Due to an ever growing shortage of conventional energy sources, there is an increasingly intense interest in harnessing solar energy. The instant invention can contribute to the goal of achieving environmentally clean solar energy to be competitive with conventional energy sources. Method and apparatus are presented for coupling to a transparent sheet with an embedded array of preformed or formable mirrored micro-balls for use in a solar energy concentrator, and functionally similar applications such as optical switches and solar rocket assist. Mirrored micro-balls and particulate formable mirrors in cells are covered with a thin spherical shell of lubricating liquid so that they are free to rotate in an almost frictionless encapsulation in the sheet. Induced polarization electric or magnetic dipoles in the mirrors provide a method of controlling the alignment of the mirrored balls. Electrophoretically and magnetophoretically forming mirrors in situ on a rigid surface in a rotatable cell are also disclosed. Confining the balls and cells in cavities within a single sheet, rather than loosely between two sheets, allows for greater alignment accuracy which is needed for higher concentrations with gains greater than 10.times.. Immersing balls and cells in a lubricating fluid permits nearly frictionless rotation which reduces the power requirement for rotation, and further enables greater alignment accuracy as the impediment of unnecessary friction need not be overcome.