Optical transmission module and optical transceiver

An optical transceiver, comprising:

• an optical transmission module configured to input differential signals comprising a positive-phase signal and a negative-phase signal;
• an optical reception module;
• and
• a driver configured to output the differential signals,
• the optical transmission module comprising:
• a laser oscillator configured to output laser light;
• an optical modulator configured to modulate the laser light based on the positive-phase signal;
• a negative-phase terminating resistor configured to terminate the negative-phase signal;
• a Peltier device comprising a first region and a second region in which heat is exchanged;
• a substrate mounted to the first region so that heat is conducted to the first region;
• and
• a package which is hermetically sealed and in which at least the laser oscillator, the optical modulator, the negative-phase terminating resistor, the Peltier device, and the substrate are arranged,
• the laser oscillator and the optical modulator being mounted on the substrate so that heat is conducted to the first region,
• the negative-phase terminating resistor being arranged outside of the substrate so as to avoid conduction of heat to the first region,
• the driver being arranged outside of the package.