A NEW MEMBRANE MIRROR FOR INFRARED TELESCOPES

摘要

A new membrane mirror is capable of imaging in the infrared and visible for astronomical imaging. The development of the membrane mirror has the order-of-magnitude aperture size increase or weight reduction for large aperture ground based telescopes. The membrane mirror is reproducible at a fraction of the time and cost as compared to glass equivalent size. It also requires a considerable mass and cost reduction of the telescope mount as compared to conventional size equivalent mounts. The membrane mirror has overcome the problems of near edge distortion when stretched that has been a limiting factor until now. Further more, the surface problem of having an oblate spheroid has been overcome now by deepening the centre thereby creating a parabola through active central distortion of the figure. Because there is no active system to produce pattern surface distortion, the ratio of thickness and size has resulted in a stable surface with diffraction limited results in the infrared. Research is continuing on to develop an upgradeable mirror with visible range diffraction limited results. A unique interesting feature of the mirror for astronomy is optional variable focal or N focal lengths. Because it is used as a direct imager focussing can also be accomplished through precision vacuum control. This unique adaptability of the mirror creates multiple telescope applications. Another interesting feature is the option of using the mirror as an off axis system in a telescope. An example of this configuration is in a Gregorian system.