Super resolving systems: Toraldo Pupils

(PUTO Project)

              The Collimator Prototype





Scheme of the prototype *


Position on 32 m Medicina Radiotelescope


Polyethylene lens detail **




Schematics of the collimator optics.

The beam-waist at the modified Cassegrain focus

is transformed by the two lenses and finally refocused 

on the feedhorn of the receiver.








       Lens fabrication by CNC milling

       machine technique



The realization of the prototype ***


First measurements

into the anechoic chamber ****



Normalized measured amplitude at the output beam-waist of the collimator for the open pupil (red dashed curve) and for the composed pupil (black solid curve), which is constituted by 4 circular coronae plus the central pupil. The external diameter is the same for both the open pupil and for the composed one.Both amplitudes were measured at their peak positions.

The prototype and the results of the first measurements will be presented at the  2nd URSI Atlantic Radio Science Conference” (Gran Canaria, Spain, 28 May- 1 June, 2018).

*   For the design and the realization of the prototype special thanks are due to Luca Cresci and Luca Carbonaro (INAF- Arcetri)

** The polyethylene lens were made Pasqualino Marongiu (INAF - OAC, Cagliari)

*** The support plates and the support for the Toraldo pupil were made by Andrea Donati (IFAC - CNR, Firenze)

**** The measures were carried out thanks to the contribution of Dario Panella (INAF- Arcetri)