JP2003233070A - Flat panel type color image display device and information terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat panel type display which is low in electric power and high in luminance and can make display with high color purity. <P>SOLUTION: Blue two-dimensional illuminating light LB obtained through a light guide plate 210 from the array of blue LEDs 201 is applied as back light to an LCD body 100. The pattern of a G fluorescent layer FG emitting fluorescence of G color is formed in a G (green) pixel region AG and the illuminating light LB is converted to display light PG of G color. The pattern of an R fluorescent layer FR emitting fluorescence of R color is formed in a R (red) pixel region AR and the illuminating light LB is converted to display light PR of R color. The illuminating light LB is used as it is as the B color display light in the B (blue) pixel region AB. The B pixel region AB is provided with the B fluorescent layer FB in using ultraviolet rays. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel type color image display device and an information terminal using the same, and more particularly to a technique for improving display brightness and color purity with low power consumption.

[0002]

BACKGROUND OF THE INVENTION As a man-machine interface in a mobile phone, a color liquid crystal display device (color L
CD) has become popular. In addition, the spread of high-speed communication has made it possible to display not only still images but also moving images on mobile phones, and clear image display on mobile phones is required.

On the other hand, in a mobile information device such as a mobile phone, electric power is supplied from a battery, and therefore it is required to suppress the power consumption of the display as much as possible.

These two requirements are in a trade-off relationship, and when the brightness of the backlight of the color LCD is increased while displaying an image at high brightness, the battery consumption becomes large.

In order to deal with such a situation, the blue L
There is an attempt to use an ED (light emitting diode) as a light source and pseudo white light obtained by passing blue light through a fluorescent layer that emits yellow fluorescence as a backlight of a color LCD (for example, a special light source). Kaihei 10-269
No. 822). In this technology, part of the blue light emitted from the blue LED is converted into yellow fluorescence, but the fact that the mixed light of this yellow light and the rest of the blue light is visually equivalent to white is used. To do. As shown in FIG. 15, the white light thus obtained is passed through an array of R (red) G (green) B (blue) color filter layers to obtain RGB pattern light. A variable image display is performed by controlling the transmission intensity of the liquid crystal layer for each pixel.

[0006]

However, even in such a background art, the produced white light becomes color light by passing through the color filter. Therefore, LE
Blue light from the D light source passes through not only the liquid crystal layer and the transparent electrode layer but also two layers of a yellow fluorescent layer and a color filter layer, and light loss in these layers cannot be avoided. In particular, unless the amount of color elements (dye or pigment) in the color filter is increased, the required RGB colors cannot be obtained sufficiently, so that the light loss in the color filter is large.

As a result, the background art has a problem that the display brightness of the image is still low and a clear color image cannot be displayed. Although the display brightness is improved by increasing the number of blue LCDs, the power consumption is increased accordingly.

Further, in the above background art, the light which is visually recognized as white by the mixture of the blue light and the yellow light is used, and the original white light having the spectral distribution spread over each wavelength region is used. is not. In particular, as can be seen from FIG. 13, since the mixed light of blue and yellow has few components in the red wavelength range, a clear red color cannot be obtained even through the red filter.

Under these circumstances, a problem common to flat panel type color displays equipped with a light source is shown. Even when a commercial power source is used, low power consumption and high brightness image display are required from the viewpoint of energy saving. It is desirable to do.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in response to the above circumstances, and in a flat panel type color display, it is possible to obtain a display of high brightness and high color purity while suppressing an increase in power consumption. Is the first purpose.

A second object of the present invention is to obtain an information terminal using a flat panel type color display having such advantages.

[0012]

In order to achieve the above-mentioned object, the invention of claim 1 is a flat panel type color image display apparatus, which is an illuminating section for generating blue illuminating light spread two-dimensionally. And an R pixel region in which an R fluorescent layer that converts the illumination light into R (red) light is formed, and a G pixel region in which a G fluorescent layer that converts the illumination light into G (green) light is formed. An RGB light generation layer that has a two-dimensional repetitive array of B pixel areas that transmit the illumination light as B (blue) light, and obtains RGB image light by applying the illumination light to the repetitive array; And a control structure that is coupled to the RGB light generation layer and controls the output amount of each pixel of the RGB image light in response to an image signal.

According to a second aspect of the present invention, in the color image display device according to the first aspect, at least one of the R fluorescent layer and the G fluorescent layer contains a light diffusing material.

