KR101208515B1 - Liquid crystal display device with solar cell - Google Patents

Abstract

The present invention relates to a liquid crystal display device (Liquid Crystal Display device), the upper substrate, the lower substrate, the backlight below the lower substrate, and formed between the lower substrate and the upper substrate, the lower substrate and Provided is a solar cell embedded liquid crystal display device including a solar cell unit capable of receiving light flowing through the upper substrate. According to the present invention, since it is possible to produce power using backlight light at night as well as at daytime with strong solar light, it can be supplied to a terminal to which a liquid crystal display device with a built-in solar cell according to the present invention is connected. When applied to a mobile terminal such as, for example, a mobile phone having an operating characteristic has a very advantageous advantage in terms of power consumption reduction.

LCD, LCD, Cell, Solar Cell

Description

Liquid crystal display device with solar cell

1 is a cross-sectional view showing a schematic structure of a conventional liquid crystal display device.

2 is a schematic cross-sectional view of a liquid crystal display device with a solar cell according to the present invention.

3 is a circuit diagram illustrating a configuration in which a liquid crystal display device having a built-in cell is mounted on an arbitrary terminal and an operation principle thereof according to the first embodiment of the present invention.

FIG. 4 is a circuit diagram illustrating a configuration in which a liquid crystal display device having a built-in cell is mounted on an arbitrary terminal and an operation principle thereof according to the second embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

1, 3: liquid crystal display 10: lower substrate

13: pixel electrode 15: thin film transistor

30: upper substrate 70: backlight

90: cell unit 91: first solar cell

95: second cell 200: switch for selecting a cell

300: terminal battery 400: terminal body

450: terminal control unit 500: charge blocking switch

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device which further reduces power consumption by using a solar cell.

A liquid crystal display device has a regular molecular arrangement such as a liquid crystal along with the liquidity of the liquid, and has an optical anisotropy, and when the voltage is applied, the liquid crystal display changes the molecular arrangement according to the direction of the electric field. It is a device for flat panel display to implement.

A conventional liquid crystal display device will be described with reference to FIG. 1. 1 is a cross-sectional view showing a schematic structure of a conventional liquid crystal display device.

As shown in FIG. 1, liquid crystal is injected into a liquid crystal display device 1 by a spacer (not shown) for maintaining a cell gap between a transparent lower substrate 10 and an upper substrate 30. They are provided to face each other at a predetermined interval, and the liquid crystal 50 is injected between the lower substrate 10 and the upper substrate 30.

In addition, a plurality of pixel electrodes 13 are formed on an inner surface of the lower substrate 10, and each of the pixel electrodes 13 is formed with a thin film transistor 15 functioning as a so-called switching element. ), An alignment film (not shown) is formed. Here, the drain electrode (not shown) of the thin film transistor is a portion connected to the pixel electrode 13. A backlight 70, which serves as a light source of the liquid crystal display, is disposed under the lower substrate 10.

Meanwhile, a transparent common electrode 33 is formed on an inner surface of the upper substrate 30 to face the plurality of pixel electrodes 10, and an alignment layer (not shown) is formed on the common electrode 33. .

A driving voltage is applied between the pixel electrode 13 and the common electrode 33 to adjust the arrangement direction of the liquid crystal 50 so that the light of the backlight 70 is selectively transmitted to each pixel so that the liquid crystal display device ( 1) acts as a display.

In recent years, the liquid crystal display device 1 is widely used as a display device in various terminals such as a mobile terminal. Since the mobile terminal operates for a predetermined time with limited power, there is an urgent need for the minimum power consumption of the liquid crystal display device mounted thereon.

Accordingly, the present invention is proposed to solve the above-described problems, the power supply device for a terminal equipped with a liquid crystal display device, which is basically a power consumption device to be a power production device in some cases by using a cell It is an object of the present invention to provide a liquid crystal display device with a built-in cell that can operate as a solar cell.

In order to achieve the above object, the present invention is formed between an upper substrate, a lower substrate, a backlight under the lower substrate, and between the lower substrate and the upper substrate to receive light flowing through the lower substrate and the upper substrate. Provided is a built-in liquid crystal display device including a solar cell unit.

In addition, to achieve the above object, the present invention, in the liquid crystal display device with a built-in cell that can be mounted on any terminal, when the voltage of the battery of the terminal is a predetermined voltage or more electrical with the battery of the solar cell It provides a solar cell built-in liquid crystal display, characterized in that the connection is blocked.

