Patent attributes
A laser processing apparatus includes a liquid supply mechanism at an upper portion of a holding unit. The liquid supply mechanism includes: a liquid chamber provided with a transparent plate located with a gap formed between the transparent plate and an upper surface of a workpiece held by the holding table; a liquid supply nozzle adapted to supply a liquid to the gap from one side of the liquid chamber; and a liquid discharge nozzle adapted to recover the liquid from the other side of the liquid chamber, to produce a flow of the liquid. A laser beam applying unit includes a condenser adapted to focus a laser beam emitted by a laser oscillator, to apply the laser beam to the workpiece held by the holding table through the transparent plate and the liquid supplied to the gap.