Which touch screen technology is best?

Touchscreen technology

Sihovision are exported all over the world and different industries with quality first. Our belief is to provide our customers with more and better high value-added products. Let's create a better future together.

A resistive touchscreen is a type of touch-sensitive display that works by detecting pressure applied to the screen.[2] It is composed of two flexible sheets coated with a resistive material and separated by an air gap or microdots.[3]

Description and operation

There are two different types of metallic layers. The first type is called matrix, in which striped electrodes on substrates such as glass or plastic face each other. The second type is called analogue which consists of transparent electrodes without any patterning facing each other. As of analogue offered lowered production costs.[citation needed] When contact is made to the surface of the touchscreen, the two sheets are pressed together. On these two sheets there are horizontal and vertical lines that, when pushed together, register the precise location of the touch. Because the touchscreen senses input from contact with nearly any object (finger, stylus/pen, palm) resistive touchscreens are a type of "passive" technology.

For example, during the operation of a four-wire touchscreen, a uniform, unidirectional voltage gradient is applied to the first sheet. When the two sheets are pressed together, the second sheet measures the voltage as distance along with the first sheet, providing the X coordinate. When this contact coordinate has been acquired, the voltage gradient is applied to the second sheet to ascertain the Y coordinate. These operations occur within a few milliseconds,[4][5] registering the exact touch location as contact is made, provided the screen has been properly calibrated for variations in resistivity.[6]

Resistive touchscreens can have high resolution ( x or higher), providing accurate touch control. Because the touchscreen responds to pressure on its surface, contact can be made with a finger or any other pointing device.[citation needed]

Comparison with other touchscreen technology

Resistive touchscreen technology works well with almost any stylus-like object, and can also be operated with gloved fingers and bare fingers alike. In some circumstances, this is more desirable than a capacitive touchscreen, which needs a capacitive pointer, such as a bare finger (though some capacitive sensors can detect gloves and some gloves can work with all capacitive screens). A resistive touchscreen operated with a stylus will generally offer greater pointing precision than a capacitive touchscreen operated with a finger. Costs are relatively low when compared with active touchscreen technologies, but are also more prone to damage.[7] Resistive touchscreen technology can be made to support multi-touch input. Single-touch screens register multiple touch inputs in their balanced location and pressure levels.[8]

For people who must grip the active portion of the screen or must set their entire hand down on the screen, alternative touchscreen technologies are available, such as an active touchscreen in which only the stylus creates input and skin touches are rejected. However, newer touchscreen technologies allow the use of multi-touch without the aforementioned vectoring issues.[8]

Where conditions allow bare finger operation, the resistive screen's poorer responsiveness to light touches has caused it to generally be considered for use with low resolution screens and to lose market share to capacitive screens in the 21st century.[9] Projected capacitive touchscreen technology overtook resistive touchscreen technology in revenue in and in units in .[10]

See also

References

Tablet, smartphone, information desk, ticket machine or touch table &#; touch technology has made its way into all areas of life. There are a variety of touch technologies available that work in different ways, tracking touches using infrared light, pressure or even sound waves.

But which technology is the best? Of course, there are pros and cons to each type of touch screen, and each type can be suitable for a variety of application scenarios. In this article, we present the most widely used single- and multi-touch technologies and list the pros and cons of each.

Resistive touchscreens: Inexpensive, but no longer state of the art

Resistive touch displays use pressure for input. They consist of two panels covered with electrically conductive layers and separated by a small air gap. When someone applies pressure to the panel, whether by touching it with a finger, stylus or by placing something on the screen, the two layers touch. The resistance between the two layers is measured, which can then determine the location on the display where the contact takes place.

What are the advantages?

The advantages of resistive touch panels include very low production costs, flexibility in the type of touch (gloves, prosthetics or styluses can be used) and the durability of the screens to water and dust.

What are the disadvantages?

Resistive touchscreens cannot support multi-touch - only one touch point is recognised. This not only means that the screens are unsuitable for multiple users, but also that certain gestures are not recognised, such as pinching with two fingers to zoom. Due to the conductive layers, it is also often difficult to see the content on the display in bright light conditions such as direct sunlight. These screens often show more wear and tear during use, as users must apply pressure to the screen for a touch to be recognised.

Infrared touchscreens: Robust, but prone to error

In infrared touch displays, infrared light emitters and receivers are installed in a frame around the screen in front of the monitor glass. This creates a grid of infrared rays on the surface of the screen. When an object or finger touches the screen, the infrared light in this area is blocked and the position of the touch or object is then calculated using triangulation.