In the present invention, as can be seen from the above, it is intended to achieve the above object by embedding a solar cell (Solar Cell) in the liquid crystal display device. Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention that can specifically achieve the above object will be described. The same components as the prior art are given the same names and the same reference numerals for convenience of description, and detailed description thereof will be omitted.

First, with reference to the drawings looks at the configuration of the liquid crystal display device (3) embedded in the cell according to the present invention. 2 is a schematic cross-sectional view of a liquid crystal display device with a solar cell according to the present invention.

As shown in FIG. 2, a solar cell unit 90 is formed between the lower substrate 10 and the upper substrate 30 of the liquid crystal display device 3 according to the present invention.

The solar cell unit 90 includes a first cell 91, a first electrode layer 93, a second cell 95, a second electrode layer 97, and a common electrode layer 99. .

The first solar cell 91 and the second solar cell 95 are P layers (P type semiconductors) 91-1 and 95-1 and N layers (N type semiconductors) 91-2 and 95-2, respectively. It is preferable that the PN junction diode converting light into a current. When light is applied to the PN junction surface of the first solar cell 91 or the second solar cell 95, free electrons are collected in the N-type semiconductor and holes are collected in the P-type semiconductor. The free electrons and the holes generate a current to the load connected to the solar cell unit, so that the solar cell unit can serve as a kind of power source. This will be described later in detail later.

Preferably, two (or three or more) solar cells are used for the solar cell unit 90, that is, the first solar cell 91 and the second solar cell 95 are introduced through the upper substrate. In order to efficiently receive light (for example, sunlight) and light flowing through the lower substrate (for example, light of the backlight 70) and convert the light into a power source. The first solar cell 91 serves to receive light from the lower substrate 10, and the second solar cell 95 serves to receive light from the upper substrate 30.

The first solar cell 91 and the second solar cell 95 have the common electrode layer 99 interposed therebetween, and the P layer 91-1 and the second solar cell 95 of the first solar cell 91 are disposed therebetween. It is preferable that the P layers 95-1 be bonded to each other so as to face each other. Accordingly, the N layer 91-2 of the first solar cell 91 and the N layer 95-2 of the second solar cell 95 may face the lower substrate 10 and the upper substrate 30, respectively. It is preferable to arrange. This is because the efficiency of the solar cell is generally higher when the solar cell N layer faces the light source than when the P layer of the cell faces the light source.

The first electrode layer 93 is formed on the N layer 91-2 of the first solar cell 91, and the second electrode layer 97 is formed on the N layer 95-2 of the second solar cell 95. It is preferable that this be formed.

The configuration and operation principle of the solar cell-embedded liquid crystal display device in any terminal will be described in detail in the first and second embodiments.

1st Example

3 is a circuit diagram illustrating a configuration in which a liquid crystal display device having a built-in cell is mounted on an arbitrary terminal and an operation principle thereof according to the first embodiment of the present invention. In FIG. 3, only the solar cell unit 90 of the solar cell-embedded liquid crystal display 3 according to the present invention is illustrated for simplicity of description.

The solar cell unit 90 is connected to the terminal as shown in FIG. That is, one of the first electrode layer 93 and the second electrode layer 97 is connected to the first electrode of the terminal battery 300 through the cell selection switch 200, and the common electrode layer 99 is connected to the terminal. It is connected to the second electrode of the battery 400.

The solar cell selection switch 200 allows the terminal battery 300 to select whether the current from the first solar cell 91 or the second solar cell 95 is to be supplied. For example, since the backlight for the cell selection switch 200 will be brighter than the external light at night, the first electrode layer 93 of the first solar cell 91 that receives the backlight light and generates a current may be the same. The second electrode layer of the second solar cell 95 to be connected to the first electrode of the terminal battery 300, and the external light (for example, sunlight) will be brighter than the backlight light during the day to receive the external light to generate a current 97 is connected to the first electrode of the terminal battery 300.

The control of the cell selection switch 200 according to the comparison of the brightness of the external light and the backlight light may be performed in various ways, but may be simply implemented as the CdS cell 250. That is, since the brightness of the backlight is always constant, the CdS cell 250 senses the brightness of the external light and outputs a predetermined signal when the external light is brighter than the predetermined brightness (that is, the brightness of the backlight) and outputs the predetermined signal. Is to be used as a control signal of the cell selection switch 200.

