US 11,835,761 B2
Planar optical waveguide circuit
Osamu Moriwaki, Musashino (JP); Kenya Suzuki, Musashino (JP); Takashi Go, Musashino (JP); Manabu Oguma, Musashino (JP); and Yuichiro Ikuma, Musashino (JP)
Assigned to NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
Appl. No. 17/420,371
Filed by Nippon Telegraph and Telephone Corporation, Tokyo (JP)
PCT Filed Jan. 8, 2020, PCT No. PCT/JP2020/000243
§ 371(c)(1), (2) Date Jul. 1, 2021,
PCT Pub. No. WO2020/145284, PCT Pub. Date Jul. 16, 2020.
Claims priority of application No. 2019-003792 (JP), filed on Jan. 11, 2019.
Prior Publication US 2022/0091329 A1, Mar. 24, 2022
Int. Cl. G02B 6/12 (2006.01); G02B 6/122 (2006.01)
CPC G02B 6/122 (2013.01) [G02B 6/12007 (2013.01); G02B 2006/12104 (2013.01); G02B 2006/12164 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A planar optical waveguide circuit having an optical waveguide embedded in a cladding layer, the planar optical waveguide circuit comprising:
a plurality of parallel output optical waveguides configured to emit light from a same end face; and
a groove formed in the cladding layer, the groove having a reflective interface configured to reflect leaked light propagating in the cladding layer,
wherein:
the reflective interface includes a reflective interface formed at an angle of +45 degrees and a reflective interface formed at an angle of −45 degrees relative to the output optical waveguides,
the reflective interface formed at an angle of +45 degrees, the output optical waveguide, and the reflective interface formed at −45 degrees being arranged repeatedly in that order.