JPH011019A - soft keyboard - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a keyboard, and more particularly to a soft keyboard that performs switching by short-circuiting between electrodes using conductive sponge, rubber, or other elastic material when pressurized. .

[Conventional technology]

Conventional keyboards have different contact structures depending on the type, such as mechanical types, conductive rubber types, membrane type types, and capacitance variable type types, but in all cases, the contact structure is at the tip of the back of the rigid key top. The configuration was as shown in FIG. 5, in which a movable contact was provided on the side of the circuit board, and a fixed contact was provided on the substrate at a position facing the movable contact.

In addition, related technologies include 1, for example, Japan Office Machinery Manufacturers Association [Office Machinery JNQ109. January 1986 issue, No. 2
It is described on pages 9 to 35.

[Problem that the invention seeks to solve]

According to the above-mentioned conventional technology, a guide part for moving the rigid key top up and down, a spring for urging the key top upward except when it is operated, and a spring that prevents the key top from being removed when the key top is pressed upward,
Furthermore, an outer frame is required at least to cover and protect these structures and contact portions from the outer layer, and it is necessary to have a large number of parts and to assemble these parts precisely.

For this reason, there is a limit to how compact and thin the keyboard can be made as a whole, and because there are many rigid parts such as the key top and outer frame, the overlap is also large, which is a major bottleneck in reducing the size and weight of personal information devices that are highly portable. ing. In addition, since there are a large number of four parts, the manufacturing cost is high, and in order to use it for personal devices and appliances that strongly require low cost, it is necessary to further reduce the price.

Furthermore, in small personal information devices.

Portability: From the perspective of further improving F performance, we want to make the product as small and as thin as possible, but on the other hand, we want the display screen to be as large as possible to make it easier to see, which are two needs that are difficult to reconcile with each other. exist.

In order to achieve both of these requirements, a transparent keyboard may be placed on the front glass plate of an LCD, which is often used as a small display device, to save space for mounting the keyboard.

However, making a conventional keyboard transparent requires making all of the many parts that make up the complex mechanism transparent, which is impossible.

The purpose of the present invention is to construct a transparent keyboard using the surface glass plate of an LCD, and to reduce the size of the entire product while increasing the display screen in small personal information devices, etc.
The aim is to make the device thinner and improve its portability and operability.

[Means for solving problems]

[Above] J is a transparent sponge or rubber that forms a plurality of transparent electrode patterns on the surface glass plate of an LCD and becomes conductive by applying pressure on the glass plate.

Another elastic material (hereinafter referred to as a pressurized conductive elastic material) is arranged so that one surface forms an operation surface corresponding to the key top of a conventional keyboard, and the other surface contacts the surface glass plate. and at the contact portion of the plurality of electrode patterns provided corresponding to each key, the plurality of electrode patterns are short-circuited by the pressurized conductive elastic material to detect an input key. This is achieved by

[Effect]

When a certain key is selected and the operating surface of the pressurized conductive elastic material is pressed with a fingertip, the pressed portion of the pressurized conductive elastic material is compressed, and the electrical resistance of the core portion is reduced. At the contact point, a plurality of electrode patterns provided on the front glass plate of the LCD are short-circuited as shown in FIG. 1, and the selected key is detected.

〔Example〕

An embodiment of the present invention will be described below with reference to each section. L.C.
As shown in FIG. 1, the D30 has a liquid crystal layer 33 sealed between an upper glass substrate 31 and a lower glass substrate 32, and a liquid crystal layer 33 is sealed between the upper glass substrate 31 and the lower glass substrate 32, respectively. Transparent electrode portions 34 and 35 corresponding to display elements are formed. A lower polarizing plate 36 is provided on the upper surface of the upper glass substrate 31, and a lower polarizing plate 37 and a reflecting plate 38 are provided on the lower surface of the lower glass substrate 32.
are arranged, and these are attached and fixed to the substrate 40 by the outer frame 39. A control circuit 41 is provided on the back surface of the substrate 40 to control the voltage applied to the electrode portions 34 and 35 to turn on and off each display element in accordance with the screen desired to be displayed.

A window portion 42 is formed on the upper surface of the outer frame 39, and the upper polarizing plate 36 serves as a front glass plate of the LCD 30. Two types of transparent electrode patterns, electrodes 2 and 3, are formed on the surface of the upper polarizing plate 36. The electrode pattern is provided with a contact portion 4 where the electrodes 2 and 3 are close to each other, as shown in FIG. Such contact portions 4 are provided on the upper polarizing plate 36 in the number of required keys, and are arranged corresponding to the arrangement of each key on the keyboard. FIG. 3 shows an example of the key arrangement and electrode pattern.

