A single wavelength laser module utilizes difference-frequency light and
includes a first laser device for oscillating light having a first
wavelength and a second laser device arranged parallel to the first laser
device for oscillating light having a second wavelength, an optical
waveguide device arranged next to the output ends of the first and the
second laser device, and an output optical fiber arranged next to the
output end of the optical waveguide device. The optical waveguide device
includes a coupling waveguide region and an optical wavelength conversion
region. The coupling waveguide region combines light having the first
wavelength and the second wavelength into a single waveguide by being
optically coupled directly to the first and the second laser device. The
optical wavelength conversion region includes an optical waveguide for
generating difference-frequency light between the first wavelength and the
second wavelength. The coupling waveguide region is coupled optically to
the optical wavelength conversion region. The optical fiber is optically
coupled directly to the optical waveguide of the optical waveguide device.
This laser module can provide sufficient optical output without an
isolator and can be mounted easily with a simple configuration.
