Luminous keyboard

A luminous keyboard includes plural keys, a membrane switch circuit member, a supporting plate and a backlight module. The membrane switch circuit member is located under the plural keys, and includes an upper wiring plate, a lower wiring plate and a separation plate. The supporting plate is located under the membrane switch circuit member and connected with the plural keys. The backlight module is located under the supporting plate to generate a light beam. A periphery region of at least one of the upper wiring plate, the lower wiring plate and the separation plate is bent to cover the supporting plate and the backlight module. Consequently, the light beam is not leaked out through the periphery region of the backlight module.

FIELD OF THE INVENTION

The present invention relates to a keyboard, and more particularly to a luminous keyboard with an illuminating function.

BACKGROUND OF THE INVENTION

Generally, the widely-used peripheral input device of a computer system includes for example a mouse device, a keyboard, a trackball device, or the like. Via the keyboard, characters and symbols can be inputted into the computer system directly. As a consequence, most users and most manufacturers of input devices pay much attention to the development of keyboards.

FIG. 1is a schematic top view illustrating the outer appearance of a conventional keyboard. As shown inFIG. 1, there are plural keys10on a surface of the conventional keyboard1. These keys10are classified into several types, e.g. ordinary keys101, numeric keys102and function keys103. When one of these keys10is depressed by the user's finger, a corresponding signal is issued to the computer, and thus the computer executes a function corresponding to the depressed key. For example, when an ordinary key101is depressed, a corresponding English letter or symbol is inputted into the computer. When a numeric key102is depressed, a corresponding number is inputted into the computer. In addition, the function keys103(F1˜F12) can be programmed to provide various functions. For example, the conventional keyboard1is a keyboard for a notebook computer.

With the maturity of the computing technologies, the keyboard manufacturers make efforts in designing novel keyboards with special functions in order to meet diversified requirements of different users. For this reason, luminous keyboards are favored by users. The outer appearance of the conventional luminous keyboard is substantially similar to the outer appearance of the conventional keyboard1. Since the luminous keyboard provides the function of illuminating the keys, the inner structure of the luminous keyboard is different from the inner structure of the keyboard without the illuminating function. Hereinafter, the inner structure of the luminous keyboard will be illustrated in more details.FIG. 2is a schematic cross-sectional view illustrating a conventional luminous keyboard. As shown inFIG. 2, the conventional luminous keyboard2comprises plural keys20, a membrane switch circuit member21, a supporting plate22and a backlight module23. Each key20comprises a keycap201, a scissors-type connecting element202and an elastic element203. In the key20, the keycap201is exposed outside the conventional luminous keyboard2, so that the keycap201can be depressed by the user. The scissors-type connecting element202is used for connecting the keycap201and the supporting plate22. The elastic element203is penetrated through the scissors-type connecting element202. In addition, both ends of the elastic element203are contacted with the keycap201and the membrane switch circuit member21, respectively. The supporting plate22is located under the membrane switch circuit member21. The keycap201, the scissors-type connecting element202, the elastic element203and the membrane switch circuit member21are supported on the supporting plate22.

The membrane switch circuit member21comprises an upper wiring board211, a separation layer212, and a lower wiring board213. The upper wiring board211, the separation layer212and the lower wiring board213are all made of a light-transmissible material. The light-transmissible material is for example polycarbonate (PC) or polyethylene (PE). The upper wiring board211has plural upper contacts2111. The separation layer212is located under the upper wiring board211, and comprises plural perforations2121corresponding to the plural upper contacts2111. The lower wiring board213is located under the separation layer212, and comprises plural lower contacts2131corresponding to the plural upper contacts2111. The plural lower contacts2131and the plural upper contacts2111are collectively defined as plural key switches214.

The backlight module23comprises a light guide plate230, a circuit board231, plural light-emitting elements232, a reflecting plate233and a light-sheltering plate234. For clarification and brevity, only two light-emitting elements232are shown in the drawing. The light guide plate230is located under the supporting plate22. The circuit board231is located under the membrane switch circuit member21and electrically connected with the light-emitting elements232. The circuit board231provides electric power to the plural light-emitting elements232. The plural light-emitting elements232are disposed on the circuit board231. In addition, the plural light-emitting elements232are inserted into plural reflecting plate openings2331of the reflecting plate233and plural light guide plate openings2301of the light guide plate230, respectively. By acquiring the electric power, the plural light-emitting elements232are driven to emit plural light beams B. Moreover, the plural light beams B are introduced into the light guide plate230. After portions of the light beams B are exited from the light guide plate230, the light beams B are reflected back into the light guide plate320by the reflecting plate233. The light-sheltering plate234is located over the light guide plate230for sheltering the light beams B. For example, the plural light-emitting elements232are side-view light emitting diodes. After the light beams B are introduced into the light guide plate230, the light beams B are subjected to total internal reflection within the light guide plate230. Then, the light beams B are guided to the keycap201by the light guide plate230.