According to a third aspect of the present invention, in the color image display device according to the first or second aspect, the RGB
The light generation layer further includes at least one of an R color filter layer arranged on the R phosphor layer and a G color filter layer arranged on the G phosphor layer.

According to a fourth aspect of the present invention, in the color image display device according to any one of the first to third aspects, the RGB light generation layer further includes a light diffusion layer formed in the B pixel region. .

According to a fifth aspect of the present invention, in the color image display device according to any one of the first to fourth aspects, the RGB light generating layer further includes a B color filter layer formed in the B pixel region. Prepare

According to a sixth aspect of the present invention, in the color image display device according to any one of the first to fifth aspects, the control structure is a liquid crystal provided between first and second transparent electrode layers facing each other. A liquid crystal control structure having a layer and first and second polarizing layers respectively provided on the upper and lower sides of the liquid crystal layer, and controlling the output amount of each of the RGB image lights for each pixel in response to the image signal. It is characterized by becoming.

According to a seventh aspect of the present invention, there is provided a flat panel type color image display device, wherein an illuminating section for generating ultraviolet light that has spread two-dimensionally as illumination light and the illumination light is converted into R (red) light. R pixel area in which the R fluorescent layer is formed, a G pixel area in which the G fluorescent layer that converts the illumination light into G (green) light is formed, and B that converts the illumination light into B (blue) light An RGB light generating layer having a two-dimensional repeating arrangement with a B pixel area in which a fluorescent layer is formed, and obtaining RGB image light by applying the illumination light to the repeating arrangement, and is coupled to the RGB light generating layer. A control structure for controlling the output amount of each of the RGB image lights for each pixel in response to an image signal.

The invention of claim 8 is characterized in that, instead of the illumination light of the invention of claim 7, illumination light spread two-dimensionally including wavelengths from the ultraviolet region to the visible light region is used. .

The inventions of claims 9 and 10 are an information terminal or a mobile phone using the flat panel type color image display device according to any one of claims 1 to 8 as a display portion.

[0021]

<Principle of the Invention><First Principle of the Invention> FIG. 1 is a diagram showing the first principle of the present invention. In a full-color display, generally, pixels of three primary colors of R (red), G (green), and B (blue) (R pixel, G pixel, B pixel) are repeatedly arranged. Further, in the present invention, the blue illumination light LB is used, and the illumination light L is emitted to the R fluorescent layer FR which emits R color fluorescence.
The R pixel is realized by irradiating B, while the G pixel is realized by irradiating the G fluorescent layer FG emitting G color fluorescence with the illumination light LB.

That is, the wavelength distribution of the fluorescence emitted by the G color fluorescent material is in the range of 480 to 640 nm, and the wavelength distribution of the fluorescence emitted by the R color fluorescent material is in the range of 590 to 750 nm. Therefore, as conceptually shown in FIG. 2, the blue illumination light LB located on the shorter wavelength side (higher energy side) than these wavelength regions.
When the G fluorescent layer FG is irradiated with G, as shown in FIG.
The G fluorescent material in the fluorescent layer FG absorbs the photons having the wavelength of the illumination light LB and excites them to the energy level S0. After the state transitions to the energy level S1 lower than this level S0, the photons of the G color light PG are detected. Release to return to initial energy level. In addition, as shown in FIG. 1D, the R fluorescent material in the R fluorescent layer FR also absorbs photons having the wavelength of the blue illumination light LB to be in an excited state, and after transitioning to an energy level lower than this excited state. , R photons of PR light are emitted to return to the initial energy level. Therefore, the region provided with the G fluorescent layer FG can be used as a G color pixel, and the region provided with the R fluorescent layer FR can be used as an R color pixel. The B color pixel can be obtained by directly using the illumination light LB (without undergoing wavelength conversion by the fluorescent material).

The display devices according to the first and second embodiments of the present invention, which will be described later, are constructed on the basis of such a principle of wavelength conversion of blue light.

<Second Principle of the Invention> Further, since the wavelength range of the B-color fluorescence emitted by the B-color fluorescent material is in the range of 420 to 530 nm, RGB fluorescent layers are provided and as shown in FIG. If the ultraviolet light (50 to 400 nm) existing on the shorter wavelength side (higher energy side) than each wavelength region of RGB is used as the illumination light LU, the R fluorescent layer FR is irradiated with this illumination light LU. Not only realizes the G pixel by irradiating the R pixel and the G fluorescent layer FG with the illumination light LU, but also realizes the B pixel by irradiating the B fluorescent layer FB emitting the B color fluorescence with the illumination light LU. can do. This principle is also illustrated in FIG. 4, whereby the pixel display lights PB, PG, P of the BGR are displayed.
R is obtained.

