JP2002169105A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device which enables high luminance, high contrast and cost reduction using a simple constitution. SOLUTION: A groove-shaped space 2 is formed in a light-transmissive member 1 comprising glass and the like, and thereafter, a liquid 3, such as water in which black dye is dissolved which cuts off visible light, is injected up to approximately half the volume of the space 2. Subsequently, another light-transmissive member 4 is stuck thereto and the groove-shaped space 2 is covered thereby. Then, a shielding film 5 is formed on the rear surface of the light-transmissive member 1. At this time, no shielding film 5 is formed on a part 5a corresponding to a pixel. With this constitution, when infrared light is irradiated from the rear surface side of the light- transmissive member 1 and the temperature of the liquid 3 which shields the visible light is elevated, the surface tension of the liquid 3 which shields the visible light is changed, the liquid 3 which shields the visible light is moved to the side which is not irradiated with the light and shields the visible light from the rear surface. This result can be obtained by utilizing the property, that when there is gradient of surface tension, the liquid 3 which shields visible light moves from the side of low surface tension to the side of high surface tension. Accordingly, a picture can be displayed by selectively moving the liquid 3 which shields the visible light in plural groove-shaped spaces 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying an image by controlling light emitted from one side of a light transmitting member.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 5-530
No. 25, "Waveguide-type optical switch" A waveguide-type optical switch that switches an optical path using a phase change of a liquid in a gap provided in the middle of a core waveguide caused by applying heat. Japanese Patent Laid-Open Publication No. Hei 6-175052 "Optical switch and optical switch array" An optical switch that switches the optical path by moving a liquid metal installed in the optical path by applying a voltage. * JP-A-8-201856
Patent Document “Waveguide-type optical switch and manufacturing method thereof” A waveguide-type optical switch that switches a propagating optical path by moving a liquid in a slit provided at an intersection of optical paths that intersect each other on a substrate. Etc. have been proposed.

There is a liquid crystal display device as a display device using a liquid as a constituent element. A general liquid crystal display device includes a liquid crystal sealed with a transparent electrode and a light-transmitting member having a polarizing property. In this method, a change in the optical effect of liquid crystal is generated for each pixel by a voltage applied to a transparent electrode, and light is turned on and off in combination with a polarizing translucent member to perform screen display.

As described above, in a normal liquid crystal display device, a polarizing translucent member, that is, a polarizing plate is provided so as to sandwich the liquid crystal panel from both sides, and the display is made by passing through the polarizing plate. The amount of light that contributes is reduced to about 1/3. That is, in the liquid crystal display device, since the deflection plate is used, there is a factor that lowers luminance and contrast in principle.

[0005] A waveguide type optical switch has been reported as a device that uses a liquid in addition to a liquid crystal display device to switch the propagation direction of an optical path (Japanese Patent Laid-Open Nos. 5-53025 and 6-175052). JP-A-8-201856
No.). This is to switch the propagating optical path by moving the liquid in the slit provided at the intersection of the optical paths (waveguides) crossing each other on the substrate. These use refraction and transmission of light when the liquid in the slit moves to the intersection of the optical paths.

[0006]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 5-530 is disclosed.
No. 25, Japanese Unexamined Patent Publication No. Hei 8-201856, uses a refractive index matching liquid substantially equal to a waveguide as a liquid,
By applying heat to the liquid, the liquid is vaporized or agglomerated to generate and extinguish bubbles, thereby changing the refractive index in the gap. However, in this report, it is necessary to provide a heater for applying heat, which complicates the structure.

In JP-A-6-175052, liquid metal, that is, mercury, is used as a liquid, and the liquid is moved by applying a voltage to the liquid to change the refractive index in the gap. However, since this method uses mercury, if the optical switch is damaged, it is not good for the environment. Further, in order to apply a voltage, it is necessary to form electrodes and the like, which complicates the structure.

As described above, it is necessary to form a heater, an electrode, and the like in order to control the movement of the liquid, which complicates the structure and increases the number of forming processes.

