How blind students understand light: a comparison between blind and nonblind students' ideas

Physics education for blind students is a research field that still lacks systematic and detailed investigation. What has been done so far is the study of isolated cases. Our interest in this subject comes from epistemological questions about teaching physics to blind students. Thus, we ask: How do blind students understand physics concepts and apply them? How do these students manage to construct their physics knowledge? As physics and other sciences are based on visual references, it is interesting to know if blind students' previous ideas about light, gathered through sound and tactile experiences, is different from those of nonblind students. In this work we interview blind students using the oral history methodology (life history and thematic), seeking information about their visual ability, school experience and previous concepts about their general understanding of light and geometrical optics. We analyse the collected data and compare them with nonblind students' ideas about the same subject.