From top to bottom, the keycap201, the scissors-type connecting element202, the elastic element203, the membrane switch circuit member21, the supporting plate22, the light-sheltering plate234, the light guide plate230and the reflecting plate233of the conventional luminous keyboard2are sequentially shown. For example, the conventional luminous keyboard2is a keyboard for a notebook computer (not shown).

In the conventional luminous keyboard2, each keycap201has a light-outputting zone2011. The light-outputting zone2011is located at a character region or a symbol region of the keycap201. Moreover, the position of the light-outputting zone2011is aligned with the position of a corresponding light-guiding dot2302of the light guide plate230. The light beams can be guided upwardly to the light-outputting zone2011by the corresponding light-guiding dot2302. The light-sheltering plate234comprises plural light-sheltering plate openings2341. The plural light-sheltering plate openings2341are aligned with the corresponding light-guiding dots2302and the corresponding light-outputting zones2011. Consequently, the light beams B are transmitted through the light-sheltering plate openings2341of the light-sheltering plate234. Similarly, the supporting plate22comprises plural supporting plate openings221. The plural supporting plate openings221are aligned with the corresponding light-guiding dots2302and the corresponding light-outputting zones2011. Consequently, the light beams B are transmitted through the supporting plate openings221of the supporting plate22.

On the other hand, since the membrane switch circuit member21is made of the light-transmissible material, the plural light beams B can be transmitted through the membrane switch circuit member21. Consequently, after the plural light beams B are guided by the light-guiding dots2302, the plural light beams B are sequentially transmitted through the plural supporting plate openings221and the membrane switch circuit member21and directed to the plural light-outputting zones2011, thereby illuminating the character region or the symbol region of the keycap201. Under this circumstance, the illuminating function is achieved.

Please refer toFIG. 2again. For sealing the light guide plate230, the lateral edges2332of the reflecting plate233have to be attached on the light-sheltering plate234. Consequently, the light beams B are not leaked from the lateral edges of the light guide plate230. That is, the problem of causing light leakage will be eliminated. Since the lateral edge2332of the reflecting plate233is attached on the light-sheltering plate234, the attaching structure between the lateral edges2332of the reflecting plate233and the light-sheltering plate234occupies a space, it is difficult to reduce the volume of the luminous keyboard.

Therefore, there is a need of providing a luminous keyboard with reduced volume and capable of solving the lateral light leakage problem.

SUMMARY OF THE INVENTION

An object of the present invention provides a luminous keyboard with reduced volume and capable of solving the lateral light leakage problem.

In accordance with an aspect of the present invention, there is provided a luminous keyboard. The luminous keyboard includes at least one key, a membrane switch circuit member, a supporting plate and a backlight module. The at least one key is exposed outside the luminous keyboard. The membrane switch circuit member is located under the at least one key, and includes an upper wiring plate, a lower wiring plate and a separation plate. When the membrane switch circuit member is triggered by the at least one key, a corresponding key signal is generated. The upper wiring plate is contacted with the at least one key. The lower wiring plate is located under the upper wiring plate. The separation layer is arranged between the upper wiring plate and the lower wiring plate. The upper wiring plate and the lower wiring plate are separated from each other by the separation layer. The supporting plate is located under the membrane switch circuit member and connected with the at least one key. The backlight module is located under the supporting plate. The backlight module generates a light beam and projects the light beam to the at least one key. A periphery region of at least one of the upper wiring plate, the lower wiring plate and the separation plate is extended over the supporting plate and bent to cover a periphery region of the supporting plate and a periphery region of the backlight module. Consequently, the light beam is not leaked out through the periphery region of the backlight module.

