Construction of a compact off-axis three-mirror reflective system.

Area of Science:

• Optical Engineering
• Optics Design

Background:

• Off-axis reflective optical systems offer miniaturization and no obscuration benefits.
• Controlling system structure during design and optimization, especially for compactness, is challenging.

Purpose of the Study:

• To propose a novel constructing method for off-axis reflective optical systems that ensures a compact system structure.
• To combine aberration constraints with system structure constraints for effective design.

Main Methods:

• Utilizing a genetic algorithm to simultaneously optimize multiple parameters, including aberration (optical performance) and mirror coordinates (system structure).
• Developing an initial structure that is compact and unobscured, facilitating subsequent optimization.
• Designing a compact off-axis three-mirror reflective system using XY polynomial representation for each mirror.

Main Results:

• The proposed method successfully generates a compact and unobscured initial structure for off-axis reflective optical systems.
• A specific compact off-axis three-mirror system was designed with a 90 mm entrance pupil diameter, 405 mm focal length, and a 3°x3° field of view.
• Optimized optical performance was achieved through XY polynomial mirror descriptions.

Conclusions:

• The combined optimization of aberration and system structure using a genetic algorithm is an effective strategy for designing compact off-axis reflective optical systems.
• The developed method simplifies the optimization process and leads to practical, miniaturized optical designs.