[1] Duntley S Q. Light in the sea[J]. Journal of the Optical Society of America, 53, 214-233(1963).

     Duntley S Q. Light in the sea[J]. Journal of the Optical Society of America, 53, 214-233(1963).

[2] Mullen L, Cochenour B, Laux A et al. Optical modulation techniques for underwater detection, ranging and imaging[J]. Proceedings of SPIE, 8030, 803008(2011). http://spie.org/x648.html?product_id=883493

     Mullen L, Cochenour B, Laux A et al. Optical modulation techniques for underwater detection, ranging and imaging[J]. Proceedings of SPIE, 8030, 803008(2011). http://spie.org/x648.html?product_id=883493

[3] Ma Y, Ji H, Liang K et al. Application of modulated lidar on optical carrier for ocean exploration[J]. Laser Technology, 32, 346-349(2008).

     Ma Y, Ji H, Liang K et al. Application of modulated lidar on optical carrier for ocean exploration[J]. Laser Technology, 32, 346-349(2008).

[4] Bartolini L, de Dominicis L, de Collibus M F et al. . Underwater three-dimensional imaging with an amplitude-modulated laser radar at a 405 nm wavelength[J]. Applied Optics, 44, 7130-7135(2005). http://www.opticsinfobase.org/abstract.cfm?URI=ao-44-33-7130

     Bartolini L, de Dominicis L, de Collibus M F et al. . Underwater three-dimensional imaging with an amplitude-modulated laser radar at a 405 nm wavelength[J]. Applied Optics, 44, 7130-7135(2005). http://www.opticsinfobase.org/abstract.cfm?URI=ao-44-33-7130

[5] Illig D W, Rumbaugh L, Jemison W D et al. Statistical backscatter suppression technique for a wideband hybrid lidar-radar ranging system. [C]∥2014 Oceans-St. John'S, September 14-19, 2014, St. John's, NL, Canada. New York: IEEE, 7003086(2014).

     Illig D W, Rumbaugh L, Jemison W D et al. Statistical backscatter suppression technique for a wideband hybrid lidar-radar ranging system. [C]∥2014 Oceans-St. John'S, September 14-19, 2014, St. John's, NL, Canada. New York: IEEE, 7003086(2014).

[6] Kumar S C, Samanta G K, Devi K et al. High-efficiency, multicrystal, single-pass, continuous-wave second harmonic generation[J]. Optics Express, 19, 11152-11169(2011). http://www.ncbi.nlm.nih.gov/pubmed/21716344

     Kumar S C, Samanta G K, Devi K et al. High-efficiency, multicrystal, single-pass, continuous-wave second harmonic generation[J]. Optics Express, 19, 11152-11169(2011). http://www.ncbi.nlm.nih.gov/pubmed/21716344

[7] Hao L Y, Su C, Qi Y F et al. Second harmonic gereration characteristics of continuous wave all-fiber laser oscillator in PPMgO∶LN[J]. Chinese Journal of Lasers, 40, 0602007(2013).

     Hao L Y, Su C, Qi Y F et al. Second harmonic gereration characteristics of continuous wave all-fiber laser oscillator in PPMgO∶LN[J]. Chinese Journal of Lasers, 40, 0602007(2013).

[8] Liu X, Shen X J, Yin J L et al. Research on extending temperature acceptance bandwidth of second harmonic generation in cascaded crystals[J]. Chinese Journal of Lasers, 45, 0108001(2018).

     Liu X, Shen X J, Yin J L et al. Research on extending temperature acceptance bandwidth of second harmonic generation in cascaded crystals[J]. Chinese Journal of Lasers, 45, 0108001(2018).

[9] Zhang Y P, Zhang H Y, He Z H et al. A 36 W intracavity-frequency-doubled diode-side-pumped Nd∶YAG/KTP continuous wave green laser[J]. Acta Physica Sinica, 58, 4647-4651(2009).

     Zhang Y P, Zhang H Y, He Z H et al. A 36 W intracavity-frequency-doubled diode-side-pumped Nd∶YAG/KTP continuous wave green laser[J]. Acta Physica Sinica, 58, 4647-4651(2009).

[10] Wu J R, Lü Z Q, Lu X et al. Characteristics of second harmonic generation in erbium doped femtosecond fiber lasers based on quasi phase matching[J]. Chinese Journal of Lasers, 45, 0701001(2018).

     Wu J R, Lü Z Q, Lu X et al. Characteristics of second harmonic generation in erbium doped femtosecond fiber lasers based on quasi phase matching[J]. Chinese Journal of Lasers, 45, 0701001(2018).

[11] Zhao R C, Fu X H, Sun J F et al. High power 507.4 nm continuous laser generated by high efficient external cavity frequency doubling[J]. Chinese Journal of Lasers, 44, 0701001(2017).

     Zhao R C, Fu X H, Sun J F et al. High power 507.4 nm continuous laser generated by high efficient external cavity frequency doubling[J]. Chinese Journal of Lasers, 44, 0701001(2017).

