VPHG in the cold

The need of new generation dispersing elements with higher throughput and with higher dispersion capabilities has now met a widely shared answer in the technology of Volume Phase Holographic Gratings (VPHG). Our group is increasingly involved in the design and realization of VPHGs both for edge basic research, testing different manufacturers, sizes and resolutions, and for existing instruments upgrades, letting observing astronomers to take advantage of new possibilities with higher performances in their common use instrumentations. In Asiago Observatory, we refurbished the AFOSC camera and spectrograph. whose twins are spread all over the world, from Chilean based ESO-Danish telescope. to Bologna (Italy) South Africa and China. In our laboratory we reproduced the cooled environment of infrared cameras. obtaining the first proofs of the good behavior of VPHG in future IR spectrograph designs.