Numerical analysis on the cooling of a laser diode package with a thermoelectric cooler

An LD (laser diode), an essential unit of an LD package, has higher output power and faster working speed than an LED (light‐emitting diode) but it is more expensive. The thermal characteristic of an LD should be estimated as the working performance as it is closely related to its temperature. The thermal expansion causes changes in its shape and position, which lead to a crucial problem regarding light transmission. An LD is located on the submount for insulation and cooling and all of them work in a closed package filled with an inert gas. A TEC (thermoelectric cooler) is used in order to control the temperature of the package, especially the LD.