US 12,278,463 B2
External resonant laser module
Atsushi Sugiyama, Hamamatsu (JP); Takahide Ochiai, Hamamatsu (JP); Tadataka Edamura, Hamamatsu (JP); and Naota Akikusa, Hamamatsu (JP)
Assigned to HAMAMATSU PHOTONICS K.K., Hamamatsu (JP)
Filed by HAMAMATSU PHOTONICS K.K., Hamamatsu (JP)
Filed on Feb. 16, 2022, as Appl. No. 17/672,768.
Claims priority of application No. 2021-027512 (JP), filed on Feb. 24, 2021.
Prior Publication US 2022/0271506 A1, Aug. 25, 2022
Int. Cl. H01S 5/14 (2006.01); H01S 5/02325 (2021.01); H01S 5/02345 (2021.01); H01S 5/34 (2006.01)
CPC H01S 5/142 (2013.01) [H01S 5/02325 (2021.01); H01S 5/02345 (2021.01); H01S 5/3401 (2013.01); H01S 5/3402 (2013.01)] 5 Claims
OG exemplary drawing
 
1. An external resonant laser module comprising:
a quantum cascade laser element;
a movable diffraction grating constituting an external resonator of the quantum cascade laser element, including:
a diffraction grating portion configured to diffract and reflect light emitted from the quantum cascade laser element; and
a coil through which a current flows to oscillate the diffraction grating portion;
a lens holder disposed between the quantum cascade laser element and the movable diffraction grating and configured to hold a lens for passing an outgoing light from the quantum cascade laser element and a light returned from the movable diffraction grating to the quantum cascade laser element;
a package configured to accommodate the quantum cascade laser element, the movable diffraction grating, and the lens holder;
an electrode terminal disposed along an inner wall surface of the package; and
a wire configured to electrically connect the electrode terminal and the coil,
wherein the package includes:
a bottom wall;
a side wall erected on the bottom wall and formed in an annular shape so as to surround a region in which the quantum cascade laser element is accommodated when viewed from a direction perpendicular to the bottom wall; and
a top wall closing an opening of the side wall on a side opposite to a side where the bottom wall is disposed,
wherein the top wall faces the bottom wall in a direction orthogonal to an optical axis direction along with an optical axis of the lens,
wherein the movable diffraction grating includes an electrode pad electrically connected to the coil,
wherein the electrode pad is connected to the electrode terminal via the wire, and
wherein a height position of the electrode pad with respect to the bottom wall is equal to or higher than a height position of the electrode terminal with respect to the bottom wall.