How to protect the screen from contamination?

Keeping the screen clean by wiping the surface with a microfiber cloth is actually the very last step in “cleanliness” and is up to the end user of the module. In designing a device, one should consider various means of securing the electronics inside to provide the best possible protection from contaminants, such as dust or water.

This article covers specific ways to protect information visualization devices from various contaminants. Adequate solutions during the design process will increase the chance of effectively protecting electronics from harmful factors that cause temporary or permanent damage.

Cleanroom – the cleanest spot

Some operations during the assembly of information visualization modules, such as combining displays with touch panels and protective or decorative glass, should be performed under conditions that prevent dust from penetrating various elements of the device. Appropriate conditions are found in cleanrooms. A cleanroom is a place where several contaminants are kept to a bare minimum. It is done to ensure the best (in this case: the cleanest) production environment possible. Cleanrooms are infrastructurally separated from the environment, equipped with air conditioning units with filters that prepare air injected into the cleanroom. Each user of the cleanroom has a direct impact on supporting appropriate conditions inside. They must follow specific rules to reduce the risk of contaminants entering the cleanroom.

Certain standards define the “cleanliness” level of a given cleanroom. One of them is the ISO 14644-1 standard. According to its specifications, Unisystem’s cleanroom meets the requirements of ISO class 6. We keep conditions suitable for operations such as bonding displays with touch panels and protective or decorative glass.

Learn more about the cleanroom.

Tightness defined in IP

During the design process of an electronic device intended for use in environments with the risk of dust or water contamination, it is recommended to secure the proper construction of the housing. It involves adequate tightness of the enclosure. Additionally, it is crucial to choose a suitable gasket. In terms of display protection, the gasket isolates the module, protecting the device far more than the case itself.

One way to determine the protection level of the enclosure is the IP (International Protection) codes, which are defined by the IEC 60529 standard. We all may encounter those codes in everyday life. For example, one can expect to find the IP44 code on switches designed for bathrooms. It indicates that the enclosure protects against the ingress of solid objects with a diameter of 1 mm and greater, and water splashes against the enclosure from any direction. The above mentioned standard also defines the level of protection against exposure to dangerous parts found inside the device’s enclosure, which the user might accidentally touch with his hand or finger. Other interesting examples are devices intended for use in production halls, which are expected to hold the IP65 level of enclosure protection against ingress of any dust, as well as water jets (12.5 l/min) poured on the enclosure from any direction. In some industries, such as food processing, equipment may require protection at the highest level described in EN 60529, which is the IP69 level – those enclosures are completely dust-tight and waterproof.

Learn more about IP codes.

No more fingerprints on the screen

Several nearly invisible coatings may be applied to the display’s surface to improve the device’s overall UX (user experience). One of the most popular solutions is anti-reflective (AR) coatings, which eliminate glare from natural and artificial light sources.

A solution recommended for touch screens is an anti-fingerprint (AF) coating. Its structure is extremely smooth, which significantly reduces the likelihood of dirt sticking to its surface, including grease, one of the elements of a visible fingerprint that one leaves on a glass surface.

Other solutions helpful with touch applications are anti-microbial (AM) coatings, which reduce the multiplication of microorganisms brought to the screen surface by users. Those solutions are meant for devices located in public spaces, such as food ordering kiosks, already present in almost every fast-food chain.

At every design phase, it is necessary to pay attention to the environment in which the device will be used. Adequate protection from contamination of electronic components will guarantee faultless operation, even when exposed to hazardous factors, such as caustic substances. In the end, the user’s only concern should be to buy microfiber cloth and keep the screen surface clear.