A profilometer used for 3 dimension measurement of micro-surface topography is presented. The instrument is based on the vertical scanning microscopic interferometry （VSMI）. A Linnik type interference microscope is ...A profilometer used for 3 dimension measurement of micro-surface topography is presented. The instrument is based on the vertical scanning microscopic interferometry （VSMI）. A Linnik type interference microscope is used and the interferograms which present changes of surface profile are recorded with a CCD camera. A developed nano-positioning work stage with an integrated optical grating displacement measuring system realizes the precise vertical scanning motion during profile measurement. By a white-light phase shifting algorithm of arbitrary step, frames of interferograms are processed by a computer to rebuild and evaluate the measured profile. Because of the specialty of VSMI, the profilometer is suitable for both smooth and rough surface measurement. It can also be used to measure curved surfaces, dimension of micro electro mechanical systems （MEMS）, etc. The vertical resolution of the profilometer is 0.5 nm, and lateral resolution 0.5 μm.展开更多
Phase is one of the most important parameters of electromagnetic waves. It is the phase distribution that determines the propagation, reflection, refraction, focusing, divergence, and coupling features of light, and f...Phase is one of the most important parameters of electromagnetic waves. It is the phase distribution that determines the propagation, reflection, refraction, focusing, divergence, and coupling features of light, and further affects the intensity distribution. In recent years, the designs of surface plasmon polariton （SPP） devices have mostly been based on the phase modulation and manipulation. Here we demonstrate a phase sensitive multi-parameter heterodyne scanning near-field opti- cal microscope （SNOM） with an aperture probe in the visible range, with which the near field optical phase and amplitude distributions can be simultaneously obtained. A novel architecture combining a spatial optical path and a fiber optical path is employed for stability and flexibility. Two kinds of typical nano-photonic devices are tested with the system. With the phase-sensitive SNOM, the phase and amplitude distributions of any nano-optical field and localized field generated with any SPP nano-structures and irregular phase modulation surfaces can be investigated. The phase distribution and the interference pattern will help us to gain a better understanding of how light interacts with SPP structures and how SPP waves generate, localize, convert, and propagate on an SPP surface. This will be a significant guidance on SPP nano-structure design and optimization.展开更多
Utilizing reflection-based near-field scanning optical microscopy(NSOM) to image and analyze standing-wave patterns, we present a characterization technique potentially suitable for complex photonic integrated circuit...Utilizing reflection-based near-field scanning optical microscopy(NSOM) to image and analyze standing-wave patterns, we present a characterization technique potentially suitable for complex photonic integrated circuits. By raster scanning along the axis of a straight nano-waveguide in tapping mode and sweeping wavelength, detailed information of propagating waves in that waveguide has been extracted from analyses in both space and wavelength domains. Our technique needs no special steps for phase stabilization, thus allowing long-duration and environment-insensitive measurements. As a proof-of-concept test, in a silicon single-mode waveguide with a few of etched holes, the locations and reflection strengths of the inner defects have been quantified. The measurement uncertainty of the reflection amplitude is less than 25% at current stage. Our technique paves the way for non-destructively diagnosing photonic circuits on a chip with sub-wavelength spatial resolution and detailed information extraction.展开更多
[Objectives]To identify the authenticity of Longgu from the microscopic,infrared spectrum and chemical composition,and provide references for the quality control and evaluation methods of Longgu.[Methods]According to ...[Objectives]To identify the authenticity of Longgu from the microscopic,infrared spectrum and chemical composition,and provide references for the quality control and evaluation methods of Longgu.[Methods]According to the mineral characteristics of Longgu,the identification research was carried out by microscope observation,near-infrared spectroscopy and X-ray fluorescence spectrometer.By comparing the single polarizing and orthogonal polarizing characteristics of genuine and fake Longgu,a qualitative identification model of genuine Longgu was established based on the near-infrared spectrum of genuine Longgu,and the detection results of elements in Longgu were analyzed.[Results]The genuine Longgu had apatite optical properties,and was quite different from the fake Longgu of animal bones.Compared with modern animal bones,genuine Longgus had relatively less P and Ca,but they were enriched in elements Sr and F.The correlation coefficient model with good predictive ability can be established by using the near-infrared characteristic spectrum.[Conclusions]Polarizing microscope,near-infrared spectroscopy and X-ray fluorescence spectroscopy can improve the identification results of Longgu.展开更多
基金Project supported by the National Natural Science Foundation of China （Grant No.50175037）
文摘A profilometer used for 3 dimension measurement of micro-surface topography is presented. The instrument is based on the vertical scanning microscopic interferometry （VSMI）. A Linnik type interference microscope is used and the interferograms which present changes of surface profile are recorded with a CCD camera. A developed nano-positioning work stage with an integrated optical grating displacement measuring system realizes the precise vertical scanning motion during profile measurement. By a white-light phase shifting algorithm of arbitrary step, frames of interferograms are processed by a computer to rebuild and evaluate the measured profile. Because of the specialty of VSMI, the profilometer is suitable for both smooth and rough surface measurement. It can also be used to measure curved surfaces, dimension of micro electro mechanical systems （MEMS）, etc. The vertical resolution of the profilometer is 0.5 nm, and lateral resolution 0.5 μm.
