The phase modulation characteristics of liquid crystal SLM (spatial light modulator) and the system for calibrating are proposed. Michelson interferometer is employed for measuring the modulation properties of devic...The phase modulation characteristics of liquid crystal SLM (spatial light modulator) and the system for calibrating are proposed. Michelson interferometer is employed for measuring the modulation properties of device. A system interface for operating SLM is designed with VC++ compiler. The initial distortion phase is determined by measuring the reflective interference, and modulation of device is compensated by using our system. By using the LUT (lookup table) data provided by manufacture the wavelength disperse calibration is also achieved successfully.展开更多
Fluorescence lifetime imaging can reveal the high-resolution structure of various biophysical and chemical parameters in a microenvironment quantitatively.However,the depth of imaging is generally limited to hundreds ...Fluorescence lifetime imaging can reveal the high-resolution structure of various biophysical and chemical parameters in a microenvironment quantitatively.However,the depth of imaging is generally limited to hundreds of micrometers due to aberration and light scattering in biological tissues.This paper introduces an iterative multi-photon adaptive compensation technique(IMPACT)into a two-photon fluorescence lifetime microscopy system to successfully overcome aberrations and multiple scattering problems in deep tissues.It shows that 400 correction modes can be achieved within 5 min,which was mainly limited by the frame rate of a spatial light modulator.This system was used for high-resolution imaging of mice brain tissue and live zebrafish,further verifying its superior performance in imaging quality and photon accumulation speed.展开更多
An optically addressed liquid crystal modulator for wavefront control of 1053 nm laser beam is reported in this paper.Its working principle, control method and spatial phase modulation capability are mainly introduced...An optically addressed liquid crystal modulator for wavefront control of 1053 nm laser beam is reported in this paper.Its working principle, control method and spatial phase modulation capability are mainly introduced. A new method of measuring the relationship between gray level and phase retardation is proposed. The rationality of the curve is further confirmed by designing special experiments. According to the curve, several spatial phase distributions have been realized by this home-made device. The results show that, not only the maximum phase retardation is larger than2π for 1053 nm wavelength, but also the control accuracy is high. Compared with the liquid crystal on silicon type spatial light modulator, this kind of modulator has the advantages of generating smooth phase distribution and avoiding the black-matrix effect.展开更多
A magnetic fluid based deformable mirror(MFDM) that could produce a large stroke more than 100 μm is designed and demonstrated experimentally with respect to the characteristics of the aberration of the liquid telesc...A magnetic fluid based deformable mirror(MFDM) that could produce a large stroke more than 100 μm is designed and demonstrated experimentally with respect to the characteristics of the aberration of the liquid telescope. Its aberration correction performance is verified by the co-simulation using COMSOL and MATLAB. Furthermore, the stroke performance of the MFDM and the decentralized linear quadratic Gaussian(LQG) mirror surface control approach are experimentally evaluated with a prototype of MFDM in an adaptive optics system to show its potential application for the large aberration correction of liquid telescopes.展开更多
文摘The phase modulation characteristics of liquid crystal SLM (spatial light modulator) and the system for calibrating are proposed. Michelson interferometer is employed for measuring the modulation properties of device. A system interface for operating SLM is designed with VC++ compiler. The initial distortion phase is determined by measuring the reflective interference, and modulation of device is compensated by using our system. By using the LUT (lookup table) data provided by manufacture the wavelength disperse calibration is also achieved successfully.
基金supported by the National Key Research and Development Program of China(No.2021YFF0502900)the National Natural Science Foundation of China(Nos.62175163,62225505,61935012,61835009,62127819,and 62205220)+2 种基金the Shenzhen Key Projects(No.JCYJ20200109105404067)the Shenzhen Talent Innovation Project(No.RCJC20210706091949022)the Shenzhen Science and Technology Planning Project(No.ZDSYS20210623092006020)。
文摘Fluorescence lifetime imaging can reveal the high-resolution structure of various biophysical and chemical parameters in a microenvironment quantitatively.However,the depth of imaging is generally limited to hundreds of micrometers due to aberration and light scattering in biological tissues.This paper introduces an iterative multi-photon adaptive compensation technique(IMPACT)into a two-photon fluorescence lifetime microscopy system to successfully overcome aberrations and multiple scattering problems in deep tissues.It shows that 400 correction modes can be achieved within 5 min,which was mainly limited by the frame rate of a spatial light modulator.This system was used for high-resolution imaging of mice brain tissue and live zebrafish,further verifying its superior performance in imaging quality and photon accumulation speed.
文摘An optically addressed liquid crystal modulator for wavefront control of 1053 nm laser beam is reported in this paper.Its working principle, control method and spatial phase modulation capability are mainly introduced. A new method of measuring the relationship between gray level and phase retardation is proposed. The rationality of the curve is further confirmed by designing special experiments. According to the curve, several spatial phase distributions have been realized by this home-made device. The results show that, not only the maximum phase retardation is larger than2π for 1053 nm wavelength, but also the control accuracy is high. Compared with the liquid crystal on silicon type spatial light modulator, this kind of modulator has the advantages of generating smooth phase distribution and avoiding the black-matrix effect.
基金supported by the National Natural Science Foundation of China(No.51675321)the Shanghai Municipal Natural Science Foundation(No.15ZR1415800)the Innovation Program of Shanghai Municipal Education Commission(No.14ZZ092)
文摘A magnetic fluid based deformable mirror(MFDM) that could produce a large stroke more than 100 μm is designed and demonstrated experimentally with respect to the characteristics of the aberration of the liquid telescope. Its aberration correction performance is verified by the co-simulation using COMSOL and MATLAB. Furthermore, the stroke performance of the MFDM and the decentralized linear quadratic Gaussian(LQG) mirror surface control approach are experimentally evaluated with a prototype of MFDM in an adaptive optics system to show its potential application for the large aberration correction of liquid telescopes.