5 Innovative Printing & Flexible Sensor Technologies In The 2020s

The following contribution is from another author.

At some point in time, you’ve heard someone say, “Out with the old and in with the new.” That’s exactly how it is with printed flexible sensors, which provide a plethora of benefits like flexibility, low weight, and lower manufacturing costs compared to their dated counterparts. Printed flexible sensors can also measure a wide variety of parameters and are one of the industry-leading applications in industrial IoT (Internet of Things), smart buildings, automotive interiors, and wearable devices. 

Here are the top five innovative printing and flexible technologies of the 2020s and their related applications:

Hybrid Piezoresistive & Capacitive Sensors 

Today, it’s become the norm for smartphones and tablets to feature touch screens thanks to piezoresistive and capacitive sensor technology. These hybrid piezoresistive and capacitive sensors rely on multilayer printed film to detect pressure and proximity changes on a device due to its membrane switch keypad. The sensors enable buttons that illuminate before contact and are activated when hard pressure is applied. In addition, they work well with robot grippers that detect when their “fingers” are close to objects and measure their pressure distribution. 

Thin-Film Organic Image Sensors 

Many image sensors are made out of small pieces of rigid silicon. Furthermore, numerous semiconductors, such as printable organic semiconductors, are used to detect light. These light-absorbing sensors are quite thin (only a few hundred nanometers), and they’re cost-effective. Thin-film organic image sensors have also become applicable to biometrics because, unlike silicon, the spectrum of an organic semiconductor can be adjusted. 

Moisture Sensing Via RFID 

Due to the hard work of the Swedish company InviSense, a printable thin-film sensor has been invented that’s capable of detecting moisture. This development was accomplished by using a printed RFID (Radio Frequency Identification) antenna coil coated with moisture-absorbing material. Once moisture is absorbed, the capacitance of the coil goes through changes in its resonant frequency. In addition, this change can be detected remotely by an RFID reader. What’s beneficial about this approach is that the thin film format of the sensor allows for the possibility of its being placed behind enclosed spaces, such as bathroom tiles, which means that testing can be performed in non-destructive manners.

Printed pH Sensors 

The age of digital printing has seen many advancements in the last few years, from 3D models to printed pH sensors. However, most methods of measuring pH are often inaccurate, subjective, or costly. The German firm Accensors has recently developed a technique for printing pH sensors using a simple and affordable sensor that can be created by printing only one nanoliter of proprietary material. Printed temperature sensors are often created to accompany pH sensors and ensure they receive accurate temperature readings. Moreover, many printed pH and temperature sensors have been experimented with and introduced within prototypes for wound monitoring patches. 

“Electric Noses” of Printed Gas Sensor Arrays

In relation to touch, sight, and hearing, scent is one of the only remaining senses that hasn’t been successfully digitized. The main challenge with a sense of smell is that odors are composed of an array of gas molecules from different concentration ratios. However, the “electric nose” approach can solve this challenge by utilizing numerous semiconductors, such as carbon nanotubes. Gas compositions can then be officially determined by using algorithms to compare the conductivity changes between different sensor regions within referential data.

Printing sensor technologies have become much more advanced and innovative in recent years thanks to the progression of technology and materials. We hope that the list above has helped you better understand the importance of excelling in the fields of printing and flexible sensors.