JP2001167655A - Push button switch illumination apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal illumination apparatus of manipulation keys that can reduce the consuming power with lowering price as well as the number of luminous body being as a light source and that has no need to separately illuminate the manipulation keys even though a plural number of manipulation keys were arranged. SOLUTION: It comprises a plural number of manipulation keys, a plural number of switching elements for performing a switching operation by pressing the manipulation keys, which are arranged into a downward direction of the manipulation keys, a rigid body substrate for holding each of the switching elements into a downward direction of the manipulation keys, and a flexibility plate for passing light that is arranged between the manipulation key and the switching element and reflects an incident light from a light source arranged to its side toward the bottom of the manipulation key to be illuminated from the bottom. It inserts the flexibility plate for passing light by pressing the manipulation key and is achieved by the illumination apparatus of push button switch for pressing the switching element on the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cellular phone, a PDA, and the like.
The present invention relates to an illumination device for a push button switch for illuminating a push button switch of a control (operation) device which is frequently used as an operation button of a small portable electronic device such as a (portable information terminal), a calculator, a personal computer, a car audio device, etc. ,In particular,
When operating these devices in a dark place, these controls (operations) are used to make it easier to see the positions of the operation keys to be operated.
The present invention relates to an illumination device for a push button switch that illuminates operation keys of the device from inside.

[0002]

2. Description of the Related Art The prior art will be described below using a push button switch of a cellular phone as an example. FIGS. 3 and 4 show an operation key (numerical key or the like) of a mobile phone and an illuminating device thereof as an example of a conventional illuminating device of a push button switch.
FIG. 3 is an exploded perspective view showing a main part of a mobile phone having a conventional push-button switch lighting device, and FIG. 4 is a cross-sectional view at a position of an operation key.

As shown in FIG. 3, a mobile phone has a circuit board and a circuit board 53 constituting an entire circuit board arranged in an upper case 51 and a lower case 52 in a case. Above the substrate 53, there is a keypad 55 in which a large number of operation keys 54 for inputting a telephone number or the like by being pressed are integrally formed, and below the operation keys 54 of the keypad 55. A plurality of switching elements 56 corresponding to the respective operation keys 54 are fixedly held on the substrate 53. The operation keys 54 provided on the keypad 55 are inserted through the insertion holes 51a of the operation keys provided on the upper case 51 and protrude from the surface of the upper case.

Further, a liquid crystal display device 57 for displaying a telephone number or the like to be talked on is provided on the substrate 53, and can be visually recognized through a display window 51b provided on the upper case 51. Further, the board 53 is provided with electronic components such as an IC for controlling the mobile phone, various devices for reception and transmission, and components as a mobile phone such as an antenna, which are directly related to the present invention. Therefore, the illustration is omitted here, and the description is also omitted.

[0005] Between the switching elements 56 on the substrate 53, an LED (light emitting diode) is used as an illuminating device for illuminating the operation keys 54 arranged on the keypad 55 from inside.
And the like are disposed between the respective switching elements 56. Then, the upper case 51 and the lower case 5
A mobile phone is constructed by assembling a substrate 53 with various components attached thereto and a keypad 55 provided with a large number of operation keys 54 and assembling them together in a case.

FIG. 4 is a cross-sectional view at the position of the operation key. As shown in the figure, the operation key 54 of the keypad 55 is located above the switching element 56 disposed on the substrate 53.
Are arranged, and the switching element 56 is pressed by a convex portion 54 a provided on the lower surface of the operation key 54 to perform switching by operating the operation key 54. As shown in the figure, a light-emitting body 58 such as an LED (light-emitting diode) is arranged between the switching elements 56 as an illumination device for illuminating the operation key 54 from the inside, and as shown by an arrow C, Light is projected on the lower surface of the keypad 55.

