KR200457688Y1 - Key pad assembly for cellular phone having PDLC film - Google Patents

Abstract

Dome sheet under the backlight layer, back light layer, dome switch installed under the dome sheet, the circuit board having a part opened and closed by the dome switch, placed on the backlight layer, and entered letters, numbers or Disclosed is a keypad assembly for a cellular phone, comprising a polymer dispersed liquid crystal (PDLC) panel in which a symbol can be displayed. The PDLC panel includes at least a substrate, a transparent conductive layer pattern formed on the substrate, and a PDLC film layer formed on the transparent conductive layer pattern.
According to the present invention, symbols, letters, and number groups can be distinguished and displayed for each mode, so that symbols, letters, and numbers to be input can be found more quickly and easily, and symbols, characters that can be displayed by key buttons at specific positions In addition, the keypad arrangement can be changed so that the numbers are different, so that the user's convenience can be enhanced by utilizing the button more flexibly than the keypad of the existing mobile phone.

Description

Keypad assembly for cellular phone having PDLC film

The present invention relates to a structure of a mobile phone, and more particularly to a structure of a keypad assembly of the mobile phone.

As mobile phones become smaller and more versatile, various restrictions are imposed on the demands of mobile phones. An important function of a mobile phone is a keypad assembly, or a keyboard type input device. The keypad may be called a keypad by limiting the upper keyboard layer exposed to the outside of the keypad assembly. The keypad assembly can input various characters through a combination of various buttons in the keyboard, in addition to simply inputting a number, that is, a number to be called in a recent mobile phone. It can also serve as a button to select.

In particular, smart phones, which are telephones and can serve as terminals and computers on a network such as the Internet, can display letters on the screen itself in the form of a touch screen, but the characters can be input using the keypad assembly while viewing the screen. There is still a need. In many cases, the keypad is extended to increase the number of key buttons, similar to a computer keyboard.

However, mobile phones are still difficult to install many buttons such as a keyboard of a computer even when the keypad is expanded due to the limitation of the portable. Therefore, in order to act as a keyboard of a computer, a combination of key buttons becomes complicated and difficult to use, such as pressing the same key button two or more times in succession or combining different key buttons. In addition, the number of letters, numbers, and symbols associated with a single key button increases, and in order to display all of them on the keyboard, the keyboard display becomes complicated and unfamiliar letters or symbols become difficult to find.

On the other hand, in order to cover the limit of the number of key buttons in the existing mobile phones, the keypad mode is set to a plurality of numbers, Korean, English, symbols, etc., and the numbers, letters, or symbols that can be expressed by the key buttons at specific positions for each mode. Different characters can be represented differently. However, certain keybuttons could not be used to enter other numbers, letters and symbols as needed. In other words, in order to represent one specific letter, number, or symbol, a mode must be specified, and the number of keybuttons pressed in that mode must be determined singularly. The specific letter, number, or symbol can be implemented by pressing another key button. There was no.

It is an object of the present invention to provide a keypad assembly for a cellular phone that can quickly and quickly recognize and easily input various numbers, symbols, and characters through the keypad while maintaining a limited number of key buttons on the keypad of the cellular phone. .

The object of the present invention is to provide a keypad assembly for a cellular phone that can flexibly utilize the key button of the keypad of the existing cellular phone.

The keypad assembly for mobile phones according to the present invention for achieving the above object has a dome sheet under the backlight layer, a back light layer and a dome switch installed under the dome sheet, and having a portion opened and closed by the dome switch. It has a PDLC (polymer dispersed liquid crystal) panel which is placed on a circuit board and a backlight layer and can display input letters, numbers or symbols (hereinafter abbreviated as 'letters'). Characterized in that made.

In the present invention, the PDLC panel includes at least a substrate, a transparent conductive layer pattern formed on the substrate, and a PDLC film layer formed on the transparent conductive layer pattern (where 'up' includes a wide overlapping position). The PDLC panel may be of a type in which a PDLC film layer is interposed between the transparent conductive layer or the substrate on which the transparent conductive layer pattern is formed.

In the present invention, the transparent conductive layer pattern may be a pixel pattern capable of displaying an active matrix pixel.

In the present invention, the transparent conductive layer pattern may be a pattern that directly displays characters to be input. In this case, the plurality of transparent conductive layer patterns corresponding to one dome switch region may be plural, and the plurality of transparent conductive layer patterns may be divided or displayed according to modes.

In the present invention, a PDLC driving driver IC may be used to apply a voltage to the transparent conductive layer pattern, and a backlight driving driver IC may be used to operate the backlight layer. These ICs can be integrally formed, and a PDLC driving driver IC for driving a transparent conductive layer pattern is installed on a printed circuit board located under a dome sheet or used to display a display screen on a display window of a mobile phone. It may be formed integrally with the driving driver IC.

