Students’ perceptual practices with real and virtual images

Abstract

This study examined how university students learn real and virtual images using vision-based perception cues such as binocular parallax, monocular parallax, binocular fuzziness, monocular fuzziness, and convergence. Two activities on the cues were conducted with university students. In the pre-activity, they learned about the perceptual cues and practiced each cue without using a lens or mirror. Then, four setups with convex lenses and concave mirrors were designed, enabling the study of the clues, and in the main activity, the students practiced each cue on the setups. Their experiences in the main activity were acquired through written reports, student observations, and interviews. Following the activities, the students related their perceptual experiences to their prior knowledge of images. Additionally, the students were questioned regarding their opinions on the use of five perceptual cues as image-learning strategies. The students found that the observation of binocular parallax in a lens or mirror represents a real image. They identified the relative positions of real and virtual images and their objects with the help of monocular parallaxes. They also connected their understanding of optics to the perceptual cues that real images appeared in front of mirrors and on the opposite side of the object in lenses, but virtual images appeared behind mirrors and on the object side of lenses. Conclusions were suggested for optics instructions.