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تسجيل مستخدم جديدPerformance of Large-Format Deformable Mirrors Constructed with TNO Variable Reluctance Actuators
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Advancements in making high-efficiency actuators are an enabling technology for building the next generation of large-format deformable mirrors. The Netherlands Organization for Applied Scientific Research (TNO) has developed a new style of variable-reluctance actuator that requires approximately eighty times less power to operate as compared to the traditional style of voice-coil actuators. We present the performance results from laboratory testing of TNOs 57-actuator large-format deformable mirror from measuring the influence functions, linearity, hysteresis, natural shape flattening, actuator cross-coupling, creep, repeatability, and actuator lifetime. We measure a linearity of 99.4 +- 0.33% and hysteresis of 2.10 +- 0.23% over a stroke of 10 microns, indicating that this technology has strong potential for use in on-sky adaptive secondary mirrors (ASMs). We summarize plans for future lab prototypes and ASMs that will further demonstrate this technology.
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