A laser apparatus including a laser generating portion that generates
pulse light having a single wavelength within a range from an infrared
band to a visible band. An optical amplifier is optically connected to
the laser generating portion, and includes a plurality of fiber optical
amplifiers to amplify the pulse light a plurality of times. A wavelength
converting portion is optically connected to the optical amplifier, and
includes cylindrical lenses and a plurality of non-linear optical
crystals to wavelength-convert the amplified pulse light into ultraviolet
light. The amplified pulse light is incident on the cylindrical lenses
through one of the plurality of non-linear optical crystals and is
incident on a different one of the plurality of non-linear optical
crystals from the one non-linear optical crystal through the cylindrical
lenses.