I have a conceptual design for a Cassegrain paraboloid main mirror for a space telescope that is 3000 meters (32,808 feet) in diameter. Grand schemes are kindof a hobby of mine. Anyway...

The structure is in orbit. It has a single truss running coincident with the optical axis, through the 'vertex' of the mirror. A second hoop truss runs the circumference of the main mirror. From far away it has the appearance of a gyroscope. A thin highly reflective film (mirror) is held loosely in position by the hoop, which is attached to the central truss by guy wires. A bank of lasers on both sides of the mirror project beams that are reflected off dual disco balls on hyperfast rotating spindles, illuminating every square centimeter of the mirror on both sides. The resulting radiation pressure deforms the thin film mirror into a paraboloid, via the equation:

P = phi/c

where,
phi = energy flux
c = speed of light

Dual projectors provide opposing pressures to both sides of the film, and with a complementary rangefinding system controls the radiation gradient and shape to high precision. At equilibrium the mirror has a "VAST" light collection area. lol.

Neat idea, I think.