same direction as the alignment direction of each pixel electrode related to the same color in the transparent pixel electrode layer, and the phase plate is approximately 22. 4. The color image display device according to claim 3, wherein the color image display device is a half-wave plate having a crystal optical axis in a direction forming an angle of 5 [deg.]. 5. A reflection type spatial light modulator, comprising a hologram, diffracting one polarization component of the incident light with high efficiency, dispersing the polarized light into a plurality of polarized lights of different colors, and dispersing the separated polarized lights of the respective colors. A color filter for condensing light on a micromirror for a corresponding color provided in the color filter, and a micromirror rotatable at a condensing position of polarized light for each color by the color filter are disposed, and each micromirror is provided with a pixel signal. A reflective spatial light modulator for controlling rotation in response to the light, interposed between the color filter and the reflective spatial light modulator, and converts linearly polarized light obtained from the color filter into circularly polarized light; A color image display device comprising a phase plate for converting circularly polarized light obtained from the spatial light modulator into linearly polarized light having a plane of polarization rotated by 90 ° with respect to the plane of polarization of the linearly polarized light. 6. The color image display device according to claim 5, wherein the phase plate is a quarter-wave plate having a crystal optical axis in a direction making an angle of approximately 45 ° with respect to the polarization plane of the polarized light obtained from the color filter. .