Haptic expression of images using a surface acoustic wave tactile display mouse

A surface acoustic wave (SAW) tactile display has been developed and installed on a PC mouse button. To indicate roughness sensation, the display was controlled so that an alternative shear force according to operator's action could be provided to his/her finger skin. Using the mouse, they could enjoy roughness sensation as if they would rub on a rough solid surface. In this research, demonstration to express a gray-scale image through operator's mouse dragging action was carried out. While dragging over an image, the display provided different roughness according to the darkness under the mouse pointer. Displaying smoother sensation for lighter area of the image and rougher sensation for darker area, a tone of the image could be expressed through tactile sensation. We could feel as if a rough surface would be shaped into a figure. But we could not distinguish shape of the figures and difference of roughness, namely darkness of the image.