From the above descriptions, the present invention provides the luminous keyboard. The periphery region of the at least one of the upper wiring plate, the lower wiring plate and the separation layer of the membrane switch circuit member is extended over the supporting plate. The periphery region is bent to cover the periphery region of the supporting plate and the periphery region of the backlight module. Consequently, the light beams are not leaked out through the periphery region of the backlight module. Since the periphery region of the at least one of the upper wiring plate, the lower wiring plate and the separation layer is attached on the lateral edge and the bottom surface of the backlight module, the attaching structure of the conventional technology is omitted. Under this circumstance, the available space within the luminous keyboard is increased. In other words, the volume of the luminous keyboard can be further reduced.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

For overcoming the drawbacks of the conventional technology, the present invention provides a luminous keyboard.

The structure of the luminous keyboard will be described with reference toFIGS. 3 and 4.FIG. 3is a schematic exploded view illustrating a portion of a luminous keyboard according to a first embodiment of the present invention.FIG. 4is a schematic cross-sectional view illustrating a portion of the luminous keyboard according to the first embodiment of the present invention. The luminous keyboard3comprises plural keys30, a membrane switch circuit member31, a supporting plate32and a backlight module33. The plural keys30are exposed outside the luminous keyboard3. The membrane switch circuit member31is located under the plural keys30. When the membrane switch circuit member31is triggered by one of the plural keys30, a corresponding key signal is generated. The supporting plate32is located under the membrane switch circuit member31and connected with the plural keys30. The supporting plate32comprises plural hooks321and plural supporting plate openings322. The backlight module33is located under the supporting plate32. The backlight module33is used for emitting light beams B and projecting the light beams B to the plural keys30.

As shown inFIGS. 3 and 4, each key30comprises a keycap301, a connecting element302and an elastic element303. Each keycap301has a light-outputting zone3011. After the light beams B pass through the light-outputting zone3011, the key31is illuminated. The keycap301is exposed outside the luminous keyboard3, and thus the keycap301can be depressed by the user. The scissors-type connecting element302is used for connecting the keycap301and the hooks321of the supporting plate32. Consequently, the keycap301is moved upwardly or downwardly relative to the supporting plate32. The elastic element303is penetrated through the connecting element302. In addition, both ends of the elastic element303are contacted with the keycap301and the membrane switch circuit member31, respectively. As the keycap301is moved downwardly to push the elastic element303, the membrane switch circuit member31is triggered.

In this embodiment, the connecting element302is a scissors-type connecting element, and the elastic element303is a rubbery elastomer. Preferably but are not exclusively, the plural keycaps301of the plural keys are moved upwardly or downwardly with the connecting elements302, and the membrane switch circuit member31is depressed by the elastic elements303through the connecting elements302. In another embodiment, the connecting elements are non-scissors connecting elements for controlling movements of the keys. For example, a crater-shaped connecting element for a desktop computer is one of the non-scissors connecting elements. In a further embodiment, the keycaps are moved upwardly or downwardly in response to magnetic forces.

The structure of the membrane switch circuit member31will be described as follows. The membrane switch circuit member31comprises an upper wiring plate311, a lower wiring plate312and a separation layer313. The upper wiring plate311is contacted with the elastic elements303of the keys30. The upper wiring board311has plural upper contacts3111. The lower wiring plate312is located under the upper wiring plate311. The lower wiring plate312comprises plural lower contacts3121corresponding to the plural upper contacts3111. The separation layer313is arranged between the upper wiring plate311and the lower wiring plate312. When the key30is not depressed, the upper wiring plate311and the lower wiring plate312are separated from each other by the separation layer313. Consequently, the upper contact3111and the corresponding low contact3121are not erroneously contacted. The separation layer313comprises plural perforations3131corresponding to the plural upper contacts3131. The plural upper contacts3131, the plural lower contacts3121and the plural perforations3131are collectively defined as plural key switches314. When the membrane switch circuit member31is pressed by the elastic element303, the corresponding upper contact3111is inserted into the corresponding perforation3131and contacted with the corresponding lower contact3121. Consequently, the corresponding key signal is generated.

