The Internet of Things concept is growing in strength – according to some reports, the number of IoT-connected devices could be as high as 30 billion in 2020. and increase to as much as 75 billion in 2025. Much of it will be equipped with displays. We suggest which solution to choose to optimize costs while ensuring the highest quality of the final product.
Regardless of the type of IoT application, the best solution seems to be OLED displays , which do not require additional backlighting (each individual pixel is a light source). This translates not only into energy efficiency, but also low thickness (even less than 1 mm). The presented content is perfectly readable due to infinite contrast and unlimited viewing angles. In addition, OLED is distinguished from other solutions by its lightning-fast response time – less than 10 µs at 25°C, which allows for smooth animation playback of more than a hundred frames per second. The biggest disadvantage of OLEDs is the exorbitant price, which may prompt you to choose another type of display for the device you are designing.
Displays for wearable devices
A huge potential for IoT development lies in telemedicine. The need for continuous monitoring of a patient’s condition is creating a demand for wearable devices, such as pulse oximeters and blood pressure monitors, which alert the appropriate services when abnormalities in vital functions are detected. Smart bracelets are expected not only to be interesting, but above all practical in design. It is important to be able to read the presented content from different perspectives. The best solution here will be displays with full viewing angles that provide readable images in any position, without distortion. An alternative to OLEDs can be LCD displays – for monochrome solutions with an MVA matrix, and for color solutions with an IPS matrix. They are better value for money, but they are not ideal replacements (primarily due to, among other things, thickness, contrast or operating temperature range). In addition, during use, they require continuous backlighting generating increased power consumption. This can be a significant limitation for battery-powered wearable devices.
Energy-efficient e-papers
The best energy efficiency results are guaranteed by EPD displays (Electronic Paper Display, e-paper). They draw a small amount of power only when the image changes. It can be said that e-paper “imitates” traditional paper – the content presented is deceptively similar to printing technology, while duplicating some of its features, such as unlimited viewing angles. However, it should be taken into account that the legibility of the presented content under limited lighting conditions is only possible with access to an external light source. Unfortunately, while an attractive solution, it is the most expensive of the technologies described.
| model | diagonal | resolution | clarity | direction of observation | operating temperature |
|---|---|---|---|---|---|
| WEO006448ALPP3N00000 (OLED) | 0.66″ | 64×48 | 150 cd/m² | full | -40-80°C |
| WEO128128BSPP3N00000 (OLED) | 1.67″ | 128×128 | 80 cd/m² | full | -40-80°C |
| WF0096ATYAA3DNN0# (LCD-TFT) | 0.96″ | 80×160 | 500 cd/m² | full | -20-70°C |
| ET011TT2 (e-paper) | 1.1″ | 240×240 | not applicable | full | 0-50°C |
| ET013TT1 (e-paper) | 1.3″ | 256×256 | not applicable | full | 0-50°C |
Displays for smart buildings
The concept of “smart home” is becoming present in our lives – solutions for the central management of lighting or heating, as well as household appliances, are gaining popularity.
One way to control smart buildings is through wall-mounted panels. In this case, for cost optimization, the best solution will be to choose a LCD-TFT display with a TN matrix with a 12 o’clock viewing direction. This will make the content readable enough without using full observation angles. Nor will the need to illuminate the module be a problem – usually these types of panels are powered from the mains, so energy-saving requirements are not so restrictive. LCD displays can be easily combined with touch panels (both resistive and capacitive). It is also worth considering additional forms of protecting them, such as using an anti-fingerprint (AF) coating, which reduces the possibility of dirt sticking (including fingerprints remaining).
| model | diagonal | resolution | direction of observation | clarity | type of touch panel |
|---|---|---|---|---|---|
| WF43GTIAEDNT0# | 4.3″ | 480×272 | 12:00 | 350 cd/m² | resistive |
| WF50BTIFGDHGV# | 5.0″ | 800×480 | 12:00 | 350 cd/m² | resistive |
| WF70ATIAGDNC0# | 7.0″ | 800×480 | 12:00 | 350 cd/m² | capacitive |
Selected LCD-TFT displays for smart building control devices.
The described applications are only examples. We know from experience that each project requires an individual approach – asking the right questions, the answers to which are not always obvious.
Contact us to learn about our full range of displays for IoT applications.
