The Research Of Single Frequency Mode Controled By Assembled Volume Bragg Grating

Single-frequency solid-state laser has many important application in the measur- ing instruments, medical, military and other fields. At present, the methods of obtaining single longitudinal mode are by short cavity, F-P etalon, twisted mode cavity , ring cavity and their assembling. However, the utility of single-frequency laser is limited dues to low single longitudinal mode rate, complex structure or weak ant-jamming capability.The target of this paper is to achieve single-frequency solid-state lasers with high single-longitudinal mode rate and high anti-interference ability. Using a new method of longitudinal mode selection in the Nd: YLF pulse laser .At last, we have obtained single frequency mode at 1053nm.We use volume bragg grating as longitudinal mode selection element, research both transmitting and reflecting volume bragg grating and assemble them as a narrowband filter whose bandwidth is no more than the longitudinal mode spacing. In this condition, only one longitudinal mode can exist, greatly improve the single longitudinal mode rate and anti-interference ability of the single longitudinal mode lasers and greatly simplify the structure of single longitudinal mode laser.Through experimenting in free-run and EQ switch operation, we master the key technology in longitudinal mode selection with two gratings assembly. This work provides a new way to improve the reliability of single frequency mode laser, also provides a guarantee for the application of single frequency mode laser.