Aspheric lenses used in the thermal imaging are typically fabricated using expensive single-crystal materials (Ge and ZnS, etc.) by the costly single point diamond turning (SPDT) process. As a potential solution to reduce cost, compression molding method using chalcogenide glass has been attracted to fabricate IR optic. Thermal deformation of a molded lens should be compensated to fabricate chalcogenide aspheric lens with form accuracy of the submicron-order. The thermal deformation phenomenon of molded lens was analyzed ant then compensation using mold iteration process is followed to fabricate the high accuracy optic. Consequently, it is obvious that compensation of thermal deformation is critical and useful enough to be adopted to fabricate the lens by molding method.

With the recent development of less-costly uncooled detector technology, expensive optics are among the remaining significant cost drivers in the thermography camera. As a potential solution to this problem, the fabrication of IR lenses using chalcogenide glass has been studied in recent years. We report on the molding and evaluation of a ultra-precision chalcogenide-glass lens for the thermography camera for body-temperature monitoring. In addition, we fabricated prototype thermography camera using the chalcogenide-glass lens and obtained the thermal image from the camera. In this work, it was found out that thermography camera discerned body-temperature between 20 and 50℃ through the analysis of thermal image. It is confirmed that thermography camera using the chalcogenide-glass lens is applicable to the body-temperature monitoring system.

In this study, we synthesized the chalcogenide glass(Ge19Sb23Se58) for infrared optics by melt-quenching method and verified the effect of cooling condition on the glass properties. The structural and optical properties of the glass were analyzed by XRD, FT-IR and SEM image. The glass synthesized under the cooling temperature of 980℃ shows transmittance of 58% at 8∼12 ㎛, which was decreased as the cooling temperature was decreased. In addition, thermal and hardness also were measured. From the analysis results, we ascertained the feasibility as a molding materials for infrared optics.