How big can a touch screen be? Is there a limit to the size?

A large touchscreen display generally refers to one whose size is over 32 inches. On the market, the average size of large interactive touchscreen displays ranges from 42 to 85 inches. Large touch screens are mostly used for meetings, exhibitions, education, advertisements, mapping, etc. And big touchscreen displays can be mostly seen mounted on a wall or special stand.

The size limit of the touch screen is generally related to production technology. There are mainly four types of touch screens based on four typical technologies: infrared touch screens, resistive touch screens, surface acoustic wave touch screens, and projected capacitive touch screens. Each of them varies in its maximum size.

Infrared touch screens can be made very large. The maximum size can be made over 150 inches, but they cannot be made too small, because the cost of small-sized touch screens is similar to that of capacitive touch screens, and the user experience is not as good as projected capacitive touch screens. At present, they can basically meet the large-size requirements of touch screens on the market. However, infrared touch panels are easily interfered with surrounding lights and perform rather poorly in direct sunlight because infrared light beams generated by the user’s fingers can be disrupted by sun rays. It is suggested to place the infrared touch panel device in a dark location. So the infrared touch screen is not ideal for an extra large touch screen that demands high light interference capability.

Projected capacitive touch panels (PCAP touch screens) are known for their high precision and high-speed response times. Limited by the currently widely adopted technology (Indium Tin Oxide, ITO) on PCAP touch screens, the projected capacitive touch screen generally cannot exceed 65 inches, which cannot meet customers' requirements for a super-large size touch screen. PCAP has become popular after the material ITO (a cheaper and transparent conductive material) replaced the original, more expensive Antimony Tin Oxide (ATO). However, ITO material features relatively high resistivity, which makes it an obstacle to constructing a larger-format sensor. It is because of that as touch sensors’ sizes increase, their electrode length increases as well. As a result, it causes higher resistance, leading to a higher time constant, which causes a slower response. Within an appropriate size, the PCAP touch screen performs well in multi-touch functionality and relatively sensitive response at a relatively light and thin structure.

Resistive touch panels detect commands by pressure placed on the screen. They are generally limited to single-point touch. The resistive touch screens generally do not exceed 22 inches. For the surface acoustic wave touch screens, large size touchscreen and high durability are achievable but their sizes generally do not exceed 42 inches now. 

In addition to technical constraints, the usage scenarios and application scenarios should also be considered when designing the touch display’s size. Is it used for art exhibitions, classrooms, out-of-door advertising, and industrial monitoring? The size of interactive touch displays greatly depends on where they will be installed and who will make use of them. To be more specific, the installation location, height, and how many people will be using them at once and what kind of people will use them (kids, adults, senior people or handicapped people).

Top One Tech focuses on designing, developing and producing infrared touch screens and projected capacitive touch screens, and the sizes we mainly provide are as follows:

The projected capacitive touch screen ranges from 7 to 55 inches, featuring relatively high cost, anti-scratch, long service life, and suitable for multiple environments. The infrared touch screen ranges from 10.4 to 80+ inches, featuring low-price, easy-to-install, but low resolution.