The keypad 55 is generally formed of a transparent or translucent and flexible material, and has a printing surface 54b on which numbers or symbols are printed with opaque printing ink on the upper surface of the operation keys 54. Thereby, the operation key 54 of the keypad 55 is pressed, the switching element 56 on the substrate 53 provided below is pressed, the switching element 56 is switched, and the light projected from the lower surface of the keypad 55 is emitted. It is configured such that numbers or symbols printed with opaque printing ink on the upper surface of the operation keys 54 can be read through the keypad 55.

The illumination device for illuminating the operation keys 54 of the portable telephone from the inside is provided so that the position of the operation keys 54 can be seen when the portable telephone is operated in a dark place. Generally, the light is turned on by operating any key, and is automatically turned off when no key is operated for a predetermined time. When the illuminant 58 such as an LED is turned on to illuminate the keypad 55 from below, the light from the illuminant 58 is transmitted to the transparent or translucent portion of the operation key 54 or the operation key 54 and the upper case. The internal light is projected to the outside through a gap between the operation key provided in the unit 51 and the insertion hole 51a, and the operation key 54 is illuminated so as to be readable even in a dark place.

When the illuminator 58 such as an LED for illuminating the operation key 54 is arranged at a distance from the periphery of the operation key 54, the light is blocked by a switching element 56 or the like in the middle, so that the operation key 54 is sufficiently illuminated. Since illumination cannot be performed, in the related art, as shown in FIGS. 3 and 4,
In order to illuminate two to four operation keys 54 with one LED, a large number of LEDs have to be arranged close to the operation keys 54.

[0010] For this reason, the conventional operation key illumination device uses a large number of LEDs (light sources), which inevitably increases the cost. Furthermore, when illuminating the operation key, a large number of LEDs are used. Must be turned on at the same time, so that the power consumption is not negligible as a whole and affects the life of the battery. For this reason, in a PDA, a personal computer, or the like, in which a large number of operation keys are arranged, the liquid crystal display device is illuminated with a backlight, but the keyboard in which the operation keys are arranged has no illumination, and is dark. In many places, it was difficult to operate the keyboard (operation keys).

[0011]

SUMMARY OF THE INVENTION The present invention solves these problems and reduces the number of illuminants serving as light sources, thereby reducing the cost and power consumption. Illumination device of a push button switch), and further provides an internal illumination device of an operation key which does not need to individually illuminate these operation keys even when a large number of operation keys are arranged. It is.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a plurality of operation keys for operating a device, and a plurality of operation keys disposed below the plurality of operation keys. A plurality of switching elements that perform switching by a plurality of switching elements, a rigid substrate that holds the plurality of switching elements below the plurality of operation keys, and a plurality of switching elements between the plurality of operation keys and the plurality of switching elements. And a flexible light guide plate for projecting light incident from a light source disposed on a side surface toward the lower surface of the plurality of operation keys to illuminate the operation keys from below, and comprising: By pressing the switching element on the substrate through the flexible light guide plate to perform switching. It is intended.

Preferably, the light guide plate has a hologram on a surface thereof, and diffracts light incident from a light source arranged on a side surface by the hologram and projects the light toward the operation keys. It is preferable that the hologram formed on the light guide plate is discontinuously arranged only at a position where light is projected toward the operation key. Preferably, the plurality of operation keys for operating the device are a plurality of operation keys integrally formed as a keypad. Alternatively, it is desirable that the substrate is a circuit board.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. 1 and 2 show an example of a mobile phone to which a lighting device for a push button switch according to the present invention is applied. FIG. 1 is an exploded perspective view, and FIG. 2 is a cross-sectional view at a position of an operation key. As shown in FIG. 1, a mobile phone to which the illumination device for a push-button switch of the present invention is applied has an upper case 1 similar to the prior art.
A rigid substrate 3 which serves as a circuit board and constitutes the entire substrate is arranged in a case composed of the lower case 2 and the lower case 2. Above the substrate 3, a keypad 5 on which a plurality of operation keys 4 for inputting a telephone number or the like by pressing are arranged. Below the operation keys 4 of the keypad 5, a plurality of switching elements 7 corresponding to the respective operation keys 4 are provided via a light guide plate 6 described later.
Is held on the substrate 3. The operation keys 4 provided on the keypad 5 penetrate through the insertion holes 1 a of the operation keys provided on the upper case 1 and protrude from the surface of the upper case 1.

