Light is delivered to the Earth’s surface directly from the sun with a density of about 1.361 kW/m². An optic pair deployed in space delivers that light to any point on Earth at any time of day with the ability to control the area over which it is delivered. The system can be used to illuminate large areas of the Earth at night over a large delivery area (e.g. for support to humanitarian relief operations), or to concentrate that energy in a small area for destructive purposes.
The primary optic is a Fresnel lens with adaptive focal length. It is approximately 2km in diameter (approx. 3GW power collection area), and located at Lagrange point 1 (L1), between the Earth and the Sun. The lens is comprised of a transparent, lightweight stretchable elastomer composite. The lens is deployed in a small package launched from the Earth’s surface. Upon reaching L1, the inflatable framework deploys, stretching the lens to its final dimensions. The lens focal length is changed by changing the geometry of the Fresnel lens elements by deforming them with strong electric fields. The deformation results from Maxwell pressure. Since this type of operation requires a high voltage, but only minimal current (it is essentially a deformable capacitor), the power draw of the system is small, and can be supplied with solar cells.
The secondary optic is a reflector, and also has an adaptive focal length, controllable by electric field. The secondary optic is in either low Earth orbit (LEO), or in geosynchronous orbit. The secondary optic receives the focused light from the primary lens, and redirects it at the surface, with adaptable spot delivery area.