Emerging Force Touch Sensing Technologies Insights from Patents

Alex G. Lee (alexglee@techipm.com)

https://www.linkedin.com/today/author/2853055

Touch sensor devices are widely used in a variety of electronic devices (e.g., smartphones, wearable devices, PCs).

Touch sensor devices utilize sensors based on capacitive, resistive, inductive, optical, acoustic or other

technologies. Recently, touch sensor devices are implementing with additional ability to detect and determine force

applied to a surface of the sensor. This force information can be used to control operations of the electronic devices

to provide a much richer scope of user experience (UX).

US20150138112 illustrates the MEMs force sensor module for the touch-sensitive electronic devices. The MEMs

force sensor module enables mass producing MEMS force sensor devices for wearable devices by solving a

number of engineering challenges with MEMS based touch technologies. The touch-sensitive electronic device

includes a touch screen and a force sensor module that is adhered to the touch screen. The touch screen can has a

touch surface and a rear surface opposite to the touch surface. The force sensor module includes several force

sensors, a bias assembly and an opposing bias assembly. The bias assembly has a top wall and several side walls

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extending from the top wall. The top and defines a chamber. The force sensors are arranged between the bias

assembly and the opposing bias assembly within the chamber.

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US20150220197 illustrates the 3D force sensor that is able to simultaneously sense the magnitude of a force and

the 3D tilting angle of the force when touching the force sensor. The 3D force sensor can detect its orientation and

the magnitude and 3D direction of a force applied to its surface. The force can be non-parallel and non-orthogonal

to the surface of the 3D force sensor. Several 3D force sensors are simultaneously used to detect the orientation of

an object and the magnitude and 3D direction of the forces applied to the object. Several 3D force sensors also can

be used to detect the tilting of a vertical or horizontal stacking of the objects relative to one another. Measurement

of the 3D tilting angle of the force when the force is non-parallel and non-orthogonal to the surface can be used in

many electronic device applications. For example, in a gaming application, if the magnitude of a force represents a

speed of a movement, the 3D titling angle of the force can represent the direction of the movement in three-

dimensions on the computer display.

US20150242037 illustrates a touch sensor that is able to determine the magnitude or degree of force associated

with a touch. The estimated magnitude or degree of the force can be used as an input signal to the electronic

device. This permits multiple different inputs through a single touch input device, such that the response or output

of the device varies with the input force. Accordingly, the first force exerted on a given point can be interpreted as

the first input type or command, while the second force (different in amount from the first) at the same point can be

interpreted as the second input type or command. Thus, the device's responses or outputs are differ in response to

the two inputs, even though they occur at the same point and use the same input device. The touch sensor uses a

transparent force-sensitive film having strain-relief features.©2015 TechIPm, LLC All Rights Reserved http://www.techipm.com/

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