Are you designing a device with a screen? It is a step in the right direction. Modern electronic devices are increasingly equipped with displays for aesthetic reasons and, most importantly, functionality. Today, the screen is more than just an element that presents data. It has become a key user interface, enabling intuitive control, instant response to system messages, and direct interaction with device functions.
Table of Contents
In this guide, we present the most important issues to consider when choosing the optimal display for the solution you are designing. These issues almost always arise at the initial stage of cooperation – they help us better understand the needs of the end user and the specifics of the application in which our product is to be used.
Such a “technological interview” is not just a formality – it is the key to effective cooperation, which significantly speeds up the design process and avoids costly mistakes.
In this article, we discuss touch panel technologies and their calibration, multitouch functionality, the differences between air bonding and optical bonding, and ways to protect the screen, including protective glass and specialized coatings.
👉 Take a look at other articles in the series How to choose a display for your application?:
- part 1: technological basics and working environment,
- part 2: dimensions, formats, and device integration.
Touch panel
Many modern devices use touch panels as their primary user interface. They enable intuitive control of device functions without the need for physical buttons. Unisystem offers touch panels in various technologies, including capacitive (CTP), resistive (RTP), and infrared (IR). The choice depends on the application requirements and the conditions in which the device will be used.
A key aspect affecting the quality of a touch panel’s performance is its calibration. It determines whether the device will respond correctly to touch, even in situations that differ from ideal laboratory conditions. A properly calibrated panel can recognize gestures even when contaminants, including liquids, remain on the screen.
The same applies to operating devices while wearing gloves. It is difficult to imagine a situation in which production line workers would have to take off their gloves to operate the screen. This would not only be impractical but, in some cases, also potentially dangerous. Therefore, touch panels used in such applications must be precisely calibrated to ensure reliable operation in all conditions, including when wearing gloves.
At Unisystem, we help you choose the right touch panel technology and configure it to meet your functional requirements and perform well in real-world working conditions.
Multitouch
Multitouch technology enables simultaneous detection of multiple touch points on the screen surface. This solution has radically changed the way users interact with electronic devices. Thanks to multitouch, we can not only point but also zoom in/out and move or rotate objects on the screen, significantly increasing the intuitiveness and comfort of use.
Multitouch can come in different variants – from the simplest ones, supporting two points simultaneously (e.g., basic zoom in/out gestures), to advanced systems recognizing 10 or more touch points. The specifics of the application should dictate the choice of the optimal solution; for example, in interactive kiosks, it is worth considering full gesture support with multiple touchpoints.
Air bonding vs. optical bonding
One key stage in producing display modules is bonding components – from the matrix through the touch panel to the protective glass. In practice, two technologies are used: air bonding and optical bonding. They differ not only in the method of execution but also in the properties of the finished module.
The table below compares these two technologies:
| Parameter / Technology | Air bonding | Optical bonding |
| Construction | Components bonded mechanically – with a thin layer of air | Components bonded with optical adhesive (e.g., OCA resin) |
| Readability in light | Satisfactory | Enhanced |
| Mechanical strength | Standard | Increased |
| Shock resistance | Standard | Increased |
| Resistance to contamination (liquids/dust) | Limited | Increased |
| Resistance to extreme temperatures and temperature changes | Standard | Increased |
| Production cost | Lower | Higher |
| Application | Indoor/outdoor applications with standard environmental requirements | Indoor/outdoor applications with increased requirements – harsh environmental conditions |
You can learn more about bonding in our article.
Glass
In public spaces where devices are exposed to intensive use, a standard display module may require additional protection, such as a few millimeters of glass mounted on the front of the screen. This protects the display module against mechanical damage, including vandalism.
The resistance of glass to damage is classified using IK markings. This system is defined in the European standard EN 62262 (and its international equivalent – IEC 62262:2002). The scale comprises 10 levels – from IK01 to IK10, each corresponding to a specific impact energy value, expressed in joules. For example, glass with an IK08 rating can withstand an impact of 5 joules, corresponding to dropping a heavy object weighing 1.7 kg from a height of 300 mm. This level of protection significantly increases the structure’s durability and reduces the risk of damage by point impacts.
It is worth noting that the glass can be freely formed – it can be given non-standard shapes, holes can be cut out (e.g., for mechanical buttons), and it can also be painted with any graphic elements, including the manufacturer’s logo.
Coatings
Various types of coatings are available on the market that can be applied to protective glass or display surfaces. Their primary purpose is to improve the user experience when using the screen. Below, we describe selected types of coatings.
- AG (anti-glare) and AR (anti-reflective) – eliminate light reflections and improve image visibility.
- AF (antifingerprint) – an oleophobic coating that reduces fingerprints. It makes keeping the screen surface clean easier, even with frequent interaction.
- AM (antimicrobial) – limits the growth of microorganisms on the surface. It is recommended for public places with high traffic.
- AS (antishatter) – a layer that prevents glass shards from scattering in the event of breakage.
- UV – a UV-cured protective layer that eliminates the risk of component degradation caused by solar radiation.
Learn more about coatings in our article.
👉 Take a look at other articles in the series How to choose a display for your application?: