Patent ID: 10508052

Abstract:
With a method of cutting a tube glass (G1) according to the present invention, the tube glass (G1) is irradiated with laser light (L) having a focal point (F) adjusted to an inside of the tube glass (G1), to thereby form an inner crack region (C1) including one or more cracks in a portion of the tube glass (G1) in a circumferential direction of the tube glass (G1) through multiphoton absorption that occurs in an irradiation region of the laser light (L). Then, in the tube glass (G1), there is generated a stress that urges the one or more cracks in the inner crack region (C1) to propagate in the circumferential direction of the tube glass (G1) to cause the one or more cracks to propagate throughout an entire circumference of the tube glass (G1), to thereby cut the tube glass (G1).