What are the advantages?

Infrared touch technology is robust because the display does not need to be touched or pushed for touch input, and any type of glass can be used for the monitor. IR touch displays do not rely on capacitance, so these optical devices work just as well with gloves or a plastic stylus as they do with a bare finger or metal object. The sensors are also very accurate, responsive, and comparatively inexpensive.

What are the disadvantages?

Touch input is dependent on the light situation and can be disturbed when exposed to sunlight or halogen light. Dust or dirt on the sensors can also lead to malfunctions. Furthermore, the number of simultaneous touch points is limited by the structure of the light barrier network. Infrared touchscreens support multitouch use, but not with the quality and accuracy that users are familiar with from their smartphones. Infrared screens can have blind spots, areas that do not register a touch, if the light sources and sensors do not properly cover the entire display. Multitouch object recognition is also not possible, as everything that breaks through the infrared rays is only evaluated as a touch point &#; rotation, for example, can&#;t be measured.

InGlassTM Touch: Premium infrared touch, but no object recognition

InGlassTM technology works in a similar way to classic infrared touch technology: sensors that transmit and receive infrared light are built in and form a kind of light curtain. However, they sit behind the glass pane of the display so that the light is guided directly through the glass. When the glass is touched, the light is disturbed and shows the sensors where the finger is.

What are the advantages?

The technology is characterised by high input precision, which makes it well suited for writing with passive pens or styluses. It also automatically distinguishes between pen, finger, and palm, which offers usability advantages when using touchscreen whiteboards. It also enables pressure strength detection with the finger, which means that an additional interaction level can be used, e.g. for zooming in and out. Multitouch use with 40 simultaneous touch points is also possible with InGlassTM displays. Ambient light is no longer a critical factor with this type of infrared touch recognition, so it works well in most light conditions.

What are the disadvantages?

Unfortunately, InGlassTM technology does not allow multitouch object recognition and is not optimally suited for multitouch tables. Capacitive and non-capacitive objects or dirt can equally cause a disturbance of the light network and thus lead to errors. Greasy fingers, for example, can leave a stain that is briefly recognised as a finger and triggers the corresponding touch effect.

PCAP (projected capacitive) touchscreens: The clear market leader

Unlike resistive touchscreens, capacitive touchscreens use the electrical properties of the human body as input. In today's PCAP touchscreens, there is a conductive layer in the form of a wafer-thin grid on the back of the glass panel. It projects a capacitive field through the pane. If an electrically conductive object or finger touches the glass pane, the capacitance at the intersection points of the conductive layer changes, allowing the position of the touch to be calculated. PCAP technology is now the most widely used touch technology, as it is used in virtually all tablets and smartphones, as well as in many large-format touchscreens.

What are the advantages?

If you are looking for a wear-resistant solution that combines high screen contrast and clarity with high and fast input accuracy, state-of-the-art capacitive touchscreens are the preferable option. Capacitive screens are exceedingly accurate, can handle multi-point input, and enable an unmatched range of functionality with object recognition and gesture recognition. Additionally, because the sensor is behind the glass, the displays are extremely robust. Changes in the ambient light situation have no effect on the sensors.

What are the disadvantages?

Due to the technical advantages, high-quality capacitive touchscreens can be a little more expensive than other options. They also generally react to capacitive, i.e., electrically conductive, materials. For example, liquid in the form of raindrops on a PCAP display results in touch input, which is why capacitive displays are not well suited for outdoor use. Gloves, which limit conductivity, can also make touch input difficult.

So, which touch technology is best?

We'll have to go with the classic lawyer's answer on that one: It depends. What is your budget? In what context will it be used? Should there be expansion possibilities? Multitouch, single touch, token recognition, pen recognition? Should the display only be used on the wall or also horizontally? Are there changing environmental conditions?

Capacitive touch technology has certainly evolved in recent years. Thanks to their widespread use, especially in mobile devices, they continue to make the greatest and most promising strides in terms of performance and cost. Through the use of artificial intelligence, capacitive displays are becoming more and more accurate and even enable completely new input possibilities that expand the usage potential of touch surfaces.

At Interactive Scape, we only use projected capacitive (PCAP) touchscreens because they are by far the best and most robust solution for horizontal use such as multi-touch tables with object recognition. Also because of the vivid images and the independence from the lighting conditions in the environment.

Still not sure which touch technology would be best for your project? We will be happy to advise you on your choice of touchscreen!

Contact us to discuss your requirements of camera rfid reader computer. Our experienced sales team can help you identify the options that best suit your needs.