We suggested and tried out several methods to hapticly visualize simple raster images in order to mediate a new experience. The third dimension was derived from the brightness value of discrete image function for individual pixels. We found out that aproximation should not disturb original object edges to facilitate the recognition of image content. It turned out that the method with adaptive triangular meshes gives the best results in haptic recognition of pictograms.
We also suggested some ways how to use these methods in teaching limited eye sight people (and not only them). The negative edge relief is very useful to hapticly visualize graphs of functions, adaptive meshes allow to recognize the letters of alphabet. The presented results are based on experiments with only 2 individual subjects (including author). In future we plan to test described methods on more subjects systematically.
This work was supported by a research grant, from Grant Agency of Czech Republic, Contract No. GACR 201/98/K041.