KR100354256B1 - Color change LCD as temperature change - Google Patents

Abstract

Purpose: Attaching another liquid crystal panel into which the cholesteric liquid crystal is changed in color depending on the temperature on the back of a conventional liquid crystal display device. Provided is an element.

Configuration: A driving liquid crystal display device comprising: an upper and lower substrates each having a transparent electrode and an alignment layer formed on opposite surfaces thereof, and a liquid crystal is injected into a space defined by the substrate and sealant to display desired information; It is composed of a configuration including a non-driven liquid crystal display device injecting a cholesteric liquid crystal material which is not driven but changes color depending on temperature.

Effect: The background color of the liquid crystal display device can be changed according to the temperature, and a function can be arbitrarily changed by changing a color of a logo, a picture, a character, etc. by patterning a predetermined heating device, which requires special visibility. There is an effect that can be used in various fields, such as advertising.

Description

Color change LCD as temperature change}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device whose color changes with temperature. More specifically, a panel containing a cholesteric liquid crystal having a color change depending on temperature is attached to a rear surface of a conventional liquid crystal display device, thereby providing a background color or pattern. The present invention relates to a liquid crystal display device in which a color changes according to a temperature at which a color of color may be arbitrarily implemented.

A liquid crystal display device is a kind of display device, and the most widely used display device is a cathode ray tube (CRT). However, CRT is not easy to planarize, and as the display area is widened, the weight becomes heavier and the volume becomes considerably larger. Therefore, recently, flat panel display devices are being developed to solve such shortcomings of the CRT and lead the next generation display industry.

There are various types of flat panel display devices. Researchers and investors have studied liquid crystal display (LCD), plastic LCD (PLCD), plasma display panel (PDP) and field emission device (FED). Actively in progress

Among the flat panel display devices, the liquid crystal display device is the most widely applied display device, and can be driven at low power by adopting a battery power source, and has various advantages such as small displays, portable phones, PDAs, notebook computers, etc. It is also being used for large screen products.

The liquid crystal display device uses the characteristics of the liquid crystal having the characteristics of changing the molecular arrangement of the liquid crystal along the direction of the electric field when a voltage is applied while having regular molecular arrangements and optical anisotropy such as crystals of a solid together with liquid flowability. , Refers to a device that displays characters or pictures.

The liquid crystals used in the liquid crystal display device may be classified into nematic liquid crystals, cholesteric liquid crystals, smectic liquid crystals, and discotic liquid crystals according to molecular shape and arrangement, and according to electro-optical characteristics, TN (Twisted Nematic) and STN ( Super Twisted Nematic (GH), Guest-Host (GH), etc. Currently, nematic liquid crystals are the most widely used liquid crystal display devices for implementing a screen by applying a voltage.

Among the cholesteric liquid crystals, there are liquid crystals having a characteristic of changing color depending on temperature. The cholesteric liquid crystal for temperature transfer has been used only in limited fields such as thermometers or general thermometers that display color according to the temperature of a person using a temperature sensitive feature.

Fig. 3 schematically shows a cross section of a conventional liquid crystal display element employing nematic liquid crystals.

As shown in the drawings, the conventional liquid crystal display device 2 has a transparent electrode (ITO) 6 (6 ') on an opposite surface facing the upper substrate 4 and the lower substrate 4' employing a glass or plastic film. After the alignment layers 8 and 8 'are formed in turn, the space between the upper substrate 2 and the lower substrate 4 is provided with a sealant 10 to provide a space for the liquid crystal to be injected, and the upper and lower substrates 2 and 4 are formed. Bond it. After that, the nematic liquid crystal is injected and sealed, and then the polarizing plates 12 and 12 ′ are attached to the upper substrate 2 and the lower substrate 4.

Since the liquid crystal display device having the above-described structure does not have a color filter, two colors of the text or picture display unit and the background color are converted and displayed.

Since the display color is limited to one or two, basic recognition can be provided, but it is difficult to expect advertisement effects to attract a lot of attention due to color change or movement.

