Issued Patents All Time
Showing 1–11 of 11 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 12292385 | Gemstone colour grading process and grading system | Wing Yan Lee, Juan CHENG, Chun Yan Dominique Lau, Wing Chi TANG, Ka Wing Cheng +1 more | 2025-05-06 |
| 12030217 | Method of marking a diamond, markings formed from such methods and diamonds marked according to such method | Yau Chuen YIU, Ka Wing Cheng | 2024-07-09 |
| 11879859 | Process for determining the type of a diamond | Ka Wing Cheng, Yau Chuen YIU, Kong CHAN, Chun Hong SHAM, Juan CHENG | 2024-01-23 |
| 11835466 | Diamond clarity measurement process and system | Ka Wing Cheng, Kin Wing Wong, Kong CHAN, Juan CHENG, Wing Chi TANG | 2023-12-05 |
| 11467101 | System for ascertaining optical characteristics of gemstone | Ka Wing Cheng | 2022-10-11 |
| 11326952 | Process and system for colour grading for diamonds | Ka Wing Cheng, Wing Chi TANG | 2022-05-10 |
| 11137355 | Process and system for diamond clarity measurement | Ka Wing Cheng, Wing Chi TANG | 2021-10-05 |
| 11016033 | Diamond clarity measurement process and system | Ka Wing Cheng, Kin Wing Wong, Kong CHAN, Juan CHENG, Wing Chi TANG | 2021-05-25 |
| 10762666 | Colour grading process and system for diamonds | Ka Wing Cheng, Kin Wing Wong, Kong CHAN, Juan CHENG, Wing Chi TANG | 2020-09-01 |
| 10475355 | Method of providing markings to precious stones including gemstones and diamonds, and markings and marked precious stones marked according to such a method | Wing Chi TANG, Ho CHING | 2019-11-12 |
| 9901895 | Method of marking material and system therefore, and material marked according to same method | Ho CHING, Ching Tom KONG | 2018-02-27 |