the heat will accumulate in the
LED case until it is brought away by the TEC. At the same time,
an aluminum plate between the TEC cold side and the LED module
will lead to the ‘‘delayed cooling effect’’ of TEC. Hence, when the
power is on, the case temperature will rise first. After that, the
accumulated heat started to be transferred from the case to the liquid
cold plate or heat sink by the TEC. It can also be seen from Fig. 7