[12] Stappel M, Kolbe D, Walz J. Continuous-wave, double-pass second-harmonic generation with 60% efficiency in a single MgO∶PPSLT crystal[J]. Optics Letters, 39, 2951-2954(2014).

     Stappel M, Kolbe D, Walz J. Continuous-wave, double-pass second-harmonic generation with 60% efficiency in a single MgO∶PPSLT crystal[J]. Optics Letters, 39, 2951-2954(2014).

[13] Mizuuchi K, Morikawa A, Sugita T et al. High-power continuous wave green generation by single-pass frequency doubling of a Nd∶GdVO4 laser in a periodically poled MgO∶ LiNbO3 operating at room temperature[J]. Japanese Journal of Applied Physics, 42, L1296-L1298(2003).

     Mizuuchi K, Morikawa A, Sugita T et al. High-power continuous wave green generation by single-pass frequency doubling of a Nd∶GdVO4 laser in a periodically poled MgO∶ LiNbO3 operating at room temperature[J]. Japanese Journal of Applied Physics, 42, L1296-L1298(2003).

[14] Kumar S C, Samanta G K, Ebrahim-Zadeh M. High-power, single-frequency, continuous-wave second-harmonic-generation of ytterbium fiber laser in PPKTP and MgO∶sPPLT[J]. Optics Express, 17, 13711-13726(2009). http://www.opticsinfobase.org/abstract.cfm?uri=oe-17-16-13711

     Kumar S C, Samanta G K, Ebrahim-Zadeh M. High-power, single-frequency, continuous-wave second-harmonic-generation of ytterbium fiber laser in PPKTP and MgO∶sPPLT[J]. Optics Express, 17, 13711-13726(2009). http://www.opticsinfobase.org/abstract.cfm?uri=oe-17-16-13711

[15] Tovstonog S V, Kurimura S, Kitamura K. High power continuous-wave green light generation by quasi phase matching in MgSLT. [C]∥2007 Conference on Lasers and Electro-Optics (CLEO), May 6-11, 2007, Baltimore, MD, USA. New York: IEEE, 4452419(2007).

     Tovstonog S V, Kurimura S, Kitamura K. High power continuous-wave green light generation by quasi phase matching in MgSLT. [C]∥2007 Conference on Lasers and Electro-Optics (CLEO), May 6-11, 2007, Baltimore, MD, USA. New York: IEEE, 4452419(2007).

[16] Kang Y, Cheng L J, Yang S H et al. High power optical-carried radio frequency signal fiber power amplification[J]. Acta Photonica Sinica, 45, 0914002(2016).

     Kang Y, Cheng L J, Yang S H et al. High power optical-carried radio frequency signal fiber power amplification[J]. Acta Photonica Sinica, 45, 0914002(2016).

[17] Xie S Y, Zhang X F, Yang C L et al. Continuous-wave single-frequency 589 nm yellow laser generated from sum frequency of single-block non-planar ring cavity laser in periodically poled KTiOPO4 crystal[J]. Acta Physica Sinica, 65, 094203(2016).

     Xie S Y, Zhang X F, Yang C L et al. Continuous-wave single-frequency 589 nm yellow laser generated from sum frequency of single-block non-planar ring cavity laser in periodically poled KTiOPO4 crystal[J]. Acta Physica Sinica, 65, 094203(2016).

[18] Chen Y F, Chen Y C. Analytical functions for the optimization of second-harmonic generation and parametric generation by focused Gaussian beams[J]. Applied Physics B, 76, 645-647(2003). http://link.springer.com/article/10.1007/s00340-003-1190-y

     Chen Y F, Chen Y C. Analytical functions for the optimization of second-harmonic generation and parametric generation by focused Gaussian beams[J]. Applied Physics B, 76, 645-647(2003). http://link.springer.com/article/10.1007/s00340-003-1190-y

[19] Yarborough J M, Falk J, Hitz C B. Enhancement of optical second harmonic generation by utilizing the dispersion of air[J]. Applied Physics Letters, 18, 70-73(1971). http://scitation.aip.org/content/aip/journal/apl/18/3/10.1063/1.1653569

     Yarborough J M, Falk J, Hitz C B. Enhancement of optical second harmonic generation by utilizing the dispersion of air[J]. Applied Physics Letters, 18, 70-73(1971). http://scitation.aip.org/content/aip/journal/apl/18/3/10.1063/1.1653569

[20] Bhar G C, Chatterjee U, Datta P. Enhancement of second harmonic generation by double pass configuration in barium borate[J]. Applied Physics B, 51, 317-319(1990). http://link.springer.com/article/10.1007/BF00348966

     Bhar G C, Chatterjee U, Datta P. Enhancement of second harmonic generation by double pass configuration in barium borate[J]. Applied Physics B, 51, 317-319(1990). http://link.springer.com/article/10.1007/BF00348966