The display devices of the third and fourth embodiments of the present invention, which will be described later, are constructed based on such a principle of wavelength conversion of ultraviolet light.

<Third Principle of the Invention> Further, according to the present invention, two-dimensional illumination light obtained by using white light (for example, light emission from a white fluorescent tube) including wavelengths from the ultraviolet region to the visible light region. Can also be used to excite each of the RGB fluorescent layers. By receiving the white light by providing the fluorescent layers for each of RGB, (1) the ultraviolet light component in the illumination light contributes to the emission of any of the RGB fluorescent layers, and (2) the visible wavelength in the illumination light. The wavelength component shorter than the G color in the region contributes to the emission of light from the G color fluorescent layer and the R color fluorescent layer, and (3) from the G color to the R color in the visible wavelength region in the illumination light. The wavelength component contributes to the light emission of the R color fluorescent layer.

Therefore, in this embodiment, the utilization efficiency of the illumination light is high in a wide wavelength range.

Here, "pseudo white light" obtained by the combination of the blue LED and the yellow fluorescent layer is referred to as "color filter".
It should be noted that the principle is completely different from the conventional technique in which the RGB display is performed through. In this conventional technique, even if the illumination light is artificially white, the RGB light passes through the color filter.
Therefore, only the wavelength components of the colors of the respective filters of the illumination light contribute to the display, and the components of the wavelength range of the respective colors are cut by the respective color filters.

On the other hand, according to the third principle of the present invention,
The short-wavelength side component of white light contributes to the generation of RGB color light in each of the RGB fluorescent layers. Therefore, color display light with high brightness and high color purity can be obtained as compared with the prior art.

The fifth and sixth embodiments described later are constructed based on this principle.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION <First Embodiment><SchematicConfiguration> FIG. 6 shows a mobile phone 1 as an information terminal incorporating a flat panel type display device according to a first embodiment of the present invention. FIG. 7 is an external view, and FIG. 7 is a block diagram of its main part. The configurations of FIGS. 6 and 7 are the same in the mobile phones of other embodiments described later.

In FIG. 6, in the mobile phone 1, a display surface of a main body 100 of a liquid crystal display device (LCD) as a flat panel type display device is exposed on the front surface of a housing 2, and operation keys are located below the display surface. Six arrays are provided. The semiconductor microphone 4 and the speaker 5 are separately arranged above and below the housing 2, and an extendable antenna 9 projects from the housing 2.

As shown in FIG. 7, the antenna 9 is connected to the microcomputer 7 via the communication controller 3. The microphone 4, speaker 5 and operation key 6 are also connected to the microcomputer 7.

The LCD main body 100 is a transillumination type display which constitutes a TFT liquid crystal display panel, and a backlight structure 200 is attached to the back surface thereof. LCD
The main body 100 and the backlight structure 200 are connected to the microcomputer 7 via the LCD control circuit 10. The image information for each pixel expanded in the image memory 8 is given to the LCD control circuit as an RGB image signal IS, and the voltage applied to the liquid crystal layer corresponding to each pixel of the LCD body 100 is included in the RGB image signal IS. R of each pixel
By controlling according to the GB digital brightness level,
A two-dimensional full-color image using the RGB three primary colors can be displayed on the LCD body 100. This display image may be either a still image or a moving image, and variable image display is realized on the LCD main body 100 by updating the image information developed in the image memory 8.

<Detailed Configuration of LCD> FIG. 8 shows the LCD main body 1
00 and the backlight structure 200 are schematic partial cross-sectional views with an XYZ rectangular coordinate system added. The backlight structure 200 includes a plurality of blue LEDs 201 arranged one-dimensionally in the X direction at the Y direction end (only one blue LED 201 is shown in FIG. 8). The blue LED 201 generates blue illumination light LB0, which is incident on one end side of the light guide plate 210 spreading in the XY plane direction. This light guide plate 210 converts the illumination light LB0 as a chain of spot light into a two-dimensionally almost uniform illumination light LB and diffuses it in the Z direction, for example, by distributing a light diffusing material therein. In order to prevent the illumination light LB0 that has entered the light guide plate 210 from being dissipated in a direction other than toward the LCD body 100, each side surface (except the right surface) and the bottom surface of the light guide plate 210 in the directional relationship of FIG. Has become. The inside of the light guide plate 210 has a light diffusing function, but is colorless and transparent in terms of color properties. Therefore, the illumination light LB that is incident on the LCD body 100 from the light guide plate 210 and is substantially uniform in two dimensions is also blue light.

