KR20070061756A - Super-thin type keypad emitting light - Google Patents

Abstract

A ultra-thin light emitting keypad is provided to considerably improve click sensation and switching accuracy by including an elastic board, and minimize influence of static electric or electromagnetic wave by installing a dispersion layer, a static electricity shielding layer, and a noise preventing layer on an EL(Electro Luminescence) device. An ink layer(2) is formed at a lower portion of an elastic board(1). An EL device(3) formed at a lower portion of the ink layer(2). A rear layer(5) is formed at a lower portion of the EL device(3) and includes protrusions(6). A PCB(Printed Circuit Board)(8) includes contact terminals(81) and metal domes(82) positioned to be separated from the contact terminals(81) at a lower portion of the rear layer(5). An attachment layer(4) is formed between the EL device(3) and the rear layer(5).

Description

Ultra-thin luminescent keypad {SUPER-THIN TYPE KEYPAD EMITTING LIGHT}

The present invention relates to an ultra-thin light emitting keypad, in particular, by forming the EL device on the back layer formed on the bottom of the projection to prevent deformation and breakage of the EL element due to the projection, increase the light emission efficiency, brightness, and has an elastic substrate The present invention relates to an ultra-thin light emitting keypad that significantly improves a feeling of click and switching, and has a scattering layer, an electrostatic shielding layer, and an anti-noise layer on the EL device to minimize the effects of static electricity or electromagnetic waves and to provide a clean and uniform light emitting surface. .

In general, the light emitting keypad is applied to a communication device such as a mobile phone and used as a switch device for performing a signal generation or various additional functions, and has a function of identifying keys such as numbers and letters at night or in a dark place. Recently, as the thinning of portable terminals is accelerated, ultra-thin light emitting keypads have been developed and applied.

Conventional LED type light emitting keypads used as light sources of light emitting keypads cannot be manufactured in a thin form due to the characteristics of LEDs, and thus keypads are made relatively thick. In addition, the power consumption according to the LED light emission can be shortened the use time of the battery. In addition, the uniformity of light emission is uneven depending on the arrangement position of the LED, which leads to design difficulties.

Therefore, in order to overcome the limitations of the ultra-thin LED of the conventional LED light emitting keypad, the development of an ultra-thin light emitting keypad to which the EL (Electro Luminescencc) lamp light emitting method (hereinafter referred to as "EL method") is applied.

1 is a cross-sectional view of a conventional EL type light emitting keypad for solving the above problems, and includes a key top 110, an EL metal dome sheet 120, and a printed circuit board 130, and the EL metal dome sheet 120. ) Is composed of an EL sheet 121, a metal dome 123, and a baystrip 122 to realize ultra-thin film and low power consumption.

Looking at the function of the EL-type metal dome keypad, when the key top 110 is pressed by the user, the fixed contact of the metal dome 123 and the printed circuit board 130 by the protrusion 111 located on the back of the key top 110. The terminal 131 is contacted and switched to operate.

However, in the conventional EL type light emitting keypad, the EL sheet 121 is continuously pressurized and impacted by the projection 111, so that there is a high risk of damage or breakage of the EL sheet, thus causing a large problem in the reliability of the EL keypad and There is a problem that causes a drop in the click feeling.

In addition, since the relatively thick key top 110 is positioned on the upper part of the EL sheet 121, and the material is made of silicon having low light transmittance, there is a problem that the light output efficiency is significantly reduced and the luminance is reduced.

On the other hand, such an EL keypad can cause serious problems in product performance under the influence of static electricity and electromagnetic waves. Particularly, powder particles of a light emitting body that emit light generally emit light in a radius of about 20 to 50 μm. There may be a problem in the color of the light or the uniformity of the brightness due to the presence of a shaded portion between and the particles.

Technical challenge

Accordingly, the present invention has been made to solve the above problems, by forming the EL device on the back layer formed on the bottom of the projection to prevent deformation and breakage of the EL element due to the projection and increase the light emission efficiency, brightness and In addition, by providing an elastic substrate, the click feeling and the switching accuracy are significantly improved, and the EL device is provided with a dispersion layer, an electrostatic shielding layer, and an anti-noise layer to minimize the effects of static electricity or electromagnetic waves and to provide a clean and uniform light emitting surface. It is an object of the present invention to provide an ultra-thin light emitting keypad as possible.

Technical solution

In order to achieve the above object,

The present invention is an ink layer formed on the lower elastic substrate; An EL device formed below the ink layer; It provides an ultra-thin light emitting keypad comprising a; back layer formed on the bottom of the EL device having a projection.

The present invention also provides an ultra-thin light emitting keypad further comprising a printed circuit board having a contact point and a metal dome positioned above the contact terminal and spaced apart from the contact terminal.

Further, there is provided an ultra-thin light-emitting keypad which further comprises an adhesive layer between the EL device and the back layer.

The EL device also provides an ultrathin light emitting keypad characterized in that it comprises an EL system for emitting light and at least one of a dispersion layer, an electrostatic shielding layer, and an anti-noise layer on or under the EL system.

