JPH05127143A - LCD anti-glare device - Google Patents

Abstract

(57) [Abstract] [Purpose] Prevents or removes fogging caused by frost, fog, humidity, etc. on the surface of liquid crystal panels. [Structure] The transparent substrate 1 is provided outside the polarizing plates 1-2 and 1-6.
-1, 1-7 are arranged to protect the polarizing plate. By energizing one or both of the transparent electrodes 1-9 and 1-10, water vapor and the like adhering to the substrates 1-3 and 1-5 are evaporated to prevent / remove fogging.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antiglare device for controlling the amount of transmitted light in vehicles such as automobiles, trains and airplanes in accordance with the amount of sunlight and the amount of headlights of oncoming vehicles. Such an antiglare device performs antiglare to prevent instantaneous glare on front panels, side mirrors, interior mirrors, etc. of automobiles and motorcycles.

[0002]

2. Description of the Related Art Hitherto, such an antiglare device has not been proposed.

The present invention intends to provide such an antiglare device by utilizing the alignment control of the liquid crystal of the liquid crystal panel.

[0004]

However, when clouding occurs due to frost, fog, humidity, etc. on the substrate holding the liquid crystal of such a liquid crystal panel, the effect of clouding is further superimposed on the antiglare effect and the windshield and the mirror are mirrored. There is an inconvenience such that the scenery cannot be seen at all through.

The object of the present invention is to eliminate such defects and to provide accurate and appropriate antiglare.

[0006]

A liquid crystal antiglare device according to the present invention has a pair of transparent electrodes formed on inner surfaces of a pair of substrates which face each other, and a transparent layer is interposed in a liquid crystal layer enclosed between the substrates. In a liquid crystal antiglare device that performs antiglare by changing the amount of light transmitted through the liquid crystal layer by applying an electric field, a polarizing plate is arranged outside the pair of substrates, and a transparent substrate is further provided outside the polarizing plate. It is characterized in that it is laminated and an energizing means for energizing one or both of the transparent electrodes to heat the transparent electrodes is provided to prevent or remove fogging.

[0007]

EXAMPLE FIG. 1 shows a windshield of an automobile or the like on the entire surface,
FIG. 2 partially shows an example in which the antiglare device according to the present invention is implemented. In FIG. 1, 1-3 and 1-5 are substrates, usually inorganic glass, having transparent electrodes 1-9 and 1-10 made of ITO, indium oxide, tin oxide, etc., and holding a liquid crystal 1-4. is doing. 1-2 and 1-6 are polarizing plate pairs used when the liquid crystal 1-4 is a twisted nematic (hereinafter abbreviated as TN) liquid crystal. 1-1 and 1-7 are transparent substrates such as inorganic glass that protect the polarizing plates 1-2 and 1-6. Reference numeral 1-8 is a spacer provided on the outer periphery that seals the space of the held liquid crystal 1-4. Reference numeral 1-11 is a powder made of an insulating material for uniformly maintaining the space thickness formed by the inorganic glass substrates 1-3 and 1-5 so that the liquid crystal 1-4 has a uniform thickness. As the powder 1-11, glass fiber, alumina, glass beads or the like is used.

In this embodiment, one or both of the transparent electrodes 1-9 and 1-10, which excite the electric field effect in the liquid crystal to perform the antiglare effect, are energized to form the substrates 1-3 and 1
-5 One or both of the temperatures is raised to evaporate water vapor and the like adhering to the substrate to prevent fogging or remove fogging. In this case, the energization for clouding prevention and removal may be performed by superposing the energization signal on the signal energized to the transparent electrode for antiglare. For example, the transparent electrodes 1 facing each other through the liquid crystal 1-4
By superimposing the same voltage signal on both -9 and 1-10, the anti-glare signal is not impaired, and the predetermined anti-glare effect can be achieved and at the same time the heater action can be performed. In addition, the resistance value of the transparent electrode 1-3 or 1-5 is reduced, and a current is passed from one end to the other end of the electrode to generate heat, and at the same time, the voltage between the transparent electrodes 1-3 and 1-5 is controlled, You may perform an anti-glare effect. When an electric field is applied between the electrodes 1-9 and 1-10 of the antiglare device configured as described above, the amount of transmitted light can be controlled by the electric field proportional to the strength of the electric field by the light amount detection device according to the glare. Although the light amount detection device and the light amount control circuit are not shown, they do not change the gist of the present invention. The light amount detecting device may change and use the resistance value according to the light amount of, for example, a phototransistor or cds, and the setting place may be a place where there is no problem in appearance in the viewing direction. The detection signal of the light amount detecting device is guided to the light amount control circuit and drives the antiglare device according to the present invention by an AC electric field which is substantially proportional to the light amount. It enables an instantaneous and wide-range anti-glare device.

