低温下SHG法测定锁模Ar

In order to measure the pulse width of a mode-locked Ar+ laser in the absence of high speed photodiode and wide band oscilloscope, a zxtw 45°/90° cut KDP plate was designed to be cooled down to-(13.5± 0.1)°C in a refrigarator, phase matching for 5145 A was achieved and the pulse width can be exactly