According to the present invention, the PDLC screen can be used to represent symbols, letters, and numbers that can be input by the keypad. , Numbers can be prevented from appearing on the keypad screen, so you can quickly and easily find and enter the symbols, letters, and numbers you want to enter.

In addition, if the mode is added by operating the keypad driver IC, the PDLC screen can be input in any form, either horizontally or vertically. The keypad arrangement can be varied to vary.

As a result, the present invention can increase the user's convenience by utilizing the button more flexibly than the keypad of the conventional mobile phone.

1 is a cross-sectional view showing a state in which a keypad assembly formed according to an embodiment of the present invention is coupled with a mobile phone upper case;
Figure 2 is a cross-sectional view showing a side cross-sectional view of the PDLC panel used in one embodiment of the present invention;
3 to 6 are conceptual views illustrating a set of letters, numbers, or symbols displayed on a screen of a PDLC panel forming a keypad according to an embodiment of the present invention for each specific mode.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1 is a cross-sectional view illustrating a state in which a keypad assembly formed according to an embodiment of the present invention is mounted together with a mobile phone upper case.

The PDLC panel 40 is installed in place of the conventional keypad engraved with numbers on its own through the window of the upper case 50 of the cellular phone, and the backlight layer 30 is installed under the PDLC panel 40. . Below the backlight layer 30 is a dome sheet 20 formed by installing a dome switch 23 on the base sheet 21 for each key button region of the keypad. Below the dome sheet 20 is a printed circuit board 10 including a circuit that is opened and closed by a dome switch 23. The dome sheet 20 is coupled to the printed circuit board 10 through the adhesive layer 22 on the bottom surface. The periphery of the dome switch 23 is connected to one contact 11 of the printed circuit board. The dome switch 23 is deformed when the center portion of the dome switch 23 in the specific button area is pressed. At this time, the center portion of the dome switch 23 is in contact with the other contact 13 of the printed circuit board, the dome switch serves to electrically connect one contact 11 and the other contact (13). Actuator 24 serves to more easily deform the dome switch 23 of the corresponding key button area when the key button area of the keypad is pressed.

Among these, the layer structure of the backlight layer 30, the dome sheet 20, and the printed circuit board 10 is already found in the existing keypad assembly. The backlight layer 30 may use a light guide plate film that receives light from the LED lamp 15 at the side and emits light toward the PDLC panel 40 serving as a keypad in the keypad button region. Of course, the organic EL surface light emitting layer, which is a surface light source that emits light directly without using a separate light guide plate, may be used as the backlight layer. In this case, the organic EL surface light emitting layer simply acts as a surface light emitting layer without a pixel configuration, and emits monochromatic light other than white light according to its material property, so that preferred color light can be selected.

The dome sheet 20 includes a dome switch 23, which is a hemispherical convex metal structure, installed in each button region of the base sheet 21. The dome switch must be durable, so it is suitable to consist of a cube with a small solid angle rather than a hemisphere. If the thickness of the dome switch is too thick, it will not be easily deformed, and it will be difficult to act as a switch. If it is too thin, it will be easily damaged.

In the present invention, the PDLC panel 40 corresponds to a conventional keypad, that is, keypad keypad. Unlike conventional keypad keyboards that form holes in opaque synthetic resin panels or fill the hole portions with transparent resin to display characters, and the characters are easily seen by the backlight, the PDLC panel 40 ) To express characters and the like. That is, in the PDLC panel 40, there is no expression such as letters due to the contrast between holes, transparent resins, and opaque resins, and voltages are applied to the transparent conductive film pattern of the PDLC panel to vary the light transmittance of the polymer dispersed liquid crystal film. Will be expressed.

In order to express characters and the like through the PDLC panel, a voltage must be applied to the PDLC film of the PDLC panel. At least one side of the PDLC film must be provided with a conductive pattern for voltage application. When the conductive pattern for voltage application is provided only on one side of the PDLC film, both opposing electrodes for voltage application may be formed on one side of the PDLC film.

2 is a cross-sectional view showing an embodiment of a PDLC panel. In order to form such a panel, first, a transparent conductive film such as ITO is stacked and patterned on the lower substrate 41 to form a transparent conductive film pattern 43 such as letters, symbols, and numbers. The PDLC layer 45 is stacked on the lower substrate 41 on which the transparent conductive film pattern 43 is formed. The PDLC layer 45 may be prepared by various known methods, such as being stacked in a dissolved or dispersed state in a solvent and leaving only a polymer dispersed liquid crystal layer (PDLC layer) through solvent drying or curing. On the polymer dispersed liquid crystal layer, the upper substrate 49 having the transparent conductive film 47 laminated on the entire surface is covered so that the transparent conductive film 47 contacts the polymer dispersed liquid crystal layer 45.

