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This paper summarizes concept studies for a large telescope capable of wide-field imaging and of the highest possible dynamic range for photometry and angular resolution.Point-spread functions (PSFs) and scattered light levels at large offsets are computed and compared for four telescopes of the same light-gathering power but with different pupil functions:1. a reference monolithic mirror telescope with a 17.4 m primary, 2. a segmented mirror telescope (SMT) with a hexagonally segmented primary, 3. a hexagonal off-axis telescope (HOT) with a distributed aperture made of m unobstructed circular 6 # 6.5 mirrors that are identical off-axis sections of a parent 20 m mirror, and 4. a square off-axis telescope (SOT) whose aperture is made of m off-axis mirrors. 4 # 8The characteristics of the PSFs are examined in the diffraction-and seeing-limited regimes, assuming (1) perfect mirror figure and (2) realistic figure errors (edge defects). The implications of field rotation with an altitude-azimuth mounting are discussed in each case. The implementation of adaptive optics (AO) and the properties of AO-compensated PSFs having a Strehl ratio of 0.5, and of coronagraphic imaging, are also discussed for the four configurations. It is shown that, in the seeing-limited regime and as intuitively expected, the optical performance of all four telescopes is comparable. With higher order adaptive optics and for coronagraphic observations, the SOT and HOT are superior to the SMT. This distinction becomes larger with relaxed constraints on mirror edge-polishing requirements. A full optical design is presented for the novel HOT configuration, and optical fabrication issues are briefly addressed. Finally, science programs and possible instrumentation layouts with the HOT are briefly explored for different modes of operation. It appears that the natural "optical bench" configuration of the HOT can provide a remarkably versatile and convenient environment for instrument deployment.

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high-bandwidth communication, civil space surveillance technologies, wireless optical communication systems (UV and free-space systems), hyper-aperture multimirror structures, geoengineering (space mirror), and astronomical systems. [1,2] In particular the light-gathering power of an optical telescope, its "light grasp" or aperture gain, is one of the most important features of a telescope, [3] which requires very precise glass mirror technology.Recently, we have proposed a "World's Largest Telescope" for achieving highcontrast observations that could use this technology. [4][5][6] Such an optical system will be limited by the cost and manufacturability of large mirrors. The work described here, optics fabricated from an optimized electroactive polymer (EAP), could enable optics like these. The new approach will extend conventional active mirror technologies to larger smooth optical surfaces, without abrasive polishing. This means it will be possible to create precisely shaped low scattered light mirrors-suitable to astronomical applications-faster and at lower production costs. Our long-term vision for the new technology is to decrease the mass density (and cost) of mirrors by an order of magnitude.The idea of using force actuator-sensors fabricated from EAPs [3,4] is developed in this work in order to achieve active mirror surface shape control. By manipulating EAPs as active supports, integrated into the mirror structure allows correcting the mirror shape with a continuous actuator force distribution. Figure 1 illustrates how EAPs behave as elastic electromechanical deforming springs. This "electrical polishing" can correct surface shape errors that would be conventionally removed by abrasive grinding. To achieve high optical mirror quality surfaces with a thickness of a few millimeters the EAP glass deformation must have a dynamic range of few microns corresponding to actuator forces of about 1 N. The technique we propose could potentially be achieved using only additive manufacturing via 3D-printing technology.In this article we aim to present the EAP concept for Live-Mirror active optics. We evaluate different polymers in specific actuator designs in order to test their mechanical actuation properties for mirror-actuator prototypes. This article focuses on EAP-based actuator basic properties. Future work will explore how EAP sensors can be integrated into mirror systems.