Bidirectional touch interaction for immaterial displays

Abstract

In this paper, we present an immaterial mid-air display with touchscreen capability and aerial tactile feedback. By augmenting a projected desktop fogscreen display with a 3D camera for touch detection and a focusable, modulated ultrasonic phased array for tactile feedback generation, very convincing yet completely immaterial user interfaces were constructed. A typical feedback response is delivered within 2 ms with a positional resolution of 2 mm and an active spot size of 10 mm at 100 mm distance. By combining a number of the tileable ultrasonic arrays, a tighter focus with much higher intensity can be produced.