The LCD main body 100 has a laminated structure, and this laminated structure includes a first polarizing layer 101, a glass substrate (or a flexible plastic substrate) 102, from the side of the backlight structure 200 closer to the light guide plate 210. The matrix pattern of the first transparent electrode 104 driven by the pixel selection drive layer 103 including the scanning signal line and the TFT drive circuit, the liquid crystal layer 105, and the transparent common electrode layer 10.
6, RGB light generation layer 110, glass substrate (or flexible plastic substrate) 107 and second polarizing layer 1
Has 08.

The illumination light LB is linearly polarized in the first direction (for example) the X direction in the first polarizing layer 101, passes through the glass substrate 102 and the transparent electrode 104 for each pixel, and reaches the liquid crystal layer 105. In the liquid crystal layer 105, the liquid crystal layer 1 is controlled by controlling the voltage applied between the transparent electrode 104 and the common electrode 106 for each pixel according to the image signal.
The orientation of the liquid crystal molecule group in 05 changes. Second polarizing layer 1
The polarization direction of 08 is orthogonal to the first polarization layer 101, and the amount of light passing through the second polarization layer 106 changes according to the alignment state of the liquid crystal in the portion corresponding to each pixel in the liquid crystal layer 105. To do. That is, this control structure has the liquid crystal layer 1 provided between the two transparent electrode layers 104 and 106 facing each other.
05 and 2 provided on the upper and lower sides of the liquid crystal layer 105, respectively.
The two polarizing layers 101 and 108 form a liquid crystal control structure that controls the output amount of each pixel of RGB image light in response to the RGB image signal IS.

The illumination light LB that has undergone the intensity change for each pixel in this way enters the next RGB light generation layer 110. The RGB light generation layer 110 is covered with a transparent protective layer 111, and each of the RGB pixel areas AR, AG, A.
B is periodically repeated and arranged two-dimensionally (FIG. 9).
reference). In this embodiment, the set of pixel areas AR, AG, and AB is a matrix array (so-called RGB mosaic array) in which each row is shifted, but the pixel areas AR, AG, and
Various sequences can be applied as a mode of the sequence of AB.

Of the pixel areas AR, AG, and AB, the unit pattern of the R fluorescent layer FR is formed in the R pixel area AR, and the unit pattern of the G fluorescent layer FG is formed in the G pixel area AG. . These unit patterns have a substantially rectangular mat shape in the XY plane direction. On the other hand, no layer having a wavelength conversion function is formed in the B pixel area AB. Therefore, the B pixel region AB in this embodiment has the same function as a simple “transparent window” optically. In addition, each pixel area AR,
The light-shielding layer 11 so that the space between AG and AB is filled in the XY directions.
A matrix pattern of 2 (black mask) is formed.

The G pixel region of the RGB light generation layer 110 receives the blue illumination light LB to generate G-color fluorescence FG, and this G-color fluorescence FG passes through the second polarizing layer 108 to generate G-color. Is visually recognized as the display of the pixel. Similarly, the R pixel region receives the blue illumination light LB to generate R color fluorescence FR, and this R color fluorescence FR is visually recognized as a display of the R color pixel via the second polarizing layer 108. It The B pixel region only transmits the illumination light LB, and is therefore visually recognized as a display of B color pixels through the second polarizing layer 108. This principle has already been described with reference to FIGS. 1 and 2.

Therefore, by applying a voltage corresponding to the brightness level designated by the RGB digital image signal IS of FIG. 7 between the transparent electrode 104 and the common electrode 106 for each pixel of RGB, the pixels of RGB three primary colors are It is possible to display an image using a combination of full-color RGB image lights.

The blue LE used in this embodiment is
An example of the emission spectrum of D201 and the emission spectra of the G fluorescent layer FG and the R fluorescent layer FR is shown in FIG.

In this display structure, the blue L
Unlike the conventional method in which the illumination light of the ED is converted to white light using a yellow fluorescent plate and then RGB light is colored for each pixel through white light through a color filter using pigments or dyes, there is less loss of brightness. In addition, it is possible to display a color image with low power and high brightness. Since the RG color is a fluorescent color, its purity is also high, and since the B color uses the emission color of a blue LED, the B color is also highly pure.

