Thermoelectric Cooling – Peltier
A Thermoelectric Cooler (TEC) also known as Peltier Cooler is an electrically driven, solid-state heat pump using the Peltier effect: Heat is absorbed or generated at the contact points in addition to Joule heating if an electric current flows through a circuit of two dissimiliar conductors. The direction of the electric current define which contact is heated or cooled. The cooling rate depends on the the electrical current while the direction of the pumped heat can be reversed simply by switching the directon of the electric current.
TECs are widely used for the temperature control of Optoelectronic components like Lasers and LEDs. Telecom Laser, Pump laser, Diode Pumped Solid-State (DPSS) Lasers and Vertical Cavity Surface Emitting Laser (VCSEL) need a very precise thermal management by TECs to stabilize the emitted wavelength. The self-heating of powerful LEDs makes the use of TECs necessary to prolong its lifetime.
The scalibility and miniaturization makes TECs usable for TO-type packaging together with photonics. Photodetectors and Detector Arrays of all different kinds make use of TECs because of their unique advantages like reliability, long operation life time and no vibrations.
The simple and fast change between heating and cooling operation by switching the direction of the current favors TEC for cycling applications. As an example, TECs are used in medical equipment for polymerase chain reaction (PCR) to carry out DNA analysis with the help of rapid periodic heating and cooling of biological probes
TECs are also used in automotive applications for heating and cooling applications like cup holders, seats and thermal pads, which experience bodily contact, for drivers comfort and safety aspects.
TECs are ideal for calibration of blackbodies for low and medium temperature ranges from -40 °C to +150 °C due to the lateral temperature homogeinity across the device.