Nb5N6 microbolometer array for a compact THz imaging system

A 1 x 16 Nb5N6 microbolometer array for a terahertz (THz) imaging system has been demonstrated. The system consists of an objective lens and an extended hemispherical silicon lens. A finite difference time domain (FDTD) method was used to analyze the imaging system in detail. The calculated field-of-view of the system is about 7 degrees and the half-power beam width is about 160 m. The microbolometer array chip is attached to the silicon lens for 0.3 THz detection. The preliminary results for the actual system shows that the mutual coupling among these antenna integrated elements can be ignored when the spacing is larger than 500 m. The calculated results agree with the experimental data well, which means that the FDTD method can be used to evaluate and optimize such a compact THz imaging system. This linear imaging system should find direct application in active THz imaging.