Patent Application
20090135142
The present invention generally relates to electronic devices and more particularly to a method and apparatus for selecting input into an electronic device.
The method of user input to mobile electronic devices is an important element of the user experience. Historically, because of the small physical size of such devices, for example, cell phones, personal digital assistants, pagers, and media players, there is only limited area in which to deploy key input. For example, one common arrangement used for alphanumeric input is the 12 key Bell keypad. When in number entry mode, numbers can be entered with a single keystroke. However, when entering text the user may need to press a key multiple times to select a character. For example, the ABC2 key is pressed twice to select B. Although cumbersome, this is a predominant method of entering text on mobile phones today. An alternative is to make the devices larger so that qwerty keyboards can be used so that only a single keystroke is needed for each key. With the trend in mobile electronic devices towards larger displays, the area for keypads may become more constrained.
In addition to conventional keypads that may employ mechanical dome switches, other types of user input are being deployed on mobile electronic devices. These include touch sensors that detect the presence of a finger by capacitive, optical, resistive, or other physical means. Force or pressure sensors such as force sensitive resistors can be used to supplement touch sensors to discriminate between different levels of force applied to a touch sensor. In addition, haptic feedback is often used in conjunction with such devices to provide user feedback to confirm a keypress when such touch interfaces are used.
Accordingly, it is desirable to leverage these newer user interface technologies to overcome the limited area available on the surface of mobile devices to provide a better user input experience. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.
Embodiments of the present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and
The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.
An apparatus and method described herein integrates, in three embodiments, time, location, and pressure sensing with haptic feedback to simplify the physical workload associated with user input on a keypad or touchscreen. The force, or haptic, feedback preferably is similar to that experienced by a user when pressing and releasing a key. Upon pressing down, a first feedback is experienced that may be a click or short vibration, and subsequent events may also result in additional clicks or short vibrations. One exemplary embodiment improves on the known multitap method of data entry. Instead of multiple key presses on a touch input region, such as a key, to select an input possibility, for example, three presses for selecting “C” on the “ABC2” key, a finger presses the key and releases the key after the desired number of haptic clicks is sensed. Releasing the key after the first haptic click results in an “A” being selected. In the case of selecting a “C”, the finger would be pressed continuously against the “ABC2” key, and released upon sensing the third click. Optionally audio feedback may accompany the key selection as well. This audio feedback may be in the form of an audible click or can be a description of the current selection, for example a voice saying the letter “A.” Although the exemplary embodiments described herein refer to text or alphanumeric selection, any character, data, or input command may be selected by this method.
Another exemplary embodiment involves the application of two or more levels of force applied to the key for selection of the appropriate character. For example, application of a lower force on the “ABC2” key would select the “A”, while application of a greater force would select the “B”. Haptic feedback is provided to assist the user in determining the level of the applied force. One example would be to provide a click feedback as the user exceeds each pressure threshold. Another example would be to provide different types of feedback (e.g. different waveforms or amplitudes) for each pressure range.
In another embodiment, the finger is placed on the desired key and an image appears on the screen indicating the desired selections. The first character is highlighted when the finger is pressed against the key. As the finger moves across the keypad, the cursor moves to another character on the screen. The finger is released from the keypad when the desired character is highlighted on the screen. Optionally, haptic feedback is provided each time another character is highlighted, providing additional information to the user about which character is highlighted.
Referring to
Many methods of providing haptic feedback are known that may be used with the methods described herein, including the haptic feedback apparatus described in U.S. patent application Ser. No. 11/590,494, assigned to the Assignor of this application. In that previously filed application, a piezoelectric ceramic element or multiple piezoelectric ceramic elements are directly bonded to the backbone structure of portable devices, for example the metal or plastic chassis of a cell phone. A chassis of a cell phone provides structural rigidity to the phone and serves as a structure plate for the attachment of most phone modules and components. The piezoelectric ceramic elements and an input device, e.g., a morphable user interface, are bonded to opposite sides of the chassis in one exemplary embodiment. Upon application of an electric field, the in-plane shrinkage or expansion of the piezoelectric elements causes localized flexing motion of the chassis and provide tactile feedback at the interface of the input device. The input device is not directly pushed or pulled by separated piezoelectric bender actuators as described in the prior art, but is part of the structure deformed (flexed) by the integrated piezoelectric ceramic elements. The motion of the input device is flexing, rather than an up/down movement by multiple piezoelectric actuators actuating at multiple points. The benefit of the approach is that it does not require precise mechanical alignment of an actuating element with the structure that is being pushed or pulled.
At least one piezoelectric actuator e.g., a piezoelectric bender, is bonded directly to a metal plate abutting the input device for which the haptic feedback is intended. This direct placement provides flextensional bending movement of the input device, and thus provides tactile feedback including true key click like tactile feedback to a user. This displacement of the input device is small, only 1.0 to 30.0 micrometers.
Piezoelectric actuators are uniquely capable of delivering fast, e.g., 1.0 to 10.0 milliseconds, high acceleration, e.g., 1-100 g, response needed to simulate key click responses. Piezoelectric actuators are also able to provide a broadband movement (1-2000 Hz) as opposed to fixed frequency response of resonant electromagnetic vibration motors.
The piezoelectric elements shrink or expand in the lateral direction when subject to an electric field, causing a much amplified perpendicular movement in its center with the constraint from being bonded to a hard surface, such as a phone chassis. The piezoelectric elements can be driven by a wide range of waveforms to tailor mechanical output to the user. A high slew rate step function can provide the highest acceleration and click-like feedback. Alternatively, multiple sine-waves can be used to generate feedback that might characterized as a buzz. Piezoelectric actuators can also be operated in a wide frequency range, allowing broadband haptic responses. Power consumption of piezoelectric actuators is generally comparable to or less than that of DC rotary motors. The actuators' latency (the time required to ramp up to full speed) is small enough to allow users to have nearly instantaneous response in interactive applications.
While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims.
