A Flash Light System for Individuals with Visual Impairment Based on TPVM

摘要

We propose a flashlight system to aid visually impaired people using the paradigm of temporal psychovisual modulation (TPVM), which is new display mode taking advantage of the limited flicker fusion frequency of human eyes and high refresh rate of modern display devices to achieve visual bifurcation effect. Structured light in visible spectrum is projected out onto the road surface and a synchronized camera detects the deformation and then the recognition system calculates the road flatness (e.g. smooth road, up-or down-stairs). To minimize the visual disturbance to other people, the TPVM display technique effectively conceals the structured light and making it basically a normal flashlight to normal observers. The system works in visible spectrum to minimize cost of the camera and the projector. We design fast and reliable recognition system with iterative dichotomiser 3(ID3) algorithm to differentiate condition of the pavement ahead into smooth road, wall ahead and up/down-stairs. Experimental results are presented to validate the proposed system.