We present an ultra compact and high resolution free space optical spectrometer and demonstrate it by using FDTD simulations. The miniature interferometer-based spectrometer is a series of submicron phase objects on a...We present an ultra compact and high resolution free space optical spectrometer and demonstrate it by using FDTD simulations. The miniature interferometer-based spectrometer is a series of submicron phase objects on a polymethyl methacrylate(PMMA) film with a CCD as the detector. The spectrum is obtained by solving a system of simultaneous linear equations. The Tikhonov regularization method is used to achieve a resolution at the picometer level. Compared with conventional spectrometers, the proposed device is low-cost and easy to fabricate due to its simple structure. Furthermore, its compact feature renders the device ideal for miniaturization and integration as the systems in microfluidics architectures and lab-on-chip designs.展开更多
In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation betw...In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation between the interference phase and temperature is established according to the working principle and the phase algorithm of the interferometer.Secondly,the optical mechanical thermal analysis model and thermal deformation data acquisition model are designed.The deformation data of the interference module and the imaging optical system at different temperatures are given by temperature load simulation analysis,and the phase error caused by thermal deformation is obtained by fitting.Finally,based on the wind speed error caused by thermal deformation of each component,a reasonable temperature control scheme is proposed.The results show that the interference module occupies the main cause,the temperature must be controlled within(20±0.05)℃,and the temperature control should be carried out for the temperature sensitive parts,and the wind speed error caused by the part is 3.8 m/s.The thermal drift between the magnification of the imaging optical system and the thermal drift of the relative position between the imaging optical system and the detector should occupy the secondary cause,which should be controlled within(20±2)℃,and the wind speed error caused by the part is 3.05 m/s.In summary,the wind measurement error caused by interference module,imaging optical system,and the relative position between the imaging optical system and the detector can be controlled within 6.85 m/s.The analysis and temperature control schemes presented in this paper can provide theoretical basis for DASH interferometer engineering applications.展开更多
A new interferometer for extreme ultraviolet (EUV) radiation with a laser produced plasma (LPP) laboratory source is under construction. The LPP source is operated with a Sn solid rod target on which pulsed YAG laser ...A new interferometer for extreme ultraviolet (EUV) radiation with a laser produced plasma (LPP) laboratory source is under construction. The LPP source is operated with a Sn solid rod target on which pulsed YAG laser is focused to produce high temperature plasma emitting EUV radiation. The source is equipped with a newly designed debris stopper protecting a condenser multilayer mirror from the particle debris of the target. The condenser mirror focuses the light onto an EUV beam-splitter to form transmitted and reflected paths for producing interference fringes of a sharing type. The optical configuration is of a common path based on a triangular path type with a focusing at the beam-splitter, which is enabled to produce fringes by a low coherence radiation with a standard optical quality beam-splitter. The fringes are recorded by an imaging plate with pixels as small as 25μm. The dynamic range of linearity in detection of the EUV light was found to be more than 10 4 with sensitivity of 10 4 photons/pixel, enough for the purpose of interferogram recording, possibly with one laser shot.展开更多
基金supported by the Hong Kong Research Grants Council under CERG project 411907 and 412208Nation-al Basic Research Program of China(973)(No.2009CB930600)
文摘We present an ultra compact and high resolution free space optical spectrometer and demonstrate it by using FDTD simulations. The miniature interferometer-based spectrometer is a series of submicron phase objects on a polymethyl methacrylate(PMMA) film with a CCD as the detector. The spectrum is obtained by solving a system of simultaneous linear equations. The Tikhonov regularization method is used to achieve a resolution at the picometer level. Compared with conventional spectrometers, the proposed device is low-cost and easy to fabricate due to its simple structure. Furthermore, its compact feature renders the device ideal for miniaturization and integration as the systems in microfluidics architectures and lab-on-chip designs.
文摘In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation between the interference phase and temperature is established according to the working principle and the phase algorithm of the interferometer.Secondly,the optical mechanical thermal analysis model and thermal deformation data acquisition model are designed.The deformation data of the interference module and the imaging optical system at different temperatures are given by temperature load simulation analysis,and the phase error caused by thermal deformation is obtained by fitting.Finally,based on the wind speed error caused by thermal deformation of each component,a reasonable temperature control scheme is proposed.The results show that the interference module occupies the main cause,the temperature must be controlled within(20±0.05)℃,and the temperature control should be carried out for the temperature sensitive parts,and the wind speed error caused by the part is 3.8 m/s.The thermal drift between the magnification of the imaging optical system and the thermal drift of the relative position between the imaging optical system and the detector should occupy the secondary cause,which should be controlled within(20±2)℃,and the wind speed error caused by the part is 3.05 m/s.In summary,the wind measurement error caused by interference module,imaging optical system,and the relative position between the imaging optical system and the detector can be controlled within 6.85 m/s.The analysis and temperature control schemes presented in this paper can provide theoretical basis for DASH interferometer engineering applications.
文摘A new interferometer for extreme ultraviolet (EUV) radiation with a laser produced plasma (LPP) laboratory source is under construction. The LPP source is operated with a Sn solid rod target on which pulsed YAG laser is focused to produce high temperature plasma emitting EUV radiation. The source is equipped with a newly designed debris stopper protecting a condenser multilayer mirror from the particle debris of the target. The condenser mirror focuses the light onto an EUV beam-splitter to form transmitted and reflected paths for producing interference fringes of a sharing type. The optical configuration is of a common path based on a triangular path type with a focusing at the beam-splitter, which is enabled to produce fringes by a low coherence radiation with a standard optical quality beam-splitter. The fringes are recorded by an imaging plate with pixels as small as 25μm. The dynamic range of linearity in detection of the EUV light was found to be more than 10 4 with sensitivity of 10 4 photons/pixel, enough for the purpose of interferogram recording, possibly with one laser shot.
