This paper proposes a simple method to achieve the optical transfer function of a circular pupil wavefront coding system with a separable phase mask in Cartesian coordinates. Based on the stationary phase method, the ...This paper proposes a simple method to achieve the optical transfer function of a circular pupil wavefront coding system with a separable phase mask in Cartesian coordinates. Based on the stationary phase method, the optical transfer function of the circular pupil system can be easily obtained from the optical transfer function of the rectangular pupil system by modifying the cut-off frequency and the on-axial modulation transfer function. Finally, a system with a cubic phase mask is used as an example to illustrate the way to achieve the optical transfer function of the circular pupil system from the rectangular pupil system.展开更多
A 2-cm long Bragg grating with reflectivity of~99.95% in B/Ge codoped optical fiber without hydrogen loading was created by phase-mask method with a pulsed KrF excimer laser at 248 nm. DC and AC components of refract...A 2-cm long Bragg grating with reflectivity of~99.95% in B/Ge codoped optical fiber without hydrogen loading was created by phase-mask method with a pulsed KrF excimer laser at 248 nm. DC and AC components of refractive index change were analyzed by monitoring transmission spectrum evolution during the writing process of fiber Bragg grating. The relations of the evolution of center wavelength and reflectivity with number of pulses were respectively investigated.展开更多
基金Project supported by the Natural Science Foundation of Zhejiang Province,China (Grant No. Y1110455)the Scientific Research Fund of Educational Department of Zhejiang Province,China (Grant No. Y200909691)the Science Foundation of Zhejiang Sci-Tech University (Grant No. 0913849-Y)
文摘This paper proposes a simple method to achieve the optical transfer function of a circular pupil wavefront coding system with a separable phase mask in Cartesian coordinates. Based on the stationary phase method, the optical transfer function of the circular pupil system can be easily obtained from the optical transfer function of the rectangular pupil system by modifying the cut-off frequency and the on-axial modulation transfer function. Finally, a system with a cubic phase mask is used as an example to illustrate the way to achieve the optical transfer function of the circular pupil system from the rectangular pupil system.
基金National Basic Research Program of China (2003CB314906)
文摘A 2-cm long Bragg grating with reflectivity of~99.95% in B/Ge codoped optical fiber without hydrogen loading was created by phase-mask method with a pulsed KrF excimer laser at 248 nm. DC and AC components of refractive index change were analyzed by monitoring transmission spectrum evolution during the writing process of fiber Bragg grating. The relations of the evolution of center wavelength and reflectivity with number of pulses were respectively investigated.