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随着水下光通信、传感和激光雷达等应用的发展,研究水下光学系统成像特性具有重要意义.本文研究了海洋湍流对自适应光学成像系统特征参量(如Strehl比、Greenwood时间常数和等晕角)的影响.推导出了海洋湍流中短曝光成像Strehl比的近似解析表达式,并证明:除了在近场DG/r0=1附近外(DG和r0分别为光学系统的光瞳直径和海洋湍流中可见参数),该近似公式均可保证足够的精度.此外,还得到了海洋湍流中Greenwood时间常数和等晕角的表达式.研究表明:随着海水盐度变化引起的海洋湍流逐渐占主导地位时,这三个特征参量值均减小;随着海水湍流动能耗散率的减小或海水湍流温度方差耗散率的增大,这三个特征参量值也均减小.本文研究结果对工作于水下湍流环境中自适应光学成像系统应用具有理论参考意义.
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关键词:
- 海洋湍流 /
- Strehl比 /
- Greenwood时间常数 /
- 等晕角
Since recently one is interested in underwater communications, imaging, sensing and lidar appeared, it is important to study characteristic parameters of the adaptive optical imaging system in oceanic turbulence. Until now, the characteristic parameters of the adaptive optical imaging system in atmospheric turbulence have investigated widely and in depth, but those in oceanic turbulence have been examined seldom. It is known that the atmospheric turbulence is induced by the temperature fluctuation. However, the oceanic turbulence is induced by both the temperature fluctuation and the salinity fluctuation. The temperature and salinity spectra have similar ''bumped'' profiles, with bumps occurring at different wave numbers. Thus, the behavior of light propagation in oceanic turbulence is very different from that in atmospheric turbulence. In this paper, the influence of oceanic turbulence on characteristic parameters (i.e., strehl ratio, Greenwood time constant, and isoplanatic>) of the adaptive optical imaging system is studied. The approximate analytical expression of the Strehl ratio for the short-exposure imaging case is derived. It is demonstrated by the numerical calculation method that this Strehl ratio approximate expression is accurate enough except the near field when DG/r0=1 (where DG is the pupil diameter of the optical system, r0 is the seeing parameter in oceanic turbulence), and the relative error maximum of this Strehl ratio approximate expression in the far field is much smaller than that in the near field. In addition, the analytical expressions of the Greenwood time constant and the isoplanatic> in oceanic turbulence are also obtained in this paper. It is shown that the values of the three characteristic parameters (i.e., Strehl ratio, the Greenwood time constant and the isoplanatic>) decrease when salinity-induced optical turbulence dominates gradually. The Strehl ratio, the Greenwood time constant and the isoplanatic> also decrease as the rate of dissipation of kinetic energy per unit mass of seawater decreases or the rate of dissipation of mean-squared temperature increases. It is known that the isoplanatic> at wavelength λ=0.5 μm are