Types of Touchscreen Technology
From smartphones to laptops, tablet computers, cash registers and information kiosks, touchscreen technology has become an essential part of everyday life.
Touch screens use different technologies to sense and respond to a touch. The type of touch screen determines what it will detect, how it will respond and whether other objects can be used instead of fingers.
Capacitive
Capacitive touch screens are a type of computer display that uses the conductive properties of a human finger to perform touch commands on a device. Capacitive touchscreen technology has a number of advantages over resistive touch screen technology, including superior image quality and more accurate multi-touch functionality.
A capacitive touchscreen consists of a conductive layer on top of an insulator, such as a glass panel. When a human finger is touched, it creates a small capacitor in the conductive layer. The resulting change in the electrostatic field of the display interface is detected and sent to the controller for processing.
The processor then uses the change in capacitance to determine the location of a finger’s contact. This allows the touchscreen to register any command that a finger makes.
One disadvantage of capacitive technology is that it cannot be used to detect a finger through electrically insulating materials, such as gloves. This disadvantage can be overcome in some cases with a special capacitive stylus or a special-application glove with an embroidered patch of conductive thread allowing electrical contact with the user’s fingertip.
Another advantage of capacitive technology is its low power requirements. This means that a touchscreen can run for longer periods of time than a resistive touchscreen.
In addition, a capacitive screen can be more thin and lightweight than its resistive counterpart. This can be important for mobile devices, especially in situations where space is at a premium.
Projected capacitive touch screens use a grid of horizontal and vertical electrodes on the conductive layer to detect a change in electrostatic charge caused by contact with a bare finger. This change in capacitance is detected using the conductive grid and can be determined by examining the intersections of columns and rows.
Projected capacitive touchscreens can be adapted to work with various types of fingers, and they are often preferred by businesses that need a high level of input accuracy. They also provide a higher resolution and multi-touch capabilities than resistive touch screens.
Resistive
Resistive touch screens are the most common type of touchscreen used in industrial electronics. They’re also inexpensive and durable. These types of screens are commonly found in ATMs, card readers at the grocery store, and older home electronics (like GPS that you purchased in 2006).
The basic structure of resistive touch screens is composed of two layers of material, separated by a thin gap of air. The upper layer is usually made of PET film, while the bottom is typically glass. Both are lined with conducting materials, like indium tin oxide (ITO). The conductors on the top and bottom layers are held apart by dielectric spacer dots. When a finger or stylus is pressed against the screen, the pressure of the touch connects these two layers, creating a change in resistance and triggering the RTP controller.
In addition to a pressure-activated touch sensor, the screen also features an electro-optical array that detects Touch screen and tracks a pixel’s position in both the X and Y planes. The pixel’s position is sent to a microcontroller that uses a simple coding method to determine the correct touch point.
PCAP technology supports a wide range of inputs, including multi-touch functionality, swipes, pinches, and zoom gestures. While these advanced technologies are more expensive than resistive devices, they’re also more versatile and flexible for a wider variety of applications.
They’re not sensitive to conductive objects such as water or dust, making them more suitable for environments that can’t afford the added maintenance and replacement costs of capacitive technology. Moreover, they can be operated with gloves and a variety of other input devices such as styluses or pencil erasers.
A disadvantage of resistive touch screens is that they’re more susceptible to dents and scratches, which can make them difficult or even impossible to repair. They don’t offer the same level of visibility as a capacitive display, either.
Resistive touch screens are ideal for panel control, graphical user interfaces, and other low-power applications where the user may not have access to a power source. They’re also great for applications that require gloved or non-conductive inputs, such as agricultural equipment, boats and underwater machinery.
Surface Acoustic Wave
A surface acoustic wave touch screen uses a glass substrate and special transducers to create an invisible grid of ultrasonic waves across the surface that are then collected by receivers. When the user touches the screen, some of the acoustic waves are absorbed and this causes a change in the amplitude. The controller of the SAW touchscreen detects this change in amplitude and then registers the touch.
SAW touch screens are very durable and will continue to work even if scratched because the glass panel is strong against scratches. This means that it is ideal for schools or public areas where there will be a high chance of people using the touchscreen.
Unlike other types of touch screen technology, SAW screens are not affected by chemicals and the glass does not contain any coatings or plastic films that can wear out over time. They are also IP rated, meaning that they can withstand a lot of exposure to water and dust.
Another great advantage of a SAW touch screen is that it has no wires or moving parts to wear out. This makes it a very cost effective option.
This type of touchscreen is very popular because it allows for a variety of different options such as customizable borders and logos. It is also a very flexible technology that can scale to any size of screen.
A SAW touch screen has two transmitting transducers (one on each axis) and four 45deg reflector patterns that send Rayleigh waves across the glass. Touch screen One of the patterns is on the horizontal and vertical edges and the other pattern is in the opposite corners.
These reflectors help to ensure that the acoustic waves travel evenly over the entire screen and that they travel up the opposite reflector. This way, when the user touches the screen, it will send a signal to the receiving transducers and the controller will know where the touch occurred.
The use of SAW technology for touchscreens has been increasing over the years because it is easy to make, is very durable and works well in many different environments. This is why it is a popular choice for many of the best touchscreen manufacturers around the world, including Elo.
Infrared
Infrared touch screens are one of the most reliable and durable types of touchscreen technology available. They feature no physical or electrical contacts and are stress-free, making them ideal for a wide range of applications that need high reliability.
They are used for a variety of different industries, including banking and financial services, transportation, healthcare, manufacturing, education, and many more. Infrared touch screen technology is typically found in ATMs, kiosks, POS systems, and interactive whiteboards.
This type of touch technology is a great alternative to traditional capacitive and resistive touchscreen technologies. It’s also quite durable and works with a wide range of inputs, including gloves, bare fingers, and styluses.
To achieve this, infrared touch screens use a grid of IR LEDs and photodetectors across the device’s surface. When any kind of touch occurs, it disrupts the light beams, causing these photodetectors to notice this disruption and relay it to controller electronics, which can then determine where the touch took place.
The resulting X and Y axis data is then transmitted to the PC or host for processing. This type of technology is also known as Linear Correlating Infrared (LCIR) technology.
It is the only IR touch technology with 100% sunlight immunity, ensuring a high quality and reliable touchscreen experience. It is also compatible with all types of input devices, from bare fingers to 5mm stylus and more.
Another great feature of this technology is that it’s also resistant to scratches and dust, ensuring a long life for the display. It’s also a great option for displays that are large in size, since it can handle the pressure of a large number of touches.
Compared to the other touch technologies, this technology is also very sensitive, which means it can detect and recognize multiple points of contact. It’s also extremely fast and responsive, enabling it to respond quickly to your commands.
The best thing about this type of touch screen is that it’s highly customizable, allowing you to choose which point of contact works for your needs. This is ideal for applications that require a lot of custom inputs or those that want to be able to support a variety of different finger sizes and textures.