The present invention devised to solve the above-described problems of the prior art can be obtained by attaching a panel containing a cholesteric liquid crystal that changes color depending on temperature on the rear of the conventional liquid crystal display device to obtain a color display function and color change effect It is an object of the present invention to provide a liquid crystal display device whose color changes with temperature.

To this end, the liquid crystal display device of the present invention is a liquid crystal display device in which a liquid crystal is injected and sealed between upper and lower substrates on which transparent electrodes are patterned, and then a voltage is applied to display the first substrate and the transparent electrodes. And a cholesteric liquid crystal panel in which a cholesteric liquid crystal is injected into a space defined by the sealant and adhered between a second substrate and the first substrate and the second substrate with a sealant. It consists of a structure attached to the back of one liquid crystal display element.

It is preferable that the upper plate and the lower plate adopt a glass or plastic film.

The cholesteric liquid crystal uses a temperature transfer cholesteric liquid crystal whose color changes with temperature.

The liquid crystal display device manufactured by the above-described configuration can obtain the effect of realizing the color by changing the background color according to the ambient temperature, and by heating a certain portion by applying a voltage to the transparent electrode patterned on the cholesteric liquid crystal panel For example, the predetermined shape is displayed in the background when desired so that the advertisement effect and visibility are excellent.

1 is a cross-sectional view showing an embodiment of a liquid crystal display device that changes color depending on the temperature according to the present invention.

2 is a cross-sectional view showing another embodiment of a liquid crystal display device whose color is changed according to the temperature according to the present invention.

3 is a cross-sectional view showing a conventional liquid crystal display device.

** Description of the symbols for the main parts of the drawings **

2: liquid crystal display element 4,4 ': substrate

6,6 ': transparent electrode 8,8': alignment layer

10: sealant 12,12 ': polarizer

20,20 ': low power consumption LCD 30: cholesteric liquid crystal panel

31: cholesteric liquid crystal 32, 40: first substrate

34,40 ': second substrate 42,44: heat generating means

EMBODIMENT OF THE INVENTION The structure of this invention is demonstrated in detail based on attached drawing. For reference, prior to the description of the present invention will be referred to the same reference numerals as for the parts corresponding to the conventional drawings.

Example 1

1 is a view schematically showing an embodiment of a liquid crystal display device whose color changes according to the temperature according to the present invention.

Referring to the drawings, the structure of the liquid crystal display device 20 that changes color according to the temperature according to the present invention has a configuration in which the cholesteric liquid crystal layer 30 is disposed on the rear surface of the conventional liquid crystal display device 2.

That is, the upper substrate 4 and the lower substrate 4 'are opposed to each other with a predetermined space. The upper and lower substrates 4 and 4' are made of glass or plastic. On the opposite side of the upper substrate 4 and the lower substrate 4 ', transparent electrodes 6, 6' are patterned and polyimide alignment layers 8, 8 over the transparent electrodes 6, 6 '. ') Is coated.

The upper substrate 4 and the lower substrate 4 ′ having the above-described configuration have a space in which liquid crystals are injected while simultaneously dispersing spacers and printing the sealant 10 to bond the upper and lower substrates to maintain a constant gap. To prepare.

The liquid crystal is injected in a vacuum state into the space defined by the sealant 10, and after the end is actually sealed, the polarizing plates 12 and 12 ′ are attached to the upper substrate 4 and the lower substrate 4 ′, respectively. The configuration is the same as that of the conventional liquid crystal display device.

The cholesteric liquid crystal panel 30 is attached to the bottom surface of the polarizing plate 12 ′ attached to the lower substrate 4. The configuration of the cholesteric liquid crystal panel 30 will be described with reference to FIG. 1. Is as follows.

The cholesteric liquid crystal panel 30 is a configuration in which the cholesteric liquid crystal 31 is contained between the first substrate 32 and the second substrate 34 so that liquid crystal does not leak out. The first and second substrates 32 and 34 are made of glass or plastic, and the first and second substrates 32 and 34 are patterned with segment electrodes for displaying letters or pictures. Not.

