Abstract: A window shading control system (100) includes a sensor (110) configured to produce a global radiation measurement for each direction of at least four directions, wherein each global radiation measurement is a combined direct and diffuse component of at least one of illuminance and irradiance; a processor (120) connected to the sensor and configured to compute a discrete direct component and a diffuse component for global radiation measurement; and a control circuit (130) connected to the processor and configured to control a window shading system (150) based on the discrete direct component and the diffuse component computed for at least one global radiation measurement.

Abstract: The present invention provides for a device for blocking direct light from a light source, wherein the device comprises two arrays of elongated slats and a means to coordinately move the two arrays relative to each other within a range of configuration, wherein in at least one configuration the two arrays block direct light from a light source to more than one location incident to the light source while not blocking other views through the two arrays from the more than one location.