attachable spectroscope to an auxiliary CCD or CMOS camera as detector for gem identification

An attachable spectroscope to an auxiliary CCD or CMOS camera as detector for gem identification, wherein the spectroscope comprising:

• a tube, an incident window, a slit, lens, a newly designed grism, and an exit window;
• the fixing device is designed to be a clamp or shell which incorporates screw to fix the spectroscope on the exit window side, and an avoid hole in the inside the screw. The incident window is located on one side of the tube with the slit near it. The exit window is on the other side of the tube;
• the diffracting grism locates close to the exit window in the tube.
• The fixing device is designed to attach the spectroscope to the auxiliary camera as detector, it incorporates a screw to fix the spectroscope on the exit window side, and an avoid hole in the inside the screw. The avoid hole is transparent and aligned to the camera, thus, the light ray of the gem under test goes through the incident window, the slit, the lens, the newly designed grism and the exit window, then the light beam goes into the camera and collected by the CCD or CMOS image sensor, the light spectrum can be transferred into digital data.