The utility model relates to the field of near-
infrared analytical instruments, and discloses a
paraboloid-shaped sample disc and a
spectrograph for near-
infrared diffuse reflection spectrum acquisition, the
paraboloid-shaped sample disc comprises a sample box for storing samples, the sample box is provided with a first side and a second side which are opposite, the first side of the sample box is transparent, the second side of the sample box is provided with a
paraboloid-shaped reflector, and the paraboloid-shaped reflector is arranged on the first side of the sample box; the paraboloid of the paraboloid type reflecting mirror faces the first side of the sample box, and the
spectrograph corresponds to the sample box. According to the device,
scattered light and transmission light which are not received by the
optical fiber originally are utilized through the paraboloid type reflecting mirror and the
quartz glass, the
absorbance value of a
solid sample is increased, the
scattering effect is reduced, and the
background noise intensity is reduced;
wavelength calibration is achieved through the PET sheet and the
ceramic white board, and errors caused by
light source intensity fluctuation and
wavelength drift in the detection process are reduced. Finally, the
baseline drift phenomenon and the
stray light problem in an
optical path system are reduced, the sampling representativeness is improved, the result
repeatability and the
signal-to-
noise ratio are improved, and the spectrum collection accuracy is remarkably improved.