[1] [1] X Hao, C Kuang, T Wang, et al.. Effects of polarization on the de-excitation dark focal spot in STED microscopy[J]. Journal of Optics, 2010, 12(11): 115707.

[2] [2] Z Gu, C Kuang, X Hao, et al.. Methods for generating a dark spot using phase and polarization modulation light[J]. Optik - International Journal for Light and Electron Optics, 2013, 124(7): 650-654.

[3] [3] S N Khonina, I Golub. Enlightening darkness to diffraction limit and beyond: Comparison and optimization of different polarizations for dark spot generation[J]. ournal of the Optical Society of America a-Optics Image Science and Vision, 2012, 29(7): 1470-1474.

[4] [4] T Erdogan, O King, G W Wicks, et al.. Circularly symmetrical operation of a concentric-circle-grating, surface-emitting, AlGaAs/GaAs quantum-well semiconductor-laser[J]. Appl Phys Lett, 1992, 60(16): 1921-1923.

[5] [5] R H Jordan, D G Hall. Free- space azimuthal paraxial wave- equation- the azimuthal bessel- gauss beam solution[J]. Opt Lett, 1994, 19(7): 427-429.

[6] [6] D G Hall. Vector-beam solutions of Maxwell′s wave equation[J]. Opt Lett, 1996, 21(1): 9-11。

[7] [7] P L Greene, D G Hall. Properties and diffraction of vector Bessel- Gauss beams[J]. Journal of the Optical Society of America a-Optics Image Science and Vision, 1998, 15(12): 3020-3027.

[8] [8] P L Greene, D G Hall. Focal shift in vector beams[J]. Opt Express, 1999, 4(10): 411-419.

[9] [9] K S Youngworth, T G Brown. Focusing of high numerical aperture cylindrical- vector beams[J]. Opt Express, 2000, 7(2): 77-87.

[10] [10] N Bokor, N Davidson. A three dimensional dark focal spot uniformly surrounded by light[J]. Opt Commun, 2007, 279(2): 229-234.

[11] [11] S N Khonina, I Golub．How low can STED go Comparison of different write-erase beam combinations for stimulated emission depletion microscopy[J]． Journal of the Optical Society of America a- Optics Image Science and Vision, 2012, 29(10): 2242-2246.

[12] [12] Y Dong, F Wang, C Zhao, et al.. Effect of spatial coherence on propagation, tight focusing, and radiation forces of an azimuthally polarized beam[J]. Physical Review A, 2012, 86(1): 013840.

[13] [13] B Richards, E Wolf． Electromagnetic diffraction in optical systems II. Structure of the image field in an aplanatic system[J]. Proceedings of the Royal Society of London Series a- Mathematical and Physical Sciences, 1959, 253(1274): 358-379.

[14] [14] E Wolf. Electromagnetic diffraction in optical systems I. An integral representation of the image field[J]． Proceedings of the Royal Society of London Series a-Mathematical and Physical Sciences, 1959, 253(1274): 349-357.

[15] [15] Y Xue, C Kuang, S Li, et al.. Sharper fluorescent super- resolution spot generated by azimuthally polarized beam in STED microscopy[J]. Opt Express, 2012, 20(16): 17653-17666.

[16] [16] N Bokor, Y Iketaki, T Watanabe, et al.. On polarization effects in fluorescence depletion microscopy[J]. Opt Commun, 2007, 272(1): 263-268.

[17] [17] Xiao Yun, Zhang Yunhai, Wang Zhen, et al.. Effect of incident laser on resolution of LSCM[J]. Optics and Precision Engineering, 2014, 22(1): 31-38.

[18] [18] M M Corral. Point spread function engineering in confocal scanning microscopy[C]. SPIE, 2003, 5182: 112-122.