[0009] Each of these uses the reflection of the light propagating from the waveguide on the gap wall surface. These elements cannot be formed simply in parallel to the substrate surface because a gap is formed perpendicular to the substrate due to its structure. Further, in a liquid crystal display device, since a deflection plate is used, luminance and contrast are reduced in principle.

Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a display device which can achieve high luminance, high contrast and low cost with a simple configuration.

[0011]

In order to achieve the above-mentioned object, a display device according to the present invention comprises a light-transmitting member, a space formed in the light-transmitting member, and a space filled in the light-transmitting member. It is made of a liquid that blocks visible light that has become movable in space by light emitted from one side of the optical member.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view showing an example of the display device according to the first embodiment of the present invention. FIG. 1 relates to one pixel among many pixels in a display device. In FIG. 1, first, a groove-shaped space 2 is formed in a translucent member 1. The groove-shaped space 2 is formed by a normal semiconductor element forming process, ie, resist coating, exposure,
It can be formed by etching.

As the translucent member 1, a glass substrate generally used in a liquid crystal display device can be used.
The material is not limited to this, and any material may be used as long as it has a property of transmitting light in a visible light region. In addition, any substance may be used as long as it is a substance whose surface changes from hydrophobic to hydrophilic when irradiated with light of a specific wavelength, or a substance whose surface changes from hydrophilic to hydrophobic when irradiated with light of a specific wavelength.

Next, a liquid 3 for blocking visible light is injected into the groove-shaped space 2 formed in the translucent member 1 so as to fill about half of the volume of the groove-shaped space 2. As the liquid 3, water in which a black dye is dissolved can be used, but it is not limited to this, and any liquid that blocks visible light may be used.

Next, another translucent member 4 is adhered to the translucent member 1 having the groove-shaped space 2 formed therein, and the groove-shaped space 2 is formed.
Cover. The translucent member 4 may be made of glass or the like having the same properties as the translucent member 1, but the translucent members 1 and 4 do not have to be made of the same material.

Next, a shielding film 5 is formed in a predetermined pattern on the back surface of the translucent member 1, that is, on the surface to be irradiated with light.
At this time, the shielding film 5 is not formed on the portion 5a corresponding to the pixel. Note that this shielding film 5 is necessary when a backlight is used so as to be used in a liquid crystal display device instead of using a light source for each pixel. When a light source is used independently for each pixel, the shielding film 5 is unnecessary.

In the display device having the above structure, as shown in FIG. 1 and FIG. 3A, the liquid 3 that blocks visible light is irradiated with infrared light from the back side of the light transmitting member 1 to emit visible light. When the temperature of the liquid 3 that blocks the visible light is increased, the surface tension of the liquid 3 that blocks the visible light changes, and the liquid 3 that blocks the visible light moves to the side where the light is not irradiated as shown in FIG. It can move and block visible light from the back. This utilizes the property that the liquid 3 that blocks visible light moves from a side having a lower surface tension to a side having a higher surface tension when there is a gradient of the surface tension. Therefore, an image can be displayed by selectively moving the liquid 3 that blocks visible light in the plurality of groove-shaped spaces 2. In particular, digital character information and image information can be displayed.

Next, the case where various materials are used for the translucent member 1 will be described. When quartz glass is used for the translucent member 1, similarly to the above, by irradiating infrared light, the temperature of the liquid 3 rises, the surface tension changes, and the liquid 3
The visible light from the back surface can be blocked by the movement of the.

When titanium oxide is used for the light-transmitting member 1, the light-transmitting member 1 is irradiated with ultraviolet light,
Liquid 3 that changes the wettability of the translucent member and blocks visible light
The tension at the interface between the liquid and the translucent member changes, and the liquid 3 that blocks visible light moves to the side where light is not irradiated, and can block visible light from the back surface. Therefore, an image can be displayed by selectively moving the liquid 3 that blocks visible light in the plurality of groove-shaped spaces 2.

Next, a second embodiment of the present invention will be described with reference to FIG. 2, parts corresponding to those in FIG. 1 are denoted by the same reference numerals, and duplicate description will be omitted. In the present embodiment, the inner wall of the groove-shaped space 2 (the translucent member 1,
(Surface 4) is coated with a substance whose surface changes from hydrophilic to hydrophobic by irradiating light of a specific wavelength. In FIG. 2, a sol-gel film 6 of titanium oxide is coated as the above substance.

