Macbeth-Evans Glass Co. v. L. E. Smith Glass Co.

I have trouble in finding invention in the lens of the patent. The thing the patentee did, when stated in simple terms, was this: In a plain lens of an automobile lamp he cut transverse horizontal refracting ridges, thus employing a well known expedient of the optical art for deflecting rays of light. For this (in conjunction with mechanism not here involved) he was granted Letters Patent No. 1,119,848, issued December 8, 1914. In this lens,some time later, he cut sections of vertical cylinders, again employing a well known expedient of the art for spreading rays laterally. Letters Patent No.…