This paper describes the construction of an optically pumped laser device. The device utilizes a line‐tunable CO2TEA laser as a source to optically pump a cell which is capable of cooling candidate laser gases down to ∼150 °K. Laser outputs of 750 mJ in the 13‐&mgr;m region and 100 mJ in the 16‐&mgr;m region are obtained by pumping NH3and CF4respectively with 10 J of CO2laser radiation. The measured conversion efficiencies are 15% for NH3and 3% for CF4. These lasers can be used to photodissociate polyatomic molecules and are attractive sources for practical laser isotope separation.