摘要
We present intensity distributions of a supercontinuum laser passing through an apertured dispersion lens and find focal shift effects generated. The results show that, apart from the conventional negative focal shift, a positive focal shift also appears in the supercontinuum laser. The maximum intensity of the supercontinuum laser shifts toward the lens when the truncated parameter is small. However, it exceeds the focus of the central wavelength and a positive focal shift appears in the supercontinuum laser with large truncated parameter. Both of the maximum intensities shift away from the focus when the bandwidth of the supercontinuum laser increases, while the shift direction is opposite. No focal shift appears when the bandwidth and the truncated parameter satisfy some conditions.
We present intensity distributions of a supercontinuum laser passing through an apertured dispersion lens and find focal shift effects generated. The results show that, apart from the conventional negative focal shift, a positive focal shift also appears in the supercontinuum laser. The maximum intensity of the supercontinuum laser shifts toward the lens when the truncated parameter is small. However, it exceeds the focus of the central wavelength and a positive focal shift appears in the supercontinuum laser with large truncated parameter. Both of the maximum intensities shift away from the focus when the bandwidth of the supercontinuum laser increases, while the shift direction is opposite. No focal shift appears when the bandwidth and the truncated parameter satisfy some conditions.
基金
Supported by Science and Technology Planning Project of Hunan Province under Grant No 2013SK3144
Scientific Research Fund of Hunan Provincial Education Department under Grant No 11A011
the Construct Program of Key Discipline in Hunan Province
Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province in China
