Patent ID: 8872870

Claim:
A method for marking of glass or a glass-like material for forming an array of marks in or on the glass or glass-like material, the array consisting of a plurality of discrete marks formed in discrete marking steps and distributed along at least one predetermined direction, comprising a plurality of discrete marking steps, in which, in each marking step a writing laser beam and the glass or glass-like material are moved relative to each other, wherein for any given pair of marks, which are directly adjacent to each other in any one of said at least one predetermined direction, the pair of marks are formed in two separate marking steps that are not carried out directly in succession one after the other; and the plurality of discrete marking steps form at least two series of marks in said at least one predetermined direction, which are spaced apart from each other in regular intervals and interleaved in the predetermined direction; in which method the respective series of regularly spaced marks is formed either by a row-wise or column-wise relative movement between the writing laser beam and the glass or glass-like material along the predetermined direction or by the formation of the marks in a random sequence, the array of marks or the array of marks together with its immediate vicinity is heated to a predetermined temperature above the transformation temperature Tg of the glass, and the marks or the array of marks are cooled in a controlled manner during and/or after performing the marking steps until attaining a second predetermined temperature below the transformation temperature Tg of the glass.