That is, in the case of the conventional structure in which the white light is colored by passing through the color filter, when the energy of the illumination light is E, only the wavelength portion EP of the energy E that passes through the color filter is displayed. Contribute to. In order to increase the color purity, it is necessary to narrow the "window in the wavelength space" through which the light component of the desired color (for example, G color) of the energy band of the material forming the color filter is transmitted. , So that the transmittance R =
Ep / E decreases. Therefore, the energy E of the illumination light must be increased in order to secure the brightness. That is, there is a trade-off relationship between the improvement of color purity of color display and the suppression of electric power for obtaining illumination light.

On the other hand, in the case of coloring with fluorescence as in this embodiment, the color purity is determined by the emission wavelength of the fluorescent material, and the energy E of the illumination light is increased in order to improve the color purity. Need not be increased. Particularly, in the conventional technique for obtaining white light by mixing yellow fluorescence with light from the blue LED, the R color purity is improved because the content of the R color wavelength component is small as described in FIG. It is difficult. On the other hand, in this embodiment, since the B color light from the blue LED is received and converted into the R color, the purity of the R color is not significantly inferior to that of the G color, and each of the RGB colors is not deteriorated. It is possible to ensure a balanced purity for the components.

By incorporating a light diffusing material into at least one of the R fluorescent layer FR and the G fluorescent layer FG,
The efficiency of conversion into fluorescence can be further increased. When the light diffusing material is mixed in the fluorescent layer as described above, the polarization direction may be disturbed in the fluorescent layer.
8 is preferably provided between the common electrode 106 and the RGB light generation layer 110.

As described above, since the backlight structure 100 composed of the LED and the light guide plate can be made relatively thin, the thickness of the entire display does not increase.

Further, since the mobile phone 1 (more generally, a mobile type information terminal) can obtain a display with low power, high brightness and high color purity, it is possible to display a clear image for a long time even outdoors. Has the advantage that

RGB light generation layer 11 in this embodiment
The pattern of 0 is obtained by modifying the dyeing method or pigment dispersion method used for manufacturing the LCD color filter, forming a resin layer containing a fluorescent material instead of the dye or pigment, and patterning it by photolithography or the like. Can be obtained by It is also possible to obtain it by applying the ink mixed with the fluorescent material in a pattern on the substrate 102 using an offset printing technique or a precision printer of the inkjet type.

<Second Embodiment> FIG. 10 is a schematic partial sectional view of an LCD main body 100a and a backlight structure 200 of a mobile phone according to a second embodiment of the present invention. This structure is different from the structure (FIG. 8) in the first embodiment in that the B auxiliary layer 11 is provided in the pixel regions AB, AG, and AR.
3B, the G auxiliary layer 113G and the R auxiliary layer 113R are respectively formed, and the rest of the configuration is the same as the structure of the first embodiment. Among the auxiliary layers 113R to 113B, the G auxiliary layer 113G is provided on the emission side of fluorescence from the G fluorescent layer FG, and the R auxiliary layer 113R is provided on the emission side of fluorescence from the R fluorescent layer FR.

Each of the auxiliary layers 113R to 113B may be a color filter film containing a pigment or a dye,
It may be a diffusion layer in which a colorless light diffusing material is mixed.

The color filter films are used as the auxiliary layers 113R to 113B for the R color, the G color and the B color, respectively.
This is for finely adjusting the color tone. Therefore, even when such a color filter film is used in combination, the content of the pigment or dye can be reduced as compared with the method of coloring the RGB light only with the color filter, and the loss of the brightness of the RGB color light is relatively small. It can be small.

When the auxiliary layers 113R to 113B are configured as diffusion layers, the respective pixel areas AR, AG, A are formed.
The viewing angles of the R light, G light, and B light emitted from B can be widened. Thus, the auxiliary layers 113R to 113B
Is a diffusion layer, the second polarizing layer 10
By providing 8 between the common electrode 106 and the RGB light generation layer 110, there is an advantage that the output light amount does not decrease even if the polarization direction is disturbed by diffusion in the fluorescent layer.

Further, both the diffusing material and the colorant may be mixed in the auxiliary layers 113R to 113B so that the diffusing layer serves also as the color filter, or a double layer of the diffusing layer and the color filter layer may be formed.

Further, in any case, the auxiliary layers 113R to 113R ...
Only one or two of 113B may be provided.

<Third Embodiment> FIG. 11 is a schematic partial sectional view of an LCD main body 100b and a backlight structure 200b of a mobile phone according to a third embodiment of the present invention. This structure is the structure in the first embodiment (FIG. 8).
The difference is that the backlight structure 200b uses a one-dimensional array in the X direction of ultraviolet LEDs 202 that generate ultraviolet light as a light source, and the LCD body 100b.
The unit pattern of the B fluorescent layer FB that emits B-color fluorescence is formed in each of the B pixel regions AB.

