Metasurfaces composed of two-dimensional nanopillar arrays can manipulate light fields in desirable ways and exhibit the unique advantage of beam steering.Here,we experimentally demonstrate a metasurface-based wide-an...Metasurfaces composed of two-dimensional nanopillar arrays can manipulate light fields in desirable ways and exhibit the unique advantage of beam steering.Here,we experimentally demonstrate a metasurface-based wide-angle broadband all-dielectric blazed grating with an extreme incident angle of up to 80°,which is achieved by optimizing the wide-angle phase shifts and transmissivities of the unit cells.It exhibits a maximum diffraction efficiency of 72%and a high average efficiency of 64%over a wide range of incident angles from−80° to 45° at 1.55μm.Moreover,the proposed grating has a broad bandwidth of 200 nm(1.45-1.65μm),and average efficiencies of more than 50%can be achieved experimentally over the same incidence angles.Our results may pave the way for the creation of novel and efficient flat optical devices for wavefront control.展开更多
Far-field intensity and diffraction efficiency of the blazed reflection gratings illuminated with broad-bandwidth and divergent beam are investigated.When the spectral width and divergence of the incident beam with a ...Far-field intensity and diffraction efficiency of the blazed reflection gratings illuminated with broad-bandwidth and divergent beam are investigated.When the spectral width and divergence of the incident beam with a constant energy increase,the maximum intensity decreases,and the half width at e-2 of the maximum intensity becomes wider.Diffraction efficiency has no deterioration for the blazed grating with a proper groove shape even when the incident light contains a broad range of wavelengths and comes from a wide range of angles.展开更多
Grating optics lie in the heart of X-ray spectroscopy instruments.The low efficiency and angular dispersion of conventional single-layer-coated gratings significantly limit the transmission and energy resolution of mo...Grating optics lie in the heart of X-ray spectroscopy instruments.The low efficiency and angular dispersion of conventional single-layer-coated gratings significantly limit the transmission and energy resolution of monochromators and spectrometers,particularly in the tender X-ray region(E=1-5 keV).Multilayer-coated blazed gratings(MLBGs)operating at high diffraction orders offer the advantage of achieving both high efficiency and high dispersion simultaneously.Tender X-ray monochromators and spectrometers using different high-order MLBGs have been designed,all demonstrating one to two orders of magnitude higher transmission compared to conventional systems.By employing a 2400 l/mm MLBG at the-4th or-8th diffraction order,the theoretical energy resolution of the instrument is improved by two to three times at 2.5 keV.Two MLBGs operating at the-2nd and-4th orders have been fabricated,showcasing remarkable efficiencies of 34%-12%at 2.5 keV,surpassing that of single-layer-coated gratings by an order of magnitude.Further optimization of manufacturing accuracy can yield even higher efficiencies.The measured angular dispersion agrees well with theoretical predictions,supporting the potential for high resolution.High-order MLBG optics pave the way for a new generation of tender X-ray monochromators/spectrometers that offer both high transmission and high resolution.展开更多
In this paper, a binary blazed grating-based polarization independent filter on silicon on insulator （SOI） under full conical incidence is presented. The properties of the grating filter are investigated by rigorous...In this paper, a binary blazed grating-based polarization independent filter on silicon on insulator （SOI） under full conical incidence is presented. The properties of the grating filter are investigated by rigorous coupled-wave analysis. It＇s shown that the filter demonstrates high reflectivity （R 〉 99%） at its resonant wavelength, which stays the same under three different polarization states. It indicates that this grating filter is polarization-independent. The final data shows its polarization-dependent loss （PDL） is only 0.04 dB and the full width at half maximums （FWHMs） of the transverse electric （TE-） and transverse magnetic （TM-） polarized light are 0.24 and 0.46nm, respectively.展开更多
Single-point diamond turning (SPDT) is widely used in the machining of infrared materials and metal-based mirrors. Diamond tips can scratch material, replicate the shape of the tip, and create annular turning marks on...Single-point diamond turning (SPDT) is widely used in the machining of infrared materials and metal-based mirrors. Diamond tips can scratch material, replicate the shape of the tip, and create annular turning marks on optical surfaces, which can have unpredictable adverse effects on imaging. In order to predict the effect of turning marks diffraction on the degradation of imaging quality, a model of the influence of SPDT processing parameters on the reduction of system imaging MTF under the influence of ideal grating turning marks diffraction was established. The results show that the depth of the turning mark will lead to the decline of MTF, especially the low frequency information. Finally, a method is proposed to reduce the effect of turning marks diffraction through changing the processing parameters. .展开更多
基金support by the Advanced Integrated Optoelectronics Facility at Tianjin University
文摘Metasurfaces composed of two-dimensional nanopillar arrays can manipulate light fields in desirable ways and exhibit the unique advantage of beam steering.Here,we experimentally demonstrate a metasurface-based wide-angle broadband all-dielectric blazed grating with an extreme incident angle of up to 80°,which is achieved by optimizing the wide-angle phase shifts and transmissivities of the unit cells.It exhibits a maximum diffraction efficiency of 72%and a high average efficiency of 64%over a wide range of incident angles from−80° to 45° at 1.55μm.Moreover,the proposed grating has a broad bandwidth of 200 nm(1.45-1.65μm),and average efficiencies of more than 50%can be achieved experimentally over the same incidence angles.Our results may pave the way for the creation of novel and efficient flat optical devices for wavefront control.
