Reflecting type of zoom lens

摘要

A zoom lens comprises a plurality of optical elements each of which includes a transparent body having two refracting surfaces and a plurality of reflecting surfaces and is arranged so that a light beam enters the transparent body from one of the two refracting surfaces, repeatedly undergoes reflection, and exits from the other of the two refracting surfaces, and/or a plurality of optical elements on each of which a plurality of reflecting surfaces made from front surface mirrors are integrally formed, and each of which is arranged so that an entering light beam repeatedly undergoes reflection by the plurality of reflecting surfaces and exits from the optical element. In the zoom lens, the optical element which the light beam from an object enters first has an entrance pupil positioned on an object side of a first reflecting surface, and an image of the object is formed via the plurality of optical elements and zooming is performed by causing at least two optical elements from among the plurality of optical elements to vary their relative positions.