Further, the substrate 3 is provided with a liquid crystal display device 7 for displaying a telephone number or the like to be used for a call.
Through the display window 1b provided in the camera. Furthermore, the substrate 3 is provided with electronic components such as an IC for controlling the mobile phone, various devices for reception and transmission, and components as a mobile phone such as an antenna, which are directly related to the present invention. Therefore, the illustration is omitted here, and the description is also omitted.

An operation key 4 arranged on the keypad 5 is provided between the keypad 5 and the switching element 7 on the substrate 3.
A light guide plate 6 is provided as an illumination device for illuminating the inside from inside. The light guide plate 6 is formed of a transparent and flexible material, and projects light emitted from a light source 8 having a linear or a plurality of dot-shaped light emitters on the lower surface of the keypad 5. is there. Then, between the upper case 1 and the lower case 2, a substrate 3 on which various components are mounted, a light guide plate 6 for illuminating the operation keys 4 from the inside, and a keypad 5 provided with a large number of operation keys 4 Are assembled to form a mobile phone.

FIG. 2 is a sectional view at the position of the operation key 4. As shown in FIG. 2, the keypad 5 is disposed above the switching element 7 disposed on the substrate 3 via the light guide plate 6.
Operation keys 4 are arranged. A convex portion 4a is provided on the lower surface of the operation key 4, and when the operation key 4 is pressed, the convex portion 4a presses the switching element 7 on the substrate 3 via the flexible light guide plate 6. , For switching.

This keypad 5 is, as in the prior art,
It is formed of a transparent or translucent and flexible material, and a printing surface 4b on which numbers or symbols are printed with opaque printing ink is provided on the upper surface of the operation keys 4. By pressing the convex portion 4
a presses the switching element 7 on the substrate 3 via the flexible light guide plate 6 to perform switching, and the light projected on the lower surface of the keypad 5 passes through the keypad 5 to form an opaque printing ink. Is configured to be able to read a number or a symbol printed by.

The light guide plate 6 is a lighting device for illuminating the operation keys 4 of the present invention from the inside. As in the prior art, when operating the mobile phone in a dark place, the position of the operation keys 4 can be seen. It is provided so that it can be performed. The light is turned on by operating any key, and is automatically turned off when no key operation is performed for a predetermined time. The illumination device is configured such that when the keypad 5 is turned on to illuminate the keypad 5 from below, a transparent or translucent portion of the operation key 4 or an insertion hole between the operation key 4 and the operation key provided on the upper case 1 is provided. The light inside is transmitted to the outside through a gap or the like with 1a, and illuminates the operation key 4 to the extent that it can be read even in a dark place.

A light guide plate 6, which is a lighting device for illuminating the operation keys 4 from the inside, is substantially the same as a known light guide plate used as a backlight of a liquid crystal display device, and is shown in FIG. As shown in FIG. 2, the light source 8 is provided on one side surface, and as shown in FIG. The light is projected on the lower surface of the operation key 4. This light guide plate 6 can reflect light by a prism array formed at approximately 45 degrees and refract it by approximately 90 degrees, as is well known as a backlight of a liquid crystal display device. A hologram may be formed on the lower surface of the operation key 4 by diffracting light approximately 90 degrees by the hologram.

The size of the refraction surface 6a for refracting the light incident on the inside of the light guide plate 6 by 90 degrees and projecting it on the lower surface of the operation key 4 is within the range of the light transmitted through the operation key 4 and projected to the outside. In order to avoid light loss due to projecting light from the unnecessary portion to the lower surface of the operation key 4, as shown in FIG. 1, it is only necessary to project light on the lower surface of the operation key 4. It is desirable to arrange them continuously. The refracting surface 6a is drawn in a quadrangle in FIG. 1, but may be formed in any shape such as a circle and an ellipse. Also,
The refraction surface 6a is desirably a refraction surface that forms a hologram on the surface and diffracts the light by the hologram in consideration of the easiness of processing in forming such a part and the efficiency of refracted light.

