The solution to a problem in asymmetric reflector design for illumination is described. Working backward from a required rectangular and nonuniform light distribution pattern, the reflector geometry is arrived at by a combination of calculus and geometric construction. The central curve is computed from the general reflector equation lnR = tan (θ - d/2) dθ, the integration being performed on an approximate matching function or graphically. The off-center contours are then obtained by means of an original drafting-board construction which is described, and the complete reflector shape is thus defined.
William B. Elmer, "A Study in Street Lighting Reflector Design," Appl. Opt. 5, 343-343 (1966)