Sensors that are printed on flexible substrates represent a growing market. Although the biggest segment — blood glucose test strips — is currently shrinking, the next generation of printed sensors will enable other applications, from human-machine interfaces to environmental sensing. IDTechEx predicts the market for fully printed sensors will reach $7.6 billion by 2027.These sensors benefit from the latest materials and technologies in the printed electronics industry. While some may consist of a very simple structure with only a few electrodes, others are much more complex and require the deposition of multiple layers. What they have in common is the capability to be manufactured on plastic substrates, which offer advantages in terms of mechanical flexibility, thinness and weight reduction.