IN-POWDER FOREIGN MATTER DETECTION DEVICE AND FOREIGN MATTER DETECTION METHOD USING TERAHERTZ PULSE WAVE

摘要

PROBLEM TO BE SOLVED: To provide an in-powder foreign matter detection device and foreign matter detection method, using terahertz pulse wave, that can accurately detect foreign matter in powder.SOLUTION: A foreign matter detection device comprises: an oscillation part 11 which generates and emits a terahertz wave as irradiation light; an optical system 12 which guides the irradiation light to powder and converges reflected light and/or transmitted light from the powder; a reception part 13 which outputs a signal corresponding to the converged reflected light and/or the transmitted light; a scanning mechanism 14 which scans the position on the powder to which the irradiation light is guided; and an arithmetic part 15 which detects foreign matter 21 in the powder based upon at least one of a time waveform signal output in time series from the reception part, a reflected image, a power spectrum, and a frequency image.SELECTED DRAWING: Figure 2