Off-axis Hybrid Three-Mirror Optical System Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional off-axis hybrid surface three-mirror optical systems are limited in their application to large field angles and small F-number scenarios, making them less effective for various optical systems requiring broader field of view and lower F-number configurations.
Innovation Solution
A method for designing an off-axis hybrid surface three-mirror optical system that involves selecting feature rays from different fields and aperture positions, calculating and fitting feature data points to obtain spherical, aspheric, and freeform surfaces, allowing for the creation of a hybrid optical system with improved optical performance across a wider range of field angles and F-numbers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional off-axis hybrid surface three-mirror optical systems are used, then the system works well for linear field of view with small field angles and large F-number, but the system cannot be effectively applied to fields of view with large field angles and small F-number
Solution Approach 1:
The patent applies local quality by using different surface types (spherical, aspheric, freeform) for different mirrors in the three-mirror system. Specifically, the primary mirror uses a spherical surface, the secondary mirror uses an aspheric surface, and the tertiary mirror uses a freeform surface. This combination allows each surface to be optimized for specific regions of the optical field, enabling the system to achieve good optical performance across large field angles and small F-numbers while maintaining manufacturability.
Solution Approach 2:
The patent employs composite materials principle by combining multiple surface types (spherical + aspheric + freeform) in a hybrid optical system. This hybrid surface three-mirror system integrates the advantages of each surface type: spherical surfaces for ease of manufacturing, aspheric surfaces for improved off-axis performance, and freeform surfaces for correcting aberrations in wide-field applications. The composite approach enables the system to meet both performance requirements and manufacturing constraints.
2Reliability
If freeform surfaces are used in optical systems, then optical performance can be optimized, but cost and processing/testing difficulty increase
Solution Approach 1:
The patent applies local quality by using different surface types (spherical, aspheric, freeform) for different mirrors in the three-mirror system. Specifically, the primary mirror uses a spherical surface, the secondary mirror uses an aspheric surface, and the tertiary mirror uses a freeform surface. This combination allows each surface to be optimized for specific regions of the optical field, enabling the system to achieve good optical performance across large field angles and small F-numbers while maintaining manufacturability.
Solution Approach 2:
The patent uses partial freeform surfaces rather than complete freeform surfaces for all mirrors. By applying freeform technology only to the tertiary mirror where it provides the most benefit, while using simpler spherical and aspheric surfaces for the primary and secondary mirrors, the system achieves improved optical performance without incurring the full cost and complexity of complete freeform implementation across all elements.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method enables the design of off-axis hybrid surface three-mirror optical systems that achieve better imaging quality, reduced RMS spot diameters, and improved modulation transfer functions, effectively expanding their applicability to larger field angles and smaller F-numbers.
Implementation Method 1
off-axis hybrid surface three-mirror optical system
Data Source
AI summary
An off-axis hybrid surface three-mirror optical system comprises a primary mirror, a secondary mirror, a tertiary mirror, and an image sensor. A reflective surface of the primary mirror is a sixth-order polynomial freeform surface of xy. A reflective surface of the secondary mirror is a sixth-order polynomial aspheric surface of xy. A reflective surface of the a tertiary mirror is a spherical surface of xy.