Though we cannot imagine telescopes without mirrors or lenses, Laurent Koechlin and his team from the Observatoire Midi Pyrenees have done so and have envisaged a telescope that uses a metal sheet. This metal sheet consists of certain patterns which exploit the property of light bending around an object, called diffraction. By using Fresnel law of Diffraction, this metal plate has strategic patterns of holes which can be used to capture images onto a camera located some distance away from the Fresnel diffraction plate. This happens through a much smaller lens. By eliminating most of the weight and the problems associated with glass lenses which are major components of all telescopes, the images from space can be recorded easily as the Fresnel plate can be easily transported into space. Currently though, this model is undergoing testing and it might take some time for it to become commercially feasible. So all we can do, is to wait for the proof of concept before we can finally see it in space someday.
Via: NewScientist
