Advancements are reported in computer-generated holography proofing RGB 4K display through a new strategy based on diffraction model-driven deep networks. In the new 4K-DMDNet, the network is not a “black box” anymo...Advancements are reported in computer-generated holography proofing RGB 4K display through a new strategy based on diffraction model-driven deep networks. In the new 4K-DMDNet, the network is not a “black box” anymore. Rather, the input-output relation must obey to the physics of wavefront propagation, which is embedded here as a constraint. Thus, a labelled dataset is not required, and the model shows superior generalization capabilities with respect to data-driven approaches. The method is promising for the new generation of RGB 4K holographic display, as well as augmented and virtual reality systems.展开更多
The characterization of pyroelectric materials is essential for the design of pyroelectric-based devices.Pyroelectric current measurement is the commonly employed method,but can be complex and requires surface electro...The characterization of pyroelectric materials is essential for the design of pyroelectric-based devices.Pyroelectric current measurement is the commonly employed method,but can be complex and requires surface electrodes.Here,we present noncontact electrostatic voltmeter measurements as a simple but highly accurate alternative,by assessing thermally-induced pyroelectric surface potential variations.We introduce a refined model that relates the surface potential variations to both the pyroelectric coefficient and the characteristic figure of merit(FOM)and test the model with square-shaped samples made from PVDF,LiNbO3 and LiTaO3.The characteristic pyroelectric coefficient for PVDF,LiNbO3 and LiTaO3 was found to be 33.4,59.9 and 208.4μC m−2 K−1,respectively.These values are in perfect agreement with literature values,and they differ by less than 2.5%from values that we have obtained with standard pyroelectric current measurements for comparison.展开更多
文摘Advancements are reported in computer-generated holography proofing RGB 4K display through a new strategy based on diffraction model-driven deep networks. In the new 4K-DMDNet, the network is not a “black box” anymore. Rather, the input-output relation must obey to the physics of wavefront propagation, which is embedded here as a constraint. Thus, a labelled dataset is not required, and the model shows superior generalization capabilities with respect to data-driven approaches. The method is promising for the new generation of RGB 4K holographic display, as well as augmented and virtual reality systems.
基金supported by the European Horizon 2020 grant“SensApp”under Grant Agreement No.829104.
文摘The characterization of pyroelectric materials is essential for the design of pyroelectric-based devices.Pyroelectric current measurement is the commonly employed method,but can be complex and requires surface electrodes.Here,we present noncontact electrostatic voltmeter measurements as a simple but highly accurate alternative,by assessing thermally-induced pyroelectric surface potential variations.We introduce a refined model that relates the surface potential variations to both the pyroelectric coefficient and the characteristic figure of merit(FOM)and test the model with square-shaped samples made from PVDF,LiNbO3 and LiTaO3.The characteristic pyroelectric coefficient for PVDF,LiNbO3 and LiTaO3 was found to be 33.4,59.9 and 208.4μC m−2 K−1,respectively.These values are in perfect agreement with literature values,and they differ by less than 2.5%from values that we have obtained with standard pyroelectric current measurements for comparison.