JP2000010491A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device which always maintains a clean display face and which can show a sharp display. SOLUTION: UV rays in the rays emitted from a surface light source 30 are transmitted through a liquid crystal panel 20 and irradiated to a photocatalyst layer 50 to activate a photocatalyst. Finger prints (ammonia, org. substances or the like) depositing in the case of operation or aldehydes depositing due to smoking in a car are oxidized and decomposed by a photocatalytic reaction and finally decomposed into water, carbon dioxide and nitric acid which are removed from the surface of this display device. Thus, the surface of the display device can be always maintained clean without cleaning and a sharp image can be continuously displayed over a long time.

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 various information.

[0002]

2. Description of the Related Art OA equipment, video cameras, car navigation systems, laptop computers, etc., which have a backlight as a display device, such as a liquid crystal display device with a backlight, are light, thin and have low power consumption. Widely used as a monitor. In addition, touch panels in which a detection layer is provided in the liquid crystal display device so that an input can be performed on a display surface have been widely used.

[0003]

By the way, a photocatalyst is applied to the display surface of a display (display element), and dirt which is inadvertently attached to the display surface or inevitably adhered to a touch panel or the like by light from the outside. It can be removed and decomposed. However, for example, in the case of a vehicle, an ultraviolet transmission prevention glass is often used so that ultraviolet light from the outside does not enter the inside of the vehicle, and in the case of a display in a vehicle interior, ultraviolet light for effectively exerting a photocatalytic effect is used. It cannot be expected to be obtained from external natural light. In addition, necessary external light may not be obtained even in a display other than the in-vehicle display. In such a case, the function of the photocatalyst cannot be exhibited.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to always provide a display surface side even when light for exhibiting the function of a photocatalyst does not enter from the outside. An object of the present invention is to provide a display device capable of maintaining a clean surface and displaying a clear image.

[0005]

According to a first aspect of the present invention, there is provided a display device having an active light emitting portion, wherein a photocatalytic layer is formed on a display surface side surface.

According to the first aspect of the present invention, since the photocatalyst layer is formed on the display surface side surface, the photocatalyst is activated by the light emitted from the active light emitting portion in the display device, and the display is performed by the action of the photocatalyst. The display surface of the device can be kept clean at all times.

Here, the active light emitting section means a light emitting section which emits light by itself, and excludes a reflection type (light receiving type) which reflects light from the outside. The light emitted from the light emitting unit includes light having a wavelength that allows the photocatalyst to function.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a display device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a display device 10 according to the first embodiment of the present invention. The display device 10 is a so-called touch panel type liquid crystal device, is disposed on a dash panel 12 of a vehicle, and is used as a common input and display device for various devices. The various devices include an audio device, an air conditioner, a navigation device, and the like.
Switch between air conditioning and navigation and display corresponding information. For example, when air conditioning is selected on the display device (touch panel), an air conditioning control screen is displayed on the display device 10, and the air conditioning device is controlled in accordance with an operator's instruction (touch operation on the display device). When the navigation is selected, a navigation image is displayed, and the navigation image is displayed in accordance with an operator's instruction. In FIG. 1, a navigation function is selected by a touch operation of the display device 10, and a map of the entire Kanto region is displayed in the display device 10.

The configuration of the display device 10 will be described with reference to FIG. The display device 10 includes a surface light source 30, a liquid crystal panel 20, polarizing plates 42 and 44 disposed on both sides of the liquid crystal panel 120, a detection layer 70 adhered to the polarization plate 44, and a detection layer 70. And a photocatalyst layer 50 disposed on the surface.

The surface light source 30 is composed of a cold cathode fluorescent lamp, a light guide plate and the like. This function is a diffusion element that applies the light of a cold cathode fluorescent lamp, which is almost a linear light source, from the end face of the light guide plate, propagates the light in the light guide plate by total reflection, and applies the emitted light to the light guide plate so as to be uniform. To create a surface light source. The liquid crystal panel 20 is composed of thin film transistors (TFTs) in a matrix on a transparent glass substrate.
Matrix substrate 24 on which a transparent pixel electrode is disposed, a twisted nematic (TN) liquid crystal 26 having a twist angle of approximately 90 °, a color filter substrate 28 on which a transparent common electrode and a color filter are formed, and both substrates 2
Sealant 29 for bonding liquid crystals 4 and 28 and sealing liquid crystal
It consists of. The polarizing plates 42 and 44 have a transmission axis of 9
The liquid crystal panel 20 is staggered by 0 °.

The detection layer 70 is made of a flexible resin film and a protective film, and infrared rays from a light source (not shown) disposed at the end portion pass through the resin film in the X direction (in the figure). Direction perpendicular to the paper surface) and Y direction (vertical direction in the figure)
And is received by a light receiving unit (not shown) provided at the opposite end. The operator operates the display device 1
When touching the surface of No. 0, the detection layer 70 of the touched portion is depressed,
The transmission of the infrared rays is hindered. The light receiving portion of the relevant portion that has received the infrared ray transmits a signal indicating that the light cannot be received, and based on this signal, the portion touched by the operator on the liquid crystal display device is detected.

The photocatalyst layer 50 is provided on the surface side of the detection layer 70.
Are formed. The photocatalyst layer 50 is formed by adding TiO2 to the surface of the detection layer 70 in the form of a thin film by sputtering, vapor deposition or the like. Here, it is added as a thin film,
It is also possible to add a thick film.

