1. Field of the Invention
The present invention relates a user input device for small, portable electronics that permits multiple functions to be implemented in a confined space using key images defined by a reconfigurable backlight structure under automatic software control.
2. Description of the Related Art
The consumer electronics industry faces the continuing trends of adding more functionality to consumer devices while at the same time enabling these devices to be physically smaller through the benefits of semiconductor integration. These industry trends, more functionality in a smaller size, have lead to undesirable compromises in keypad design; large keypad areas with an increasing number of very small keys. In many cases the physical size of keys has become too small to be useful for the average user. Purchase decisions are increasingly driven by “ease of use” with larger keys playing an ever increasing role in this decision.
U.S. Pat. No. 4,746,919 to Reitmeier for “Remote control system with key function display provisions” issued May 24, 1988 describes a transmitter unit of a remote control system that includes a key function display unit for identifying the function of key elements of the transmitter unit at various steps of a control sequence for one or more controlled devices. The memory for storing character-representative information for identifying the functions of the key elements of the transmitter and corresponding function control instructions is contained in the controlled devices rather than in the transmitter unit, which allows for the addition of new controlled device without modification of the transmitter units. It is known to utilize electroluminescent (EL) display segments in remote control devices and the like for controlling the operation of various appliances, for example U.S. Pat. No. 7,013,434 to Masters et al. for “Remote control with local, screen-guided setup” issued Mar. 14, 2006 relates to a universal remote control having an EL display where various segments of the EL display are illuminated under user control at various times to present the user with a remote control user interface that corresponds to an activity currently being performed by the user. While EL displays and backlights are well-known in the consumer electronics industry, with EL backlights being very common in cellular telephones in particular, a need exists to provide improved user input devices in keypad device operation and the like.
The present invention relates to user input devices in general and, in particular, keypads in which the image of each key is created using an electroluminescent (EL) panel.
It is a general object of the invention to provide an improved reconfigurable keypad method in a handset device having a display on its housing with the handset device being operable with a plurality of subsystems, which avoids the disadvantages of the prior art while affording additional operating advantages.
To this end, a reconfigurable keypad as the user input device of a cellular telephone, remote control or other consumer electronics application. The goal is to create multiple keypad configurations with the minimum number of large keys. In previous implementations this added functionality is provided by adding keys to a conventional keypad, making the product less user friendly as additional keys are added. This invention eliminates this problem.
For the case of a cellular telephone of the current implementation, three operating modes have been identified:
1. Telephone dialing, using a conventional 3×4 grid of keys,
2. Navigation Mode in which menus or lists need to be quickly reviewed with a particular item being highlighted in the list, then selected,
3. Media player in which additional functions such as Play/Pause, Fast Forward and Rewind are implemented as dedicated keys.
These operating modes enable multiple functions of the device, including
1. telephone
2. camera with zoom in/out, shutter
3. game controller
4. music player
5. video player
The operating modes can be implemented with a minimum of 12 key locations. Each key location includes a popple, a metal dome that provides mechanical feedback and acts as an electrical switch to indicate when a key is depressed by the user. A segmented EL panel covers the popples. The EL panel contains multiple patterns which form the user-perceived key functions. Each pattern can define an entire operating mode by including all necessary images required by the mode, or it may contain only a subset of the images required. Each pattern is also an electrical circuit that links all images together. By linking all images electrically, the complexity and cost of the drive circuit is reduced.
The multiple operating modes of the reconfigurable keypad are under software control. As the user operates the device, the software determines which of the multiple operating modes are appropriate at any given time. The software then commands one or more of the electrical circuits to be energized, illuminating the appropriate key images. The operating software interprets the key depressions based on the operating mode and reacts accordingly. By placing the illumination of the key images and the interpretation of the key depressions under software control, it is possible to dynamically change the keypad as the user is operating the device. The device appears to “anticipate” the user's next move, creating a more enjoyable, less confusing user experience.
Additional features of the invention will become apparent herein, including the reconfigurable keypad in a handset device operable with display, cellular telephone and media player subsystems.
The descriptions illustrate embodiments thereof, from which the inventions, structure, construction and operation, and many related advantages may be readily understood and appreciated.
The following description is provided to enable those skilled in the art to make and use the described embodiments set forth in the best modes contemplated for carrying out the invention. Various modifications, however, will remain readily apparent to those skilled in the art. Any and all such modifications, equivalents, and alternatives are intended to fall within the spirit and scope of the present invention. Referring to Flowchart and Drawings Sheets
A user input device 10, as shown in
The reconfigurable keypad 12 is constructed of several layers of materials used to provide mechanical protection, key depression, and the EL panel 16 itself as shown in
The top (outermost) layer 18 is a protective, transparent plastic film that the user's finger presses on. This must be durable and resistant to water and oil in order to protect the electrical circuitry or the information processor 14 beneath it, but must also be transparent so the key images can be easily seen by the user. In the present embodiment, the outer housing 16 is tinted slightly black to further block visibility of any patterns that are not active. If the outer plastic housing 18 was fully transparent, all three of the patterns would be visible all the time, regardless of whether they were electrically active or not. Tinting of the plastic housing 18 is critical for an aesthetically pleasing appearance.