On the upper surface of the upper polarizing plate 36 having the electrode pattern as described above, conductive metal particles 11 are mixed inside, and a transparent plate-like material having elasticity and load-displacement characteristics as shown in FIG. 6 is formed. A pressurized conductive sponge 10.

It is attached by a front panel 43.

The characteristics shown in Figure 6 are considered ideal from an ergonomic point of view in order to prevent m* from touching the fingertips during long-time use of the keyboard, high-speed input, and erroneous input due to unstable finger movement. It is a characteristic that

The pressurized conductive sponge 10 is usually an insulator with a resistance of several MΩ, but it is easily compressed by pressing with a fingertip, and the conductive metal particles 11 mixed inside come close to each other and the core It has a characteristic that the resistance value of t's decreases to about several ohms.

The bottom surface of the pressurized conductive sponge 10 is provided with the LCD 30.
The protruding portion 17 is provided only at the cylindrical portion that comes into contact with the contact portion 4 provided on the upper polarizing plate 36.
The pressurized conductive sponge 10 is in contact with the protruding portion 17 only at the contact portion 4 . Further, on the upper surface of the pressurized conductive sponge 10, each key is partitioned with a notch 12 provided at the boundary between the key and the adjacent key. The characters, symbols, etc. that each key represents are either printed thinly on the top of the divided area on the top surface of the pressurized conductive sponge 10 to the extent that the display contents on the LCD 30 are not difficult to see, or are shaped in small recesses. There is.

In the example shown in FIG. 3, nine electrodes 2 corresponding to the number of keys are connected to a positive potential, and one shared electrode 3 is connected to a negative potential.

The operation of detecting an input key by the keyboard configured as described above will be described below.

Since the pressurized conductive sponge 10 provided to cover the upper part of the display screen of the LCD 30 is transparent as described above,
As shown in FIG. 2, the display contents of the LCD 30 can be seen through the keyboard section.

While viewing the displayed content, press the pressurized conductive sponge 10 with your finger at the location corresponding to the key you wish to input.

The pressed conductive sponge 10 is compressed at the pressed part,
The electrical resistance of the lead portion is reduced, and the electrodes 2 and 3 provided on the upper polarizing plate 36 are short-circuited at the contact portion 4. Therefore, by detecting the point where the voltage level of the voltage 142 becomes a negative potential, the input key can be detected. In addition, when pressing the pressurized conductive sponge 10 with your finger in the above,
In order to prevent adjacent keys from being input, the center of the area defined by the notch 12 on the surface of the pressurized conductive sponge 10 is
” You can press it as “cheap”.

〔Effect of the invention〕

According to the present invention, the coordinate input is performed by short-circuiting the electrodes using the switching action of the pressurized conductive elastic material by pressing the fingertips. Therefore, the keyboard can be formed with a simple configuration and a small number of parts, making it compact and thin. easily convert into
Because it is lightweight and can be manufactured at low cost, it is particularly suitable for use in personal information devices that are small, thin, lightweight, compact, and frequently used as a portable device, as shown in Figure 2. We can provide you with a well-reliable keyboard.

In particular, according to the present invention, the pressurized conductive elastic material and the electrodes are made transparent, the front glass plate of the LCD is used as a substrate, the rSi electrode is provided on the glass plate, and the pressurized conductive Because of the structure in which the elastic material is arranged, the keyboard in conventional personal information devices occupies a certain amount of space, which hinders miniaturization of the devices.However, when the keyboard according to the present invention is used in personal information devices,
The display can be made as large as possible while making the device smaller. Although the smaller the device, the better it is for portable use, it solves the conventional problem that the display becomes smaller, making it difficult to see and conversely worsening operability. can do. As a result, it is possible to provide a personal information device that is small, lightweight, compact, and easy to operate.

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view showing an embodiment of the present invention, FIG. 2 is a perspective view showing an example using a soft keyboard according to the present invention, and FIGS. 3 and 4 are electrode pattern arrangement on a glass plate. FIG. 5 is an enlarged sectional view of a conventional keyboard, and FIG. 6 is a diagram showing ideal load-displacement characteristics of the keyboard. 2... Electrode, 3... Electrode, 4... Contact portion, 10.
... Pressurized conductive sponge, 11 ... Conductive metal particles, 12
... cut, 17 ... protrusion, 30 ... LCD,
36...” Partially unbiased 1 Illustrations 2 Words 4 Days 5 Words

Claims (1)

[Claims] 1. One surface forms an operation surface, and the other surface is provided on the surface glass plate of a liquid crystal display device (LCD) by a transparent pressurized conductive elastic material placed on the surface glass plate of the LCD. A soft keyboard is characterized in that key input is performed by short-circuiting multiple transparent electrodes.