Understanding the Difference between Projected Capacitive Touch and Resistive Touch Panels

As the mobile computing sector experiences an explosion in growth, understanding the touchscreen technology that drives user interfacing is more important than ever. After decades of development, both projected capacitive touch (PCT) panels and resistive touch panels (RTP) are capable of providing precise, reliable input solutions for manufacturers, readily available through P-tec’s products.

What is Projected Capacitive Touch?

PCT technology operates by laying one or more grids of conductive transparent material over glass or another insulator. The grid allows the formation of an electrostatic field that can then be used to track input. When a finger or conductive object comes in contact with the field, it disrupts the electrostatic charge. That disruption is then tracked along X and Y coordinates to determine the point of input. Panels like P-tec’s TFT LCD Display Modules can harness this input to allow precision control of the on-screen interface.

PCT technology can overcome the limitations of prior Capacitive Touch solutions in that it can register input from an object with poor conductance, allowing use with a gloved finger or passive stylus. While it offers higher input resolution than RTP alternatives, it can still suffer from ghosting or muddled tracking if dust or moisture gathers on the panel.

What is Resistive Touch?

RTP technology utilizes two separate layers of conductive material separated by a gap to sense user input. An electric charge is applied to one layer so that pressing on the panel brings the two layers into contact, transferring that charge between them. The point of conductance is then measured along X and Y coordinates to establish the contact location and determine input.

Resistive touch solutions are often cheaper to construct than capacitive alternatives, but can be prone to damage, as the top conductive layer requires a degree of vulnerable flexibility to operate. While RT panels provide relatively poor input resolution, innovations in the technology allow RTP modules like those available at P-tec to overcome this limitation through software and controller advances. They allow more precise control and even multi-touch capabilities. Additionally, the pressure-sensitive nature of the technology allows input from many sources, regardless of their conductive properties.

The Future, Now

As liquid crystal displays become prevalent in devices of every shape and size, the future for PCT and RTP technology at P-tec is promising. Touchscreen input is fueling a paradigm-shifting burst of innovation in electronics design, and it seems increasingly likely that the average consumer will come to rely on these screens in every aspect of their lives in very short order.