基金supported by the National Natural Science Foundation of China(Grant Nos.61177089,61227014,and 60978047)
文摘Phase is one of the most important parameters of electromagnetic waves. It is the phase distribution that determines the propagation, reflection, refraction, focusing, divergence, and coupling features of light, and further affects the intensity distribution. In recent years, the designs of surface plasmon polariton （SPP） devices have mostly been based on the phase modulation and manipulation. Here we demonstrate a phase sensitive multi-parameter heterodyne scanning near-field opti- cal microscope （SNOM） with an aperture probe in the visible range, with which the near field optical phase and amplitude distributions can be simultaneously obtained. A novel architecture combining a spatial optical path and a fiber optical path is employed for stability and flexibility. Two kinds of typical nano-photonic devices are tested with the system. With the phase-sensitive SNOM, the phase and amplitude distributions of any nano-optical field and localized field generated with any SPP nano-structures and irregular phase modulation surfaces can be investigated. The phase distribution and the interference pattern will help us to gain a better understanding of how light interacts with SPP structures and how SPP waves generate, localize, convert, and propagate on an SPP surface. This will be a significant guidance on SPP nano-structure design and optimization.
基金Project supported by National Key R&D Program of China(Grant No.2017YFA0303800)National Natural Science Foundation of China(Grant No.61575218)Defense Industrial Technology Development Program,China(Grant No.JCKY201601C006)
文摘Utilizing reflection-based near-field scanning optical microscopy(NSOM) to image and analyze standing-wave patterns, we present a characterization technique potentially suitable for complex photonic integrated circuits. By raster scanning along the axis of a straight nano-waveguide in tapping mode and sweeping wavelength, detailed information of propagating waves in that waveguide has been extracted from analyses in both space and wavelength domains. Our technique needs no special steps for phase stabilization, thus allowing long-duration and environment-insensitive measurements. As a proof-of-concept test, in a silicon single-mode waveguide with a few of etched holes, the locations and reflection strengths of the inner defects have been quantified. The measurement uncertainty of the reflection amplitude is less than 25% at current stage. Our technique paves the way for non-destructively diagnosing photonic circuits on a chip with sub-wavelength spatial resolution and detailed information extraction.
基金Supported by the Subject Talent Research Promotion Program for"Xinglin Scholars"of Chengdu University of Traditional Chinese Medicine(ZRQN2020019).
文摘[Objectives]To identify the authenticity of Longgu from the microscopic,infrared spectrum and chemical composition,and provide references for the quality control and evaluation methods of Longgu.[Methods]According to the mineral characteristics of Longgu,the identification research was carried out by microscope observation,near-infrared spectroscopy and X-ray fluorescence spectrometer.By comparing the single polarizing and orthogonal polarizing characteristics of genuine and fake Longgu,a qualitative identification model of genuine Longgu was established based on the near-infrared spectrum of genuine Longgu,and the detection results of elements in Longgu were analyzed.[Results]The genuine Longgu had apatite optical properties,and was quite different from the fake Longgu of animal bones.Compared with modern animal bones,genuine Longgus had relatively less P and Ca,but they were enriched in elements Sr and F.The correlation coefficient model with good predictive ability can be established by using the near-infrared characteristic spectrum.[Conclusions]Polarizing microscope,near-infrared spectroscopy and X-ray fluorescence spectroscopy can improve the identification results of Longgu.