As already described with reference to FIGS. 3 and 4, the ultraviolet light has a wavelength shorter than the wavelength of each light of RGB, and the R fluorescent layer FR, the G fluorescent layer FG, and the B fluorescent layer. The layer FB receives the two-dimensional illumination light LU obtained by diffusing the illumination light (ultraviolet light) LU0 generated from the ultraviolet light LED 202 by the light guide plate 210, and emits R, G, and B color fluorescence, respectively. Occur. Then, in the structure of the third embodiment, these R, G, and B color fluorescences are used as display light of an image for each pixel.

Also in the structure of the third embodiment, compared with the case where the RGB light is obtained by passing the white light obtained from the blue light by the yellow fluorescent plate through the color filter, the variable color of low power and high brightness is obtained. Images can be displayed.

By mixing a light diffusion material into each of the R fluorescent layer FR, the G fluorescent layer FG and the B fluorescent layer FB,
You may improve the conversion efficiency to fluorescence in each. In this case, the polarizing layer 108 and the common electrode 106 and R
Similar to the first embodiment, it can be modified so as to be provided between the GB light generation layer 110 and the GB light generation layer 110.

<Fourth Embodiment> FIG. 12 is a schematic partial sectional view of an LCD main body 100c and a backlight structure 200b of a mobile phone according to a fourth embodiment of the present invention. This structure corresponds to that of the third embodiment (see FIG.
In 1), the fluorescent layers FR, FG, F on the R pixel area AR, the G pixel area AG, and the B pixel area AB, respectively.
The auxiliary layer 113R and the auxiliary layer 1 are provided on the fluorescence emission surface side of B, respectively.
13G and the auxiliary layer 113B are formed. The rest of the configuration and modifications are the same as the structure in the third embodiment.

As in the second embodiment, the auxiliary layers 113R to 113B in the structure of the fourth embodiment may be a color filter film, a diffusion layer, a combination thereof, or a double layer.

<Fifth Embodiment> FIG. 13 is a schematic partial sectional view of an LCD main body 100b and a backlight structure 200c of a mobile phone according to a fifth embodiment of the present invention. This structure is the structure in the third embodiment (see FIG.
The difference from 1) is that the backlight structure 200 uses a long white fluorescent tube 203 extending in the X direction as a light source of white illumination light including wavelengths from the ultraviolet region to the visible light region.
This is the point where c is used.

As described above as the "third principle of the invention", the white light LW0 from the white fluorescent tube 203 has a wide spectrum from the ultraviolet region to the RGB visible light region, and the R fluorescent layers FR, G Fluorescent layer FG and B fluorescent layer F
B receives the two-dimensional illumination light LW obtained by diffusing the white light LW0 by the light guide plate 210, and receives R color and G, respectively.
Generates fluorescence of colors B and B. Then, in the structure of the fifth embodiment, the R, G, and B color fluorescences are used as display light of an image for each pixel.

Also in the structure of the fourth embodiment, the power consumption is lower than that of the prior art in which the pseudo white light obtained from the blue light through the yellow fluorescent plate is passed through the color filter to obtain the RGB light. "Third principle of the invention" means that it is possible to display color images with high brightness and high color purity.
As already explained in.

As in the third embodiment, the efficiency of conversion into fluorescence in each of the R fluorescent layer FR, the G fluorescent layer FG, and the B fluorescent layer FB is improved by mixing a light diffusing material. You may let me. In this case, the polarization layer 108 can be modified so as to be provided between the common electrode 106 and the RGB light generation layer 110, similarly to the third embodiment.

<Sixth Embodiment> FIG. 14 is a schematic partial sectional view of an LCD main body 100c and a backlight structure 200c of a mobile phone according to a sixth embodiment of the present invention. This structure corresponds to the structure in the fifth embodiment (see FIG.
3) Among the R pixel area AR, the G pixel area AG, and the B pixel area AB, the respective fluorescent layers FR, FG, F
The auxiliary layer 113R and the auxiliary layer 1 are provided on the fluorescence emission surface side of B, respectively.
13G and the auxiliary layer 113B are formed. The rest of the configuration and modifications are the same as the structure of the fifth embodiment.

As the auxiliary layers 113R to 113B in the structure of the sixth embodiment, a color filter film, a diffusion layer, a combination thereof, or a double layer can be used as in the fourth embodiment.

