The state-of-the-art of image slicers: best performance and characteristics obtained in glass and metal

Image slicer technology has undergone great developments in the last decades. Innovative solutions are proposed for the largest night-time and solar telescopes, as well as for space applications. The science cases for the next generation of instruments require pushing image slicer technology beyond its current limits. Future developments are focused mainly in two key parameters: the reduction of the slicer mirror width and the improvement of the surface roughness. <br/> <br clear="all"/> The need for narrower slicer mirrors to achieve higher resolution, better surface roughness to reduce stray light, and innovative ideas for highly efficient Integral Field Spectrographs are investigated in two projects: MINOS and LUCES developed in the UK by a consortium between Durham University and University College London. The main results are presented in this manuscript.