The first and second substrates 32 and 34 have an alignment film (not shown) formed on a simple glass or plastic film, and provide a liquid crystal injection space with a spacer and a sealant 10, and a cholesteric liquid crystal in the liquid crystal injection space. Inject (31).

According to an exemplary embodiment of the present invention, the color of the liquid crystal display is changed in color according to the temperature. As described above, a nematic liquid crystal or smectic liquid crystal is injected to apply a voltage to display a screen on the back of the liquid crystal display device for displaying a screen. The liquid crystal panel 30 is attached.

The cholesteric liquid crystal 31 does not refer to a general cholesteric liquid crystal but employs a cholesteric liquid crystal 31 in which the color of the liquid crystal changes with temperature change.

The liquid crystal display device formed by the above-described configuration implements color according to the ambient temperature, so that the color is not only given to the background of the character or picture display unit but also the color changes as the temperature changes. The cholesteric liquid crystal panel is mounted on a device directly in contact with the body, and thus, the cholesteric liquid crystal panel is in contact with the body.

Example 2

2 schematically shows another embodiment 20 'of a liquid crystal display device whose color changes according to the temperature according to the present invention.

As shown in the figure, the configuration of the liquid crystal display device to which the cholesteric liquid crystal panel 30 is attached is the same as the embodiment of the present invention. The cholesteric liquid crystal panel 30 attached to the rear surface of the liquid crystal display device has a difference in construction from one embodiment.

An alignment film is formed only on the first substrate 40, and heat generating means 42 and 44 are formed on the second substrate 40 'as well as an insulating film (not shown) and an alignment film (not shown). When the voltage is applied to the heating means (42, 44) is applied to the heat generating means (42) 44, the heat generated by the heat generating means 42, 44 patterned portion of the liquid crystal 31 The temperature rises. The color of the cholesteric liquid crystal 31 is changed by the elevated temperature, and the user can produce a color display effect on letters, logos, and pictures by the heating means 42 and 44 of the second substrate 40 '. You can do that.

The heat generating means 42 and 44 are used by patterning transparent electrodes and other electrodes.

In addition, by adjusting the amount of heat generated by applying a voltage to the heating means (42, 44), it is also possible to vary the color of the cholesteric liquid crystal 31 implemented by the temperature to be able to display a variety of colors arbitrarily .

The present invention embodied by the above embodiments overcomes the disadvantages of the conventional liquid crystal display device in which the contrast is changed by the application of voltage, and provides a liquid crystal display device capable of converting colors according to temperature, thereby providing various screens. It can be used in a variety of fields that require characteristic visibility, such as advertising or logo by providing a and improve the visibility of the screen.

The background color of the liquid crystal display device may be changed according to the ambient temperature, and a function of changing a color of a logo, a picture, a character, etc. by patterning a predetermined heat generating device may be included, and thus requires special visibility. There is an effect that can be used in a variety of fields.

Claims (7)

A driving liquid crystal display device having upper and lower substrates each having a transparent electrode and an alignment layer formed on opposite surfaces thereof, wherein liquid crystal is injected into a space defined by the substrate and sealant and displays desired information; The cholesteric liquid crystal material, which is not driven but changes color depending on temperature, is injected into the internal space formed by the first substrate, the second substrate, and the sealant, and a voltage may be applied to the inner surface of the second substrate. And a non-driving liquid crystal display device capable of arbitrarily changing colors by providing a heat generating means formed of a transparent electrode. delete The liquid crystal display of claim 1, wherein the first substrate and the second substrate are made of glass or plastic. The liquid crystal display device of claim 1, wherein the cholesteric liquid crystal is a temperature-transfer liquid crystal whose color changes with temperature. delete delete The liquid crystal display of claim 1, wherein the first substrate is a lower substrate of the driving liquid crystal display.