How Touchscreens Work
Whether we realize it or not,
touchscreens have taken over many different aspects of our life and have
changed how we interact with machines. We use them on a daily basis and they
are used in many ways besides on your phone or tablet. Signed your name for a
credit card transaction? That’s a touchscreen. Touchscreens are being
implemented in many devices we interact with like printers, cameras, ATMs, and
even soda machines. So how does this technology work?
There are many kinds of touchscreen technologies but only two kinds that are widely used: resistive and capacitive. Resistive touch screens work by sensing the pressure of an input using two panels stacked on top of one another. The top layer (the one we touch) is flexible and the bottom layer is not. When we touch a resistive touchscreen the top panel bends due to the force of the touch and touches the rigid layer. This completes a circuit in the system and from that input the screen is able to detect where the screen was touched.
The most commonly used
touchscreen technology is capacitive. This is what is used in our smartphones,
tablets, and hybrid laptops. Capacitive screens are more precise than resistive
screens which is why they are preferred for devices we interact with often. These
screens have very tiny conductive wires embedded throughout the screen. When a
finger touches the screen sensors in the corners of the screen send an electrical
charge into the finger which drops the voltage in that part of the screen. The
device then uses this information to deduce where your finger is on the screen
and what to do with that input. On a side note this is also why our phones don’t
work when we wear gloves. The material of the glove doesn’t conduct electricity
like our skin and so the circuit cannot be completed. Almost everyone today uses touch screens to interact with our devices and they have changed the
way we interact with not only our phones, but many other pieces of technology
around us.
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