Semiconductor laser module

A semiconductor laser module, comprising a semiconductor laser;

• a driving circuit for driving said semiconductor laser;
• a heating element for controlling temperature of said semiconductor laser;
• a temperature sensor for sensing temperature near or around said semiconductor laser and said heating element;
• and a temperature control unit for controlling said heating element on the basis of temperature information from said temperature sensor, wherein
• said temperature control unit controls said heating element without the use of Peltier cooling means so as to keep said semiconductor laser at the same temperature as ambient air temperature or higher than it.

A semiconductor laser module, comprising:

• a semiconductor laser;
• a driving circuit for driving said semiconductor laser;
• a heating element for controlling the temperature of said semiconductor laser without involving a Peltier cooling operation;
• a temperature sensor for sensing temperature near or around said semiconductor laser and said heating element;
• and a temperature control unit for controlling said heating element on the basis of temperature information from said temperature sensor, wherein
• said temperature control unit controls said heating element so as to keep said semiconductor laser at the same temperature as ambient air temperature or higher than it.

A semiconductor laser module, comprising:

• a semiconductor laser;
• a driving circuit for driving said semiconductor laser;
• a heating element for controlling temperature of said semiconductor laser;
• a temperature sensor for sensing temperature near or around said semiconductor laser and said heating element;
• a temperature control unit for controlling said heating element on the basis of temperature information from said temperature sensor;
• and a supporting substrate, wherein
• at least said semiconductor laser, said heating element and said temperature sensor are mounted on a main surface of said supporting substrate, wherein
• a main surface of a semiconductor chip of said semiconductor laser, on which joining for emitting laser light has been formed, is disposed on said main surface of said supporting substrate, wherein
• said heating element is disposed in proximity to said joining on said main surface of said semiconductor chip of said semiconductor laser on said main surface of said supporting substrate, and wherein
• said temperature control unit controls said heating element so as to keep said semiconductor laser at the same temperature as ambient air temperature or higher than it.

An optical transceiver comprising an optical receiving module and an optical transmitting module, wherein said optical transmitting module comprises:

• a semiconductor laser;
• a driving circuit for driving said semiconductor laser;
• a heating element for controlling temperature of said semiconductor laser without involving any Peltier cooling operation;
• a temperature sensor for sensing temperature near or around said semiconductor laser and said heating element;
• and a temperature control unit for controlling said heating element on the basis of temperature information from said temperature sensor, wherein said temperature control unit controls said heating element so as to keep said semiconductor laser at the same temperature as ambient air temperature or higher than it, and wherein
• said optical transmitting module and said optical receiving module are housed within one housing.

An optical receiver, comprising:

• a semiconductor photo detector for receiving an optical information signal from a recording medium or a communication system;
• a signal processing unit for processing an electric signal from said semiconductor photo detector;
• a heating element for controlling temperature of said semiconductor photo detector;
• a temperature sensor for sensing temperature near or around said semiconductor photo detector and said heating element;
• a temperature control unit for controlling said heating element on the basis of the temperature information from said temperature sensor, wherein
• said temperature control unit controls said heating element without the use of the Peltier cooling means so as to keep said semiconductor photo detector at the same temperature as ambient air temperature or higher than it.