Touchscreen technology has emerged as the preferred user interface in a wide variety of computing, navigation, and communications devices. In fact, touchscreens are embedded in the majority of mobile display devices we use today and have revolutionized nearly all industries where a human-machine interface exists. While the development of the capacitive touch display is attributed to Eric Johnson in 1965, it was not until the early 1980s that touchscreens first became commercialized. Nearly two decades later, the release of Apple’s iPhones in 2007 marked a major step in the widespread global popularization of touchscreens.

Types of Touchscreens: Resistive, Capacitive, Infrared
Touch-enabled sensors, including resistive and capacitive, are constructed of conductive thin film coatings, dielectrics, and inks printed and patterned on glass or polymer films to form a grid of rows and columns. Touch activation occurs when the conductive layers make contact, and an electrical signal is generated at the X and Y interface. Resistive touch screens rely on physical touch to compress the conductive layers and activate the touch function, whereas Projective Capacitive touch screens (PCAPs) emit an electromagnetic field. As a finger or stylus approaches the touch screen surface, the change in capacitance is measured and electronically converted to enable activation at the proximity of the X and Y coordinates.
Projective Capacitive (PCAP) touch screens continue to supplant resistive touch screens in mobile electronics because of the intuitive user interface and attractive features, including:
- Multi-touch functionality, enabling dozens of touch activation points, swiping
- Robust glass front surface; 8H hardness, easier to clean, longer durability
- Better optical properties, including better transparency
- Adjustable touch sensitivity; flexible bezel-less designs
A resistive panel detects pressure on the top layer of the display and sends a signal to the circuit layer. Devices like these consist of two layers separated by a gap, activated by pressure when the layers are touched. Due to their pressure-sensitive nature, these devices can be operated with any input device, such as a gloved hand or a pen. Resistive devices can be more susceptible to damage and have poorer visibility in direct sunlight than a PCAP due to the reflective properties of the polyester films used to construct the resistive sensor.
In Infrared Touchscreens, the touch functionality is achieved by a series of LED emitters and detectors installed within the touchscreen bezel. Detectors embedded in the touchscreen overlay detect interruptions from infrared beams generated by the infrared LEDs. When an object touches the surface, it blocks the beams, sending a signal to the processor to respond with an action. The advantages of IR touch screens include image quality, multi-touch capability, and short response times. The performance of this technology can be affected by direct light, and its resolution may be lower than that of other types of touchscreens.

Applications In Military and Aerospace
Touchscreens provide rapid user interaction with displayed information (<20 milliseconds (ms) response time), enabling equipment operation, navigation, and processing of data. They can also be used in training simulators to improve combat readiness. Additional touchscreen applications within military and aerospace settings include command and control systems, military vehicles, aircraft and ships, maintenance of military equipment, and military medical equipment.
As PCAPs get designed into more demanding avionic and defense-related display applications, optical, electrical, and mechanical performance becomes more critical. While the functionality and durability of PCAP’s remain positive attributes for demanding applications, both radiated emissions and errant touch activation can occur. To tackle these issues, engineers are using a combination of specialized materials, software, and touchscreen controller adjustments to optimize PCAP performance.
Cevians Touchscreen Technologies
Cevians is a leader in touchscreens specifically engineered for defense and aerospace applications. In addition to Cevians’ broad range of standard and custom touchscreen products, touchscreen enhancements include: 1) Front surface glass touchscreens, chemically strengthened touch screen backer glass; 2) Optical EMI/RFI shielding materials including conductive mesh or low resistance, index-matched ITO coatings; 3) Optical enhancement of the PCAP/display system include front surface thin film antireflective coatings or circular polarizing layer; 4) Optical bonding of the touch screen to the front surface of the display to eliminate internal reflections and improve display contrast and high ambient light readability.
High-performance touchscreens from Cevians are designed for harsh, high-humidity environments, are sunlight readable, and have a long lifecycle. With a wide operating temperature range of -40 to +80, our touchscreens are MIL-STD-810-approved for military ground and airborne applications.
Learn More About Cevian’s Touchscreens
