Novel design methodology proposed for reflective optical system with low tilt-error sensitivity

Characterized by giant aperture and lengthy focal size, the reflective optical system has the benefits of small variety of optical components and easy optical construction. But the intrinsic aberration and the misalignment derived aberration improve exponentially with the rise of focal size and aperture, leading to a major degradation of the optical system imaging high quality attributable to only a small quantity of misalignment.

In a research revealed in Optics Express, Prof. Meng Qingyu and his Doctoral scholar Qin Zichang from Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP) of the Chinese Academy of Sciences (CAS) proposed a complete reflective optical system design methodology with low tilt error sensitivity. This methodology not solely optimizes the imaging efficiency of the system and controls the lean error sensitivity of the optical system, but additionally considers the uniformity of the sensitivity of every mirror of the system.

Using the tactic of geometric optics, the researchers established the mathematical evaluation fashions of single-mirror system and two-mirror system. Through the theoretical derivation of the connection between the number of optical path distinction (OPD) attributable to the lean of optical system and the parameters of optical system, they concluded that the system with giant incidence angle has higher number of OPD and better sensitivity when the lean error utilized, and the tangent slope on the intersection of ray and mirror is the important thing issue to find out the error sensitivity of optical system.

Based on the above discovering, the researchers proposed the analysis perform S of tilt error sensitivity of optical system, and established a desensitization design methodology of reflective optical system. Taking an off-axis three-mirror optical system with a focal length of 100mm and an F-number of 5 as examples, they in contrast the lean error sensitivity of the 2 programs earlier than and after the desensitization design through the use of the proposed methodology. The outcomes confirmed that this methodology is efficient.