Membrane optics is a

flat lens A flat lens is a lens whose flat shape allows it to provide distortion-free imaging, potentially with arbitrarily-large apertures. The term is also used to refer to other lenses that provide a negative index of refraction. Flat lenses require a re ...

that employs plastic in place of glass to diffract rather than reflect or

refract In physics, refraction is the redirection of a wave as it passes from one medium to another. The redirection can be caused by the wave's change in speed or by a change in the medium. Refraction of light is the most commonly observed phenomeno ...

light. Concentric microscopic grooves etched into the plastic provide the diffraction. Glass transmits light with 90% efficiency, while membrane efficiencies range from 30 to 55%. Membrane thickness is on the order of that of plastic wrap.

Applications

MOIRE program

DARPA The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military. Originally known as the Adv ...

plans to use membrane optics as part of its Membrane Optical Imager for Real-Time Exploitation (MOIRE) program. The program uses lightweight polymer membranes for a foldable plastic orbital telescope capable of seeing a object from away. Membrane grooves range from 4 to hundreds of micrometers in width. According to DARPA, glass-based optics in satellites are reaching the point where larger mirrors exceed the lifting power of existing rockets. MOIRE is planned to be one-seventh the weight of a comparable glass-mirrored device. Individual membranes would be mounted on foldable metal petals. Once in

geostationary orbit A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitud ...

, the satellite would unfold. The membrane lens occupies one end and a sensor suite the other. The device would be the largest telescope ever built – twice the size of the ground-based twin

Keck telescope The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state In the United States, a state is a constituent political entit ...

s. It could see about 40 percent of the Earth's surface and could image a area at a resolution and generate videos at one frame per second. A ground-based prototype consists of a section of a wide device that created the first images with membrane optics.

References

External links

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Nautilus Space Telescope
Telescope types {{telescope-stub

Applications

MOIRE program

See also

References

External links