Multilevel thermoelectric cooling stack with thermal guard rings

A multilevel thermoelectric cooling (TEC) apparatus comprising:

• a first thermoelectric cooling (TEC) level comprising a first TEC device and a first guard ring, the first guard ring configured for extending from the first TEC device at a periphery of the first TEC device, the first TEC device configured for receiving an element within the periphery to be cooled;
• a second TEC cooling level in thermal communication with the first TEC cooling level, the second TEC cooling level comprising a second TEC device in a stacked arrangement with the first TEC device, the second TEC device including a periphery extending beyond the periphery of the first TEC device of the first TEC cooling level and a second guard ring configured for extending from the second TEC device of the second TEC cooling level in the direction in which the guard ring of the first TEC cooling level extends, wherein the first guard ring and the second guard ring extend substantially parallel to each other to a plane;
• each of said first and second guard rings forming an isothermal boundary for the respective first and second TEC device;
• a power supply in electrical communication with the first and the second TEC devices of the respective first TEC cooling level and the second TEC cooling level, to provide power to each said TEC device and cause heat to flow from the element through each of the first and second guard rings to be channeled along the plane from the first TEC cooling level to the second TEC cooling level;
• and
• a controller in communication with the power supply and configured to adjust the temperature distribution between the stack of the first TEC cooling level and the second TEC cooling level, for minimizing the total electrical power consumed by the stack of the first TEC cooling level and the second TEC cooling level, by keeping the element at or below a threshold temperature.