LD End-pumped All-solid-state Ultraviolet Laser

The ultraviolet laser was achieved by frequency doubling and sum frequency in two crystals by using laser pulses at 1 064 nm. With the maximum incident pump power of 600 mW LD end pumping the average output power of the passively Q switched Nd∶YAG/Cr 4+ ∶YAG 1 064 nm laser is 70 mW and the pulse width is 17.4 ns. Through KTP crystal external cavity frequency doubling and LBO crystal sum frequency, the high efficiency all solid state 355 nm ultraviolet pulse laser was attained by long focusing. The average output power of 355 nm is 106 μW, the peak power is almost 635 mW, and ellipticity is about 0.88.