:-[ i'm sorry, i still can't understand what is virtual object....about mirage, can u explain the mirage that we can see during a hot day and in the desert? i've seen the applet, but i dunno whether that parabolic shape represent a mirror. If it is a mirror, y it is  call a mirage not reflection??? and i've also seen the optigone website. The things inside the parabolic shape thing, is it placed inverted,so tht the image is upright?