The EL panel 16 is a thin, flexible polymer sheet that contains multiple patterns for the key images as shown in
The EL panel 16 provides multiple patterns, in this case three patterns, which are used for each operating configuration of the device 10.
The first operating mode shown in
The Navigation Mode requires Up, Down, Left, Right and a center Select (OK) key. In many applications, the center OK label is removed, leaving just a circle for the user to press once the selection is highlighted.
The Telephone Mode provided by the telephone subsystem 26 as seen in
Based on these three configurations, the minimum number of key locations and therefore the minimum number of popples 22 is 12. All three configurations are then overlaid to provide appropriate functionality using only 12 popple 22 locations.
The resulting EL patterns, along with the popple 22 locations are shown in
Popple 22 locations are shown with dashed circles. It should be noted that the popple 22 locations at the 2, 4, 6 and 8 digits are skewed away from the center of the digits in order to provide uniform key depression for all three operating subsystems; telephone keypad 26, navigation 30 and media player 28.
The decision of which of the EL patterns are active at any given time is not explicitly determined by the user. The operating mode of the keypad 12 is automatically determined by the device software, based on the application currently running on the device 10 and/or the application that the software determines will be running next. For instance, while selecting a game from a menu list the software will enable the Navigation Mode of the EL keypad 12. Once the game is running it may dynamically switch between all three modes of keypad operation, depending on the requirements of the game. Another example is when navigating the main menu, the EL keypad 12 will be in Navigation Mode but will automatically change to Media Player Mode if music is selected and a song is playing. Even within the music player subsystem 28, the EL keypad 12 operating mode will automatically change from Media Player Mode to Navigation Mode (subsystem 28 to subsystem 30) if the user moves from listening to a song to browsing the list of albums. This is a completely unique and novel implementation of this functionality.
A significant operational challenge to a light-emitting keypad is the ability to be easily viewed indoors where ambient light is relatively low, as well as in direct sunlight where the incident light from the sun is far more powerful than the EL light source.
In the typical indoor viewing scenario, the light emitted from the EL panel 16 is sufficiently powerful to overcome the ambient light in the room. The user sees only the keypad configuration 12 that is currently active, as described in the previous page.
The other keypad configurations are hidden due to two factors. The other EL patterns are not energized and therefore do not emit light, and the outer plastic housing 18 is only partially transparent.
In the case of outdoor viewing in direct sunlight, the EL panel 16 cannot output more visible energy than the sun. The EL panel 16 is overwhelmed by the sun which makes it impossible to illuminate individual operating modes of the keypad 12. However, we still want the user to be able to locate the key locations so that they can continue to operate the device. This is accomplished through two additional design constraints on the outer plastic housing and the EL panel 16. The first is the outer film 18 must be partially transparent. For best sunlight visibility, the film should be 100% transparent; however, the optimal design criteria for use in both environments are 87% transparent. The second is the default color of the EL panel, i.e. the color when not energized, must be as light as possible, ideally white. A light color is more effective as a reflector of sunlight, which is the desired effect. In the present embodiment, the color is a very light blue.
In the present embodiment, the sunlight is passing through the outer film 18, reflecting off the light blue EL panel 16, and then passing back out through the outer film 18 to the user's eye.
Sunlight viewing is a fully passive mode of operation. The brighter the sunlight, the brighter the keypad image 12 appears to the user. As sunlight becomes less intense, the reflected image becomes dim and the light emitting properties of the EL panel 16 are able to overpower the reflected sunlight, reverting back to the individual images of the keypad 12.
While it is somewhat undesirable for the user to see all operating modes of the keypad, since the user has already experienced the multiple operating modes the user can readily adapt to this environment.
From the foregoing, it can be seen that there has been provided an improved reconfigurable keypad 12 in a handset device 10 operable with display 30, cellular telephone 26 and media player 28 subsystems in a device 10 of simple and economical construction. While a particular embodiment of the present invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects. Therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.
This application claims priority pursuant to 35 U.S.C. 119(e) to U.S. Provisional Application No. 60/916,623, filed on May 8, 2007 which is incorporated herein by reference in its entirety.
Number | Date | Country | |
---|---|---|---|
60916623 | May 2007 | US |