对红外光学系统的中心偏差开展分析,构建中心偏差分析流程,并提出相应的装调方法。首先,对红外光学系统的中心偏差的成因初步解构为光学元件的子午和弧矢方向的倾斜变化与平移变化,并将该变化量通过公差的形式,与光学性能指标——调制...对红外光学系统的中心偏差开展分析,构建中心偏差分析流程,并提出相应的装调方法。首先,对红外光学系统的中心偏差的成因初步解构为光学元件的子午和弧矢方向的倾斜变化与平移变化,并将该变化量通过公差的形式,与光学性能指标——调制传递函数(Modulation Transfer Function,MTF)以及光轴漂移量建立关系,得到各光学元件公差引起的空间姿态与理想系统光轴之间的差异,并根据差异的大小,评估各光学元件对MTF的贡献度以及对系统光轴的影响程度,建立各光学元件的灵敏度表。根据各光学元件的灵敏度结果,以系统指标要求的光轴漂移量为分析点,利用蒙特卡罗(Monte Carlo)计算引擎对各光学元件以及组件的各种姿态组合进行计算,得出光学元件在满足指标要求下的公差限。根据以上的分析结果,提出基于光轴偏移校正和光学元件位置调整的调校方法,该方法利用中心偏测量仪实时监测敏感元件的中心偏差,并通过有效的光轴偏移校正和元件位置调整,使光学系统的中心对准光轴。通过实验验证,证明了该调校方法能够有效减小中心偏差,提高红外光学系统的性能和图像质量。展开更多
The physical meaning and essence of Fresnel numbers are discussed,and two definitions of these numbers for offaxis optical systems are proposed.The universal Fresnel number is found to be N =(a2/λz) * C1+ C2.The Rayl...The physical meaning and essence of Fresnel numbers are discussed,and two definitions of these numbers for offaxis optical systems are proposed.The universal Fresnel number is found to be N =(a2/λz) * C1+ C2.The Rayleigh–Sommerfeld nonparaxial diffraction formula states that a simple analytical formula for the nonparaxial intensity distribution after a circular aperture can be obtained.Theoretical derivations and numerical calculations reveal that the first correction factor C1 is equal to cos θ and the second factor C2 is a function of the incident wavefront and the shape of the diffractive aperture.Finally,some diffraction phenomena in off-axis optical systems are explained by the off-axis Fresnel number.展开更多
文摘对红外光学系统的中心偏差开展分析,构建中心偏差分析流程,并提出相应的装调方法。首先,对红外光学系统的中心偏差的成因初步解构为光学元件的子午和弧矢方向的倾斜变化与平移变化,并将该变化量通过公差的形式,与光学性能指标——调制传递函数(Modulation Transfer Function,MTF)以及光轴漂移量建立关系,得到各光学元件公差引起的空间姿态与理想系统光轴之间的差异,并根据差异的大小,评估各光学元件对MTF的贡献度以及对系统光轴的影响程度,建立各光学元件的灵敏度表。根据各光学元件的灵敏度结果,以系统指标要求的光轴漂移量为分析点,利用蒙特卡罗(Monte Carlo)计算引擎对各光学元件以及组件的各种姿态组合进行计算,得出光学元件在满足指标要求下的公差限。根据以上的分析结果,提出基于光轴偏移校正和光学元件位置调整的调校方法,该方法利用中心偏测量仪实时监测敏感元件的中心偏差,并通过有效的光轴偏移校正和元件位置调整,使光学系统的中心对准光轴。通过实验验证,证明了该调校方法能够有效减小中心偏差,提高红外光学系统的性能和图像质量。
基金supported by the National Natural Science Foundation of China(Grant Nos 61205212,11104296 and 61205210)
文摘The physical meaning and essence of Fresnel numbers are discussed,and two definitions of these numbers for offaxis optical systems are proposed.The universal Fresnel number is found to be N =(a2/λz) * C1+ C2.The Rayleigh–Sommerfeld nonparaxial diffraction formula states that a simple analytical formula for the nonparaxial intensity distribution after a circular aperture can be obtained.Theoretical derivations and numerical calculations reveal that the first correction factor C1 is equal to cos θ and the second factor C2 is a function of the incident wavefront and the shape of the diffractive aperture.Finally,some diffraction phenomena in off-axis optical systems are explained by the off-axis Fresnel number.
