Patent ID: 7532406

Claim:
A device for homogenizing light, comprising: a first cylindrical lens array through which the light to be homogenized passes, said first cylindrical lens array having convex and concave cylindrical lenses with mutually parallel cylinder axes disposed next to one another in an alternating fashion; and a second cylindrical lens array through which the light that has passed through said first cylindrical lens array can pass, said second cylindrical lens array having convex and concave cylindrical lenses with mutually parallel cylinder axes disposed next to one another in an alternating fashion, said mutually parallel cylinder axes of said cylindrical lenses of said second cylindrical lens array being aligned parallel to said mutually parallel cylinder axes of said cylindrical lenses of said first cylindrical lens array, and in a given direction in which said cylindrical lenses are disposed next to one another, said concave cylindrical lenses of said first cylindrical lens array have a configuration other than that of said concave cylindrical lenses of said second cylindrical lens array in said given direction in which said cylindrical lenses are disposed next to one another, wherein said convex cylindrical lenses of said second cylindrical lens array have a focal length approximately as large as a distance between said first cylindrical lens array and said second cylindrical lens array.