US 12,248,205 B2
Optical modulation element and method for driving optical modulation element
Hajime Utsunomiya, Tokyo (JP); and Takashi Kikukawa, Tokyo (JP)
Assigned to TDK CORPORATION, Tokyo (JP)
Appl. No. 17/924,517
Filed by TDK CORPORATION, Tokyo (JP)
PCT Filed Jul. 13, 2021, PCT No. PCT/JP2021/026216
§ 371(c)(1), (2) Date Nov. 10, 2022,
PCT Pub. No. WO2022/034767, PCT Pub. Date Feb. 17, 2022.
Claims priority of application No. 2020-135862 (JP), filed on Aug. 11, 2020.
Prior Publication US 2023/0176403 A1, Jun. 8, 2023
Int. Cl. G02F 1/035 (2006.01); G02F 1/21 (2006.01); G02F 1/225 (2006.01)
CPC G02F 1/035 (2013.01) [G02F 1/212 (2021.01); G02F 1/225 (2013.01); G02F 2202/20 (2013.01); G02F 2203/50 (2013.01)] 3 Claims
OG exemplary drawing
 
1. An optical modulation element comprising:
a first optical waveguide;
a second optical waveguide;
a first electrode configured to apply an electric field to the first optical waveguide; and
a second electrode configured to apply an electric field to the second optical waveguide,
wherein each of the first optical waveguide and the second optical waveguide includes a ridge-shaped portion protruding from a first surface of a lithium niobate film,
wherein a first interaction length L1 that is a length of a part of the first electrode overlapping the first optical waveguide in a longitudinal direction is 0.9 mm or more and 20 mm or less,
wherein a second interaction length L2 that is a length of a part of the second electrode overlapping the second optical waveguide in the longitudinal direction is 0.9 mm or more and 20 mm or less, and
wherein an applied voltage width Vpp that is an amplitude of an applied voltage applied to a part between the first electrode and the second electrode is 2.0 V or more and 4.3 V or less, and a half-wavelength voltage Vπ is equal to or higher than the applied voltage width Vpp.