The constantly increasing needs for astronomical imaging of ever fainter objects as well as for imaging the Earth from space require much higher angular resolution and dynamic range than current optical telescopes can deliver. Mirrors are the key elements of these systems; but they are technologically difficult to improve because they must maintain an exceedingly precise shape while resisting deformations (for example from gravity and/or variable wind loads) in the open environments in which they must operate. Our interdisciplinary novel technology will establish a new paradigm: we will shape thin, very smooth, “fire-polished,” lightweight glass to a predetermined curvature and generate dynamically controlled stiffness by using the addressable energy of electroactive polymers (EAPs) to resist environmental deformations – making what we call a “Live” Mirror.
LiveMetaOptics presented the Exo-life finder (ELF) telescope combined with the hybrid dynamic structure of live and light active mirror named as “Live-mirror”. Recently we reported the idea of active optical surface correction using the advantage of an electromechanical stimulator to deform mirror surface in a significant correction scale. An effort to develop a conventional electroactive polymer (EAP) actuator through Live-mirror application has been taken the new approach, assembling EAP actuator via additive manufacturing or 3D printing technology. The approach of next-generation mirror leaned on 3D printing technological advancement is able to unlock the principles of a potentially new actuator manufacturing technique. Full 3D print of modified EAP was formulated with plasticized terpolymer for an active layer and terpolymer/CB composite for printed electrodes. Though rudimentary of electroactive polymer, the full-printed actuator could transfer its transversal stress or shear force to shape the mirror surface under low applied electric fields. We described here as well creating multilayer structures with capabilities well beyond those of the individual actuator components. Our various configurations of printed actuators could achieve glass surface deformation in a range of 50 nm to 2 µm considering the maximum glass deformation. As a result of material modification coupled with 3D printing technology, we can increase productivity while enabling a mass and cost reduction and an increase of the parts functionality in terms of the real application.
Optical communication and remote sensing (on the ground and in space) including astronomy requesting high-dynamic range observations are the next frontiers in high-bandwidth communication and civil space surveillance technologies. Each requires very precise glass mirror technology, which has not kept pace with corresponding optical and infrared sensor advances. Consequently communication and remote sensing systems are currently limited by the cost and manufacturing restrictions of their high-quality optics. We are developing a new and interdisciplinary technology for creating extremely lightweight diffractionlimited meta-material-based optical systems with exceptional optical quality spectacularly lower cost and production time — Live-Mirror. Notably such new technology is crucial to the development of dedicated high angular resolution and high-contrast telescope concept – The ExoLife Finder (ELF) Telescope – to the exoplanets studies and related science such as detecting life and even civilizations on Earth-like planets.
The novelty of correcting optical mirrors surface in a few microns of the desired precisely-shaped are supported by electroactive polymer actuating/sensing devices. The P(VDF-TrFE-CFE) terpolymer with the 10 % DINP plasticizer has field as EAP which showed 10 times higher in longitudinal strain with respect to the neat one and the increase of total axial strain from 0.4 % - 3.0 % with the multilayer sample 1 to 8 layers respectively. The actuator stack was integrated to the mirror in order to prove the concept of adaptive mirror which is able to reach to goal of a few micron mirror deformation.
Currently planned massively segmented telescopes like the European Extremely Large Telescope (EELT)1 or the Thirty Meter Telescope (TMT)2, use “Keck-era” optics. Their mirror subapertures create a dynamically rigid primary optical surface from 100’s of 1m-scale few-cm thick mirrors. We suggest that a dedicated telescope for distinguishing reflected exoplanet light from its host star may not follow these design principles. To reduce moving mass and telescope-scattered light, a post-Keck era large telescope could use new technologies that replace this opto-mechanical stiffness with massively parallel active electro-optics and interferometric concepts. This opens the intriguing possibility of building a dedicated ground-based exoplanet telescope with an aperture of 20m at a cost-scale of $100M. This is a compelling reason for exploring what we call “synthetic aperture” or “hybrid optical telescopes.” Even larger apertures that could be an order of magnitude less costly per square meter than comparable Keck-like optics are possible. Here we consider an optical system built from a relatively “floppy” optical structure and scalable interferometrically phased, moderate size (5m diameter), subapertures. This ExoLife Finder (ELF) telescope is sensitive to optical biomarker signals and has the power to map the surfaces of nearby M-dwarf exoplanets on subcontinental scales.
The exponential growth in exoplanets studies and related science such as detecting life and even civilizations on Earth-like planets requires high angular resolution and high-contrast observations. Such appealing sciences cases are a powerful reason for developing a dedicated high contrast telescope concept – The ExoLife Finder (ELF) Telescope. Here we describe the ELF overall optical concept, its preliminary Adaptive Optics concept and a novel and revolutionary technology to produce mirrors making use of force-sensor-actuator elements that are 3D-printed onto very thin slumped glass-sandwich elements of fire-polished glass – a very precise aspherical optical surface dedicated to high contrast measurements.
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