Further, at least one of the ink layer, the EL device, the back layer, and the projection provides an ultra-thin light emitting keypad characterized in that it is formed by screen printing.

In addition, the projection provides an ultra-thin light emitting keypad, characterized in that formed on the back layer by thermocompression molding.

In addition, the projection and the back layer provides an ultra-thin light emitting keypad, characterized in that formed integrally.

In addition, the elastic substrate provides an ultra-thin light emitting keypad, characterized in that made of polycarbonate.

Favorable effect

Due to the above characteristic configuration, the following effects are provided. That is, the present invention prevents deformation and breakage of the EL element due to the projections by increasing the EL device on the back layer formed at the bottom of the projections, increases light emission efficiency, brightness, and provides a feeling of click and switching accuracy by providing an elastic substrate. And the dispersion layer, the electrostatic shielding layer, and the noise prevention layer in the EL device to minimize the effects of static electricity or electromagnetic waves, to reduce noise, and provide an effect of providing a clean and uniform light emitting surface.

1 is a cross-sectional view of a conventional EL type light emitting keypad;

2 is a cross-sectional view of an ultra-thin light emitting keypad according to the present invention.

3 is a cross-sectional view of another embodiment of an ultra-thin light emitting keypad according to the present invention;

4 is a cross-sectional view of an EL device of the ultra-thin light emitting keypad according to the present invention.

Best Mode for Carrying Out the Invention

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

2 is a cross-sectional view of an ultra-thin light emitting keypad according to the present invention.

As shown, the ultra-thin light emitting keypad according to the present invention includes an ink layer 2 formed below the elastic substrate 1, an EL device 3 formed below the ink layer 2, and a lower portion of the EL device 3. It is characterized in that it comprises a back layer (5) formed in the and provided with a projection (6). In this case, an adhesive layer 4 may be further included between the EL device 3 and the back layer 5.

The elastic substrate 1 is made of a material having elasticity, the click feeling is improved due to the elastic force, it is configured to enable the keypad operation with a less force to enable the smooth operation of the keypad. That is, when the user presses a predetermined key, only the region of the predetermined key is bent specifically, thereby preventing the region of the unwanted key from bending and switching to realize accurate switching. In addition, when the user releases the pressurized key, it is naturally restored by the elastic force. Although it may be provided with a separate elastic layer, the elastic substrate serves as an elastic layer can be manufactured to be thinner and there is an advantage that the manufacturing process is more simple.

The material of the elastic substrate is not limited as long as the material has elastic force. For example, a resin such as polycarbonate (PC), polyethylene terephthalate (PET), polyurethane, or the like may be selected. Most preferably, polycarbonate (PC) is preferable and an injection molding in the form of a film is preferable. Although the thickness of the board | substrate 1 is not restrict | limited, 100-400 micrometers is preferable for ultra-thinning. It is also good to have excellent light transmittance.

The ink layer 2 is a layer for displaying the keys of the keypad and implements the front shape of the keypad, and is formed by applying ink for the keypad to the lower portion of the elastic substrate 1 by spraying or screen printing. As for thickness, 5-10 micrometers is preferable.

The EL device 3 is a light emitting area, and its structure and manufacturing method are not particularly limited, and the structure and manufacturing method of the EL device 3 disclosed or used in the technical field of the present invention can be selected without limitation. The thickness is preferably 100 to 150 µm in consideration of ultra-thinness and light emitting performance. By placing the EL device 3 close to the front of the keypad, the light output efficiency is further maximized. In addition, since the light loss does not occur due to the key top of the conventional silicon material, the luminance is relatively increased.

A more preferable EL device 3 and a manufacturing method which can be applied to the present invention will be described later with reference to FIG.

The back layer 5 is provided with projections 6 at the bottom thereof to provide better keypad operation, click feeling and effective switching.

The material of the back layer 5 is not particularly limited, and preferably silicon and a polymer resin may be selected.

As a method of forming the protrusions 6 in the lower portion of the back layer 5, the protrusions 6 may be separately provided and adhered to the back layer 5, but more preferably, the protrusions 6 are integrally formed with the back layer 5. It is preferable in terms of durability and strength. That is, liquid silicone or film silicone, polymer resin, etc. are formed by compression molding at 100 to 150 degrees using a molding mold formed corresponding to the back layer 5 and / or the protrusion 6, or by photolithography. It is formed by screen printing an ink for UV curing or IR curing.

As an example of the method of forming the back layer 5 on the EL device 3, it is preferable to provide a separate adhesive layer 4 and to bond them to each other because of excellent adhesive strength. The adhesive material is not limited but may use a printing adhesive that can be printed by screen printing or an adhesive tape. More preferably, a primer used for adhesion may be used.

3 is a cross-sectional view of another ultra-thin light emitting keypad according to the present invention.

That is, as shown in the present invention, a metal dome positioned below the back layer 5 in the configuration, spaced apart from the contact terminal 81 on the contact terminal 81 and the upper contact terminal 81 ( Provided is an ultra-thin light emitting keypad further comprising a printed circuit board 8 having 82).