roughly 7-10 μrad for a nearly vertical path from Earth to space in atmospheric turbulence. However, it is shown in this paper that the isoplanatic> may be on the order of μrad after 100 m propagation distance in oceanic turbulence. Therefore, the influence of oceanic turbulence on the isoplanatic> is very large. The results obtained in this paper will be useful in the applications of adaptive optics imaging systems involving oceanic turbulence channels.-
Keywords:
- oceanic turbulence /
- Strehl ratio /
- Greenwood time constant /
- isoplanatic>
[1] Guo Y M, Rao C H, Bao H, Zhang A, Wei K 2014 Acta Phys. Sin. 63 149501 (in Chinese) [郭友明, 饶长辉, 鲍华, 张昂, 魏凯 2014 物理学报 63 149501]
[2] Booth M J 2014 Light-Sci. Appl. 3 e165
[3] Miller D T, Kocaoglu O P, Wang Q, Lee S 2011 Eye 25 321
[4] Jiang W H 2006 Chin. J. Nature 28 7 (in Chinese) [姜文汉 2006 自然杂志 28 7]
[5] Andrews L C, Phillips R L 2005 Laser Beam Propagation through Random Media (2nd Ed.) (Bellingham, WA: SPIE Optical Engineering Press) pp606–623
[6] Mahajan V N 2005 J. Opt. Soc. Am. A 22 1824
[7] Chen T J, Zhou W C, Wang F, Huang D Q, Lu Y H, Zhang J Z 2015 Acta Phys. Sin. 64 134207 (in Chinese) [陈天江, 周文超, 王峰, 黄德权, 鲁燕华, 张建柱 2015 物理 学报 64 134207]
[8] Zong F, Qiang X W, Wu M, Chang J Y, Feng S L 2014 Acta Opt. Sin. 34 16 (in Chinese) [宗飞, 强希文, 吴敏, 常金勇, 封双连 2014 光学学报 34 16]
[9] Fusco T, Conan J M 2004 J. Opt. Soc. Am. A 21 1277
[10] Greenwood D P 1977 J. Opt. Soc. Am. 67 390
[11] Qu Q, Cao Z L, Hu L F, Zhang H S, Zhao J L, Xuan L 2015 Chin. Opt. 8 121 (in Chinese) [瞿青, 曹召良, 胡立 发, 张红胜, 赵晶丽, 宣丽 2015 中国光学 8 121]
[12] Loos G C, Hogge C B 1979 Appl. Opt. 18 2654
[13] Ding X K, Rong J, Bai H, Wang X, Shen J E, Li F 2008 Chin. Opt. Lett. 6 1
[14] Yu L K, Xu J, Hong S, Hou Z H, Yi W 2014 Opt. Lett. 39 789
[15] Yu L K, Hou Z H, Zhang S C, Xu J, Yi W 2015 Opt. Eng. 54 024105
[16] Bogucki D J, Domaradzki J A, Ecke R E, Truman C R 2004 Appl. Opt. 43 5662
[17] Hou W L, Woods S, Jarosz E, Goode W, Weidemann A 2012 Appl. Opt. 51 2678
[18] Nikishov V V, Nikishov V I 2000 Int. J. Fluid Mech. Res. 27 82
[19] Lu L, Ji X L, Baykal Y 2014 Opt. Express 22 027112
[20] Pu H, Ji X L 2016 J. Opt. 18 105704
[21] Lu W, Liu L, Sun J 2006 J. Opt. A: Pure Appl. Opt. 8 1052
[22] Hill R J 1978 J. Fluid Mech. Res. 88 541
[23] Hill R J 1978 J. Opt. Soc. Amer. 68 1067
[24] Korotkova O, Farwell N, Shchepakina E 2012 Wave Random Complex 22 260
[25] Tang M M, Zhao D M 2013 Appl. Phys. B 111 665
[26] Baykal Y 2016 Opt. Commun. 375 15
[27] Yang T, Ji X L, Li X Q 2015 Acta Phys. Sin. 64 204206 (in Chinese) [杨婷, 季小玲, 李晓庆 2015 物理学报 64 204206]
[28] Liu Y X, Chen Z Y, Pu J X 2017 Acta Phys. Sin. 66 124205 (in Chinese) [刘永欣, 陈子阳, 蒲继雄 2017 物理学报 66 124205]
