To use a strong laser beam by providing a laser beam attenuation device on a surface that opposes a laser emission device while sandwiching a measurement target.
While sandwiching a measurement target 4, a laser beam attenuation device 7 is installed at a position that opposes a laser beam emission device 1 of a pipe 6. Laser beams 2 from the laser beam emission device 1 are focused by a lens 3 and are applied to the measurement target 4, light emitted from the measurement target 4 is analyzed by a spectroanalysis device 5, and the constituents of the measurement target 4 are estimated. The laser beams 2 that leaked toward a rear part without hitting against the measurement target 4 received by the laser beam attenuation device 7 and are attenuated. In this manner, the laser beams 2 that leaked toward the rear part are attenuated and the influence to a surrounding is eliminated, thus enabling a strong laser beam emission device 1 to be used. Also, even the measurement target 4 for causing the laser beams 2 to leak can be measured.
DEGUCHI YOSHIHIRO
SHINADA OSAMU
