Reflectance spectroscopy measuring and sampling system and method for gemstone testing

摘要

A reflectance spectroscopy measuring and sampling system for gemstone testing is disclosed. The system includes a first light source (1), a second light source (2), a light filtering element, an integrating sphere (S), an optical fiber (9), a spectroscopic detection module (10), an analog-digital conversion module (11) and a data processing terminal (12), wherein the integrating sphere (S) is provided with an entrance port, a sampling opening (6) and a reflected light exit port (7). A reflectance spectroscopy measuring and sampling method for gemstone testing is also disclosed. The system and the method have an excellent performance and can be widely used in the gemstone identification.

主权项

1. A reflectance spectroscopy measuring and sampling system for a gemstone sample, comprising:
a deuterium lamp adapted to provide an ultraviolet light having a wavelength less than 400 nm, and a halogen lamp adapted to provide a visible-to-near-infrared light having a wavelength in a range of 350 nm-2200 nm; an integrating sphere having a side, a top, and a bottom, and interior and outer peripheries, an entrance port disposed on the side, a sampling opening disposed on the top, and a reflected light exit port disposed on the outer periphery on the bottom, a first collecting mirror disposed on the reflected light exit port and/or an optically clear quartz plate disposed on the sampling opening; a dichroscope adapted to selectively filter the light emitted from the deuterium lamp that has a light wavelength greater than 400 nm and the light emitted from the halogen lamp that has a light wavelength less than 400 nm to create an ultraviolet-visible-near-infrared continuous polychromatic light; an optical lens adapted to focus the polychromatic light, wherein the polychromatic light passes through the entrance port into the interior and contacts the gemstone sample though the sampling opening after the polychromatic light undergoes multiple diffuse reflections in the integrating sphere, and the polychromatic light is then reflected by the gemstone sample after contact to form a reflected light; an optical fiber operably coupled to the reflected light exit port and adapted to receive and convey the reflected light into a spectroscopic detection module that is adapted to split the reflected light and convert photonic information contained in the reflected light into analog signals according to an order of wavelengths of the reflected light, wherein the spectroscopic detection module includes an entrance slit, a collimating mirror adapted to collimate light, a grating adapted to split light, a second collecting mirror, and a CCD sensitive array, wherein the reflected light is incident and collimated on the collimating mirror through the entrance slit and is then transferred to the grating and is split, and then is transferred to the second collecting mirror to be focused on the CCD sensitive array; an analog-digital conversion module operably coupled to the spectroscopic detection module and adapted to respectively convert the analog signals into digital signals; and a data processing terminal adapted to receive the digital signals and form a real-time spectrogram based on the digital signals.