SPECIMEN INSPECTING APPARATUS, AND SPECIMEN INSPECTING METHOD

A sample inspection apparatus includes an oscillator 14-2 which generates light rays of terahertz radiation, an optical system 14-3 which guides the terahertz radiation to a drug, a detection unit 16-4 which detects the terahertz radiation transmitted through an object as an electrical signal, and a computer 20 which determines by analysis whether the sample contains heterogeneous or foreign substances or not based on the temporal waveform of the electrical signal detected by the detection unit 16-4 and the predetermined temporal waveform indicating the component unique to the sample, or determines the spectrum from the electrical signal detected by the detection unit 16-4, extracts plural feature values from the spectrum and determines whether the drug contains heterogeneous or foreign substances or not based on the extracted feature values and the feature values extracted from the predetermined spectrum (fingerprint spectrum) due to the component unique to the drug.