The individual autonomous flyers building up the cloud of sunshades are proposed not to reflect the sunlight but rather to be transparent lenses, deflecting the light slightly so it does not hit Earth. This minimizes the effect of on the units, requiring less effort to hold them in place at the L1 point. An optical prototype has been constructed by with funding from .
One proposed such sunshade for use towards that effect would be composed of 16 trillion small disks at the Sun-Earth L1 , 1.5 million kilometers above Earth. Each disk is proposed to have a 0.6-meter diameter and a thickness of about 5 micrometers. The mass of each disk would be about a gram, adding up to a total of almost 20 million tonnes. Such a group of small sunshades that blocks 2% of the sunlight, deflecting it off into space, would be enough to halt global warming, giving us ample time to cut our emissions back on earth.
Such a group of sunshades would need to occupy an area of about 3.8 million square kilometers if placed at the L1 point. The deployment of the flyers is an issue that requires new technology. It has been proposed that this would be accomplished most easily with large or firing a capsule containing a million shades into space every 5 minutes for 10 years using 20 separate launch sites.
Even so, it would still take years to launch enough of the disks into to have any effect. Thus, if this technology should become essential, enough time would be needed to implement it. Roger Angel of the University of Arizona presented the idea for a sunshade at the in April 2006 and won a Institute for Advanced Concepts grant for further research in July 2006.