Sensors | Free Full-Text | Review of Capacitive Touchscreen Technologies: Overview, Research Trends, and Machine Learning Approaches

analog digital capacitive surface touch screen    mutual surface acoustic wave (saw) acoustic wave acoustic pulse recognition dispersive signal technology traditional ir planar scatter detection optical frustrated total internal reflection

 https://www.researchgate.net/figure/Categories-of-touchscreen-technologies-This-figure-excludes-the-touchscreen-techniques_fig1_353304384

https://www.mdpi.com/1424-8220/21/14/4776 

https://en.wikipedia.org/wiki/Multi-touch