The structure of the backlight module33will be described as follows. The backlight module33comprises a light guide plate331, plural light-emitting elements332, a reflecting plate333and a circuit board334. The light guide plate331is located under the supporting plate32. The light guide plate331is used for guiding the light beams B to the light-outputting zones3011. The light guide plate331comprises plural light guide plate openings3311and plural light-guiding parts (not shown). Each light guide plate opening3311is aligned with one of the plural light-emitting elements332. The light-guiding parts are used for guiding the light beams B to be exited from the light guide plate331and projected to the light-outputting zones3011. The reflecting plate333is located under the light guide plate331. After portions of the light beams B are exited from the light guide plate331, the light beams B are reflected back into the light guide plate331by the reflecting plate333. Consequently, the utilization efficiency of the light beam B is enhanced. The reflecting plate333comprises plural reflecting plate openings3331corresponding to the plural light-emitting elements332. The light-emitting elements332emit the light beams B. In addition, the plural light-emitting elements332are inserted into the corresponding reflecting plate openings3331and the corresponding light guide plate openings3311. Consequently, the light beams B can be introduced into the light guide plate331. The circuit board334is located under the reflecting plate333and electrically connected with the light-emitting elements332. The plural light-emitting elements332are supported on the circuit board334. The circuit board334provides electric power to the plural light-emitting elements332. By acquiring the electric power, the plural light-emitting elements332are driven to emit plural light beams B. In this embodiment, the light-emitting element332is a side-view light emitting diode, the light-guiding part is one of a light-guiding microstructure, a light-guiding dot, a light-guiding ink and a light-guiding texturing structure, and the circuit board334is a flexible printed circuit (FPC).

When the light-emitting elements332are driven to emit the light beams B, the light beams B are introduced into the light guide plate331. The light beams B are guided by the light-guiding parts and exited from the light guide plate331. Then, the light beams B are transmitted through the corresponding supporting plate openings322and the membrane switch circuit member31. Consequently, the light beams B are projected to the light-outputting zones3011of the keycaps301. Moreover, portions of the light beams B are exited from the light guide plate331but not guided by the light-guiding parts. The portions of the light beams B that are exited from the light guide plate331are reflected back into the light guide plate311by the reflecting plate333and further guided to the light-outputting zones3011by the light-guiding parts.

The operations of depressing the keycap301of the luminous keyboard3will be described as follows. Please refer toFIG. 3again. While one of the keycaps301is depressed by the user's finger, the keycap301is moved downwardly. Since the connecting element302is pushed by the keycap301, the connecting element302is correspondingly swung relative to the supporting plate32. Moreover, as the keycap301is moved downwardly to push the elastic element303, the elastic element303is subjected to deformation to trigger the corresponding key switch314of the membrane switch circuit member31. Consequently, the corresponding key signal is generated. When the keycap301is no longer depressed by the user and no external force is exerted on the keycap301, the elastic element303is not pushed by the keycap301. Meanwhile, the elastic element303is restored to its original shape from the deformed state in response to the elasticity of the elastic element303. In addition, the elastic element303provides an upward restoring force to the keycap301. As the keycap301is moved upwardly, the connecting element302is correspondingly swung. Consequently, the keycap301is returned to its original position.

The following three aspects should be specially described. Firstly, a periphery region3112of the upper wiring plate311(i.e., the region circumscribed by dotted lines as shown inFIG. 3) is extended over the lower wiring plate312, the separation layer313, the supporting plate32and the backlight module33. That is, the size of the upper wiring plate311is larger than the size of the lower wiring plate312, the size of the separation layer313, the size of the supporting plate32and the size of the light guide plate331. Consequently, the periphery region3112of the upper wiring plate311is bendable to cover a periphery region323of the supporting plate32, a periphery region3312of the light guide plate331and a periphery region3332of the reflecting plate333.

Secondly, a first light-sheltering structure34as shown inFIG. 3and indicated by dotted lines is formed on the periphery region3112of the upper wiring plate311. For example, the first light-sheltering structure34is produced by printing or spraying a light-sheltering material on the periphery region3112of the upper wiring plate311. Due to the first light-sheltering structure34, the periphery region3112of the upper wiring plate311has the function of sheltering the light beams B. Consequently, the light beams B are not leaked out through the periphery region3312of the light guide plate331.

Thirdly, a second light-sheltering structure35is formed on an inner region3113of the upper wiring plate311. The second light-sheltering structure35is arranged between the plural keycaps301and the backlight module33to shelter the light beams B. Moreover, the second light-sheltering structure35is not aligned with the plural light-outputting zones3011. Consequently, the light beams B can be transmitted through the lower wiring plate312, the separation layer313and the upper wiring plate311and projected to the light-outputting zones3011. Due to the arrangement of the second light-sheltering structure35, it is not necessary to install a light-sheltering plate in the luminous keyboard of the present invention. In an embodiment, the first light-sheltering structure34and the second light-sheltering structure35are produced by printing or spraying light-sheltering ink. It is noted that the position of the second light-sheltering structure is not restricted to the inner region of the upper wiring plate. In another embodiment, the second light-sheltering structure is formed on an inner region of the lower wiring plate or an inner region of the separation layer.

