There has been a problem that pumping light leaks from a part having a
coating at the joint of a double-clad fiber added with a rare earth and a
general single-mode fiber, and heat is generated partly from the fiber by
this energy thus causing deterioration of the fiber. Deterioration of a
fiber due to residual excitation light can be prevented by preventing
residual excitation light in a double-clad fiber from exiting to a
single-mode fiber, and the reliability is enhanced. Output of oscillation
light can be increased because output of excitation light is not limited.
Furthermore, a laser display having a high color reproducibility can be
achieved by employing a light source combining a fiber laser light source
and a wavelength conversion module.