公开(公告)号：US12030217B2

公开(公告)日：2024-07-09

申请号：US17624332

申请日：2020-07-24

Applicant: MASTER DYNAMIC LIMITED

Inventor： Yau Chuen Yiu ,  Ka Wing Cheng ,  Koon Chung Hui

IPC: B28D5/04 ,  B42D25/324 ,  B42D25/435

CPC classification number: B28D5/04 ,  B42D25/324 ,  B42D25/435

Abstract: A process of forming a non-optically detectable authentication marking (110), includes the step of: applying a marking at a surface of a diamond (200) using a focused ion beam (FIB) writing process so as to provide a non-optically detectable authentication marking (110) which is formed by alteration in the optical characteristics of a portion of the diamond material at the outer surface of the diamond to form a marked portion; wherein the marking is optically invisible, and wherein the marking is viewable by an imaging method which provides an observable contrast between the portion of the diamond having altered optical characteristics and the non-marked portion of the diamond. The marking process can assist in the prevention of the counterfeiting of precious articles, and be of assistance in the incident of theft. A marking, a diamond, a process of viewing a marking on a diamond are further disclosed.

公开(公告)号：US20240383074A1

公开(公告)日：2024-11-21

申请号：US18417804

申请日：2024-01-19

Applicant: Master Dynamic Limited

Inventor： Yau Chuen YIU ,  Ka Wing Cheng ,  Koon Chung Hui

IPC: B23K26/359 ,  B23K26/06 ,  B23K26/0622 ,  B23K26/08 ,  B23K26/082 ,  G06V20/80

Abstract: A process of forming a non-optically detectable authentication marking (210,320, 410,535) in a diamond (200,300). Authentication marking (210,320,410,535) is formed adjacent the outer surface of an article formed from a diamond material having intrinsic optical centers. Method includes the step of applying an image of predesigned authentication marking (210,320,410,535) to a region (201,310,530) of a diamond (200,300) at or adjacent the surface of the diamond (200,300) by way of a direct laser writing; wherein the fluorescence background of the diamond material from intrinsic optical center is suppressed by authentication marking (210,320, 410, 535) under fluorescent imaging, such that the non-optically detectable identifiable authentication marking (210,320,410,535) is viewable against the fluorescence background at the region (201,310,530) of the diamond (200,300) where the authentication marking (210,320,410,535) is applied.

公开(公告)号：US10475355B2

公开(公告)日：2019-11-12

申请号：US14286306

申请日：2014-05-23

Applicant: Master Dynamic Limited

Inventor： Koon Chung Hui ,  Wing Chi Tang ,  Ho Ching

IPC: G09F3/00 ,  A44C17/00 ,  B41M5/24 ,  G02B5/18 ,  B23K26/00 ,  B23K26/352 ,  G01J1/08 ,  G09F23/00 ,  G01N21/87 ,  B23K103/00

Abstract: An identifiable mark on a portion of a polished facet of a surface of an article and being identifiable by an optical magnifying viewing device, the identifiable mark comprising a nano-structure formed by a two-dimensional or a three-dimensional lattice of a plurality of discrete nanometer sized recessed or protruded entities, wherein the entities are arranged within a predefined region of the polished facet in a predetermined arrangement in relation to each other. The predetermined arrangement of the entities is non-uniform and non-periodic arrangement, and wherein the entities are sized and shaped so as to cause optical scattering upon reflection of incident light having one or more predetermined wavelengths by the lattice at a predetermined angle of incidence to the lattice and the distance from the inner interface surface to the outer interface surface is greater than the amplitude of the non-marked portion of the polished face.