Development of a device transmitting 3-D scenery information by sound signals

Various types of visual substitutes have been developed to support visually impaired people. However, no practical device which can obtain and transmit scenery information to users has been developed to date. We propose a method of transmitting three-dimensional scenery information such as height, width and distance of objects in a scene. The distance to an object is indicated by the volume of sounds. The horizontal position is indicated by stereo sounds. The vertical position is indicated by delivering frequency-modulated sounds corresponding to the vertical position in a time-divided scanning method. A compact device applying this transmitting method is developed. The device is composed of stereo cameras, a compact range finder for obtaining spatial information in real time, a compact scenery information transmitter, and a headphone. The validity of the device is confirmed by several basic scene recognition and walking experiments.