US 11,674,905 B2
Fluorescence imaging of gemstone on transparent stage
Tsung-Han Tsai, Little Ferry, NJ (US); and Wuyi Wang, Edison, NJ (US)
Assigned to Gemological Institute of America, Inc. (GIA), Carlsbad, CA (US)
Filed by Gemological Institute of America, Inc. (GIA), Carlsbad, CA (US)
Filed on Apr. 28, 2022, as Appl. No. 17/731,752.
Application 17/731,752 is a continuation of application No. 17/105,065, filed on Nov. 25, 2020, granted, now 11,346,788.
Claims priority of provisional application 62/940,871, filed on Nov. 26, 2019.
Prior Publication US 2022/0252520 A1, Aug. 11, 2022
Int. Cl. G01N 21/87 (2006.01); G01N 21/64 (2006.01)
CPC G01N 21/87 (2013.01) [G01N 21/6456 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of analyzing gemstones, the method comprising:
supporting a gemstone on a flat stage, wherein the stage is capable of transmitting UV to visible light, and wherein the gemstone is backed by an absorption material;
causing a light beam to emit from a light source, the light beam within a first range of wavelengths, aimed at a first dichroic beam splitter toward the flat stage,
wherein the first dichroic beam splitter is configured to reflect light of the first range of wavelengths and pass light of a second range of wavelengths; and
capturing a fluorescence image of the gemstone on the flat stage by a digital camera aimed at a second dichroic beam splitter configured to reflect light of the second range of wavelengths that pass through the first dichroic beam splitter.