Touchscreens are common in various modern devices such as smart phones, tablets, game consoles, etc. Currently the most common types of touchscreens are capacitive and resistive types. The capacitive touch technologies utilize the capacitance change induced by a finger when it is near an electrode. Multiple simultaneous touches, high sensitivity and zero bezel area are the key features of the capacitive technologies. However, they suffer from hardware complexity, high manufacturing cost, low yield and high power consumption. The resistive technologies have low cost, and low power consumption. But they have poor durability, poor optical quality, and need relatively high touch force and are lack of multi-touch.
Elastic waves are mechanical waves propagating inside solid structures. They can be generated and detected using transducers such as piezoelectric transducers. These waves are sensitive to mechanical perturbation such as the touch force generated by a finger or a stylus. By detecting the perturbed wave field and comparing it with the un-perturbed field, the location of the finger/stylus can be found. The potential advantages of this type of touchscreens include simplicity in hardware and low manufacturing cost. In this project, a prototype of elastic wave based touchscreens will be designed, manufactured and tested.
Depending on students' background, they will be involved in (1) the development of detection algorithms based on machine learning methods, or (2) experimental measurements of elastic waves.
Students who are interested in this project, please contact Supervisor for more information.
Students will learning (1) machine learning methods and their applications in inverse detection, (2) using piezoelectric transducers to send and receive waves.