Optical modulator and optical module

An optical modulator comprising:

• an optical modulator chip configured to optically modulate an optical signal using an electrical signal input thereto;
• and
• a relay substrate configured to relay and couple the electrical signal to the optical modulator chip, wherein
• the optical modulator chip includes a signal electrode and a ground electrode for the electrical signal, formed along a waveguide for the optical signal,
• one end of the optical modulator chip is arranged to face the relay substrate, and an electrode connection portion configured to couple the electrical signal to the relay substrate using a wire is provided at the one end,
• the ground electrode positioned in the electrode connection portion has:
• a first tip that is adjacent to the signal electrode;
• and
• a broad portion having a distance to the one end of the optical modulator chip becoming larger as the broad portion becomes more distant from the signal electrode, and
• a distance between a tip of one end of the signal electrode positioned in the electrode connection portion and the one end of the optical modulator chip, and a distance between the first tip of one end of the ground electrode and the one end of the optical modulator chip are both less than a distance between the broad portion of the ground electrode and the one end of the optical modulator chip.