Patent ID: 8324528

Claim:
A production method of a scribing wheel with ground surface irregularities and for a substrate of a brittle material by use of a laser beam comprising steps of; a) working a bulk material of sintered diamond so as to form a radial ridge by forming two bevelled surfaces converging said radial ridge, b) irradiating a laser beam onto a portion of said radial ridge, and c) successively forming a plurality of grooves having openings in radial directions with a predetermined pitch and within a depth of 200 micrometer through a laser ablation process, wherein a first part of a groove is formed by a first irradiation from a first edge of said groove in a first direction by moving said laser beam relative to said scribing wheel, and a second part of said groove other than said first part is formed by a second irradiation from a second edge of said groove in a second direction opposite to said first direction by moving said laser beam relative to said scribing wheel, wherein a wave length of said laser beam is between 125 and 1066 nm, a pulse width of one pulse is between 5 fsec, and 50 nsec., and a repetition cycle is between 300 Hz and 5 kH.