The printed circuit board 8 is formed with a metal dome 82 and a contact terminal 81.

Therefore, when a key on the keypad is pressed by the user, a specific key region of the elastic substrate is elastically deformed, so that the projection 6 presses the metal dome 82 of the printed circuit board 8 and accordingly the metal dome 82 ) Is in contact with the contact terminal 81 is switched.

4 is a sectional view of one embodiment of an EL device 3 of the ultra-thin light-emitting keypad of the present invention. 4 is only one embodiment, it will be apparent that variations and partial omission of the stacking order of the illustrated structure are all included in the scope of the present invention.

The structure of the EL device 3 of the present invention is most preferably configured as shown in FIG.

In other words, the EL device 3 has an electrostatic shielding layer 31, a dispersion layer 32, an insulating layer 33, a front electrode layer 34, a light emitting layer 35, a dielectric layer 36, The back electrode layer 37, the insulating layer 38, the noise preventing layer 39, and the insulating layer 40 are sequentially stacked. The front electrode layer 34, the light emitting layer 35, the dielectric layer 36 and the back electrode layer 37 form an EL system which is a light emitting structure of the EL device 3.

The manufacturing method of the EL device 3 is preferably formed under the ink layer 2, and is preferably formed by screen printing for thinning.

Except for the static shielding layer 31, the dispersion layer 32, the noise prevention layer 39 in the above configuration is well known in the art, and accordingly, the static shielding layer 31, the dispersion layer 32, noise Forming the prevention layer 39 is a great feature of the present invention and will be described below.

The electrostatic shielding layer 31 is formed to prevent damage to the circuit components and the EL system due to external static electricity generation and serves to discharge the generated static electricity to the printed circuit board 8 or the device case through the ground terminal. . The material may be preferably used as the material is made of a material having high electrical conductivity. Thus, materials such as carbon, copper, silver, and gold may be used.

The dispersion layer 32 serves to improve the dispersibility of light generated in the emission layer 35. Since the dispersion layer 32 is required to transmit light, the dispersion layer 32 is preferably configured as a material having good transmittance, and may include various materials for improving light dispersion. Preferably, various pigments, glass beads, calcium carbonite and the like can be selected.

The noise prevention layer 39 serves to block noise generated when the EL device 3 is operated by an AC power source. This noise prevention layer 39 is preferably configured to be located on the back surface of the EL device 3. The noise can be effectively blocked by using a material with high electrical conductivity. Examples thereof include, but are not limited to, carbon, copper, silver, gold, and the like.

The above embodiments are intended to describe the present invention in detail, and are not intended to limit the present invention. Therefore, modifications, modifications, omissions, etc. that can be applied within the scope of the technical idea of the present invention are defined by the claims. It is included in the scope of the invention.

That is, it is included in the scope of the present invention even if it is formed in the reverse order of the manufacturing procedure in the manufacturing procedure. That is, after forming a back layer, it can also manufacture in order of laminating | stacking an EL device (the formation of its internal structure can also be reversed), an ink layer, and a board | substrate.

Further, the EL sheet may be formed to be specific only to a predetermined region below the ink layer.

The present invention having the above-described structural features prevents deformation and breakage of the EL element due to the projections by forming the EL device on the back layer formed at the bottom thereof, increases light emission efficiency, brightness, and has an elastic substrate. Ultra-light emission, which greatly improves the click feeling and switching accuracy, and the EL device is equipped with a dispersion layer, an electrostatic shielding layer, and an anti-noise layer to minimize the influence of static electricity or electromagnetic waves, reduce noise, and provide a clean and uniform light emitting surface. Provide a keypad. Therefore, the present invention can be suitably used for a keypad having a function of generating a signal or various additional functions and identifying a key such as a number or a letter at night or in a dark place in a communication device such as a mobile phone.

Claims (8)

An ink layer formed under the elastic substrate; An EL device formed below the ink layer; And And a back layer formed under the EL device and having projections. The ultra-thin light-emitting keypad according to claim 1, further comprising a printed circuit board having a metal dome positioned below the back layer and spaced apart from the contact terminal on the contact terminal and the contact terminal. The ultra-thin light-emitting keypad according to claim 1 or 2, further comprising an adhesive layer between the EL device and the back layer. The ultra-thin light emitting keypad according to claim 1 or 2, wherein the EL device comprises at least one of an EL system for emitting light and a dispersion layer, an electrostatic shielding layer, and an anti-noise layer above or below the EL system. . The ultra-thin light emitting keypad according to claim 1 or 2, wherein at least one of the ink layer, the EL device, the back layer, and the projection is formed by screen printing. The ultra-thin light-emitting keypad according to claim 1 or 2, wherein the protrusion is formed by thermocompression molding on the back layer. The ultra-thin light-emitting keypad according to claim 1 or 2, wherein the protrusion and the back layer are integrally formed. The ultra-thin light-emitting keypad according to claim 1 or 2, wherein the elastic substrate comprises polycarbonate.

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