| 摘要 |
PROBLEM TO BE SOLVED: To produce a blue laser beam by exciting a Pr<3+> -doped solid laser crystal by a laser diode having an active layer comprising a specific composition. SOLUTION: A laser beam having a wavelength of 444 nm produced by an InGaN based laser diode 11 enters a crystal 13 at the rear end surface 13a of a Pr<3> LiYF4 crystal 13. The Pr<3+> of the Pr<3+> LiYF4 crystal 13 is excited by the incident laser beam 10 to produce light having a wavelength of 479 nm by a transition of<3> P0→<3> Ho . The light resonates between coated end surfaces 13a and 13b to generate a laser. A blue laser beam 16 having a wavelength of 479 nm is generated and emitted by the Pr<3+> LiYF4 crystal 13 at the front end surface 13b. |
