| 摘要 |
PROBLEM TO BE SOLVED: To avoid operation in short pulses which is greatly related to the service life of a lens system by installing a laser pulse width detecting means in an excimer laser device. SOLUTION: This excimer laser device consists of a laser pulse waveform detecting means 7, which receives a part of a laser beam and detects the laser pulse waveform of the laser beam, a laser pulse width calculating means 8, which calculates the laser pulse width of the laser beam on the basis of laser pulse waveform data from the laser pulse waveform detecting means 7, and a control means 4 which outputs an abnormal state informing signal, when the laser pulse width is shorter than a prescribed length on the basis of laser pulse width data from the laser pulse width calculating means 8. |