The present invention further comprises a second embodiment, which is distinguished from the first embodiment.FIG. 5is a schematic exploded view illustrating a portion of a luminous keyboard according to a second embodiment of the present invention.FIG. 6is a schematic cross-sectional view illustrating a portion of the luminous keyboard according to the second embodiment of the present invention. As shown inFIGS. 5 and 6, the luminous keyboard4comprises plural keys40, a membrane switch circuit member41, a supporting plate42and a backlight module43. Each key40comprises a keycap401, a connecting element402and an elastic element403. Each keycap401has a light-outputting zone4011. The membrane switch circuit member41comprises an upper wiring plate411, a lower wiring plate412and a separation layer413. The backlight module43comprises a light guide plate431, plural light-emitting elements432, a reflecting plate433, a circuit board434and a light-sheltering plate435. Except for the following two items, the structure of the luminous keyboard4of this embodiment is substantially identical to the structure of the luminous keyboard3of the first embodiment. Firstly, the structure of the membrane switch circuit member41is distinguished. Secondly, the backlight module43further comprises the light-sheltering plate435.

The structure of the membrane switch circuit member41will be described as follows. In this embodiment, a periphery region4122of the lower wiring plate412(i.e., the region circumscribed by dotted lines as shown inFIG. 5) is extended over the upper wiring plate411, the separation layer413, the supporting plate42and the backlight module43. That is, the size of the lower wiring plate412is larger than the size of the upper wiring plate412, the size of the separation layer413, the size of the supporting plate42and the size of the light guide plate431. Consequently, the periphery region4122of the lower wiring plate412is bendable to cover a periphery region423of the supporting plate42and a periphery region4312of the light guide plate431. Moreover, a light-sheltering structure44is formed on the periphery region4122of the lower wiring plate412. For example, the light-sheltering structure44is produced by printing or spraying a light-sheltering material on the periphery region4122of the lower wiring plate412. Due to the light-sheltering structure44, the periphery region4122of the lower wiring plate412has the function of sheltering the light beams B. Consequently, the light beams B are not leaked out through the periphery region4312of the light guide plate431.

The light-sheltering plate435of the backlight module43is arranged between the light guide plate431and the supporting plate42to shelter the light beams B. Consequently, the light beams B are allowed to be projected to the light-outputting zones4011only. The light-sheltering plate435comprises plural light-sheltering plate openings4351corresponding to the light-outputting zones4011. The light beams B are transmitted through the light-sheltering plate openings4351of the light-sheltering plate435and projected to the light-outputting zones4011.

As shown inFIG. 6, the periphery region423of the supporting plate42and the periphery region4312of the light guide plate431are covered by the periphery region4122of the lower wiring plate412, but a periphery region4332of the reflecting plate433is not covered by the periphery region4122of the lower wiring plate412. In this embodiment, a lateral edge4333of the reflecting plate433is covered by the periphery region4122of the lower wiring plate412. That is, the bottom surface of the periphery region4122of the lower wiring plate412and the bottom surface of the reflecting plate433are aligned with each other and located at the same level. Since the thickness of the luminous keyboard4is reduced, the volume of the luminous keyboard4is reduced

In the above embodiments, the periphery region of the upper wiring plate or the periphery region of the lower wiring plate is bent to cover the backlight module. It is noted that numerous modifications may be made while retaining the teachings of the present invention. For example, in another embodiment, the periphery region of the separation layer is bent to cover the backlight module.

From the above descriptions, the present invention provides the luminous keyboard. The periphery region of at least one of the upper wiring plate, the lower wiring plate and the separation layer of the membrane switch circuit member is extended over the supporting plate. The periphery region is bent to cover the periphery region of the supporting plate and the periphery region of the backlight module. Consequently, the light beams are not leaked out through the periphery region of the backlight module. Since the periphery region of the at least one of the upper wiring plate, the lower wiring plate and the separation layer is attached on the lateral edge and the bottom surface of the backlight module, the attaching structure of the conventional technology is omitted. Under this circumstance, the available space within the luminous keyboard is increased. In other words, the volume of the luminous keyboard can be further reduced.