Each pattern of the lower substrate 41 is not shown but is connected to the terminal around the substrate through a conductive line. At this time, the terminal is connected to the mobile phone power through the circuit. Therefore, the voltage is applied to the transparent conductive film pattern through the terminal and the conductive wire. However, when using a keypad made of PDLC panels, these conductive wires do not appear, and only the letters, numbers, and symbols do not use transparent conductive layers. Only the pattern portion may be formed by superimposing a transparent conductive layer and a pattern of another opaque material.

Among characters of the transparent conductive film pattern, which are displayed in the same mode when a character or the like is input into a mobile phone, voltages are simultaneously supplied through terminals while the mode is selected. In this case, all of these terminals are connected to the same power supply in the circuit, and when a mode is selected, a voltage is applied to this power supply, and all of the transparent conductive film patterns shown in this mode are applied to the terminals connected to this power supply at the same time. The keypad may be configured to be displayed together on the screen of the PDLC panel. For example, in the Hangul dial mode, as shown in FIG. 3, the Hangul alphabet may be brightly displayed by a backlight on a keypad made of a PDLC panel.

On the other hand, if you press the mode switch of the mobile phone prepared for mode switching, Arabic numerals appear as shown in Figure 4 instead of the Hangul alphabet for each button on the keypad, and if you press the mode switch again, the alphabet letters for each button will appear on the keypad . In this way, each time you press the mode switch, the keypad displays different groups of letters, numbers, or symbols. In addition, even when the mobile phone is turned 90 degrees in order to use the display window widely, an area corresponding to one key button (an area corresponding to one dome switch) as shown in FIG. Some of the plurality of transparent conductive layer patterns formed in FIG. 9 may be displayed to be rotated by 90 degrees, and may be used corresponding to one mode. Of course, there may be a mode in which all transparent conductive film patterns formed in the button area of the keypad are simultaneously displayed as shown in FIG.

Looking at the operation of the display of the characters, such as the character of the keypad in the above embodiment, according to the mode selection through the mode switch, the character set or number or symbol set corresponding to the mode is displayed on the keypad of the PDLC panel. The user selects a desired letter among the displayed sets and inputs the corresponding letter to be displayed on the display screen of the mobile phone through a corresponding key button combination.

Referring to FIG. 2 again, in the selected mode, a specific potential is applied only to the transparent conductive film patterns 43 constituting the corresponding character set, and the transparent conductive film patterns 43 based on the polymer dispersed liquid crystal layer 45. A ground voltage or a voltage having a different polarity from that of the transparent conductive film patterns 43 is applied to the transparent conductive film 47 forming the common electrode on the opposite side of the transparent conductive film 47. As a result, a potential difference is generated with the polymer dispersed liquid crystal layer 45 interposed therebetween. Then, in the polymer dispersed liquid crystal layer of the transparent conductive film pattern region A, an electric field exists due to a potential difference, and the liquid crystal is aligned in one direction by this electric field. And a transparent state is implemented so that light may transmit only in this part where the liquid crystal is aligned. Accordingly, the light of the backlight layer passes through the transparent conductive film pattern area A as it is and enters the user's eyes, and the user recognizes the letter corresponding to the transparent conductive film pattern.

The color of light indicating the character to be recognized by the user is determined by the color of the backlight as the light source, so that the user can select a desired color when purchasing a mobile phone.

One may think of driving the PDLC panel in the form of an active matrix in order for the PDLC panel to be more flexible as a keypad. In this case, the transparent conductive pattern only forms the pixel electrode of each pixel throughout the PDLC panel and does not need to be formed in the form of a specific character or the like. In this case, a separate drive driver IC may be provided to display characters and the like on the PDLC screen as a keypad keyboard.

The present invention has been described through several embodiments of the present invention, but this is merely an example and may be implemented in various other forms.

Claims (5)

delete delete delete Backlit,
A dome sheet disposed below the backlight layer and provided with a dome switch;
A circuit board under the dome sheet and having a portion electrically opened and closed by the dome switch;
It is placed on the backlight layer, and is provided with a PDLC panel that can be displayed letters, numbers or symbols,
The PDLC panel includes a lower substrate, a transparent conductive layer pattern formed on the lower substrate, a PDLC film layer formed on the transparent conductive layer pattern, a transparent conductive layer on the PDLC film layer and forming a common electrode on the entire surface, and an upper substrate covered on the transparent conductive layer. It is made with
The transparent conductive layer pattern is a pattern in which letters, numbers or symbols to be input are directly displayed.
A plurality of transparent conductive layer patterns are formed in one region of the dome switch, and the plurality of transparent conductive layer patterns are divided into modes and are displayed only in a specific mode. The method of claim 4, wherein
And some of the plurality of transparent conductive layer patterns are formed on the PDLC panel so as to be rotated by 90 degrees.

Images