Abstract: The present invention is directed to systems, devices and methods utilizing a proxy device that indicates directional aspects of redirected light from a corresponding light redirecting element by the position of one or more redirected light beams in one or more directions or coordinates on such a proxy device. The position characteristics of light redirected from the proxy device correlate to the aim of the light redirecting element associated with the proxy. This allows the proxy information to be used to accurately determine and control the aim of the light redirecting element.

Abstract: The present invention relates to apparatus and methods to provide a control system for the purpose of redirecting light from a source onto a target. The present invention appreciates that the diffraction pattern for light that is both diffracted and re-directed by a heliostat is a function of how the light redirecting element is aimed. This means that the aim of the light redirecting element can be precisely determined once the aim of the diffracted light is known. Advantageously, the characteristics of diffracted light indicative of how the diffracted light is aimed can be determined from locations outside the zone of concentrated illumination in which sensors are at undue risk. This, in turn, means that diffracted light characteristics can be detected at a safe location, and this information can then be used to help precisely aim the light redirecting element onto the desired target, such as a receiver in a CSP system.