In the display device of the present embodiment, since the ultraviolet rays of the light rays emitted from the surface light source 30 pass through the liquid crystal display device and irradiate the photocatalyst layer 50, the photocatalyst of the photocatalyst layer is activated. In addition, fingerprints (ammonia, organic substances, etc.) adhered during the above-described operation and aldehydes adhered by smoking in the vehicle are oxidized and decomposed by a photocatalytic reaction, and finally converted into water, carbon dioxide, and nitric acid. Remove from equipment surface. Therefore, the surface of the display device is always kept clean without performing cleaning, and it is possible to keep displaying a clear image for a long time. Here, in a vehicle, even if a photocatalyst is provided on the surface of the display device, the front window, the rear window, and the side window use ultraviolet absorbing glass. 50 cannot be activated. But,
In the present embodiment, the photocatalyst can be activated by light from the surface light source 30 provided in the liquid crystal display device 20.

Next, a display device according to a second embodiment of the present invention will be described with reference to FIG. In the first embodiment described above, the configuration of the present invention is applied to a touch panel type liquid crystal display device. However, in the second embodiment, the configuration of the present invention is applied to a normal liquid crystal display device.
That is, as shown in FIG. 3, the display device is provided with the surface light source 30, the liquid crystal panel 20, the polarizing plates 42 and 44 provided on both sides of the liquid crystal panel 20, and the surface of the polarizing plate 44. Photocatalyst layer 50. The photocatalyst layer 50 is made of TiO2
On the surface of the polarizing plate 44 in a thin film shape by sputtering, vapor deposition, or the like.

In the display device according to the second embodiment, since the ultraviolet rays among the light rays emitted from the surface light source 30 pass through the liquid crystal display device and irradiate the photocatalyst layer 50, the photocatalyst of the photocatalyst layer is activated. Then, ammonia, organic substances, and aldehydes adhered by smoking are oxidized and decomposed by a photocatalytic reaction, and finally converted into water, carbon dioxide, and nitric acid, and removed from the surface of the display device. Therefore, the surface of the display device is always kept clean without performing cleaning, and it is possible to keep displaying a clear image for a long time. Particularly, in a vehicle, the photocatalyst layer 50 of the display device cannot be activated by natural light from the outside, but in the present embodiment, the photocatalyst is activated by light from the surface light source 30 provided in the liquid crystal display device 20. be able to.

Next, a display device according to a third embodiment of the present invention will be described with reference to FIG. In the first and second embodiments described above, the configuration of the present invention is applied to a liquid crystal display device. In the third embodiment, the configuration of the present invention is applied to an electroluminescence or plasma display. That is, as shown in FIG. 4, the display device includes an electroluminescence (or plasma display) 60 and a photocatalyst layer 50 disposed on the surface of the electroluminescence 60. Photocatalyst layer 50
Is formed by adding TiO2 to the surface of the electroluminescence 60 in the form of a thin film by sputtering, vapor deposition or the like.

In the display device according to the third embodiment, an electroluminescence (or plasma display) 6
Ultraviolet rays applied to the photocatalyst layer 50 out of the rays irradiated from 0 activate the photocatalyst of the photocatalyst layer, and oxidize and decompose ammonia, organic substances, and aldehydes attached to the surface of the display device by a photocatalytic reaction, Finally, it is converted to water, carbon dioxide, and nitric acid, and is removed from the surface of the display device. Therefore, the surface of the display device is always kept clean without performing cleaning, and it is possible to keep displaying a clear image for a long time. In particular, in the case of natural light from the outside in vehicles,
The photocatalyst layer 50 of the display device cannot be activated. However, in the present embodiment, the photocatalyst can be activated by the light from the electroluminescence (or plasma display) 60 provided in the liquid crystal display device 20.

In the above-described embodiment, TiO2 is used as a photocatalyst.
Various materials can be used as long as they can be decomposed. For example, Ti, Cu, Zn, La, Mo, V, Sr, Ba,
It can be composed of at least one selected from the group consisting of oxides of Ce, Sn, Fe, W, Mg, or Al, and noble metals. Furthermore, in the above-described embodiment, the photocatalyst is directly adhered to the display surface in a thin film form. However, the photocatalyst is supported on an adsorbent such as silica gel, or is supported on a film such as a resin. It is also possible to adhere.

In the above-described embodiment, the photocatalyst is provided on the surface of the liquid crystal display, the electroluminescent plate, or the plasma display plate. However, the photocatalyst can be attached to the surface of the CRT.

[0020]

As described above, in the display device according to the first aspect, since the photocatalyst is provided on the display surface, the photocatalyst is activated by the light emitted from the light emitting portion in the display device.
By the action of the photocatalyst, the display surface of the display device is always kept clean and a clear display can be performed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state where a display device is attached to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the display device shown in FIG.

FIG. 3 is a cross-sectional view of a display device according to a second embodiment.

FIG. 4 is a sectional view of a display device according to a third embodiment.

[Explanation of symbols]

 Reference Signs List 10 display device 12 dash panel 20 liquid crystal panel 24 active matrix substrate 26 twisted nematic liquid crystal 28 color filter substrate 30 plane light source 42, 44 polarizing plate 50 photocatalytic layer 70 detection layer

Claims (1)

[Claims] 1. A display device having an active light emitting unit,
A display device comprising a photocatalyst layer formed on a display surface side surface.