Abstract: A solid state thermoelectric refrigeration apparatus suitable for cooling various types of optical radiation detectors to desired operating temperatures, without the need for augmented cooling from any supplementary refrigeration apparatus. The refrigeration apparatus contains several thermoelectric cooling arrays of successively smaller size arranged in a generally pyramidal configuration, with a separate thermally-conductive base plate disposed between each adjacent pair of cooling arrays. The cooling arrays each include Peltier cooling elements arranged in a planar configuration. Polished, thermally-conductive, cup-shaped heat shields are attached to the successive base plates and arranged in a nested relationship, with each heat shield and associated base plate enclosing all of the successively smaller shields and base plates. Each base plate is thermally driven by the preceding thermoelectric cooling array, which also cools the associated heat shield.