摘要
为了研究大气湍流变化对多孔径光学系统成像质量的影响,针对Golay3结构建立了一个理论分析模型,推导了湍流影响下望远系统的点扩散函数(point spread function, PSF)的表达式。分别针对近似圆形和近似长条状分布的湍流结构对成像特性的影响进行了讨论,具体构建了两种湍流影响下的光场相位计算模型,并计算比较了两种湍流的调制传递函数(modulation transfer function, MTF)。结果表明,光路中存在湍流将导致系统成像质量下降。在近似圆形湍流中,湍流强度越小,系统MTF影响越小。不同强度湍流影响的MTF在归一化空间频率0.16、0.45和0.69处均下降0.05左右。在近似长条状湍流中,对流湍流风速越小,系统MTF影响越小。不同风速的湍流影响的MTF在空间频率0.16、0.42和0.69处分别下降0.25、0.09和0.05左右。比较两种湍流表明,近似长条状湍流对成像系统MTF影响更为明显。
In order to study the influence of atmospheric turbulence on the imaging quality of multi-aperture optical system, a theoretical analysis model was established for the Golay3 structure. The expression of point spread function(PSF) and modulation transfer function(MTF) of this structure were derived. To discuss the influence of similar circular and elongated turbulence structures on the imaging characteristics, the MTF under two turbulence conditions were calculated and compared, and the phase calculation models were constructed. The results show that when there is presence of turbulence in the optical path, the image quality of the system will decrease. As for similar circular turbulence, the smaller the intensity of turbulence is, the less the impact on the MTF is. Specially, the MTF affected by turbulence of different intensities decreases by about 0.05 at the normalized spatial frequencies of 0.16, 0.45, and 0.69. As for similar elongated turbulence, the smaller turbulent wind speed is, the less the impact on the MTF is. The MTF affected by turbulence of different wind speeds decreases by about 0.25, 0.09, and 0.05 at the spatial frequencies of 0.16, 0.42, and 0.69, respectively. The comparison of the influence of the two turbulences on the system shows that the similar elongated turbulence has a more obvious influence on the MTF.
作者
刘婷
唐善发
刘何伟
钱俊宏
张蓉竹
Liu Ting;Tang Shanfa;Liu Hewei;Qian Junhong;Zhang Rongzhu(School of Electronics and Information Engineering,Sichuan University,Chengdu 610064,China)
出处
《红外与激光工程》
EI
CSCD
北大核心
2021年第12期497-504,共8页
Infrared and Laser Engineering
基金
四川省重大科学仪器设备专项(2019ZDZX0038)。
关键词
湍流变化
多孔径成像
点扩散函数
调制传递函数
turbulence changes
multi-aperture imaging
point spread function
modulation transfer function
