US 12,259,279 B1
Electromagnetic wave measuring apparatus and electromagnetic wave measuring method
Kota Nishimura, Gifu (JP); Takeshi Sugiyama, Gifu (JP); and Shintaro Hisatake, Gifu (JP)
Assigned to Photonic Edge Inc., Gifu (JP)
Filed by Photonic Edge Inc., Gifu (JP)
Filed on Jan. 9, 2024, as Appl. No. 18/407,941.
Claims priority of application No. 2023-183951 (JP), filed on Oct. 26, 2023.
Int. Cl. G01J 9/00 (2006.01)
CPC G01J 9/00 (2013.01) 9 Claims
OG exemplary drawing
 
1. An electromagnetic wave measuring apparatus, comprising:
a light source unit configured to output a first laser beam whose frequency is settable in a predetermined frequency range, and a second laser beam;
an electro-optic probe configured to receive the first laser beam of a frequency that has been set in the frequency range, the second laser beam, and a detection-target electromagnetic wave;
an optical filter configured to receive a light beam output from the electro-optic probe and attenuate a frequency component outside a predetermined passband; and
a light-receiving element configured to convert a light beam that has passed through the optical filter into an electrical signal,
wherein the electro-optic probe outputs, to the optical filter, the first laser beam, the second laser beam, a first sideband beam generated by modulating the first laser beam, and a second sideband beam generated by modulating the second laser beam,
wherein the optical filter attenuates the frequency component outside the passband, which is at least one of a frequency component of the first laser beam and a frequency component of the second sideband beam, or at least one of a frequency component of the second laser beam and a frequency component of the first sideband beam, and
wherein the light source unit includes:
a variable-wavelength first laser configured to output the first laser beam,
a second laser configured to output the second laser beam, and
a control unit configured to control the frequency of the first laser beam to be output by the first laser.