In today’s world, almost all user interfaces are based on touch. The modern touch screen applications are based on dependent on touch sensor technology. From smartphones, tablets, elevators, ATMs, cameras, laptops, etc. Mouse, switches, and keypads are now being replaced by touch-sensitive technology. It is a more intuitive user interface technology that more reliable and convenient. Besides, it gives the devices a more appealing and contemporary look.
Touch sensors can also be referred to as tactile sensors as they are sensitive to pressure, force, or touch. The touch sensors can be capacitive or resistive touch sensor. Let’s look at the two without all the tech lingo surrounding these terms for easy comprehension.
Capacitive Touch Sensors
Capacitive touch interfaces are commonly found in most portable devices like smartphones and remotes. Home appliances, industrial applications, and automotive also use capacitive touch. This is because the cost of production is more affordable not forgetting they are more durable, robust, and have a captivating product design. Unlike their mechanical counterparts, touch sensors don’t have moving parts. Additionally, they have no opening for dust and humidity to enter hence their durability and robustness.
In capacitive touch sensors, the presence of conductive material is needed to trigger the load without applying any force to it. Therefore, getting false or unintentional triggers is a likely occurrence. Especially when there is moisture or water which are good conductors of electricity. However, a lot of effort has been put into distinguishing between false and intentional triggers. From additional sensing pads to getting rid of reference ground electrode, and software algorithms.
Also, capacitive touch sensors come in two types, projected and surface capacitive sensing. The projected capacitive sensor acts on near proximity sensing so the finger doesn’t have to come into contact with the conductive material. On the other hand, surface capacitive sensing responds to human contact on the conductive material for an action to be carried out.
Resistive Touch Sensor
These are simple control circuits used for a longer time than capacitive touch sensors. They aren’t dependent on a conductive material as they accommodate non-conducting materials such as gloves, pens, or stylus. A resistive touch sensor relies on the pressure on a surface for it to respond. It is made up of two conductive layers (film/glass at the bottom and film at the top) separated by small spacer dots. Whenever pressure is applied to the top film, the sensor is activated. These sensors are commonly used in harsh environments.