ALBANY, Ga. - For a quarter century, chefs at pricey steakhouses have been searing meat on burners that cook with infrared energy. Now the high-temperature technology may be coming to a backyard barbecue near you. With the expiration of a key patent, major gas grill manufacturers, including market leader Char-Broil, have scrambled to bring infrared cooking to the masses with models in the $500 to $1,000 range. Previously, such grills cost as much as $5,000. "Infrared is really hot," said Leslie Wheeler, a spokeswoman for the Hearth, Patio & Barbecue Association, an industry group in Arlington, Va. "They're great for...