Method and apparatus for controlling the temperature of a device using independent multi-stage thermoelectric coolers

Apparatus for temperature control of a device comprising:

• an internal thermoelectric cooler mounted within a device for transferring thermal energy internal to the device to an external thermoelectric cooler, said internal thermoelectric cooler having a first surface and a second surface;
• an internal thermistor mounted within the device and generating an internal thermistor output signal related to the internal temperature of the device;
• a first temperature feedback control for controlling the internal thermoelectric cooler in response the output signal of the internal thermistor;
• an external thermoelectric cooler for transferring thermal energy external to the internal thermoelectric cooler to a thermal conduit, said external thermoelectric cooler having a first surface and a second surface, said first surface of said external thermoelectric cooler mounted to said second surface of the internal thermoelectric cooler;
• an external thermistor mounted to the first surface of the external thermoelectric cooler and generating an external thermistor output signal related to the temperature of the first surface of the external thermoelectric cooler;
• and
• a second temperature feedback control for controlling the external thermoelectric cooler in response to the output signal of the external thermistor.

Apparatus for temperature control of a laser diode comprising:

• an internal thermoelectric cooler mounted within a laser diode package for transferring thermal energy internal to the laser diode package to an external thermoelectric cooler, said internal thermoelectric cooler having a first surface and a second surface;
• an internal thermistor mounted to the laser diode package and generating an output signal related to the temperature of the laser diode package;
• a first temperature feedback control for controlling the internal thermoelectric cooler in response to the output signal of the internal thermistor;
• an external thermoelectric cooler for transferring thermal energy external to the laser diode package to a thermal conduit, said external thermoelectric cooler having a first surface and a second surface, said first surface of said external thermoelectric cooler in contact with the second surface of said laser diode package;
• an external thermistor mounted to the first surface of the external thermoelectric cooler and generating an output signal related to the temperature of the first surface of the external thermoelectric cooler;
• and
• a second temperature feedback control for controlling the external thermoelectric cooler in response the output signal of the external thermistor.

A method for controlling the temperature in a device comprising the steps of:

• generating by means of a first external thermistor a first output signal related to the temperature of the device to be temperature controlled;
• activating a first external thermoelectric cooler in response to the first output signal;
• generating by means of a second external thermistor a second output signal representative of the temperature of the first thermoelectric cooler;
• activating a second external thermoelectric cooler in response to the second output signal;
• detecting an error in the operation of the first external thermoelectric cooler;
• and
• generating a first alarm signal.

A method for controlling the temperature of a device comprising the steps of:

• generating by means of an internal thermistor a first output signal related to the temperature of the device to be temperature controlled;
• activating an internal thermoelectric cooler in response to the first output signal;
• generating by means of an external thermistor a second output representing the temperature of the internal thermoelectric cooler;
• activating an external thermoelectric cooler in response to the second output signal;
• detecting an error in the operation of the external thermoelectric cooler;
• and generating a first alarm signal.