JP2004247103A - Keybutton illuminating device and portable electronic apparatus using same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a keybutton illuminating device wherein an operation part of a keybutton is illuminated brightly and uniformly, and to provide a portable electronic apparatus using it. <P>SOLUTION: This portable electronic apparatus 1 has a case comprising a front case 2 and a rear case 3. In the front case 2, an opening 2a is formed to expose operation parts such as number keys of the operation part, and a light diffusion sheet 13 is provided to cover around the opening 2a. The light diffusion sheet 13 diffuses the light irradiated from an LED11 arranged in the front case 2 to the front case 2, and the diffused light is guided to the keybutton 7. Thereby, the light which is not conventionally used to illuminate the keybutton 7 can be used to illuminate the keybutton 7, so that the keybutton 7 can be uniformly illuminated and brightness can be increased. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a key button illuminating device and a portable electronic device using the same, and more particularly to a key button illuminating device capable of effectively guiding light from a light source (light emitting diode) for illuminating a key to a key portion. The present invention relates to a device and a portable electronic device using the same.
[0002]
[Prior art]
2. Description of the Related Art In electronic devices, in particular, mobile electronic devices such as mobile phones, PHS (Personal Handyphone System) phones, and PDA (Personal Digital Assistant) devices, there is a demand for weight reduction, reduction in power consumption, reduction in component costs, and the like. A portable telephone or a PHS telephone has a numeric keypad, a function key, a direction key (or a cross key), etc., which also serves as a character input. A mobile phone or a PHS phone has a built-in light source for illuminating the keys so that the keys can be operated even in dark places such as stairs and underpasses or outdoors at night. As the light source, an LED (light emitting diode) having the features of being small and lightweight, generating almost no heat, and having extremely low power consumption is used. Each LED has a relatively narrow light irradiation range and an insufficient amount of light. Therefore, a plurality of LEDs are used for illuminating the key.
[0003]
A mobile phone or a PHS phone uses a battery as a power source, and is usually used with the power turned on to enable standby. In order to enable continuous use for several hundred hours in the standby state, it is important to reduce the current consumption of the circuit. Therefore, although the current consumption of the LED is small, the smaller the number of LEDs used, the better. Therefore, it is conceivable to reduce the number of LEDs. If the number of LEDs is reduced, current consumption can be reduced. However, when the key buttons are illuminated (illuminated), illumination unevenness appears on the key operation surface, and overall This results in illumination with insufficient brightness, which degrades the commerciality of the portable electronic device. Therefore, in a portable electronic device on the market, a device is devised so that the key buttons are uniformly illuminated while the number of LEDs used is reduced as much as possible.
[0004]
5A and 5B show the appearance of the portable electronic device, wherein FIG. 5A shows the front, FIG. 5B shows the side, and FIG. 5C shows the back. Here, it is assumed that the mobile electronic device is a mobile phone.
As shown in FIGS. 5A to 5C, the portable electronic device 1 includes a front case 2 (key button attachment member) and a rear case 3 as housing parts. The front case 2 and the rear case 3 are made of resin or metal, and the front case 2 and the rear case 3 are fixed from the back using screws 4a to 4d. In the front case 2 or the rear case 3, a printed circuit board (not shown) and a battery (not shown) on which electronic circuits (a CPU unit, a memory, a wireless unit, a signal processing unit, etc.) are mounted are mounted. As shown in FIG. 5A, on the front of the front case 2, a display unit 5 formed by a liquid crystal display (LCD) and numeric keys (numerical keys 0 to 9, #, *, etc.) formed by a plurality of key buttons 7 are provided. A key operation unit 6 mainly including symbol keys and function keys such as ON, OFF, and CLR is provided.
[0005]
FIG. 6 shows the back surface of the front case 2. An opening 61 serving as a display window of the display unit 5 is provided at an upper portion of the front case 2, and an opening 62 into which the respective key tops of the key buttons 7 are inserted is provided below the opening 61. I have. Further, screw holes 63 for fixing the rear case 3 to the front case 2 by screwing are provided at four corners of the front case 2.
[0006]
FIG. 7 shows a conventional key button lighting device. FIG. 7 shows an AA cross section in FIG.
