Venetian blinds, pull-down screens, light-blocking films, and other sunlight screenig devices used with windows not only reduce the amount of sunlight that enters a room and lower the luminance of outside, but can also obstruct the view of outside scenery. ln this research we have therefore quantitatively expressed the luminance-reducing properties and transparency of screening devices that are superimposed on outside scenery. First, methods for quantifying the screening properties of screening devices were examined, after which we used these screening properties to predict changes in the luminance distribution of outside, which enable us to enhance screening device transparency. We then created a method for deciding on the desired characteristics for a screening device with the right combination of transparency and luminance-reducing properties for a given window.
