English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

A novel type of a continuously zoomable telescope is based on two pairs ofadjacent toroidal lenses ("saddle lenses") in combination with standard opticalcomponents. Its variable magnification is adjusted by a mere rotation of thefour saddle lenses around the optical axis. This avoids the necessity ofclassical zoom systems to shift multiple lenses along the longitudinal axis ofthe setup. A rotationally tunable pair of saddle lens consists of twoindividual saddle lenses (also known as quadrupole lenses, or biconic lenses),which are arranged directly behind each other, acting as a "combi-saddle lens".The transmission function of such a combi-saddle lens corresponds to that of asingle saddle lens, but with an adjustable optical power which depends on themutual rotation angle between its two components. The optical system containstwo of these combi-saddle lenses, and acts as a cylindrical Kepler telescope inone plane, and as a cylindrical Galilei telescope in the orthogonal plane. Thetwo orthogonal Kepler/Galilei telescopes stay aligned and change theirmagnification factors in the same way when the telescope is zoomed by adjustingthe optical powers of the two combi-saddle lenses. Altogether this produces asharp image which is mirrored with respect to the axis of the Kepler telescope.Thus, in addition to the zooming capabilities of the telescope, it is alsopossible to rotate the resulting image by a rotation of the whole telescope, orof all included saddle lenses. We theoretically explain the operation principleof the telescope in both, a ray-optical and a wave-optical description.

Zoomable telescope by rotation of toroidal lenses