Patent ID: 7642483

Claim:
A glass plate cutting machine to generate a scribe line on the glass plate and then break the plate, comprising: a cracking unit to provide a micro-crack at a cutting initiation point of a glass plate; an irradiation unit to irradiate at least one laser beam, which is absorbed in the glass plate, to the glass plate to heat the glass plate, and including a first carbon dioxide laser beam irradiation part; a cooling unit to cool the glass plate by use of a cooling fluid after irradiation of the at least one laser beam, and including a first cooling part disposed at the rear of the first carbon dioxide laser beam irradiation part; a breaking unit, including a second carbon dioxide laser beam irradiation part, to break the glass plate, and a second cooling part disposed at the rear of the second carbon dioxide laser beam irradiation part, wherein the first carbon dioxide laser beam irradiation part and the first cooling part are used to generate the scribe line while a plane irradiation density is controlled in a range of 0.05-2 joule/mm 2 on an irradiation area of 20-200 mm 2 by a first control part, wherein the breaking unit is used to break the glass plate while a volume irradiation density is controlled in the range of 0.1-0.5 joule/mm 2 on the irradiation area of 20-200 mm 2 by a second control part.