Summer sun can be a restaurant's most unwanted guest.
Indoors, its heat strains air-conditioning systems to their limits. Outdoors, it can turn al fresco dining into an exercise in heat endurance. For operations where sunshine ranks among the toughest challenges, there are ways to battle it without entirely blocking its brighter aspects. Inside, a family of special films designed to shield heat and ultraviolet rays can be applied to window interiors. The films, applied to glass like invisible wallpaper, help even out imbalances between sunny and shady, hot and cool areas of a room.