基金Key Technologies R&D Programme of Hubei Province(2005AA101B10)
文摘Far-field intensity and diffraction efficiency of the blazed reflection gratings illuminated with broad-bandwidth and divergent beam are investigated.When the spectral width and divergence of the incident beam with a constant energy increase,the maximum intensity decreases,and the half width at e-2 of the maximum intensity becomes wider.Diffraction efficiency has no deterioration for the blazed grating with a proper groove shape even when the incident light contains a broad range of wavelengths and comes from a wide range of angles.
基金National Key Research and Development Program of China(2022YFA1603503)National Natural Science Foundation of China(12075170)。
文摘Grating optics lie in the heart of X-ray spectroscopy instruments.The low efficiency and angular dispersion of conventional single-layer-coated gratings significantly limit the transmission and energy resolution of monochromators and spectrometers,particularly in the tender X-ray region(E=1-5 keV).Multilayer-coated blazed gratings(MLBGs)operating at high diffraction orders offer the advantage of achieving both high efficiency and high dispersion simultaneously.Tender X-ray monochromators and spectrometers using different high-order MLBGs have been designed,all demonstrating one to two orders of magnitude higher transmission compared to conventional systems.By employing a 2400 l/mm MLBG at the-4th or-8th diffraction order,the theoretical energy resolution of the instrument is improved by two to three times at 2.5 keV.Two MLBGs operating at the-2nd and-4th orders have been fabricated,showcasing remarkable efficiencies of 34%-12%at 2.5 keV,surpassing that of single-layer-coated gratings by an order of magnitude.Further optimization of manufacturing accuracy can yield even higher efficiencies.The measured angular dispersion agrees well with theoretical predictions,supporting the potential for high resolution.High-order MLBG optics pave the way for a new generation of tender X-ray monochromators/spectrometers that offer both high transmission and high resolution.
基金Acknowledgements This work was partially supported by the National Natural Science Foundation of China （Grant No. 61177058）, and the National High Technology Research and Development Program of China （No. 2011AA010302）.
文摘In this paper, a binary blazed grating-based polarization independent filter on silicon on insulator （SOI） under full conical incidence is presented. The properties of the grating filter are investigated by rigorous coupled-wave analysis. It＇s shown that the filter demonstrates high reflectivity （R 〉 99%） at its resonant wavelength, which stays the same under three different polarization states. It indicates that this grating filter is polarization-independent. The final data shows its polarization-dependent loss （PDL） is only 0.04 dB and the full width at half maximums （FWHMs） of the transverse electric （TE-） and transverse magnetic （TM-） polarized light are 0.24 and 0.46nm, respectively.
文摘Single-point diamond turning (SPDT) is widely used in the machining of infrared materials and metal-based mirrors. Diamond tips can scratch material, replicate the shape of the tip, and create annular turning marks on optical surfaces, which can have unpredictable adverse effects on imaging. In order to predict the effect of turning marks diffraction on the degradation of imaging quality, a model of the influence of SPDT processing parameters on the reduction of system imaging MTF under the influence of ideal grating turning marks diffraction was established. The results show that the depth of the turning mark will lead to the decline of MTF, especially the low frequency information. Finally, a method is proposed to reduce the effect of turning marks diffraction through changing the processing parameters. .
