Programmable Phase Diffraction Grating for Synthetic Spectra Generation in Near IR Spectral Band

A new photonic chip, based on LNOI (Lithium Niobate on Insulator) substrates, has been developed and tested, applying MEOS (Micro Electro Optical System) micromachining techniques. The device allows to dynamically generate synthetic spectra of in principle any chemical species detectable in the base material transparency range (350 nm - 5500 nm wavelength). The synthetic spectrum is generated by producing a well-defined holographic phase map in the active layer of the LNOI substrate, by applying through an array of driving electrodes a calculated voltage distribution, thus rendering the photonic chip fully programmable even in real time. In this view the programmable photonic chip can be used as a dynamically reconfigurable spectral filter, suitable for applications in Spectroscopy, Remote Sensing, Optical Spectral Synthesis, etc. In this work a description of the developed technology is reported together with some preliminary results obtained in different experimental conditions.