Optical sensing mechanisms for input devices

#The present invention relates generally to electronic devices and more specifically, to sensing user inputs through an input device for electronic devices.

#Electronic devices, such as laptop computers, may include one or more input devices, such as track pads that may be used to receive one or more user inputs. These type of input devices may allow a user to provide one or more commands by providing an input to a particular surface. For example, track pads generally have a input surface and a user may drag his or her fingers across the input surface to vary the location of a cursor across a display. These type of input devices may also include one or more buttons or may themselves act as a button and mechanically depress. Selection or the buttons or by depressing the surface itself, these type or track pads may be used to provide a different type of input to the electronic devices. However, many current input devices, especially those such as track pads, may be limited in the number and type of inputs they can receive. The limitations may be based on the number of parameters the input devices may be configured to detect.

#An input device for providing inputs to an electronic device. The input device includes a user input surface movably connected to a substrate, at least one light sensor operably connected to one of the user input surface or the substrate, and a light source in selective communication with the at least one light sensor. When the user input surface is in a first position the at least one light sensor receives a first value of light from the light source and when the user input surface is in a second position the at least one light sensor receives a second value of light from the light source.

#FIG. 1 is a perspective view of an electronic device incorporating a track pad in accordance with the present disclosure.

#FIG. 2 is a simplified block diagram of the electronic device of FIG. 1.

#FIG. 3A is an enlarged top plan view of the track pad of FIG. 1.

#Some embodiments described herein may take the form of optical sensing mechanisms for sensing inputs to a track pad or other input device. The various optical sensing mechanisms may detect displacement (vertical, lateral, and/or angular) of a surface, which may be correlated to one or more user inputs. The detected displacement may be provided to an electronic device incorporating or otherwise in communication with the track pad. In addition to determining displacement, which may be correlated to a magnitude of the force input, the optical sensing mechanisms may also detect the velocity, force, input or click acceleration, pressure, and other various parameters of the user inputs. Because the optical sensing mechanisms can detect a variety of parameters, the track pad may be used to provide a number of different inputs to the computing device. For example, the user may use finger gestures to provide certain commands to the computing device, varying force velocities or pressures may be used to provide different inputs, or the like.

#In one embodiment, the optical sensing mechanisms may include a light source, such as a light emitting diode (LED) and two or more optical sensors. In this embodiment, the track pad may include one or more light blocking components, such as baffles, operably connected to a user input surface, and as the track pad moves in response to a user input, the light blocking components may selectively alter the light received at the two or more optical sensors from the light source. By using two or more sensors one or more processors may correlate the light received at each sensor with the movement of the track pad and determine the input force from the movement.

#In some instances, the track pad may further include a beam splitter, such as a prism, and one or more reflecting components such as mirrors that are in optical communication with the beam splitter. In these instances, the beam splitter may divert light from the light source, which may be reflected to the optical sensors by the one or more reflecting components. As the user input surface moves, the light blocking components may selectively block light from the one or more light reflecting elements from reaching the light sensors.