US 11,984,699 B2
Optical semiconductor device and control method of the same
Hiromitsu Kawamura, Yokohama (JP)
Assigned to Sumitomo Electric Device Innovations, Inc., Yokohama (JP)
Appl. No. 17/049,512
Filed by SUMITOMO ELECTRIC DEVICE INNOVATIONS, INC., Yokohama (JP)
PCT Filed Apr. 23, 2019, PCT No. PCT/JP2019/017263
§ 371(c)(1), (2) Date Oct. 21, 2020,
PCT Pub. No. WO2019/208575, PCT Pub. Date Oct. 31, 2019.
Claims priority of application No. 2018-085695 (JP), filed on Apr. 26, 2018; and application No. 2019-005113 (JP), filed on Jan. 16, 2019.
Prior Publication US 2021/0242658 A1, Aug. 5, 2021
Int. Cl. H01S 5/0239 (2021.01); H01S 5/00 (2006.01); H01S 5/14 (2006.01); H01S 5/0683 (2006.01)
CPC H01S 5/0239 (2021.01) [H01S 5/0071 (2013.01); H01S 5/141 (2013.01); H01S 5/0683 (2013.01)] 4 Claims
OG exemplary drawing
 
1. An optical semiconductor device comprising:
a wavelength tunable laser element;
a beam splitter that splits an outgoing beam of the wavelength tunable laser element into a first light beam and a second light beam, and outputs the first light beam and the second light beam;
a polarizer that makes a polarization state of one of the first light beam and the second light beam different from a polarization state of the other of the first light beam and the second light beam by changing a polarization state of at least one of the first light beam and the second light beam; and
an etalon that transmits the first light beam and the second light beam that have passed through the polarizer, wherein
the etalon is composed of a material that has a refractive index unique to a polarization state of a light beam entering the etalon.