US 12,282,188 B2
Ring-resonator filter device
Junichi Hasegawa, Tokyo (JP); and Noritaka Matsubara, Tokyo (JP)
Assigned to FURUKAWA ELECTRIC CO., LTD., Tokyo (JP)
Filed by FURUKAWA ELECTRIC CO., LTD., Tokyo (JP)
Filed on Aug. 11, 2021, as Appl. No. 17/444,871.
Application 17/444,871 is a continuation of application No. PCT/JP2020/004432, filed on Feb. 5, 2020.
Claims priority of application No. 2019-024921 (JP), filed on Feb. 14, 2019.
Prior Publication US 2021/0376570 A1, Dec. 2, 2021
Int. Cl. G02B 6/122 (2006.01); G02B 6/125 (2006.01)
CPC G02B 6/1223 (2013.01) [G02B 6/125 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A ring-resonator filter device comprising:
a waveguide device that includes a core, wherein
the core constitutes two ring resonator filters,
each of the two ring resonator filters includes two arm portions, a ring-shaped portion, and two optical coupling/branching portions that optically couple the two arm portions and the ring-shaped portion, respectively, and
the two ring-shaped portions cross each other, each of the two ring-shaped portions being formed in an 8-shape.