ALEXANDRIA, Va., June 17 -- United States Patent no. 12,313,469, issued on May 27, was assigned to SEIKO EPSON Corp. (Tokyo).
"Laser interferometer" was invented by Kohei Yamada (Shiojiri, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A laser interferometer includes a light source configured to emit first laser light, an optical modulator including a vibrator and configured to modulate, by the vibrator, the first laser light into second laser light having a different frequency, an optical path switching unit disposed in a first optical path through which the first laser light travels and configured to switch a direction of travel of the first laser light between the first optical path and a second opt...