When the switching element 7 on the substrate 3 is pressed via the light guide plate 6 in this manner, the light guide plate 6 is naturally greatly deformed and the position of the refraction surface 6a is changed. The amount of light projected on the lower surface changes greatly at the deformed portion. However, the illumination of the operation key 4 is provided so that the position of the operation key 4 can be seen when operating in a dark place. There is no trouble at all.

In FIG. 2, the keypad 5, the light guide plate 6,
Although the switching elements 7 on the substrate 3 are drawn so as to have a sufficient space between them, in actuality, in order to reduce the deformation of the light guide plate 6 and to stabilize the position, the switching elements 7 adhere to each other, or It is desirable to arrange at least at a close position.

In the above description, the operation key 4 arranged on the keypad 5 has been described as an operation key for inputting a telephone number or the like, but this operation key is arranged on the flexible keypad 5. However, the present invention is not limited to this, and there is no problem even with a hard operation key used for a keyboard or the like. In addition, the switching element 7 is not limited to the mechanical switching element illustrated in the drawing, but may be any switching element such as a sheet-like switching element that switches by changing the resistance by pressing. Is also possible.

Of course, the illumination device of the push button switch according to the present invention is not limited to the configuration described above.
The application is not limited to the push button switch of the mobile phone shown in the embodiment, and various control (operation) devices such as a mobile phone,
The present invention can be applied to small portable electronic devices such as PDAs (Personal Digital Assistants) and calculators, personal computers, car audios, and the like.

[0026]

The illumination device for a push-button switch according to the present invention is configured as described above. Therefore, the number of illuminants serving as a light source is reduced, and the operation key is reduced in price and power consumption is reduced. Can provide internal lighting equipment,
Furthermore, even if a large number of operation keys are arranged, it is possible to provide an internal illumination device for operation keys that does not need to individually illuminate these operation keys.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an example of a mobile phone to which a lighting device for a push button switch of the present invention is applied.

FIG. 2 is a sectional view of the embodiment of FIG. 1 at the position of an operation key.

FIG. 3 is an exploded perspective view showing a main part of a mobile phone having a conventional push button switch lighting device.

4 is a cross-sectional view of the embodiment of FIG. 3 at the position of an operation key.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper case 1a Insertion hole 1b Display window 2 Lower case 3 Substrate 4 Operation key 4a Convex part 4b Printing surface 5 Keypad 6 Light guide plate 6a Refraction surface 7 Switching element 8 Light source

Claims (5)

[Claims] 1. A plurality of operation keys for operating a device, a plurality of switching elements arranged below the plurality of operation keys, respectively, for switching by pressing the operation keys; A rigid substrate for holding an element below the plurality of operation keys, and a light source that is disposed between the plurality of operation keys and the plurality of switching elements, and that receives light incident from a light source disposed on a side surface. A flexible light guide plate that projects toward the lower surface of the plurality of operation keys and illuminates the operation keys from below, and by pressing the operation keys, through the flexible light guide plate A lighting device for a push button switch, wherein the switching is performed by pressing the switching element on the substrate. 2. The light guide plate has a hologram on its surface, and diffracts light incident from a light source disposed on a side surface by the hologram and projects the light toward the operation keys. Item 2. An illumination device for a push button switch according to item 1. 3. The push button switch according to claim 2, wherein the hologram formed on the light guide plate is discontinuously arranged only at a position where light is projected toward the operation key. Lighting equipment. 4. A plurality of operation keys for operating the device,
2. The illumination device for a push button switch according to claim 1, wherein the illumination device comprises a plurality of operation keys integrally formed as a keypad. 5. The illumination device for a push button switch according to claim 1, wherein said substrate is a circuit board.