On May 4, 1852, U.S. Patent No. 341,214 issued to C. Bell and Charles Sumner Tainter on Recording and Reproducing Speech and Other Sounds (the disc-shaped record).
On May 3, 1966, U.S. Patent No. 3,249,473 issued to Nick Holonyak, Jr., on the Use of Metallic Halide as a carrier Ga in the Vapor Deposition of III-V Compounds (making LED’s in the visible light spectrum).