[29] Ma X L 2015 Acta Photon. Sin. 44 0601003 (in Chinese) [马雪莲 2015 光子学报 44 0601003]
[30] Fried D L 1966 J. Opt. Soc. Am. 56 1372
[31] Fried D L 1990 J. Opt. Soc. Am. A 7 1224
[32] Baykal Y 2016 Appl. Opt. 55 1228
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[1] Guo Y M, Rao C H, Bao H, Zhang A, Wei K 2014 Acta Phys. Sin. 63 149501 (in Chinese) [郭友明, 饶长辉, 鲍华, 张昂, 魏凯 2014 物理学报 63 149501]
[2] Booth M J 2014 Light-Sci. Appl. 3 e165
[3] Miller D T, Kocaoglu O P, Wang Q, Lee S 2011 Eye 25 321
[4] Jiang W H 2006 Chin. J. Nature 28 7 (in Chinese) [姜文汉 2006 自然杂志 28 7]
[5] Andrews L C, Phillips R L 2005 Laser Beam Propagation through Random Media (2nd Ed.) (Bellingham, WA: SPIE Optical Engineering Press) pp606–623
[6] Mahajan V N 2005 J. Opt. Soc. Am. A 22 1824
[7] Chen T J, Zhou W C, Wang F, Huang D Q, Lu Y H, Zhang J Z 2015 Acta Phys. Sin. 64 134207 (in Chinese) [陈天江, 周文超, 王峰, 黄德权, 鲁燕华, 张建柱 2015 物理 学报 64 134207]
[8] Zong F, Qiang X W, Wu M, Chang J Y, Feng S L 2014 Acta Opt. Sin. 34 16 (in Chinese) [宗飞, 强希文, 吴敏, 常金勇, 封双连 2014 光学学报 34 16]
[9] Fusco T, Conan J M 2004 J. Opt. Soc. Am. A 21 1277
[10] Greenwood D P 1977 J. Opt. Soc. Am. 67 390
[11] Qu Q, Cao Z L, Hu L F, Zhang H S, Zhao J L, Xuan L 2015 Chin. Opt. 8 121 (in Chinese) [瞿青, 曹召良, 胡立 发, 张红胜, 赵晶丽, 宣丽 2015 中国光学 8 121]
[12] Loos G C, Hogge C B 1979 Appl. Opt. 18 2654
[13] Ding X K, Rong J, Bai H, Wang X, Shen J E, Li F 2008 Chin. Opt. Lett. 6 1
[14] Yu L K, Xu J, Hong S, Hou Z H, Yi W 2014 Opt. Lett. 39 789
[15] Yu L K, Hou Z H, Zhang S C, Xu J, Yi W 2015 Opt. Eng. 54 024105
[16] Bogucki D J, Domaradzki J A, Ecke R E, Truman C R 2004 Appl. Opt. 43 5662
[17] Hou W L, Woods S, Jarosz E, Goode W, Weidemann A 2012 Appl. Opt. 51 2678
[18] Nikishov V V, Nikishov V I 2000 Int. J. Fluid Mech. Res. 27 82
[19] Lu L, Ji X L, Baykal Y 2014 Opt. Express 22 027112
[20] Pu H, Ji X L 2016 J. Opt. 18 105704
[21] Lu W, Liu L, Sun J 2006 J. Opt. A: Pure Appl. Opt. 8 1052
[22] Hill R J 1978 J. Fluid Mech. Res. 88 541
[23] Hill R J 1978 J. Opt. Soc. Amer. 68 1067
[24] Korotkova O, Farwell N, Shchepakina E 2012 Wave Random Complex 22 260
[25] Tang M M, Zhao D M 2013 Appl. Phys. B 111 665
[26] Baykal Y 2016 Opt. Commun. 375 15
[27] Yang T, Ji X L, Li X Q 2015 Acta Phys. Sin. 64 204206 (in Chinese) [杨婷, 季小玲, 李晓庆 2015 物理学报 64 204206]
[28] Liu Y X, Chen Z Y, Pu J X 2017 Acta Phys. Sin. 66 124205 (in Chinese) [刘永欣, 陈子阳, 蒲继雄 2017 物理学报 66 124205]
[29] Ma X L 2015 Acta Photon. Sin. 44 0601003 (in Chinese) [马雪莲 2015 光子学报 44 0601003]
[30] Fried D L 1966 J. Opt. Soc. Am. 56 1372
[31] Fried D L 1990 J. Opt. Soc. Am. A 7 1224
[32] Baykal Y 2016 Appl. Opt. 55 1228
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