Thus, the current generated from the first or second solar cell 91 or the second solar cell 95 capable of receiving the brighter light of the external light and the backlight light may be charged in the terminal battery. Therefore, the terminal battery can be charged using the backlight light not only during the day but also at night.

Second Example

In the case of the first embodiment described above, when the terminal battery 300 is already sufficiently charged, the voltages between the first electrode and the second electrode of the terminal battery 300 are connected to the terminal battery 300. The voltage between the first electrode layer and the common electrode layer according to the first cell 91 may be greater than the voltage between the second electrode layer and the common electrode layer according to the second solar cell 95. In such a case, there is a high possibility that the solar cell is damaged due to a reverse current flowing through the solar cell. Accordingly, the second embodiment of the present invention relates to a configuration in which the solar cell liquid crystal display device 3 is mounted on an arbitrary terminal and an operation principle thereof so as to solve the problems of the first embodiment.

FIG. 4 is a circuit diagram illustrating a configuration in which a liquid crystal display device having a built-in cell is mounted on an arbitrary terminal and an operation principle thereof according to the second embodiment of the present invention. In FIG. 4, only the solar cell unit 90 of the solar cell-embedded liquid crystal display 3 according to the present invention is illustrated for simplicity of description. In the description of the configuration of FIG. 4 according to the second embodiment, the same parts as the configuration of FIG. 3 according to the first embodiment will be omitted for simplicity.

As shown in FIG. 4, the charge blocking switch 500 is configured between the cell selection switch 200 and the terminal battery 300. (The charging cutoff switch 500 may be configured between the common electrode layer 99 and the terminal battery 300.) The charging cutoff switch 500 is a control unit of the terminal main body 400. Under control of 450.

In other words, the terminal controller 450 monitors the charging voltage of the terminal battery 300. As a result of the monitoring, when the charging voltage of the terminal battery 300 is equal to or higher than a predetermined voltage (that is, a threshold voltage for generating a reverse current in the solar cell), a control signal is sent to the charging cutoff switch 500 so that the charging cutoff switch 500 ) To open.

Then, since the solar cell unit 90 and the terminal battery 300 are electrically disconnected from each other, when the terminal battery 300 is overcharged, the first cell 91 or the second cell 95 This prevents the possibility of generating reverse current at the source.

It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. For example, in the above description, a configuration in which the terminal battery can be selectively charged using any one of the first or second solar cells has been described, but those skilled in the art will appreciate the configuration described herein. From the first solar cell and the second solar cell can be easily modified to a configuration that can be charged to the terminal battery by using at the same time.

Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

Referring to the effects of the cell embedded liquid crystal display according to the present invention described above are as follows.

As described above, according to the present invention, it is possible to produce power using backlight light at night as well as at daytime when the sunlight is strong, and supply it to a terminal to which the liquid crystal display with a built-in cell according to the present invention is connected. Therefore, in particular, when applied to a mobile terminal such as a mobile phone having a characteristic of operating while moving for a predetermined time with a limited power has a very advantageous advantage in terms of power consumption reduction.

Claims (8)

Upper Board, Lower Board, A backlight under the lower substrate, An N-layer facing the lower substrate, a first electrode layer formed on the N-layer, and a PN-type first solar cell receiving light flowing through the lower substrate; The P layer is opposite to the P layer of the first solar cell, the N layer faces the upper substrate, the second electrode layer is formed on the N layer, and has a PN type to receive light flowing through the upper substrate. A second cell, and A cell-embedded liquid crystal display device including a common electrode layer formed between the P layers of the first and second cells;  A battery in which a first electrode is connected to any one of the first electrode layer and the second electrode layer, and a second electrode is connected to the common electrode layer; And And a controller configured to control the first electrode layer and the second electrode layer to not be connected to the first electrode of the battery, when the voltage of the battery is equal to or greater than a preset voltage. . delete delete delete The method of claim 1, The controller may control the second electrode layer to be connected to the first electrode of the battery if the intensity of the light flowing into the second solar cell is greater than the intensity of the light flowing into the first solar cell. Otherwise, the controller may control the first electrode layer. And a control unit connected to the first electrode of the battery. delete The method of claim 1, The control unit includes a liquid crystal display device with a built-in cell, characterized in that if the voltage of the battery is greater than the predetermined voltage, the common electrode layer is controlled so as not to be connected to the second electrode of the battery. delete

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