<Modification> In the above embodiment, RG is used.
When the maximum brightness of each pixel of B is different, it is possible to use a filter film or a diffusion layer as an auxiliary layer so that the maximum brightness is structurally almost the same. It is also possible to balance the maximum brightness of each pixel, that is, the white balance. Ie LCD
A gamma correction circuit is incorporated in the control circuit 10 as hardware or software, the RGB image signal is converted into each component so that the RGB brightness is balanced in the gamma correction curve, and the converted RGB image signal is displayed on the LCD body. It may be given to 100 or the like.

The present invention is mainly directed to color display by fluorescence emission, and the structure for changing the light amount of each pixel according to the image signal level can be applied regardless of the LCD structure. That is, coupled to the RGB light generation layer,
Various control structures can be used to control the output amount of each pixel of RGB image light in response to an image signal.

As the blue light source and the ultraviolet light source, a semiconductor light emitting element such as an LED, a cold cathode ray tube or a fluorescent tube can be used.

[0071]

As described above, according to the inventions of claims 1 to 6, pixel display of RG color is performed using R fluorescence and G fluorescence corresponding to wavelength conversion of blue illumination light. , B-color pixel display can be performed by using the color of illumination light, so that the RGB display light has high luminance and high color purity, and since light loss is small, display can be performed with low power. is there.

Further, in the flat panel display, it is necessary to reduce the thickness in the depth direction. Therefore, as in the case of a color CRT tube, a large thickness in the depth direction as a deflection space for the electron beam is used, and the RGB fluorescent layer is excited by scanning with the deflected electron beam to generate RGB.
It is not possible to realize pixel emission. On the contrary,
In the inventions of claims 1 to 6, since it is not necessary to periodically spatially deflect the electron beam or the like, it is possible to display a high-luminance color image while maintaining flatness.

In particular, according to the second aspect of the invention, by including a diffusing material in at least one of the R fluorescent layer and the G fluorescent layer, the conversion efficiency into fluorescence can be particularly enhanced.

In particular, according to the invention of claim 3, fine color adjustment is performed by at least one of the R color filter layer arranged on the R fluorescent layer and the G color filter layer arranged on the G fluorescent layer. Since the RG color is obtained by fluorescence, the color can be finely adjusted without increasing the loss of the light amount.

According to the fourth aspect of the invention, by forming the light diffusion layer in the B pixel region, the efficiency of conversion into fluorescence can be particularly enhanced.

In particular, according to the invention of claim 5, since the B color filter layer is formed in the B pixel area, the color can be finely adjusted without increasing the loss of the light quantity.

According to the seventh aspect of the present invention, since the RGB color pixel display is performed by using the respective RGB fluorescence corresponding to the wavelength conversion of the ultraviolet illumination light, the RGB display light has high brightness and color. Since the purity is high and the loss of light amount is small, it is possible to display with low power.

Unlike the CRT tube, it is also the same as the invention of claim 1 that it is possible to display a high-intensity color image while maintaining flatness.

According to the eighth aspect of the present invention, since the illumination light including the ultraviolet region to the visible light region is wavelength-converted by each of the RGB fluorescent layers to display RGB color pixels, a wide wavelength range of the illumination light is obtained. Is utilized, RGB display light with high brightness and high purity can be obtained, and since there is little loss of light quantity, display with high brightness and high color purity can be performed with low power.

According to the ninth and tenth aspects of the invention, it is possible to obtain an information terminal (particularly a mobile phone) using the display device having the above advantages as a display unit.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a first principle of the present invention.

FIG. 2 is a conceptual diagram of an optical spectrum for explaining the first principle of the present invention.

FIG. 3 is an explanatory diagram of a second principle of the present invention.

FIG. 4 is a conceptual diagram of an optical spectrum for explaining the second principle of the present invention.

FIG. 5 is a diagram showing an example of emission spectra of a blue LED and emission spectra of a G fluorescent layer and an R fluorescent layer.

FIG. 6 is an external view of a mobile phone according to an embodiment of the present invention.

FIG. 7 is a block diagram of a mobile phone according to an embodiment.

FIG. 8 is a schematic partial cross-sectional view showing a display structure in the mobile phone of the first embodiment.

FIG. 9 is a partial plan view schematically showing a pixel array.

FIG. 10 is a schematic partial cross-sectional view showing a display structure in the mobile phone of the second embodiment.

FIG. 11 is a schematic partial cross-sectional view showing a display structure in the mobile phone of the third embodiment.

