Conventional diffraction gratings suffer from order overlap problems, especially for a mid-infrared optical emission spectrometer (mid-IR OES) using a detector array. Because of diffraction order overlap, ambiguous spectroscopic data are inevitably acquired. This shortcoming motivated us to devise an order-sorting method. We predicted a second-order diffraction overlap and corrected the deformation of signal measured with a mid-IR OES using an array detector. It is found that the first-order signal separated from the overlapped spectrum fit well with the intrinsic signal of incident light. We determined the system response function of a mid-IR OES and confirmed the validity of the compensation method by comparing the measured spectrum with Planck's curve of blackbody radiation at two different temperatures. In addition, for accuracy verification, the uncertainty factors that could affect the compensation procedures were carefully considered.
Bibliographical noteFunding Information:
This work was supported by the Low Observable Technology Research Center Program of Defense Acquisition Program Administration and Agency for Defense Development. We would like to express our deepest gratitude to C.S. Lee and Y.M. Kim for technical support in the measurement of grating incident angle.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics