A transparent visuo-haptic input device with optical waveguide based thin film display, sensor and surface actuator

We demonstrate a transparent visuo-haptic input device. The device consists of optical waveguide based thin film display, sensor, and surface actuator. Highly transparent flexible display and sensor with high are fabricated by using Bisphenol A ethoxylate diacrylate (na = 1.5647 @ 632 nm) and Tetra diacrylate (na = 1.5031 @ 632 nm) for core and clad, respectively. The display and sensor are thin (thickness: < 70 μm), highly transparent (optical transmittance: as high as 90%) and designed as a form of 3 × 9 matrix. Surface actuator is fabricated as a combination of ITO electrode coated two rectangular glass plates, which are sandwiched with a constant air gap. The surface actuator produces electrically induced dynamic deformation responses of displacement as high as 157 μm and output force as large as 60 mN under a sinusoidal input voltage signal of 2 kV at 140 Hz. The visuo-haptic display integrating the three functional components is capable of realizing sufficient and human perceivable vibro-tactile response on a touch interface for QWERTY keypad.