Openings 2a for exposing each of the key buttons 7 are provided on the upper surface of the front case 2, and upper portions of the key buttons 7 project from each of the openings 2a in order to facilitate the operation by the user. Key information (1, 2,... 0, *, #, etc.) such as numbers is printed (or engraved, pasted with a seal, etc.) on the bottom surface or the top surface of the key button 7. In the front case 2, a transparent or translucent rubber sheet 8 having an inverted concave cross-sectional shape is disposed on the ceiling surface, and the key buttons 7 are formed on the upper surface thereof by using an adhesive or the like. Is affixed. A convex portion 8a is formed on a portion of the ceiling surface of the rubber sheet 8 which faces each of the key buttons 7. A substrate 12 having a predetermined wiring pattern is provided below the rubber sheet 8, and a metal dome contact 10 having a dome-shaped bulging surface is bonded to the upper surface thereof so as to face each of the projections 8a. It is attached using an agent or the like. On the surface of the metal dome contact 10, a light diffusion sheet 9 (which has been subjected to processing such as mirror finish, satin finish, etc.) for diffusing light from the horizontal direction upward is adhered. An LED 11 is provided between the metal dome contacts 10, and a lead wire or an electrode of the LED 11 is connected to a predetermined position of a driving wiring pattern formed on the substrate 12.
[0007]
FIG. 8 is an enlarged view of a part a of FIG. With reference to FIG. 8, a description will be given of key illumination of a conventional configuration. First, when one of the key buttons 7 is pressed, the rubber sheet 8 on the pressed surface is deformed, and the convex portion 8a at that portion is lowered, and the light diffusing sheet 9 and the metal dome contact 10 are deformed by the convex portion 8a. Then, it comes into contact with the wiring pattern on the substrate 12 immediately below and connects the patterns (switch-on). By the connection between the patterns, the LED 11 connected to the pattern is energized and turned on. In this case, no matter which of the key buttons 7 is pressed, all the LEDs 11 are lit simultaneously. This lighting is performed for a predetermined period of time. The fixed time is up when there is no next key operation even after the set time has elapsed since the last operation of the key, and all the LEDs 11 are turned off all at once. When the key button 7 is released, since the metal dome contact 10 and the light diffusion sheet 9 have a restoring force, the shape returns to the original dome shape and the switch is turned off.
[0008]
As shown in FIG. 8, light from each of the LEDs 11 is emitted toward a hemispherical region above the position of the LED chip. Among them, the light emitted upward reaches the lower surface of the front case 2 between the key buttons 7, the light emitted obliquely upward reaches the lower surface of the adjacent key button 7, and further emitted in the horizontal direction. The light reaches the periphery of the light diffusion sheet 9 and is diffused by the light diffusion sheet 9 and enters the key button 7 immediately above. As described above, the key button 7 is illuminated with the direct light from the LED 11 and the diffused light from the light diffusion sheet 9, so that the light from the LED 11 can be used for illuminating the key without waste. Only by pressing one of the key buttons 7, the printing surface 7a on the back of the key is illuminated with light from the LED 11, so that each of the key buttons 7 appears to glow in the dark, and even in a place without a streetlight, Key operations can be performed without difficulty.
[0009]
[Problems to be solved by the invention]
However, according to the conventional key button illuminating device, even if the light diffusion sheet 9 is provided, the direct light from the LED 11 mainly contributes to the illumination of the key button 7. In some cases, causing uneven illumination of the key buttons 7.
[0010]
An object of the present invention is to provide a key button illuminating device in which an operation section of a key button is brightly and uniformly illuminated, and a portable electronic device using the same.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has, as a first feature, a key button illumination device for illuminating a transparent or translucent operation key provided in a portable electronic device, wherein the operation key to be pressed is operated. A key arrangement member arranged in the opening, and a light source for irradiating the key arrangement member from the back surface, wherein the key arrangement member has a diffusion surface for diffusing irradiation light from the light source on the back surface. Key button lighting device.
[0012]
Furthermore, in order to achieve the above object, the present invention has, as a second feature, a battery-powered operation and outdoor use, and a transparent or translucent operation provided in an operation unit. In a portable electronic device including a key button illumination device for illuminating a key from a back surface of the operation unit with a light source disposed in a housing, a key arrangement member in which the operation key is arranged in an opening of the operation unit, A light source for irradiating the key arrangement member from the back surface, wherein the key arrangement member has a diffusion surface on the back surface for diffusing irradiation light from the light source.
[0013]
According to the key button illumination device and the portable electronic device described above, the diffusion surface formed on the back surface of the key arrangement member diffuses light from the light source toward the operation keys, and has not been conventionally used for key illumination. Light can be used, and the operation keys can be uniformly illuminated and brighter.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1A and 1B show the configuration of a main part of a portable electronic device according to the present invention, wherein FIG. 1A shows the front of the front case of the portable electronic device, FIG. 1B shows the side, and FIG. In the following, the same reference numerals are used for the same components as those shown in FIGS. The mobile electronic device 1 is assumed to be a mobile phone.
