US 12,306,479 B2
Optical modulator and optical transmission apparatus using same
Norikazu Miyazaki, Tokyo (JP); and Toru Sugamata, Tokyo (JP)
Assigned to SUMITOMO OSAKA CEMENT CO., LTD., Tokyo (JP)
Appl. No. 17/763,959
Filed by SUMITOMO OSAKA CEMENT CO., LTD., Tokyo (JP)
PCT Filed Sep. 15, 2020, PCT No. PCT/JP2020/034975
§ 371(c)(1), (2) Date Mar. 25, 2022,
PCT Pub. No. WO2021/060088, PCT Pub. Date Apr. 1, 2021.
Claims priority of application No. 2019-175517 (JP), filed on Sep. 26, 2019.
Prior Publication US 2022/0334415 A1, Oct. 20, 2022
Int. Cl. G02F 1/01 (2006.01); G02F 1/03 (2006.01)
CPC G02F 1/0126 (2013.01) [G02F 1/0316 (2013.01)] 9 Claims
OG exemplary drawing
 
1. An optical modulator comprising:
an optical modulation element that is configured to generate two modulated light beams, each of which is modulated by two sets of electrical signals, each set including two electrical signals, and that includes a plurality of signal electrodes;
a plurality of signal input terminals, each of which inputs an electrical signal to be applied to each of the signal electrodes;
a relay substrate on which a plurality of signal conductor patterns that electrically connect the signal input terminals to the signal electrodes and a plurality of ground conductor patterns are formed, the relay substrate being configured to propagate the two sets of electrical signals by two pairs of the signal conductor patterns, each pair being composed of two adjacent signal conductor patterns; and
a housing in which the optical modulation element and the relay substrate are accommodated,
wherein each of at least one pair of two adjacent signal conductor patterns includes a component mounting portion including at least a parallel circuit of a resistor and a capacitor, each of the component mounting portions is mounted on portions of the two adjacent signal conductor patterns having different signal propagation directions to each other, and
the relay substrate includes a metal body connected on the ground conductor pattern or a substrate removal portion from which a substrate material of the relay substrate is removed, the metal body or the substrate removal portion being provided at a position sandwiching a portion of each of the at least one pair of two signal conductor patterns downstream of the component mounting portion along a propagation direction of the electrical signal.