Abstract: A covering device is disclosed for substantially blocking solar rays and heat coming inwardly through an architectural opening while allowing substantial visibility outwardly through the covering and opening. The covering includes a plurality of sun blocking cells having inner perimeter walls with a depth which is effective for blocking the sun rays entering at various vertical and horizontal angles. In particular, the sides of the perimeter wall are effective for blocking sun entering at side or horizontal angles. Preferably the cells are made from thin strip material so that the covering has a total open area greater than 80% or more from a front view looking outward. Open areas as high as 95% may be achieved with the invention, while blocking substantial amounts of solar rays and heat.