[0015]
As in FIG. 5, the mobile electronic device 1 has a housing composed of a front case and a rear case, but here only the front case 2 is shown. As shown in FIG. 1A, the front case 2 is provided with an opening 2a for a key button 7 and an opening 2b for a liquid crystal display. Further, a light diffusion sheet 13 is provided on the inner surface (back surface) of the key operation unit of the front case 2 so as to cover a portion excluding the opening 2a as shown in FIG. Further, four screw holes 2c for fixing the rear case (the same as the rear case 3 in FIG. 5) by screwing are formed on the back surface of the front case 2.
[0016]
FIG. 2 shows a cross section of a key operation unit of the portable electronic device according to the embodiment of the present invention. The sectional position is the same as that in FIG. In the front case 2, a key button 7, a rubber sheet 8, a light diffusion sheet 9, a metal dome contact 10, an LED 11, and a substrate 12 are provided. The arrangement structure is the same as that of FIG.
[0017]
In this portable electronic device 1, a light diffusion sheet 13 is attached to a back surface of a front case 2. The light diffusion sheet 13 is processed so that the surface facing the LED 11 can diffuse incident light. As the light diffusion sheet 13, for example, an aluminum foil with an adhesive subjected to a diffusion treatment, a thin metal or resin sheet having a diffusion surface, an adhesive tape or a paper tape having a diffusion film, or the like may be used. it can.
[0018]
FIG. 3 is an enlarged view of a portion b in FIG. In FIG. 3, as described with reference to FIG. 8, of the light from each of the LEDs 11, the light emitted obliquely upward reaches the lower surface of the adjacent key button 7 as direct light, and further emitted in the horizontal direction. The light reaches the periphery of the light diffusion sheet 9, and the light diffused by the light diffusion sheet 9 enters the key button 7 directly above. In addition to such light, in the configuration of FIGS. 1 to 3, the light diffused by the light diffusion sheet 13 enters the key button 7 via the rubber sheet 8 (partly without passing through the rubber sheet 8. Directly from the light diffusion sheet 13 to the bottom of the key button 7).
[0019]
That is, since the light diffusion sheet 13 is provided at each opposing position of the LED 11, the light emitted right above the LED 11 is diffused by the light diffusion sheet 13 and enters the rubber sheet 8, and furthermore, the rubber sheet 8 The light propagates through the inside 8 and reaches the key button 7. A part of the light diffused by the light diffusion sheet 13 directly enters the flange of the key button 7 and illuminates the key button 7. Therefore, light that has not been conventionally used for illuminating the key buttons 7 because of being blocked by the front case 2 can effectively enter the key buttons 7. As a result, the amount of light incident on the key buttons 7 is increased as compared with the conventional configuration in which only the light diffusion sheet 9 is provided, and the key buttons 7 are illuminated uniformly and brightly. In addition, if the same light amount as in the related art is sufficient, the number of LEDs 11 can be reduced, and power consumption, weight, and cost can be reduced.
[0020]
FIG. 4 shows another embodiment of the portable electronic device according to the present invention. In FIG. 4, the same reference numerals are used for the same components as those shown in FIG.
In the configuration of FIGS. 1 to 3, the light diffusion sheet 13 is present as one component, but in the present embodiment, a metal such as aluminum is vapor-deposited in the region of the operation unit on the back surface of the front case 2 to form the vapor deposition surface 14. Is used as the light diffusion sheet 13. The vapor deposition surface 14 has a glossy surface formed by metal vapor deposition. As described with reference to FIG. 3, the light incident on the vapor deposition surface 14 from the LED 11 is diffused or reflected on the rubber sheet 8, and the light diffused on the rubber sheet 8 is a key. Light enters the button 7.
[0021]
By providing the vapor deposition surface 14 in this manner, the same effect as when the light diffusion sheet 13 is adhered to the front case 2 can be obtained, and the key buttons 7 can be uniformly and brightly illuminated. In addition, since there is no need to separately provide the light diffusion sheet 13, the thickness, weight, and cost of the portable electronic device 1 can be reduced. In addition, if the same light amount as in the related art is sufficient, the number of LEDs 11 can be reduced, and power consumption, weight, and cost can be reduced.
[0022]
In the above embodiment, the light diffusion sheet 13 or the vapor-deposited surface 14 is applied to a portable electronic device. However, the present invention is also applicable to key button illumination of an electronic device having a key button other than the portable electronic device.
[0023]
Further, in the above embodiment, the switch mechanism is configured by a combination of the convex portion 8a of the rubber sheet 8, the light diffusion sheet 9, and the metal dome contact 10, but the switch mechanism is not limited to this structure. Any configuration may be used as long as it is turned on / off by pressing 7.
