JP2836582B2 - Key input device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key input device such as a portable terminal or a keyboard, and more particularly to a key input device provided with a light emitting means so that key input can be performed even in the dark.

[0002]

2. Description of the Related Art Heretofore, this type of key input device irradiates reflected light of illumination of a display unit from the side or obliquely above the key top, or transmits light of a light emitting diode to a side surface of the key top by a light transmitting optical waveguide. Illuminated to enable key input in the dark.

[0003]

The first problem is that in the prior art, the irradiation of the key top portion becomes uneven. The reason is that the light source is located at a position distant from the position where the keytop is arranged, and the light is emitted from the upper surface or side surface of the keytop.

It is an object of the present invention to provide a key input device which irradiates a sufficient amount of light to a key top while maintaining a structure capable of key input, and enables input even in darkness.

[0005]

The key input device of the present invention has a light guide path (4 in FIG. 1) made of a translucent resin capable of entering and diffusing light. And a structure that enables simple key input.

The key input device of the present invention has a light source in a space between the key tops of the board on which the key tops are mounted. A light guide path is formed from the light source to the keytop. The light that has entered the light guide path is guided toward the keytop. Light is diffused at the key top by using a resin having a light diffusing property for a portion serving as the key top. By uniformly entering and diffusing light from the light guide path from above, below, left and right directions of the key top, uniform irradiation of the key top is enabled.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is an external top view of a key input device according to an embodiment of the present invention. In the figure, parts other than the key top 6 are covered with a molding material 7. Except for the key tops 6, all are arranged below the molding material.

FIG. 2 shows the molding material 7 of the key input device of FIG.
FIG. 3 is a sectional view taken along the line AA in FIG. 2, and FIG.
FIG. 3 is a sectional view taken along line BB of FIG. 2. The key top 6 made of a light-transmitting material is used as the key top lower layer 6 ′ of the light guide path 4.
And the thin portion 4a of the light guide path 4 projects toward the spacer 5 in all directions. The light guide path 4 covers almost the entire surface of the substrate 1, and the spacer 5 and the key top lower layer 6 ′ are formed by thickening a part of the light guide path 4. Inside the spacer 5 is a light emitting diode 3 mounted on the substrate 1. That is, the light emitting diode 3 is surrounded by the spacer 5. The spacer 5 is fixed to the surface of the substrate 1. That is, the light guide path 4 is fixed to the substrate 1 by the spacer 5.

The spacer 5, the light guide path 4, and the key top lower layer 6 'are made of integrally molded translucent silicone rubber, and the key top lower layer 6' is made of a translucent molding material. And is integrally molded with the key top 6.

On the lower surface of the substrate 1, an electrode 2 serving as a contact for key input and a thin flat spacer 8 are mounted. The electrodes of the light emitting diode 3 and the drive circuit are mounted on the substrate 1, but the circuit is not shown.

When the key top 6 is depressed, the thin portion 4
While a is deformed, the convex portion 6 ′ a on the lower surface of the key top lower layer portion 6 ′ pushes the electrode 2 and comes into contact with the electrode 10 of the substrate 9 to enable key input. The light emitting diode 3 is arranged between four adjacent key tops 6 on the upper surface of the substrate 1. Specifically, the light emitting diode 3 is mounted on a cross point of a diagonal extension line of the square key top 6.

The light from the light emitting diode 3 is applied to the spacer 5
Through the light guide path 4 to reach the key top lower layer 6 '. The arriving light is transmitted to Key Top 6,
Irradiate.

In the embodiment of the present invention, the light emitted toward the keytop 6 through the light guide 4 is
As a result, the light reaches the key top 6 without dimming, and further emits light toward the center of the key top 6.

According to the embodiment of the present invention, light from the light emitting diode 3 spreads in the thin light guide path 4 covering the substrate 1 in all directions, and reaches the key top lower layer 6 ′ and the key top 6 from all directions. Therefore, one key top 6 emits light from the plurality of light emitting diodes 3,
The light amount of the key top 6 increases. Light emitting diode 3
Are arranged between four adjacent key tops, so that it is not necessary to increase the interval between the key tops 6 for mounting the light emitting diodes 3. The light emitting diode 3
May be mounted between two keytops, at the expense of some mounting area.

Although the light guide path 4 is made of silicon rubber, the material is not limited to this, and any material having flexibility and translucency may be used. The key top 6 is made of a material different from that of the key top lower layer 6 ', but may be the same. Further, the light guide path 4
In order to prevent the light being guided from the light emitting diode 3 toward the key top lower layer 6 from being radiated to the outside, a reflective layer may be formed on the surface. Thereby, the light emission amount of the key top 6 further increases.

As described above, according to the embodiment of the present invention, in a key input device having a plurality of key tops 6 for key input, a plurality of light sources ( A light emitting diode 3), a substrate 1 on which the key tops and the light source are mounted, and a light guide path 4 provided between the lower portion of the key tops and the substrate, for receiving light from the light source and guiding the light to the lower portions of the key tops. And key top 6
The key input device is characterized in that the key input device emits light by light guided by the light guide path 4.

The light guide path 4 is preferably formed so as to cover the surface of the substrate 1. In this case, the light guide path 4 has a thin portion 4a connected to a lower portion of the key top to form a key stroke, and guides light from a light source to the lower portion 6 'of the key top via the thin portion 4a. The light guide path 4 and the keystroke forming portion can be integrated. Further, since the substrate 1 is covered by the light guide path 4, dust does not adhere to the electrodes of the substrate, and malfunction due to dirt can be prevented.

Since the light sources are arranged between the four adjacent key tops 6, the distance between the key tops can be prevented from being widened by the arrangement of the light sources.

Further, by forming a reflection layer for confining light in the light guide path on the surface of the light guide path 4, it is possible to prevent the light of the light source from leaking out and increase the light emission amount of the key top. .

[0021]

The effect of the present invention is that the light can be transmitted to the keytop without attenuating the light emission. Thereby, the key top can be irradiated evenly.

The reason for this is that the light guide path integrally formed on the lower layer of the keytop gives the directionality of light.

[Brief description of the drawings]

FIG. 1 is a top view of an embodiment of the present invention.

FIG. 2 is a top view of the key input device of FIG. 1 when a molding material is removed.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Electrode 3 Light emitting diode 4 Light guide path 5 Spacer 6 Keytop 6 'Keytop lower part 7 Molding material 8 Flat spacer 9 Substrate

Claims (6)

(57) [Claims] 1. A key input device having a plurality of key tops for key input, comprising: a plurality of light sources disposed in a space between the key tops; and a switch operated by pressing the key tops. A substrate having a light source mounted on a surface thereof, and the key disposed between the key top and the light source.
A light guide path formed integrally with the top and receiving light from the light source and guiding the light to a lower portion of the key top, wherein the light guide path is deformed by pressing the key top to form a key.
A key input device which forms a stroke and emits light by light guided from below by the light guide path. 2. The key input device according to claim 1, wherein the light guide path is formed so as to cover a surface of the substrate. 3. The light guide path has a thin portion connected to a lower portion of the key top to form a keystroke, and guides light from the light source to a lower portion of the key top via the thin portion. 3. The key input device according to claim 2, wherein: 4. The key input device according to claim 3, wherein the light source is disposed in a space between four adjacent key tops. 5. The key input device according to claim 3, wherein a reflection layer for confining light in the light guide path is formed on a surface of the light guide path. 6. The light guide path includes a spacer surrounding the light source, wherein the spacer is fixed to the substrate, and light from the light source is introduced into the thin portion via the spacer. 4. The key input device according to claim 3, wherein: