Advertising and information displays
We are increasingly using screens of all kinds in public spaces – we glance at them while moving on public transportation, shopping or ordering at a restaurant. The most commonly used technology for data visualization in this type of applications are LCD-TFT displays – they perform well in indoor and outdoor applications, and the appropriate selection of parameters ensures excellent readability of the content presented on them even in adverse conditions. In addition, they are ideal for implementation in devices that require touch functionality, in combination with touch sensors and protective glass.
Applications that fit into the framework of digital signage systems include:
- solutions used in transportation – screens in passenger information systems, including, for example, interactive timetables, boards announcing arrivals/departures and arrivals/departures, signage leading to the right stops/stations/gates, also, for example, self-check-in points;
- solutions used in commerce – various types of information and advertising media, including, for example, videowalls, kiosks and totems, as well as multimedia tables, signage such as signs;
- solutions becoming widespread in food service – menuboards – screens for presenting menus, ordering points, screens for tracking order completion.
Moreover, the use of electronic information and advertising media allows automating the process of changing the content presented on them. They can be updated in real time with just a few clicks in the appropriate program, without the need for a team of employees to, for example, replace their paper counterparts.
Displays adapted to public spaces
LCD-TFT displays are still the most commonly used data visualization technology in digital signage systems. In order to ensure optimal readability of the content, it is necessary to properly “tune” their optical parameters – in addition to ensuring the highest possible resolution, attention should also be paid to, for example, brightness or contrast, which we determine each time in relation to the conditions of the surrounding space. In addition, it is advisable to use models with full observation angles – they will allow to read the presented information or advertising from almost any plane.
When implementing LCD-TFT displays in outdoor applications, it is necessary to use solutions with the widest possible operating temperature ranges to ensure proper operation in changing weather conditions. These can be models for which this parameter is specified in the range from -20 to 70°C, although then it may be advisable to use additional elements, such as heaters or fans, allowing to maintain the temperature appropriate for the operation of electronic devices (not just modules with screens!). If the LCD-TFT displays are located in sunny areas, achieving optimal readability of the content, will be conditioned by the selection of adequate brightness – at least at the level of 1500 cd/m2. Moreover, in such situations, it is advisable to use models with hiTNI technology implemented, which provides protection of liquid crystals from sunlight damage. In addition, under the conditions of implementing any electronics in the outdoors, it is necessary to protect them from potential contaminants – such as dust and dirt, as well as water. This type of protection is achieved by placing it in an enclosure with the appropriate level of waterproofing, which is determined using IP codes defined by the PN-EN 60529 standard.
On some of the LCD-TFT displays used in digital signage systems, information or advertisements are presented around the clock – so continuous 24/7 operation is required of them. In such cases, it is worth paying attention to one more parameter, i.e. the LED lifetime – there are solutions on the market for which it is specified even at the level of 100,000 hours, which should be a guarantee – provided that the right conditions are ensured – of trouble-free operation for at least several years.
*Coatings can additionally be applied to the surface of the screens to improve “user-experience” – the user’s experience using the device. Among the most popular, for example, is anti-reflective (AR) coating, which reduces glare. In theory, it performs the same function as the anti-glare (AG) coating, but it is more effective – the use of different combinations of anti-reflective layers makes it possible to reduce the reflectance to 2%.
Touch solutions in digital signage systems
Some of the devices used in digital signage systems require touch functionality. There are several touch technologies available on the market, although in this type of application capacitive solutions, which, compared to other variants, are designed for intensive use, will be the best choice.
Each touch-sensor module is protected by protective glass. Using a several-millimeter variant (e.g., 5-millimeter), resistance to mechanical damage is achieved (without disturbing the function of touch). For such solutions, it is possible to determine the degree of resistance to mechanical loads (denoted by IK codes), which is defined by the EN 62262 standard. In addition, for fear of potential mechanical damage (e.g., done by an act of vandalism), an anti-shatter (AS) coating can be applied to the surface of the screen to prevent the spread of glass shards from a broken module.
Touch-enabled modules can be customized according to application requirements. Enhancements such as water rejection mode (which detects the presence of water on the screen surface) and palm rejection (which detects the presence of objects on the screen surface) may be necessary to ensure that the module functions properly even under adverse circumstances.
For devices that are operated by thousands of people, it is worth considering an additional anti-fingerprint (AF) coating, which reduces the possibility of dirt sticking to the screen surface, including grease (it is one of the components of a fingerprint). Also increasingly applied are anti-microbial (AM) coatings, which reduce the possibility of microbial proliferation (applied to screen surfaces by users – each of us leaves behind more or less dangerous traces); their effectiveness is determined to be at least 99.9%.
Stand out in the market
Designers of digital signage systems are outdoing themselves in the originality of the solutions used – ideally, they dictate trends, which allows them to stand out in the market. This is helped by the use of unusual formats, such as square or round LCD-TFT displays. Such models are available, among others. in Litemax’s offering.
The way to get unusual sizes and shapes is to cut LCD-TFT dies. It’s a technology that has made it possible to bring LCD-TFT displays into places where they have not previously been used due to space constraints, for example. These include. solutions used in vehicles placed, for example, over the aisles between compartments in trains, between the doors and the roof. Stretch models, or wide-format LCD-TFT displays with aspect ratios such as 16:2.2, 16:3, 16:4, 16:4.5 or 16:5, are used in them.
Vendors are outdoing themselves in creating new ways to achieve unusual LCD-TFT display formats. An example is the TARTAN technology developed by the AUO team , which uses native photomask manufacturing processes. The solutions realized in this way are distinguished by industrial quality – they can be used in both indoor and outdoor applications, including those that operate continuously – 24/7.
An alternative to LCD-TFT displays
LCD-TFT displays are still the most popular data visualization technology used in digital signage systems. However, an interesting “eco” alternative to them can be EPD displays, especially color variants like Palette from E Inka. It’s a simplified version of ACeP (Advanced Color ePaper; which allows images to be presented in full color gamut) technology solutions – Palette models are driven by simpler (and cheaper) electronics that allow for seven colors: black, white, red, yellow, blue, green and orange (i.e. popular colors used in advertising, for example). An example of such a solution is the AB1024-EGA.
Learn more about EPD displays.
