Pupil Relay Field of View Switch for Optical Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical systems face challenges in switching between narrow and wide fields of view without altering the aperture size, which affects sensitivity and efficiency, especially when combining active and passive imaging systems.
Innovation Solution
A compact internal field of view switch using a pupil relay with non-unity magnification, implemented between the exit aperture and the active imaging sub-system, allows for switching between narrow and wide fields of view while maintaining a constant aperture size, utilizing a five-mirror all-reflective configuration and Cassegrain telescopes to relay the beam between pupils.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If field of view switching is provided within the afocal telescope or imager, then field of view can be switched between narrow and wide, but the aperture size must change which reduces sensitivity in wide field of view configuration
Solution Approach 1:
An all-reflective five-mirror pupil relay with non-unity magnification is introduced as an intermediary optical system between the afocal telescope and the imager. This pupil relay enables field of view switching while maintaining a constant exit aperture size, thereby preserving sensitivity in wide field of view configuration. The pupil relay acts as a mediator that decouples the field of view switching function from the aperture size change that previously accompanied it.
2Adaptability or versatility
If aperture size is reduced for wide field of view configuration, then field of view can be widened, but sensitivity is reduced
Solution Approach 1:
The invention changes the magnification parameter of the pupil relay to achieve field of view switching. By using non-unity magnification in the five-mirror pupil relay, the system can switch between narrow and wide field of view configurations while maintaining a constant exit aperture size, thereby preserving sensitivity across different field of view settings.
3Reliability
If fixed wide field of view focal length is designed, then sensitivity can be maintained, but field of view switching capability is lost
Solution Approach 1:
The invention introduces a dynamic field of view switching mechanism using an all-reflective five-mirror pupil relay with non-unity magnification. This dynamic system allows the optical system to switch between narrow and wide field of view configurations while maintaining a constant exit aperture size, thereby preserving sensitivity while gaining field of view switching capability.
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
This solution enables dual field of view capability without sacrificing received energy or aperture size, maintaining full-aperture efficiency and compatibility with multi-wavelength operations like LADAR and infrared imaging.
Implementation Method 1
a field of view switching mechanism positioned between the exit aperture and the active imaging sub-system, the field of view switching mechanism configured as a pupil relay having non-unity magnification... In one example the field of view switching mechanism is an all-reflective, five mirror pupil relay
Implementation Method 2
the field of view switching mechanism includes a pair of Cassegrain telescopes disposed on either side of a flat fold mirror, and is configured to relay the laser beam between first and second pupils located opposite one another
Data Source
AI summary
An optical system incorporating a compact internal field of view switch configured to switch the field of view of the optical system between a narrow field of view and a wide field of view while maintaining a constant exit aperture size. In one example the optical system includes an active imaging sub-system optically coupled to the exit aperture, and the field of view switch is positioned between the exit aperture and the active imaging sub-system. In one example the field of view switch is configured as a pupil relay having non-unity magnification.