According to the present embodiment, by irradiating ultraviolet light to change the wettability of the translucent member, the tension at the interface between the liquid 3 that blocks visible light and the translucent member changes. ,
The liquid 3 can be moved to the side where light is not irradiated, and the visible light from the back surface can be blocked.

[0022]

As described above, according to the first aspect of the present invention, unlike the conventional liquid crystal display device, since a component such as a polarizing plate for reducing the amount of light is not included, high brightness and high brightness can be obtained with a simple configuration. A display device with contrast can be obtained.

According to the second and fourth aspects of the invention, the surface of the translucent member or the inner surface of the space changes from hydrophobic to hydrophilic by irradiating light of a specific wavelength, and the liquid moves. Thus, it is possible to obtain a display device which is not affected by disturbances such as an electric field and a magnetic field.

According to the third and fifth aspects of the invention, the surface of the translucent member or the inner surface of the space changes from hydrophilic to hydrophobic by irradiating light of a specific wavelength, and the liquid moves. In addition, it is possible to obtain a display device which is not affected by disturbances such as electric and magnetic fields.

According to the sixth aspect of the present invention, a heater for applying heat is provided in order to move the liquid in space by irradiating infrared light as light of a specific wavelength and applying heat to the liquid. There is no need, the structure can be simplified, and the cost can be reduced.

According to the present invention, since the liquid is moved in the space by irradiating ultraviolet light as light of a specific wavelength, there is no need to provide a heater for applying heat, and the structure is simplified. Cost can be reduced.

According to the eighth aspect of the present invention, since the glass substrate is used for the light-transmitting member, the light-transmitting member is transparent in the visible light region, does not obstruct light from the back surface, and further has a light-transmitting member. A groove-shaped space can be easily formed therein.

According to the ninth aspect of the present invention, since titanium oxide is used for the light-transmitting member or the inner surface of the space, the light is irradiated with light in a short wavelength region such as ultraviolet light, so that it becomes hydrophilic or hydrophobic. Can be obtained.

According to the tenth aspect of the present invention, a light-shielding film for shielding light is provided on a portion of one surface of the translucent member other than a portion corresponding to a part of the space, so that all pixels can be covered. One backlight light source can be used.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a display device according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a display device according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram illustrating a display state and a non-display state of a pixel.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 translucent member 2 grooved space 3 liquid that blocks visible light 4 translucent member 5 shielding film 6 sol-gel film of titanium oxide

Claims (10)

[Claims] A light-transmitting member; a space formed in the light-transmitting member; and a space filled in the light-transmitting member and moved in the space by light irradiated from one surface side of the light-transmitting member. And a liquid that blocks visible light. 2. The display device according to claim 1, wherein the translucent member is made of a substance whose surface changes from hydrophobic to hydrophilic when irradiated with light of a specific wavelength. 3. The display device according to claim 1, wherein the translucent member is made of a substance whose surface changes from hydrophilic to hydrophobic when irradiated with light of a specific wavelength. 4. The display device according to claim 1, wherein a substance whose surface changes from hydrophobic to hydrophilic is formed by irradiating light of a specific wavelength to the inner surface of the space. 5. The display device according to claim 1, wherein a substance whose surface changes from hydrophilic to hydrophobic is formed by irradiating light of a specific wavelength to the inner surface of the space. 6. The display according to claim 1, further comprising irradiation means for irradiating infrared light as light to be irradiated from one surface side of the translucent member and applying heat to the liquid. apparatus. 7. The display device according to claim 1, further comprising irradiation means for irradiating ultraviolet light as light irradiated from one surface side of said translucent member. 8. The display device according to claim 1, wherein the light-transmitting member is a glass substrate. 9. The display device according to claim 1, wherein the substance that changes from hydrophilic to hydrophobic is titanium oxide. 10. The light-transmitting member according to claim 1, wherein a light-shielding film is provided on a portion of the one surface of the one surface except for a portion corresponding to a part of the space. The display device according to item.