A polarizing plate is required when the liquid crystal 1-4 is TN, but a polarizing plate is not required when a known guest-host (hereinafter abbreviated as GH) is used. When a polarizing plate is used, it is inconvenient because the field of view becomes dark at night, etc.
If the polarizing plate is not used, the field of view can be made brighter when it is not dazzling.

The entire liquid crystal cell may have a curvature as shown.

FIG. 2 is a sectional view of an example partially applied in another embodiment of the antiglare device according to the present invention. 2 as in FIG.
-3 and 2-5 are glass, 2-9 and 2-10 are electrodes, 2-
8 is a spacer, 2-11 is inorganic powder, 2-2 and 2-6 are polarizing plates, 2-1 and 2-7 are polarizing plate protective glasses, 2-4
Is composed of liquid crystal. The operation principle in the case of preventing fogging is the same as that described in FIG. When GH is used, a polarizing plate is not required, so an antiglare device is obtained by removing unnecessary components from FIGS. 1 and 2.

FIG. 3 shows an example in which the antiglare device according to the present invention is partially (shaded) provided on a windshield 3-1 of an automobile.

It is intended to prevent the sunlight from directly entering the eyes of the driver or the like and erroneously driving.

[0014]

As described above, according to the liquid crystal antiglare device of the present invention, it is possible to prevent or eliminate the occurrence of fogging on the liquid crystal panel for antiglare due to humidity, and prevent excessive antiglare. it can. Furthermore, since one or both of the transparent electrodes that perform the antiglare action generate heat, it is not necessary to separately provide an electrode for heat generation. Therefore, the liquid crystal panel can be made thinner.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an antiglare device according to the present invention when it is applied to the entire windshield of an automobile or the like.

FIG. 2 is a cross-sectional view of the antiglare device according to the present invention when implemented on a part of a windshield of an automobile or the like.

FIG. 3 is a view showing an example in which an antiglare device according to the present invention is partially (shaded) provided on a windshield of an automobile.

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[Procedure amendment]

[Submission date] May 27, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

[0014]

As described above, according to the liquid crystal antiglare device of the present invention, it is possible to prevent or eliminate the occurrence of fogging on the liquid crystal panel for antiglare due to humidity, and prevent excessive antiglare. it can. Especially, the transparent substrate is laminated on the outside of the polarizing plate.
And protect the polarizing plate from the external environment. Thus outdoors
Use, for example on the windshield
It Furthermore, since one or both of the transparent electrodes that perform the antiglare action generate heat, it is not necessary to separately provide an electrode for heat generation. Therefore, the liquid crystal panel can be made thinner.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] Explanation of code

[Correction method] Added

[Correction content]

[Explanation of Codes] 1-1, 1-7 Transparent substrate 1-2, 1-6 Polarizing plate 1-8 Spacer 1-4 Liquid crystal 1-3, 1-5 Substrate 1-9, 1-10 Transparent electrode

Claims (1)

[Claims] 1. A pair of transparent electrodes are formed on opposing inner surfaces of a pair of substrates, and a liquid crystal layer sealed between the substrates is transmitted through the liquid crystal layers by applying an electric field through the transparent electrodes. In a liquid crystal antiglare device that changes the amount of light to perform antiglare, a polarizing plate is arranged outside the pair of substrates, and a transparent substrate is further laminated outside the polarizing plates, and one or both of the transparent electrodes are energized. A liquid crystal antiglare device, characterized in that an energizing means for heating the transparent electrode is provided to prevent or remove fogging.