[0024]
Furthermore, in the above-described embodiment, the key buttons 7 and the light diffusion sheet 13 are provided on the front case 2, but they may be provided on the rear case. Although the rubber sheet 8 is a single sheet, it may be provided for each metal dome contact 10 (or for each key button 7).
[0025]
Further, in the above embodiment, the LED is used as the light source, but the present invention is not limited to the LED, and other electro-optical conversion elements, for example, a small incandescent light bulb, an electroluminescence (EL) display It is also possible to use a cold cathode tube or the like.
[0026]
【The invention's effect】
As is clear from the above, according to the key button illuminating device of the present invention and the portable electronic device using the same, the configuration in which the diffusion surface is provided on the back surface of the key arranging member allows the key arranging member near the key button to be provided. It is possible to make light from the light source incident toward the operation key incident on the operation key. Therefore, light that has not been conventionally used for key illumination can be used in the present invention, and the operation keys are uniformly illuminated and illuminated more brightly. If the same amount of light as in the related art is sufficient, the number of elements such as LEDs can be reduced, and low power consumption, light weight, and cost reduction can be achieved.
[Brief description of the drawings]
FIGS. 1A and 1B show a configuration of a main part of a portable electronic device according to the present invention, wherein FIG. 1A is a front view of a front case of the portable electronic device, FIG. 1B is a side view, and FIG.
FIG. 2 is a cross-sectional view showing a cross section of a key operation unit of the portable electronic device according to the embodiment of the present invention.
FIG. 3 is an enlarged cross-sectional view illustrating a portion “b” of FIG. 2;
4A and 4B show a front case in another embodiment of the portable electronic device according to the present invention, wherein FIG. 4A is a front view, FIG. 4B is a side view, and FIG.
5A and 5B show the appearance of the portable electronic device, wherein FIG. 5A is a front view, FIG. 5B is a side view, and FIG. 5C is a rear view.
FIG. 6 is a rear view showing the rear surface of the front case of FIG. 5;
7 shows a conventional key button illumination device, and is a cross-sectional view taken along the line AA in FIG. 5 (a).
FIG. 8 is an enlarged sectional view of a part a of FIG. 7;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Portable electronic device 2 Front case 2a, 2b Opening 2c Screw hole 3 Rear case 4a-4d Screw 5 Display part 6 Key operation part 7 Key button 7a Printing surface 8 Rubber sheet 8a Convex part 9, 13 Light diffusion sheet 10 Metal dome contact 11 LED
12 substrate 14 evaporation surface 61, 62 opening 63 screw hole

Claims (10)

In a key button illuminating device for illuminating a transparent or translucent operation key provided in a portable electronic device,
A key arrangement member in which the operation key to be pressed is arranged in the opening;
Light source for irradiating the key arrangement member from the back surface,
The key button illuminating device, wherein the key disposing member has a diffusion surface on a back surface for diffusing irradiation light from the light source. The key button illumination device according to claim 1, wherein the key arrangement member forms the diffusion surface by attaching a light diffusion sheet that diffuses incident light to a back surface of the key arrangement member. 2. The key button lighting device according to claim 1, wherein the diffusion surface is formed by a metal deposition surface provided on a back surface of the key arrangement member. 3. The key button lighting device according to claim 1, wherein the light source is an electro-optical conversion element such as an LED (light emitting diode). Operation using a battery as a power source and outdoor use are possible, and a transparent or translucent operation key provided on the operation unit is pressed from the back of the operation unit in response to pressing of the operation key at power-on. In a portable electronic device provided with a means for illuminating,
A key arrangement member in which the operation keys are arranged in an opening of the operation unit,
Light source for irradiating the key arrangement member from the back surface,
The portable electronic device according to claim 1, wherein the key arrangement member has a diffusion surface on a back surface for diffusing irradiation light from the light source. 6. The portable electronic device according to claim 5, wherein the key arrangement member forms the diffusion surface by attaching a light diffusion sheet for diffusing incident light to a back surface of the key arrangement member. 6. The portable electronic device according to claim 5, wherein the key placement member forms the diffusion surface by a metal deposition surface provided on a back surface thereof. The portable electronic device according to claim 5, wherein the key arrangement member is a front case forming a part of a housing. 6. The portable electronic device according to claim 5, wherein the operation unit has a plurality of numeric keys and symbol keys arranged in a matrix, and a plurality of the light sources are arranged between the keys. The portable electronic device according to claim 5, wherein the light source is an electro-optical conversion element such as an LED (light emitting diode).

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