FIG. 12 is a schematic partial cross-sectional view showing the display structure of the mobile phone of the fourth embodiment.

FIG. 13 is a schematic partial cross-sectional view showing a display structure in the mobile phone of the fifth embodiment.

FIG. 14 is a schematic partial cross-sectional view showing the display structure of the mobile phone of the sixth embodiment.

FIG. 15 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

100 LCD body 110 RGB light generation layer 200 backlight structure 201 blue LED 202 UV LED 203 white fluorescent tube LB Blue illumination light LU UV illumination light AB B color pixel area GG color pixel area ARR color pixel area FB B color fluorescent layer FG G color fluorescent layer FR R color fluorescent layer PB B color pixel display light PG G color pixel display light PR R color pixel display light IS RGB image signal

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G09F 9/30 349 G09F 9/30 349Z H04N 9/30 H04N 9/30 F term (reference) 2H048 BB02 BB08 BB26 BB42 2H088 EA02 HA10 HA12 HA15 HA18 HA28 MA01 MA05 MA20 2H091 FA02X FA08X FA08Z FA43Z FA45Z FD08 FD21 FD24 GA16 LA11 LA15 LA30 MA10 5C060 BC01 DA02 HA18 HD07 JA00 5C094 AA07 AA08 AA22 BA43 CA24 ED20 FA43 CA24 ED

Claims (10)

[Claims] 1. A flat panel type color image display device comprising: an illuminating section for generating blue illuminating light spread two-dimensionally; and an R fluorescent layer for converting the illuminating light into R (red) light. The R pixel region, the G pixel region in which the G fluorescent layer that converts the illumination light into the G (green) light is formed, and the illumination light
An RGB light generation layer that has a two-dimensional repetitive array with a B pixel region that transmits as (blue) light, and obtains RGB image light by applying the illumination light to the repetitive array; And a control structure for controlling an output amount of each of the RGB image lights for each pixel in response to an image signal, the flat panel color image display device. 2. The color image display device according to claim 1, wherein at least one of the R fluorescent layer and the G fluorescent layer contains a light diffusing material. 3. The color image display device according to claim 1 or 2, wherein the RGB light generation layer is arranged on the R color filter layer and the G color layer. A flat panel type color image display device further comprising at least one of a G color filter layer. 4. The color image display device according to claim 1, wherein the RGB light generation layer further includes a light diffusion layer formed in the B pixel region. Flat panel type color image display device. 5. The color image display device according to claim 1, wherein the RGB light generation layer further comprises a B color filter layer formed in the B pixel region. Flat panel type color image display device. 6. The color image display device according to claim 1, wherein the control structure includes a liquid crystal layer provided between first and second transparent electrode layers facing each other, and the liquid crystal. First and second layers provided on the upper and lower sides of the layer, respectively
A polarizing layer, and the RGB in response to the image signal.
A flat panel color image display device having a liquid crystal control structure for controlling the output amount of image light for each pixel. 7. A flat panel color image display device, comprising: an illuminating section that generates ultraviolet light that has spread two-dimensionally as illuminating light; and an R fluorescent layer that converts the illuminating light into R (red) light. The formed R pixel area, the G pixel area in which the G fluorescent layer that converts the illumination light into G (green) light is formed, and the illumination light in B
RG that has a two-dimensional repetitive array with a B pixel region in which a B fluorescent layer for converting into (blue) light is formed, and obtains RGB image light by applying the illumination light to the repetitive array
A flat panel color image, comprising: a B light generation layer; and a control structure coupled to the RGB light generation layer and controlling an output amount of each pixel of the RGB image light in response to an image signal. Display device. 8. A flat panel type color image display device, comprising: an illuminating section for generating illuminating light that spreads two-dimensionally including wavelengths from an ultraviolet region to a visible light region; and R (red) for the illuminating light. An R pixel region formed with an R fluorescent layer for converting light, a G pixel region formed with a G fluorescent layer for converting the illumination light into G (green) light, and the illumination light with B
RG that has a two-dimensional repetitive array with a B pixel region in which a B fluorescent layer for converting into (blue) light is formed, and obtains RGB image light by applying the illumination light to the repetitive array
A flat panel color image, comprising: a B light generation layer; and a control structure coupled to the RGB light generation layer and controlling an output amount of each pixel of the RGB image light in response to an image signal. Display device. 9. An information terminal using the flat panel type color image display device according to claim 1 for a display section. 10. The information terminal according to claim 9, wherein the information terminal is configured as a mobile phone.