used to distribute natural light evenly across the cycloid curve of the ceiling. He hired a computer expert to determine the exact shape of the reflector's curve, making it one of the first architectural elements to be designed with computer technology. In areas without art, such as the lobby, cafeteria and library, the entire reflector is perforated, making it possible for people standing beneath to glimpse passing clouds. In the gallery spaces, the central part of the reflector, which is directly beneath the sun, is solid, while the remainder is perforated. The concrete surfaces of the ceiling were given a high finish to further assist the reflection of the light. The result is that the strong Texas sun enters a narrow slot at the top of each vault and is evenly reflected from a curved screen across the entire arc of the polished concrete ceiling, ensuring a beautiful distribution of natural light that had never before been achieved. Expansion In 1989, director Ted Pillsbury, Brown's successor, announced plans to add two wings to the north and south ends of the building and chose architect Romaldo Giurgola to design them. A firestorm of protest erupted. Critics pointed out that founding director Brown's "Pre-Architectural Program" had specified that "the form of the building should be so complete in its beauty that additions would spoil that form," and that Kahn had achieved that goal extraordinarily well. A group of prominent architects signed a letter acknowledging the need for additional space but arguing that the proposed addition would compromise the proportions of the original. They noted that when Kahn himself was questioned about the possibility of a future expansion, he said that it should "occur as a new building and be situated away from the present structure across the lawn". Esther Kahn, Louis Kahn's widow, published a letter voicing similar sentiments, noting that "there is room on the site for a separate building, which could be connected to the present museum." The project was cancelled a few months later. Renzo Piano Pavilion In 2006, the idea of an expansion surfaced once again at a dinner in Fort Worth attended by Timothy Potts, the museum's director at the time (Eric M. Lee has been the director since March 2009); Kay Fortson, president of the Kimbell Art Foundation and a key figure in the creation of the original building; Ben Fortson, a trustee; and Sue Ann