The aim of the project was the development of a tactile display for the visually impaired as an all-in-one and portable device alternative to the Braille system, audio aids, screen reader, and text-to-speech devices. To date, display technology for sighted users has seen astonishing improvements and evolved to high-resolution screens even on mobile devices. However, the market still lacks such portable devices with text and graphical options translated from Braille. This is due to challenges in creating a tactile display, which effectively is an actuator array with thousands of individually addressable actuators. In contrast, for sighted people, creating large-scale displays, which effectively are arrays of millions of individually addressable light emitters (LEDs), has been evolved owing to advanced control electronics.
The impact of this research project on society stems from the potential to generate a device that supports the interaction of the visually impaired with all aspects of today’s modern information technologies. According to the World Health Organization (WHO) over 285 million people are reported as visually impaired globally, 2.55 million of whom in Europe. A Braille line costs around 10.000 € which corresponds to a prize of 125 € per character and 20 € per actuator. Charts, diagrams or maps can be neither processed by a screen reader nor by a Braille line. Windows, menus, icons or pictograms that are routinely used by sighted people in operating a computer, therefore, remain inaccessible to visually impaired users, which results in many problems at study centers or at work. Where graphical and online content (images, pictograms, and webpages) become increasingly important, the inability to perceive information visually is the primary inhibitor for inclusion.
The main objective of this research was a revolution in microactuator array technology with a fundamentally new concept termed the Capillary Lock Actuator (CaLA). CaLA is a novel bistable massively parallelizable microfluidic microactuator, which overcomes many of the limitations currently associated with microactuators. It can be operated with low-voltage control signals and requires low power for actuation. The project used CaLA actuator arrays for setting up individually addressable taxels. It was based on manufacturing techniques for highly complex microstructures in glass invented at the research group of the grant consolidator, the NeptunLab of Freiburg University.
