Revista Brasileira de Ensino de Física
On-line version ISSN 1806-9126
SILVEIRA, Fernando Lang da and AXT, Rolando. A recurrent problem in geometrical optics: a not perceived image discontinuity at the magnifying glass. Rev. Bras. Ensino Fís. [online]. 2006, vol.28, n.4, pp. 421-425. ISSN 1806-9126. http://dx.doi.org/10.1590/S0102-47442006000400003.
Could we be looking at an object across a magnifying glass without perceiving the sudden image inversion - from virtual and erect to real and inverted - when the object moves away from the lens to a place a little farther than the focal distance? In this article we show that this effectively happens, as well with some eyeglasses lenses, like common reading glasses.
Keywords : magnifying glass; human eye; geometrical optics.